SAEGW Administration Guide, StarOS Release 16

SAE-GW Administration Guide, StarOS Release
16
Last Updated July 31, 2014
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SAE-GW Administration Guide, StarOS Release 16
© 2014 Cisco Systems, Inc. All rights reserved.
CONTENTS
About this Guide..................................................................................... xvii
Conventions Used............................................................................................................... xviii
Supported Documents and Resources .................................................................................... xix
Related Common Documentation ....................................................................................... xix
Related Product Documentation ..................................................................................... xix
Obtaining Documentation ............................................................................................... xx
Contacting Customer Support ................................................................................................ xxi
SAE Gateway Overview ........................................................................... 23
SAEGW Product Description .................................................................................................. 24
Platform Requirements ...................................................................................................... 25
Licenses .......................................................................................................................... 25
S-GW Product Description ..................................................................................................... 26
Platform Requirements ...................................................................................................... 28
Licenses .......................................................................................................................... 28
P-GW Product Description ..................................................................................................... 29
Platform Requirements ...................................................................................................... 31
Licenses .......................................................................................................................... 31
S-GW Network Deployment(s) ................................................................................................ 32
Serving Gateway in the E-UTRAN/EPC Network.................................................................... 32
Supported Logical Network Interfaces (Reference Points).................................................... 33
P-GW Network Deployment(s) ................................................................................................ 38
PDN Gateway in the E-UTRAN/EPC Network........................................................................ 38
Supported Logical Network Interfaces (Reference Points).................................................... 39
PDN Gateway Supporting eHRPD to E-UTRAN/EPC Connectivity............................................ 44
Supported Logical Network Interfaces (Reference Points).................................................... 45
S-GW Features and Functionality - Base Software..................................................................... 50
ANSI T1.276 Compliance ................................................................................................... 51
APN-level Traffic Policing ................................................................................................... 51
Bulk Statistics Support ....................................................................................................... 51
Circuit Switched Fall Back (CSFB) Support ........................................................................... 52
Closed Subscriber Group Support ....................................................................................... 53
Congestion Control............................................................................................................ 53
Dedicated Bearer Timeout Support on the S-GW ................................................................... 53
Downlink Delay Notification................................................................................................. 54
Value Handling ............................................................................................................. 54
Throttling...................................................................................................................... 54
EPS Bearer ID and ARP Support ..................................................................................... 54
DSCP Ingress and Egress and DSCP Marking at the APN Profile............................................. 54
Dynamic GTP Echo Timer .................................................................................................. 55
Event Reporting................................................................................................................ 55
Idle-mode Signaling Reduction Support ................................................................................ 55
IP Access Control Lists ...................................................................................................... 55
IPv6 Capabilities ............................................................................................................... 56
LIPA Support .................................................................................................................... 56
Location Reporting ............................................................................................................ 57
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Management System Overview .......................................................................................... 57
Multiple PDN Support ........................................................................................................ 58
Node Functionality GTP Echo............................................................................................. 59
Online/Offline Charging ..................................................................................................... 59
Online: Gy Reference Interface ....................................................................................... 59
Offline: Gz Reference Interface ....................................................................................... 59
Offline: Rf Reference Interface........................................................................................ 60
Operator Policy Support..................................................................................................... 60
Peer GTP Node Profile Configuration Support....................................................................... 60
P-GW Restart Notification Support ...................................................................................... 61
QoS Bearer Management .................................................................................................. 61
Rf Diameter Accounting..................................................................................................... 62
S-GW Session Idle Timer................................................................................................... 62
Subscriber Level Trace...................................................................................................... 63
Threshold Crossing Alerts (TCA) Support ............................................................................. 63
P-GW Features and Functionality - Base Software .................................................................... 65
3GPP R9 Volume Charging Over Gx ................................................................................... 66
AAA Server Groups .......................................................................................................... 67
ANSI T1.276 Compliance................................................................................................... 67
APN Support.................................................................................................................... 67
Assume Positive for Gy-based Quota Tracking...................................................................... 68
Bulk Statistics Support....................................................................................................... 69
Congestion Control ........................................................................................................... 70
Default and Dedicated EPC Bearers .................................................................................... 70
DHCP Support ................................................................................................................. 71
DHCPv6 Support .............................................................................................................. 72
Direct Tunnel Support ....................................................................................................... 72
DNS Support for IPv4/IPv6 PDP Contexts ............................................................................ 73
Domain Based Flow Definitions .......................................................................................... 73
DSCP Marking ................................................................................................................. 73
GTP-U on per APN Basis ............................................................................................... 74
Dynamic GTP Echo Timer.................................................................................................. 74
Dynamic Policy Charging Control (Gx Reference Interface)..................................................... 74
Enhanced Charging Service (ECS)...................................................................................... 75
Content Analysis Support ............................................................................................... 77
Content Service Steering ............................................................................................... 78
Support for Multiple Detail Record Types .......................................................................... 78
Diameter Credit Control Application ................................................................................. 79
Accept TCP Connections from DCCA Server .................................................................... 79
Gy Interface Support ..................................................................................................... 79
Gn/Gp Handoff Support ..................................................................................................... 80
IMS Emergency Bearer Handling ........................................................................................ 81
IP Access Control Lists...................................................................................................... 81
IP Address Hold Timers ..................................................................................................... 82
IPv6 Capabilities............................................................................................................... 82
Local Break-Out ............................................................................................................... 83
Management System Overview .......................................................................................... 83
MPLS EXP Marking of User Plane Traffic ............................................................................. 84
Mobile IP Registration Revocation....................................................................................... 85
MTU Size PCO................................................................................................................. 85
Multiple PDN Support ........................................................................................................ 86
Node Functionality GTP Echo............................................................................................. 86
Non-Optimized e-HRPD to Native LTE (E-UTRAN) Mobility Handover ...................................... 86
Online/Offline Charging ..................................................................................................... 87
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Online Charging ............................................................................................................ 87
Offline Charging ............................................................................................................ 88
Peer GTP Node Profile Configuration Support ....................................................................... 89
PMIPv6 Heartbeat ............................................................................................................. 89
Proxy Mobile IPv6 (S2a)..................................................................................................... 89
QoS Bearer Management ................................................................................................... 90
RADIUS Support ............................................................................................................... 90
S-GW Restoration Support ................................................................................................. 92
Source IP Address Validation.............................................................................................. 92
SRVCC PS-to-CS Handover Indication Support ..................................................................... 92
Subscriber Level Trace ...................................................................................................... 93
3GPP Tracing to Intercept Random Subscriber .................................................................. 94
Threshold Crossing Alerts (TCA) Support ............................................................................. 94
UE Time Zone Reporting.................................................................................................... 95
Virtual APN Support .......................................................................................................... 95
P-GW Features and Functionality - Inline Service Support........................................................... 96
Content Filtering ............................................................................................................... 96
Integrated Adult Content Filter......................................................................................... 96
ICAP Interface .............................................................................................................. 97
Header Enrichment: Header Insertion and Encryption............................................................. 97
Mobile Video Gateway ....................................................................................................... 98
Network Address Translation (NAT) ..................................................................................... 99
NAT64 Support ............................................................................................................. 99
Peer-to-Peer Detection .................................................................................................... 100
Personal Stateful Firewall ................................................................................................. 100
Traffic Performance Optimization (TPO) ............................................................................. 101
Features and Functionality - External Application Support ......................................................... 102
Web Element Management System ................................................................................... 102
S-GW Features and Functionality - Optional Enhanced Feature Software.................................... 104
Always-On Licensing ....................................................................................................... 104
Direct Tunnel.................................................................................................................. 104
Intelligent Paging for ISR.................................................................................................. 105
Inter-Chassis Session Recovery ........................................................................................ 106
IP Security (IPSec) Encryption .......................................................................................... 107
Lawful Intercept .............................................................................................................. 107
Layer 2 Traffic Management (VLANs)................................................................................. 107
Session Recovery Support ............................................................................................... 107
P-GW Features and Functionality - Optional Enhanced Feature Software.................................... 109
Always-On Licensing ....................................................................................................... 109
Dynamic RADIUS Extensions (Change of Authorization)....................................................... 110
GRE Protocol Interface Support ........................................................................................ 110
GTP Throttling ................................................................................................................ 111
Inter-Chassis Session Recovery ........................................................................................ 111
IP Security (IPSec) Encryption .......................................................................................... 112
L2TP LAC Support .......................................................................................................... 113
Lawful Intercept .............................................................................................................. 113
Layer 2 Traffic Management (VLANs)................................................................................. 113
Local Policy Decision Engine ............................................................................................ 114
MPLS Forwarding with LDP .............................................................................................. 114
NEMO Service Supported ................................................................................................ 115
NEMO Support in GGSN .............................................................................................. 115
Session Recovery Support ............................................................................................... 115
Smartphone Tethering Detection Support ........................................................................... 116
Traffic Policing................................................................................................................ 116
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User Location Information Reporting...................................................................................117
How the Serving Gateway Works ...........................................................................................119
GTP Serving Gateway Call/Session Procedures in an LTE-SAE Network .................................119
Subscriber-initiated Attach (initial)...................................................................................119
Subscriber-initiated Detach............................................................................................122
How the PDN Gateway Works ...............................................................................................124
PMIPv6 PDN Gateway Call/Session Procedures in an eHRPD Network...................................124
Initial Attach with IPv6/IPv4 Access ................................................................................124
PMIPv6 Lifetime Extension without Handover...................................................................126
PDN Connection Release Initiated by UE ........................................................................127
PDN Connection Release Initiated by HSGW ...................................................................128
PDN Connection Release Initiated by P-GW ....................................................................129
GTP PDN Gateway Call/Session Procedures in an LTE-SAE Network .....................................130
Subscriber-initiated Attach (initial)...................................................................................131
Subscriber-initiated Detach............................................................................................133
S-GW Supported Standards..................................................................................................135
3GPP References............................................................................................................135
Release 10 Supported Standards ...................................................................................135
Release 9 Supported Standards.....................................................................................135
Release 8 Supported Standards.....................................................................................135
3GPP2 References ..........................................................................................................136
IETF References .............................................................................................................136
Object Management Group (OMG) Standards......................................................................137
P-GW Supported Standards..................................................................................................138
Release 11 3GPP References ...........................................................................................138
Release 10 3GPP References ...........................................................................................138
Release 9 3GPP References.............................................................................................138
Release 8 3GPP References.............................................................................................140
3GPP2 References ..........................................................................................................141
IETF References .............................................................................................................141
Object Management Group (OMG) Standards......................................................................142
SAE Gateway Configuration ................................................................... 143
Configuring an SAEGW Service.............................................................................................144
Information Required........................................................................................................144
Required Local Context Configuration Information.............................................................144
Required SAEGW Context Configuration Information ........................................................145
SAEGW Configuration......................................................................................................145
Initial Configuration ......................................................................................................145
SAEGW Service Configuration.......................................................................................146
Verifying and Saving the Configuration............................................................................147
Configuring an eGTP S-GW Service.......................................................................................148
Information Required........................................................................................................148
Required S-GW Ingress Context Configuration Information ................................................148
Required S-GW Egress Context Configuration Information.................................................149
How This Configuration Works...........................................................................................150
eGTP S-GW Configuration................................................................................................151
Initial Configuration ......................................................................................................152
eGTP Configuration......................................................................................................154
Verifying and Saving the Configuration............................................................................156
Configuring Optional Features on the eGTP S-GW ...................................................................157
Configuring the GTP Echo Timer........................................................................................157
Default GTP Echo Timer Configuration............................................................................157
Dynamic GTP Echo Timer Configuration .........................................................................159
Configuring GTPP Offline Accounting on the S-GW ..............................................................163
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Configuring Diameter Offline Accounting on the S-GW.......................................................... 164
Configuring APN-level Traffic Policing on the S-GW ............................................................. 166
Configuring X.509 Certificate-based Peer Authentication....................................................... 167
Configuring Dynamic Node-to-Node IP Security on the S1-U and S5 Interfaces ........................ 168
Creating and Configuring an IPSec Transform Set............................................................ 168
Creating and Configuring an IKEv2 Transform Set............................................................ 169
Creating and Configuring a Crypto Template ................................................................... 170
Binding the S1-U and S5 IP Addresses to the Crypto Template .......................................... 170
Configuring ACL-based Node-to-Node IP Security on the S1-U and S5 Interfaces..................... 171
Creating and Configuring a Crypto Access Control List...................................................... 172
Creating and Configuring an IPSec Transform Set............................................................ 172
Creating and Configuring an IKEv2 Transform Set............................................................ 173
Creating and Configuring a Crypto Map .......................................................................... 174
Configuring S4 SGSN Handover Capability ......................................................................... 176
Configuring an eGTP P-GW Service ...................................................................................... 178
Information Required ....................................................................................................... 178
Required P-GW Context Configuration Information........................................................... 178
Required PDN Context Configuration Information............................................................. 179
Required AAA Context Configuration Information ............................................................. 181
How This Configuration Works .......................................................................................... 184
eGTP P-GW Configuration ............................................................................................... 185
Initial Configuration...................................................................................................... 186
P-GW Service Configuration ......................................................................................... 191
P-GW PDN Context Configuration.................................................................................. 191
Active Charging Service Configuration............................................................................ 193
Policy Configuration..................................................................................................... 195
Verifying and Saving the Configuration ........................................................................... 198
DHCP Service Configuration............................................................................................. 198
DHCP Service Creation................................................................................................ 199
DHCP Server Parameter Configuration........................................................................... 199
DHCP Service Configuration Verification......................................................................... 200
DHCPv6 Service Configuration ......................................................................................... 201
DHCPv6 Service Creation............................................................................................. 202
DHCPv6 Server Parameter Configuration ....................................................................... 202
DHCPv6 Client Parameter Configuration......................................................................... 203
DHCPv6 Profile Configuration ....................................................................................... 203
Associate DHCPv6 Configuration................................................................................... 205
DHCPv6 Service Configuration Verification ..................................................................... 205
Configuring Optional Features on the P-GW............................................................................ 207
Configuring ACL-based Node-to-Node IP Security on the S5 Interface .................................... 207
Creating and Configuring a Crypto Access Control List...................................................... 207
Creating and Configuring an IPSec Transform Set............................................................ 208
Creating and Configuring an IKEv2 Transform Set............................................................ 208
Creating and Configuring a Crypto Map .......................................................................... 209
Configuring APN as Emergency ........................................................................................ 210
Configuring Dynamic Node-to-Node IP Security on the S5 Interface........................................ 211
Creating and Configuring an IPSec Transform Set............................................................ 211
Creating and Configuring an IKEv2 Transform Set............................................................ 212
Creating and Configuring a Crypto Template ................................................................... 212
Binding the S5 IP Address to the Crypto Template ........................................................... 213
Configuring the GTP Echo Timer ....................................................................................... 214
Default GTP Echo Timer Configuration ........................................................................... 214
Dynamic GTP Echo Timer Configuration......................................................................... 216
Configuring GTPP Offline Accounting on the P-GW .............................................................. 219
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Configuring Local QoS Policy ............................................................................................221
Creating and Configuring a Local QoS Policy ...................................................................221
Binding a Local QoS Policy ...........................................................................................222
Verifying Local QoS Policy ............................................................................................223
Configuring X.509 Certificate-based Peer Authentication .......................................................223
Network Mobility (NEMO) ....................................................................... 225
NEMO Overview .................................................................................................................226
Use Cases......................................................................................................................226
Features and Benefits ......................................................................................................227
MIPv4-based NEMO Control Plane.................................................................................227
NEMO MR Authorization...............................................................................................228
MIPv4 NEMO Protocol..................................................................................................228
GRE Encapsulation......................................................................................................228
Session Interactions .....................................................................................................229
NEMO Session Timers .................................................................................................229
Enterprise-wide Route Limit Control ................................................................................229
Forced Fragmentation ..................................................................................................229
Redundancy/Reliability .................................................................................................229
LTE NEMO Call Flow .......................................................................................................230
Engineering Rules ...........................................................................................................232
Supported Standards .......................................................................................................232
NEMO Configuration............................................................................................................233
Sample Configuration.......................................................................................................233
Create a VRF..................................................................................................................234
Set Neighbors and Address Family.....................................................................................235
Redistribute Connected Routes .........................................................................................235
Configure and Enable NEMO in APN Profile ........................................................................235
Create a NEMO HA .........................................................................................................236
Operator Policy ...................................................................................... 237
What Operator Policy Can Do ...............................................................................................238
A Look at Operator Policy on an SGSN...............................................................................238
A Look at Operator Policy on an S-GW ...............................................................................238
The Operator Policy Feature in Detail .....................................................................................239
Call Control Profile...........................................................................................................239
APN Profile.....................................................................................................................240
IMEI-Profile (SGSN only) ..................................................................................................241
APN Remap Table...........................................................................................................241
Operator Policies .............................................................................................................242
IMSI Ranges ...................................................................................................................242
How It Works ......................................................................................................................244
Operator Policy Configuration................................................................................................245
Call Control Profile Configuration .......................................................................................246
Configuring the Call Control Profile for an SGSN ..............................................................246
Configuring the Call Control Profile for an MME or S-GW ...................................................246
APN Profile Configuration .................................................................................................247
IMEI Profile Configuration - SGSN only ...............................................................................247
APN Remap Table Configuration .......................................................................................248
Operator Policy Configuration............................................................................................248
IMSI Range Configuration.................................................................................................249
Configuring IMSI Ranges on the MME or S-GW ...............................................................249
Configuring IMSI Ranges on the SGSN...........................................................................249
Associating Operator Policy Components on the MME ..........................................................250
Configuring Accounting Mode for S-GW ..............................................................................251
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Verifying the Feature Configuration........................................................................................ 252
S-GW Event Reporting ............................................................................253
Event Record Triggers ......................................................................................................... 254
Event Record Elements ....................................................................................................... 255
Active-to-Idle Transitions...................................................................................................... 257
3GPP 29.274 Cause Codes.................................................................................................. 258
Configuring Subscriber Session Tracing ................................................261
Introduction........................................................................................................................ 262
Supported Functions........................................................................................................ 263
Supported Standards........................................................................................................... 265
Subscriber Session Trace Functional Description..................................................................... 266
Operation....................................................................................................................... 266
Trace Session............................................................................................................. 266
Trace Recording Session.............................................................................................. 266
Network Element (NE) ..................................................................................................... 266
Activation....................................................................................................................... 266
Management Activation ................................................................................................ 267
Signaling Activation ..................................................................................................... 267
Start Trigger ................................................................................................................... 267
Deactivation ................................................................................................................... 267
Stop Trigger ................................................................................................................... 267
Data Collection and Reporting........................................................................................... 267
Trace Depth ............................................................................................................... 267
Trace Scope............................................................................................................... 268
Network Element Details .................................................................................................. 268
MME ......................................................................................................................... 268
S-GW ........................................................................................................................ 268
P-GW ........................................................................................................................ 269
Subscriber Session Trace Configuration................................................................................. 270
Enabling Subscriber Session Trace on EPC Network Element ............................................... 270
Trace File Collection Configuration .................................................................................... 271
Verifying Your Configuration ................................................................................................. 272
Monitoring the Service............................................................................275
Monitoring System Status and Performance............................................................................ 276
Clearing Statistics and Counters ........................................................................................... 280
CoA, RADIUS DM, and Session Redirection (Hotlining) ..........................281
RADIUS Change of Authorization and Disconnect Message ...................................................... 282
CoA Overview ................................................................................................................ 282
DM Overview.................................................................................................................. 282
License Requirements ..................................................................................................... 282
Enabling CoA and DM ..................................................................................................... 282
Enabling CoA and DM.................................................................................................. 283
CoA and DM Attributes................................................................................................. 283
CoA and DM Error-Cause Attribute ................................................................................ 284
Viewing CoA and DM Statistics...................................................................................... 285
Session Redirection (Hotlining) ............................................................................................. 288
Overview ....................................................................................................................... 288
License Requirements.................................................................................................. 288
Operation....................................................................................................................... 288
ACL Rule ................................................................................................................... 288
Redirecting Subscriber Sessions ................................................................................... 288
Session Limits On Redirection....................................................................................... 289
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Stopping Redirection ....................................................................................................289
Handling IP Fragments .................................................................................................289
Recovery ....................................................................................................................289
AAA Accounting...........................................................................................................289
Viewing the Redirected Session Entries for a Subscriber .......................................................289
Direct Tunnel.......................................................................................... 295
Direct Tunnel Feature Overview.............................................................................................296
Direct Tunnel Configuration...................................................................................................300
Configuring Direct Tunnel Support on the SGSN ..................................................................300
Enabling Setup of GTP-U Direct Tunnels .........................................................................301
Enabling Direct Tunnel per APN.....................................................................................301
Enabling Direct Tunnel per IMEI.....................................................................................302
Enabling Direct Tunnel to Specific RNCs .........................................................................302
Verifying the SGSN Direct Tunnel Configuration ...............................................................303
Configuring S12 Direct Tunnel Support on the S-GW ............................................................305
GRE Protocol Interface........................................................................... 307
Introduction ........................................................................................................................308
Supported Standards ...........................................................................................................309
Supported Networks and Platforms ........................................................................................310
Licenses ............................................................................................................................311
Services and Application on GRE Interface .............................................................................312
How GRE Interface Support Works ........................................................................................313
Ingress Packet Processing on GRE Interface.......................................................................313
Egress Packet Processing on GRE Interface .......................................................................315
GRE Interface Configuration .................................................................................................316
Virtual Routing And Forwarding (VRF) Configuration.............................................................316
GRE Tunnel Interface Configuration ...................................................................................317
Enabling OSPF for VRF....................................................................................................318
Associating IP Pool and AAA Group with VRF......................................................................318
Associating APN with VRF ................................................................................................319
Static Route Configuration ................................................................................................319
Verifying Your Configuration..................................................................................................320
Gx Interface Support .............................................................................. 323
Rel. 6 Gx Interface...............................................................................................................324
Introduction.....................................................................................................................324
Supported Networks and Platforms.................................................................................324
License Requirements ..................................................................................................325
Supported Standards....................................................................................................325
How it Works ..................................................................................................................325
Configuring Rel. 6 Gx Interface..........................................................................................327
Configuring IMS Authorization Service at Context Level .....................................................327
Verifying IMS Authorization Service Configuration.............................................................329
Applying IMS Authorization Service to an APN .................................................................329
Verifying Subscriber Configuration..................................................................................329
Rel. 7 Gx Interface...............................................................................................................330
Introduction.....................................................................................................................330
Supported Networks and Platforms.................................................................................332
License Requirements ..................................................................................................332
Supported Standards....................................................................................................332
Terminology and Definitions ..............................................................................................332
Policy Control..............................................................................................................332
Charging Control..........................................................................................................336
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Policy and Charging Control (PCC) Rules ....................................................................... 336
PCC Procedures over Gx Reference Point ...................................................................... 338
Volume Reporting Over Gx ........................................................................................... 340
How Rel. 7 Gx Works....................................................................................................... 344
Configuring Rel. 7 Gx Interface ......................................................................................... 347
Configuring IMS Authorization Service at Context Level .................................................... 347
Applying IMS Authorization Service to an APN................................................................. 350
Configuring Volume Reporting over Gx ........................................................................... 351
Gathering Statistics ......................................................................................................... 351
Rel. 8 Gx Interface .............................................................................................................. 353
HA/PDSN Rel. 8 Gx Interface Support................................................................................ 353
Introduction ................................................................................................................ 353
Terminology and Definitions .......................................................................................... 355
How it Works .............................................................................................................. 361
Configuring HA/PDSN Rel. 8 Gx Interface Support ........................................................... 363
Gathering Statistics...................................................................................................... 366
P-GW Rel. 8 Gx Interface Support ..................................................................................... 367
Introduction ................................................................................................................ 367
Terminology and Definitions .......................................................................................... 368
Rel. 9 Gx Interface .............................................................................................................. 373
P-GW Rel. 9 Gx Interface Support ..................................................................................... 373
Introduction ................................................................................................................ 373
Terminology and Definitions .......................................................................................... 373
Assume Positive for Gx........................................................................................................ 378
Default Policy on CCR-I Failure......................................................................................... 379
Gx Back off Functionality .................................................................................................. 380
Configuring Gx Assume Positive Feature............................................................................ 380
Configuring Local Policy Service at Global Configuration Level........................................... 380
Configuring Failure Handling Template at Global Configuration Level .................................. 382
Associating Local Policy Service and Failure Handling Template ........................................ 382
Verifying Local Policy Service Configuration .................................................................... 382
Time Reporting Over Gx ...................................................................................................... 383
License Requirements ..................................................................................................... 383
Feature Overview............................................................................................................ 383
Limitations.................................................................................................................. 384
Usage Monitoring............................................................................................................ 384
Usage Monitoring at Session Level ................................................................................ 384
Usage Monitoring at Flow Level ..................................................................................... 384
Usage Reporting............................................................................................................. 385
Configuring Time Reporting over Gx .................................................................................. 385
Gy Interface Support...............................................................................387
Introduction........................................................................................................................ 388
License Requirements ..................................................................................................... 389
Supported Standards ....................................................................................................... 389
Features and Terminology.................................................................................................... 390
Charging Scenarios ......................................................................................................... 390
Session Charging with Reservation ................................................................................ 390
Basic Operations ......................................................................................................... 390
Re-authorization.......................................................................................................... 391
Threshold based Re-authorization Triggers ..................................................................... 391
Termination Action....................................................................................................... 391
Diameter Base Protocol ................................................................................................... 391
Diameter Credit Control Application ................................................................................... 392
Quota Behavior ........................................................................................................... 393
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Supported AVPs ..........................................................................................................404
Unsupported AVPs.......................................................................................................407
PLMN and Time Zone Reporting........................................................................................413
Interworking between Session-based Gy and Event-based Gy............................................414
OCS Unreachable Failure Handling Feature ........................................................................414
Backpressure..................................................................................................................416
Gy Backpressure Enhancement .....................................................................................416
Configuring Gy Interface Support ...........................................................................................418
Configuring GGSN / P-GW / IPSG Gy Interface Support ........................................................418
Configuring HA / PDSN Gy Interface Support.......................................................................419
Configuring PLMN and Time Zone Reporting .......................................................................421
Configuring Server Unreachable Feature.............................................................................423
Gathering Statistics ..........................................................................................................423
ICAP Interface Support........................................................................... 425
ICAP Interface Support Overview...........................................................................................426
Failure Action on Retransmitted Packets .............................................................................427
Supported Networks and Platforms ....................................................................................428
License Requirements ......................................................................................................428
Configuring ICAP Interface Support........................................................................................429
Creating ICAP Server Group and Address Binding................................................................429
Configuring ICAP Server and Other Parameters ...................................................................430
Configuring ECS Rulebase for ICAP Server Group ...............................................................430
Configuring Charging Action for ICAP Server Group .............................................................431
Verifying the ICAP Server Group Configuration ....................................................................431
L2TP Access Concentrator..................................................................... 433
Applicable Products and Relevant Sections .............................................................................434
Supported LAC Service Configurations for PDSN Simple IP.......................................................435
Attribute-based Tunneling .................................................................................................435
How The Attribute-based L2TP Configuration Works .........................................................436
Configuring Attribute-based L2TP Support for PDSN Simple IP...........................................436
PDSN Service-based Compulsory Tunneling .......................................................................437
How PDSN Service-based Compulsory Tunneling Works...................................................437
Configuring L2TP Compulsory Tunneling Support for PDSN Simple IP.................................438
Supported LAC Service Configurations for the GGSN and P-GW................................................440
Transparent IP PDP Context Processing with L2TP Support ..................................................441
Non-transparent IP PDP Context Processing with L2TP Support.............................................442
PPP PDP Context Processing with L2TP Support .................................................................443
Configuring the GGSN or P-GW to Support L2TP .................................................................444
Supported LAC Service Configuration for Mobile IP ..................................................................445
How The Attribute-based L2TP Configuration for MIP Works ..................................................445
Configuring Attribute-based L2TP Support for HA Mobile IP ...................................................446
Configuring Subscriber Profiles for L2TP Support .....................................................................448
RADIUS and Subscriber Profile Attributes Used ...................................................................448
RADIUS Tagging Support .............................................................................................449
Configuring Local Subscriber Profiles for L2TP Support .........................................................449
Configuring Local Subscriber.............................................................................................450
Verifying the L2TP Configuration........................................................................................450
Tunneling All Subscribers in a Specific Context Without Using RADIUS Attributes .................451
Configuring LAC Services .....................................................................................................452
Configuring LAC Service...................................................................................................452
Configuring LNS Peer ......................................................................................................453
Verifying the LAC Service Configuration..............................................................................453
Modifying PDSN Services for L2TP Support ............................................................................455
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Modifying PDSN Service .................................................................................................. 455
Verifying the PDSN Service for L2TP Support ..................................................................... 456
Modifying APN Templates to Support L2TP ............................................................................ 457
Assigning LNS Peer Address in APN Template.................................................................... 457
Configuring Outbound Authentication ................................................................................. 458
Verifying the APN Configuration ........................................................................................ 458
Mobile IP Registration Revocation ..........................................................459
Overview ........................................................................................................................... 460
Configuring Registration Revocation ...................................................................................... 462
Configuring FA Services................................................................................................... 462
Configuring HA Services .................................................................................................. 462
Multi-Protocol Label Switching (MPLS) Support .....................................465
Overview ........................................................................................................................... 466
Chassis as MPLS-CE Connecting to PE ............................................................................. 466
Chassis as MPLS-CE Connected to ASBR ......................................................................... 467
Engineering Rules ........................................................................................................... 467
Supported Standards........................................................................................................... 468
Supported Networks and Platforms........................................................................................ 469
Licenses ............................................................................................................................ 470
Benefits ............................................................................................................................. 471
Configuring BGP/MPLS VPN with Static Labels ....................................................................... 472
Create VRF with Route-distinguisher and Route-target ......................................................... 472
Set Neighbors and Enable VPNv4 Route Exchange ............................................................. 473
Configure Address Family and Redistributed Connected Routes ............................................ 473
Configure IP Pools with MPLS Labels ................................................................................ 474
Bind DHCP Service for Corporate Servers .......................................................................... 474
Bind AAA Group for Corporate Servers............................................................................... 474
Configuring BGP/MPLS VPN with Dynamic Labels .................................................................. 476
Create VRF with Route-distinguisher and Route-target ......................................................... 476
Set Neighbors and Enable VPNv4 Route Exchange ............................................................. 477
Configure Address Family and Redistributed Connected Routes ............................................ 478
Configure IP Pools with MPLS Labels ................................................................................ 478
Bind DHCP Service for Corporate Servers .......................................................................... 478
Bind AAA Group for Corporate Servers............................................................................... 479
DSCP and EXP Bit Mapping ............................................................................................. 479
Proxy-Mobile IP ......................................................................................481
Overview ........................................................................................................................... 482
Proxy Mobile IP in 3GPP2 Service ..................................................................................... 483
Proxy Mobile IP in 3GPP Service....................................................................................... 483
Proxy Mobile IP in WiMAX Service..................................................................................... 484
How Proxy Mobile IP Works in 3GPP2 Network ....................................................................... 485
Scenario 1: AAA server and PDSN/FA Allocate IP Address ................................................... 485
Scenario 2: HA Allocates IP Address.................................................................................. 487
How Proxy Mobile IP Works in 3GPP Network......................................................................... 490
How Proxy Mobile IP Works in WiMAX Network ...................................................................... 493
Scenario 1: AAA server and ASN GW/FA Allocate IP Address ............................................... 493
Scenario 2: HA Allocates IP Address.................................................................................. 495
How Proxy Mobile IP Works in a WiFi Network with Multiple Authentication ................................. 498
Configuring Proxy Mobile-IP Support ..................................................................................... 503
Configuring FA Services................................................................................................... 503
Verify the FA Service Configuration.................................................................................... 504
Configuring Proxy MIP HA Failover .................................................................................... 504
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▀ Contents
Configuring HA Services ...................................................................................................505
Configuring Subscriber Profile RADIUS Attributes.................................................................506
RADIUS Attributes Required for Proxy Mobile IP ..............................................................506
Configuring Local Subscriber Profiles for Proxy-MIP on a PDSN .........................................507
Configuring Local Subscriber Profiles for Proxy-MIP on a PDIF...........................................508
Configuring Default Subscriber Parameters in Home Agent Context ....................................508
Configuring APN Parameters .........................................................................................508
Rf Interface Support ............................................................................... 511
Introduction ........................................................................................................................512
Offline Charging Architecture.............................................................................................512
Charging Collection Function.........................................................................................514
Charging Trigger Function.............................................................................................514
Dynamic Routing Agent ................................................................................................514
License Requirements ......................................................................................................514
Supported Standards .......................................................................................................514
Features and Terminology ....................................................................................................516
Offline Charging Scenarios................................................................................................516
Basic Principles ...........................................................................................................516
Event Based Charging..................................................................................................517
Session Based Charging...............................................................................................517
Diameter Base Protocol ....................................................................................................518
Timer Expiry Behavior ......................................................................................................519
Rf Interface Failures/Error Conditions .................................................................................519
DRA/CCF Connection Failure ........................................................................................519
No Reply from CCF......................................................................................................519
Detection of Message Duplication...................................................................................519
CCF Detected Failure...................................................................................................519
Rf-Gy Synchronization Enhancements ................................................................................520
Cessation of Rf Records When UE is IDLE ..........................................................................520
How it Works ......................................................................................................................521
Configuring Rf Interface Support ............................................................................................523
Enabling Rf Interface in Active Charging Service ..................................................................523
Configuring GGSN / P-GW Rf Interface Support ...................................................................524
Configuring HSGW Rf Interface Support .............................................................................531
Configuring P-CSCF/S-CSCF Rf Interface Support ...............................................................541
Enabling Charging for SIP Methods ................................................................................542
Configuring S-GW Rf Interface Support...............................................................................543
Gathering Statistics ..........................................................................................................554
S-GW Restoration Support ..................................................................... 559
Feature Description .............................................................................................................560
Relationships to Other Features .........................................................................................560
How it Works ......................................................................................................................561
Changes at P-GW............................................................................................................561
Changes at the E-GTPC ...................................................................................................561
Changes at the MME and SGSN........................................................................................561
Demux Failure Detection ..................................................................................................561
Standards Compliance .....................................................................................................562
Configuring S-GW Restoration Support...................................................................................563
Sample Configuration.......................................................................................................563
Verifying the S-GW Configuration.......................................................................................563
Monitoring and Troubleshooting S-GW Restoration Support.......................................................565
S-GW Show Commands ...................................................................................................565
show ims-authorization policy-control statistics .................................................................565
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Contents ▀
show pgw-service statistics all....................................................................................... 565
show subscribers pgw-only full all .................................................................................. 565
Traffic Policing and Shaping ...................................................................567
Overview ........................................................................................................................... 568
Traffic Policing................................................................................................................ 568
Traffic Shaping ............................................................................................................... 568
Traffic Policing Configuration ................................................................................................ 569
Configuring Subscribers for Traffic Policing ......................................................................... 569
Configuring APN for Traffic Policing in 3GPP Networks ......................................................... 570
Traffic Shaping Configuration................................................................................................ 572
Configuring Subscribers for Traffic Shaping......................................................................... 572
Configuring APN for Traffic Shaping in 3GPP Networks ........................................................ 573
RADIUS Attributes .............................................................................................................. 576
Traffic Policing for CDMA Subscribers ................................................................................ 576
Traffic Policing for UMTS Subscribers ................................................................................ 577
S-GW Engineering Rules ........................................................................579
Interface and Port Rules ...................................................................................................... 580
Assumptions .................................................................................................................. 580
S1-U/S11 Interface Rules ................................................................................................. 580
S5/S8 Interface Rules ...................................................................................................... 580
MAG to LMA Rules ...................................................................................................... 581
S-GW Service Rules ........................................................................................................... 582
S-GW Subscriber Rules ....................................................................................................... 583
P-GW Engineering Rules ........................................................................585
Interface and Port Rules ...................................................................................................... 586
S2a Interface Rules ......................................................................................................... 586
LMA to MAG............................................................................................................... 586
S5/S8 Interface Rules (GTP)............................................................................................. 586
P-GW Context and Service Rules .......................................................................................... 587
P-GW Subscriber Rules ....................................................................................................... 588
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About this Guide
This preface describes the S-GW Administration Guide, how it is organized and its document conventions.
The Serving Gateway (S-GW) routes and forwards data packets from the UE and acts as the mobility anchor during
inter-eNodeB handovers. Signals controlling the data traffic are received on the S-GW from the MME which determines
the S-GW that will best serve the UE for the session. Every UE accessing the EPC is associated with a single S-GW.
This document provides feature descriptions, configuration procedures and monitoring and troubleshooting information.
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About this Guide
▀ Conventions Used
Conventions Used
The following tables describe the conventions used throughout this documentation.
Icon
Notice Type
Description
Information Note
Provides information about important features or instructions.
Caution
Alerts you of potential damage to a program, device, or system.
Warning
Alerts you of potential personal injury or fatality. May also alert you of potential electrical hazards.
Typeface Conventions
Description
Text represented as a screen
display
This typeface represents displays that appear on your terminal screen, for example:
Login:
Text represented as commands
This typeface represents commands that you enter, for example:
show ip access-list
This document always gives the full form of a command in lowercase letters. Commands
are not case sensitive.
Text represented as a command
This typeface represents a variable that is part of a command, for example:
variable
show card slot_number
slot_number is a variable representing the desired chassis slot number.
Text represented as menu or submenu names
This typeface represents menus and sub-menus that you access within a software
application, for example:
Click the File menu, then click New
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About this Guide
Supported Documents and Resources ▀
Supported Documents and Resources
Related Common Documentation
The most up-to-date information for this product is available in the product Release Notes provided with each product
release.
The following common documents are available:
 Hardware Installation Guide (hardware dependent)
 System Administration Guide (hardware dependent)
 Command Line Interface Reference
 AAA Interface Administration Reference
 GTPP Interface Administration Reference
 Product Overview
 Release Change Reference
 Statistics and Counters Reference
 Thresholding Configuration Guide
Related Product Documentation
The following product documents are also available and work in conjunction with the S-GW:
 SNMP MIB Reference
 StarOS IP Security (IPSec) Reference
 Web Element Manager Installation and Administration Guide
 GTPP Interface Administration and Reference
 GGSN Administration Guide
 HRPD-SGW Administration Guide
 IPSG Administration Guide
 MME Administration Guide
 P-GW Administration Guide
 PDSN Administration Guide
 SAE-GW Administration Guide
 SGSN Administration Guide
 SCM Administration Guide
 PDG/TTG Administration Guide
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About this Guide
▀ Supported Documents and Resources
 Release notes that accompany updates and upgrades to the StarOS for your service and platform
Obtaining Documentation
The most current Cisco documentation is available on the following website:
http://www.cisco.com/cisco/web/psa/default.html
Use the following path selections to access the S-GW documentation:
Products > Wireless > Mobile Internet> Network Functions > Cisco SGW Serving Gateway
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About this Guide
Contacting Customer Support ▀
Contacting Customer Support
Use the information in this section to contact customer support.
Refer to the support area of http://www.cisco.com for up-to-date product documentation or to submit a service request.
A valid username and password are required to access this site. Please contact your Cisco sales or service representative
for additional information.
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Chapter 1
SAE Gateway Overview
The Cisco® ASR 5x00 provides wireless carriers with a flexible solution that functions as a System Architecture
Evolution (SAE) Gateway with Packet Data Network (PDN) Gateway (P-GW) and Serving Gateway (S-GW) functions
in LTE-SAE (3GPP2 Long Term Evolution-System Architecture Evolution) wireless data networks.
This overview provides general information about the SAEGW including:
 SAEGW Product Description
 S-GW Product Description
 P-GW Product Description
 S-GW Network Deployment(s)
 P-GW Network Deployment(s)
 S-GW Features and Functionality - Base Software
 P-GW Features and Functionality - Base Software
 P-GW Features and Functionality - Inline Service Support
 Features and Functionality - External Application Support
 S-GW Features and Functionality - Optional Enhanced Feature Software
 P-GW Features and Functionality - Optional Enhanced Feature Software
 How the Serving Gateway Works
 How the PDN Gateway Works
 S-GW Supported Standards
 P-GW Supported Standards
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SAE Gateway Overview
▀ SAEGW Product Description
SAEGW Product Description
The SAEGW node is a combination of S-GW and P-GW nodes. SAEGW operates as a service on ASR5x00 and
requires existing S-GW and P-GW services to be configured and mentioned inside SAEGW service configuration.
Existing standalone S-GW and P-GW services (when part of an SAEGW umbrella service) will work in tandem to
present a single SAEGW node as a black-box view.
The SAEGW supports all of the interfaces that the standalone S-GW and P-GW products support, namely:
 S11/S4 – GTPv2 based control interface towards MME/S4-SGSN
 S1U/S12/S4U – GTPv1 based data interface towards eNodeB/RNC/S4-SGSN
 S5/S8 – GTPv2 based control interface between S-GW and P-GW
 Gi – Data interface towards packet data network
 Gx – Diameter based interface between P-GW and PCRF
 S6b – Diameter based interface between P-GW and HSS
 Rf – Diameter based offline charging interface between P-GW/S-GW and charging data function
 Gy – GTPP based online charging interface between P-GW and online charging system
 Gz – GTPP based offline charging interface between P-GW/S-GW and charging gateway function
Mode of operation is described as the functionality performed by SAEGW for a call. Granularity for mode of operation
is per-PDN. The SAEGW service supports the following three modes of operation:
 S+P Collapsed: When a UE is using S-GW part of SAEGW and a PDN connection is terminating within the PGW part of SAEGW.
 Pure-S: When a UE is using S-GW part of SAEGW and a PDN connection is terminating at an external P-GW
not part of SAEGW.
 Pure-P: When a UE is using an external S-GW not part of SAEGW and a PDN connection is terminating within
P-GW part of SAEGW.
Important: For a given UE with multiple PDNs, SAEGW will be able to support S+P mode for some PDNs
while Pure-S mode for others.
Important: SAEGW supports change of operation-mode in life of a PDN. For example, a PDN initially doing
S+P mode may change to doing Pure-P if S-GW gets relocated to external S-GW that is not part of SAEGW. Similarly,
a PDN doing Pure-P mode may change to S+P mode if S-GW relocated so that new S-GW is part of SAEGW service.
An optimized SAEGW provides the following benefits:
 Higher Capacity
A UE with one PDN connection that passes through standalone S-GW and P-GW services consumes two
license units because both S-GW and P-GW services account for it separately. SAEGW as a single node
consumes only one license unit for the same, thus increasing the capacity. Contact your Cisco account
representative for detailed information on product licensing.
 Cohesive Configuration
Configuration and management of SAEGW as a node is easier to follow than starting standalone S-GW and PGW services.
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SAE Gateway Overview
SAEGW Product Description ▀
Platform Requirements
The SAEGW service runs on a Cisco® ASR 5x00 Series chassis running StarOS. The chassis can be configured with a
variety of components to meet specific network deployment requirements. For additional information, refer to the
Installation Guide for the chassis and/or contact your Cisco account representative.
Licenses
The SAEGW is a licensed Cisco product. Separate session and feature licenses may be required. Contact your Cisco
account representative for detailed information on specific licensing requirements. For information on installing and
verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in the
System Administration Guide.
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SAE Gateway Overview
▀ S-GW Product Description
S-GW Product Description
The Serving Gateway routes and forwards data packets from the UE and acts as the mobility anchor during intereNodeB handovers. Signals controlling the data traffic are received on the S-GW from the MME which determines the
S-GW that will best serve the UE for the session. Every UE accessing the EPC is associated with a single S-GW.
Figure 1.
S-GW in the Basic E-UTRAN/EPC Network
The S-GW is also involved in mobility by forwarding down link data during a handover from the E-UTRAN to the
eHRPD network. An interface from the eAN/ePCF to an MME provides signaling that creates a GRE tunnel between
the S-GW and the eHRPD Serving Gateway.
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SAE Gateway Overview
S-GW Product Description ▀
Figure 2.
S-GW in the Basic E-UTRAN/EPC and eHRPD Network
The functions of the S-GW include:
 packet routing and forwarding.
 providing the local mobility anchor (LMA) point for inter-eNodeB handover and assisting the eNodeB
reordering function by sending one or more “end marker” packets to the source eNodeB immediately after
switching the path.
 mobility anchoring for inter-3GPP mobility (terminating the S4 interface from an SGSN and relaying the traffic
between 2G/3G system and a PDN gateway.
 packet buffering for ECM-IDLE mode downlink and initiation of network triggered service request procedure.
 replicating user traffic in the event that Lawful Interception (LI) is required.
 transport level packet marking.
 user accounting and QoS class indicator (QCI) granularity for charging.
 uplink and downlink charging per UE, PDN, and QCI.
 reporting of user location information (ULI).
 support of circuit switched fallback (CSFB) for re-using deployed CS domain access for voice and other CS
domain services.
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SAE Gateway Overview
▀ S-GW Product Description
Platform Requirements
The S-GW service runs on a Cisco® ASR 5x00 Series chassis running StarOS. The chassis can be configured with a
variety of components to meet specific network deployment requirements. For additional information, refer to the
Installation Guide for the chassis and/or contact your Cisco account representative.
Licenses
The S-GW is a licensed Cisco product covered by the SAEGW license when part of an SAEGW umbrella service.
Separate session and feature licenses may be required. Contact your Cisco account representative for detailed
information on specific licensing requirements. For information on installing and verifying licenses, refer to the
Managing License Keys section of the Software Management Operations chapter in the System Administration Guide.
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SAE Gateway Overview
P-GW Product Description ▀
P-GW Product Description
The P-GW is the node that terminates the SGi interface towards the PDN. If a UE is accessing multiple PDNs, there
may be more than one P-GW for that UE. The P-GW provides connectivity to the UE to external packet data networks
by being the point of exit and entry of traffic for the UE. A UE may have simultaneous connectivity with more than one
P-GW for accessing multiple PDNs. The P-GW performs policy enforcement, packet filtering for each user, charging
support, lawful interception and packet screening.
Figure 3.
P-GW in the Basic E-UTRAN/EPC Network
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SAE Gateway Overview
▀ P-GW Product Description
Figure 4.
P-GW in the Basic E-UTRAN/EPC and eHRPD Network
Another key role of the P-GW is to act as the anchor for mobility between 3GPP and non-3GPP technologies such as
WiMAX and 3GPP2 (CDMA 1X and EvDO).
P-GW functions include:
 Mobility anchor for mobility between 3GPP access systems and non-3GPP access systems. This is sometimes
referred to as the SAE Anchor function.
 Policy enforcement (gating and rate enforcement)
 Per-user based packet filtering (deep packet inspection)
 Charging support
 Lawful Interception
 UE IP address allocation
 Packet screening
 Transport level packet marking in the downlink;
 Down link rate enforcement based on Aggregate Maximum Bit Rate (AMBR)
The following are additional P-GW functions when supporting non-3GPP access (eHRPD):
 P-GW includes the function of a Local Mobility Anchor (LMA) according to draft-ietf-netlmm-proxymip6, if
PMIP-based S5 or S8 is used.
 The P-GW includes the function of a DSMIPv6 Home Agent, as described in draft-ietf-mip6-nemo-v4traversal,
if S2c is used.
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SAE Gateway Overview
P-GW Product Description ▀
Platform Requirements
The P-GW service runs on a Cisco® ASR 5x00 chassis running StarOS. The chassis can be configured with a variety of
components to meet specific network deployment requirements. For additional information, refer to the Installation
Guide for the chassis and/or contact your Cisco account representative.
Licenses
The P-GW is a licensed Cisco product covered by the SAEGW license when part of an SAEGW umbrella service.
Separate session and feature licenses may be required. Contact your Cisco account representative for detailed
information on specific licensing requirements. For information on installing and verifying licenses, refer to the
Managing License Keys section of the Software Management Operations chapter in the System Administration Guide.
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SAE Gateway Overview
▀ S-GW Network Deployment(s)
S-GW Network Deployment(s)
This section describes the supported interfaces and the deployment scenarios of a Serving Gateway.
Serving Gateway in the E-UTRAN/EPC Network
The following figure displays the specific network interfaces supported by the S-GW. Refer to Supported Logical
Network Interfaces (Reference Points) for detailed information about each interface.
Figure 5.
Supported S-GW Interfaces in the E-UTRAN/EPC Network
The following figure displays a sample network deployment of an S-GW, including all of the interface connections with
other 3GPP Evolved-UTRAN/Evolved Packet Core network devices.
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SAE Gateway Overview
S-GW Network Deployment(s) ▀
Figure 6.
S-GW in the E-UTRAN/EPC Network
Supported Logical Network Interfaces (Reference Points)
The S-GW provides the following logical network interfaces in support of the E-UTRAN/EPC network:
S1-U Interface
This reference point provides bearer channel tunneling between the eNodeB and the S-GW. It also supports eNodeB
path switching during handovers. The S-GW provides the local mobility anchor point for inter-eNodeB hand-overs. It
provides inter-eNodeB path switching during hand-overs when the X2 handover interface between base stations cannot
be used. The S1-U interface uses GPRS tunneling protocol for user plane (GTP-Uv1). GTP encapsulates all end user IP
packets and it relies on UDP/IP transport. The S1-U interface also supports IPSec IKEv2. This interface is defined in
3GPP TS 23.401.
Supported protocols:
 Transport Layer: UDP, TCP
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SAE Gateway Overview
▀ S-GW Network Deployment(s)
 Tunneling: IPv4 or IPv6 GTPv1-U (bearer channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
S4 Interface
This reference point provides tunneling and management between the S-GW and a 3GPP S4 SGSN. The interface
facilitates soft hand-offs with the EPC network by providing control and mobility support between the inter-3GPP
anchor function of the S-GW. This interface is defined in 3GPP TS 23.401.
Supported protocols:
 Transport Layer: UDP
 Tunneling:
 GTP: IPv4 or IPv6 GTP-C (GTPv2 control/signaling channel) and GTP-U (GTPv1 user/bearer channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
S5/S8 Interface
This reference point provides tunneling and management between the S-GW and the P-GW, as defined in 3GPP TS
23.401. The S8 interface is an inter-PLMN reference point between the S-GW and the P-GW used during roaming
scenarios. The S5 interface is used between an S-GW and P-GW located within the same administrative domain (non▄ SAE-GW Administration Guide, StarOS Release 16
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S-GW Network Deployment(s) ▀
roaming). It is used for S-GW relocation due to UE mobility and if the S-GW needs to connect to a non-collocated PGW for the required PDN connectivity.
Supported protocols:
 Transport Layer: UDP, TCP
 Tunneling: GTP: GTPv2-C (signaling channel), GTPv1-U (bearer channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
S11 Interface
This reference point provides GTP-C control signal tunneling between the MME and the S-GW. One GTP-C tunnel is
created for each mobile terminal between the MME and S-GW. This interface is defined in 3GPP TS 23.401.
Supported protocols:
 Transport Layer: UDP
 Tunneling: IPv4 or IPv6 GTPv2-C (signalling channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
S12 Interface
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SAE Gateway Overview
▀ S-GW Network Deployment(s)
This reference point provides GTP-U bearer/user direct tunneling between the S-GW and a UTRAN Radio Network
Controller (RNC), as defined in 3GPP TS 23.401. This interface provides support for inter-RAT handovers between the
3G RAN and EPC allowing a direct tunnel to be initiated between the RNC and S-GW, thus bypassing the S4 SGSN
and reducing latency.
Supported protocols:
 Transport Layer: UDP
 Tunneling: IPv4 or IPv6 GTP-U (GTPv1 bearer/user channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
Gxc Interface
This signaling interface supports the transfer of policy control and charging rules information (QoS) between the Bearer
Binding and Event Reporting Function (BBERF) on the S-GW and a Policy and Charging Rules Function (PCRF)
server.
Supported protocols:
 Transport Layer: TCP or SCTP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
Gz Interface
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S-GW Network Deployment(s) ▀
The Gz reference interface enables offline accounting functions on the S-GW. The S-GW collects charging information
for each mobile subscriber UE pertaining to the radio network usage. The Gz interface and offline accounting functions
are used primarily in roaming scenarios where the foreign P-GW does not support offline charging.
Supported protocols:
 Transport Layer: TCP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
Rf Interface
The Diameter Rf interface (3GPP 32.240) is used for offline (post-paid) charging between the Charging Trigger
Function (CTF, S-GW) and the Charging Data Function (CDF). It follows the Diameter base protocol state machine for
accounting (RFC 3588) and includes support for IMS specific AVPs (3GPP TS 32.299)
Supported protocols:
 Transport Layer: TCP or SCTP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
Figure 7.
335363.jpg
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P-GW Network Deployment(s)
This section describes the supported interfaces and the deployment scenarios of a PDN Gateway.
PDN Gateway in the E-UTRAN/EPC Network
The following figure displays the specific network interfaces supported by the P-GW. Refer to Supported Logical
Network Interfaces (Reference Points) for detailed information about each interface.
Figure 8.
Supported P-GW Interfaces in the E-UTRAN/EPC Network
The following figure displays a sample network deployment of a P-GW, including all of the interface connections with
other 3GPP Evolved-UTRAN/Evolved Packet Core network devices.
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Figure 9.
P-GW in the E-UTRAN/EPC Network
Supported Logical Network Interfaces (Reference Points)
The P-GW provides the following logical network interfaces in support of E-UTRAN/EPC network:
S5/S8 Interface
This reference point provides tunneling and management between the S-GW and the P-GW, as defined in 3GPP TS
23.401 and TS 23.402. The S8 interface is an inter-PLMN reference point between the S-GW and the P-GW used
during roaming scenarios. The S5 interface is used between an S-GW and P-GW located within the same administrative
domain (non-roaming). It is used for S-GW relocation due to UE mobility and if the S-GW needs to connect to a noncollocated P-GW for the required PDN connectivity.
Supported protocols
 Transport Layer: UDP, TCP
 Tunneling:
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 GTP: GTPv2-C (signaling channel), GTPv1-U (bearer channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
S6b Interface
This reference point, between a P-GW and a 3GPP AAA server/proxy, is used for mobility-related authentication. It
may also be used to retrieve and request parameters related to mobility and to retrieve static QoS profiles for UEs (for
non-3GPP access) in the event that dynamic PCC is not supported.
From Release 12.2 onwards, the S6b interface has been enhanced to pass on the UE assigned IPv6 address (IPv6 prefix
and IPv6 interface ID) to the AAA server. S6b interface also has support for Framed-IPv6-Pool, Framed IP Pool, and
served party IP address AVPs based IP allocation. With this support, based on the Pool name and APN name received
from AAA server, the selection of a particular IP pool from the configuration is made for assigning the IP address.
The S6b interface on the P-GW or GGSN can be manually disabled to stop all message traffic to the 3GPP AAA during
overload conditions. When the interface is disabled, the system uses locally configured APN-specific parameters
including: Framed-Pool, Framed-IPv6-Pool, Idle-Timeout, Charging-Gateway-Function-Host, Server-Name (P-CSCF
FQDN). This manual method is used when the HSS/3GPP AAA is in overload condition to allow the application to
recover and mitigate the impact to subscribers
Release 12.3 onwards, the IPv6 address reporting through Authorization-Authentication-Request (AAR) towards the
S6b interface is no longer a default feature. It is now configurable through the CLI.
Another enhancement on S6b interface support is the new S6b retry-and-continue functionality that creates an automatic
trigger in the GGSN and P-GW to use the locally configured APN profile upon receipt of any uniquely defined
Diameter error code on the S6b interface for an Authorization-Authentication-Request (AA-R) only. This procedure
would be utilized in cases where a protocol, transient, or permanent error code is returned from the both the pri mary and
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secondary AAA to the GGSN or P-GW. In case of retry-and-continue functionality, P-GW should query from DNS
server if it is configured in APN. S6b failure handling continues the data call. This behavior is only applicable to the
aaa-custom15 Diameter dictionary.
Important: The S6b interface can be disabled via the CLI in the event of a long-term AAA outage.
Supported protocols:
 Transport Layer: TCP, SCTP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
SGi Interface
This reference point provides connectivity between the P-GW and a packet data network (3GPP TS 23.401). This
interface can provide access to a variety of network types including an external public or private PDN and/or an internal
IMS service provisioning network.
Supported protocols:
 Transport Layer: TCP, UDP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
Gx Interface
This signalling interface supports the transfer of policy control and charging rules information (QoS) between the Policy
and Charging Enforcement Function (PCEF) on the P-GW and a Policy and Charging Rules Function (PCRF) server
(3GPP TS 23.401).
Supported protocols:
 Transport Layer: TCP, SCTP
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 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
For more information on the Gx interface, refer to Dynamic Policy Charging Control (Gx Reference Interface) in the
P-GW Features and Functionality - Base Software section of this chapter.
Gy Interface
The Gy reference interface enables online accounting functions on the P-GW in accordance with 3GPP Release 8 and
Release 9 specifications.
Supported protocols:
 Transport Layer: TCP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
For more information on the Gy interface and online accounting, refer to Gy Interface Support in the P-GW Features
and Functionality - Base Software section of this chapter.
Gz Interface
The Gz reference interface enables offline accounting functions on the P-GW. The P-GW collects charging information
for each mobile subscriber UE pertaining to the radio network usage.
Supported protocols:
 Transport Layer: TCP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
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Gn/Gp Interface
This reference point provides tunneling and management between the P-GW and the SGSN during handovers between
the EPS and 3GPP 2G and/or 3G networks (3GPP TS 29.060). For more information on the Gn/Gp interface, refer to
Gn/Gp Handoff Support in the P-GW Features and Functionality - Base Software section of this chapter.
Supported protocols
 Transport Layer: UDP, TCP
 Tunneling: GTP: GTP-C (signaling channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
Rf Interface
The Rf interface enables offline accounting functions on the P-GW in accordance with 3GPP Release 8 and Release 9
specifications. The P-GW collects charging information for each mobile subscriber UE pertaining to the radio network
usage.
Supported protocols:
 Transport Layer: TCP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
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PDN Gateway Supporting eHRPD to E-UTRAN/EPC Connectivity
The following figure displays the specific network interfaces supported by the P-GW in an eHRPD network. Refer to
Supported Logical Network Interfaces (Reference Points) for detailed information about each interface.
Figure 10.
P-GW Interfaces Supporting eHRPD to E-UTRAN/EPC Connectivity
The following figure displays a sample network deployment of a P-GW in an eHRPD Network, including all of the
interface connections with other 3GPP Evolved-UTRAN/Evolved Packet Core network devices.
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Figure 11.
P-GW in the E-UTRAN/EPC Network Supporting the eHRPD Network
Supported Logical Network Interfaces (Reference Points)
The P-GW provides the following logical network interfaces in support of eHRPD to E-UTRAN/EPC connectivity:
S5/S8 Interface
This reference point provides tunneling and management between the S-GW and the P-GW, as defined in 3GPP TS
23.401. The S8 interface is an inter-PLMN reference point between the S-GW and the P-GW used during roaming
scenarios. The S5 interface is used between an S-GW and P-GW located within the same administrative domain (nonroaming). It is used for S-GW relocation due to UE mobility and if the S-GW needs to connect to a non-collocated PGW for the required PDN connectivity.
Supported protocols:
 Transport Layer: UDP, TCP
 Tunneling:
 GTP: IPv4 or IPv6 GTP-C (signaling channel) and GTP-U (bearer channel)
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
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S2a Interface
This reference point supports the bearer interface by providing signaling and mobility support between a trusted non3GPP access point (HSGW) and the PDN Gateway. It is based on Proxy Mobile IP but also supports Client Mobile IPv4
FA mode which allows connectivity to trusted non-3GPP IP access points that do not support PMIP.
Supported protocols:
 Transport Layer: UDP, TCP
 Tunneling: GRE IPv6
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
S6b Interface
This reference point, between a P-GW and a 3GPP AAA server/proxy, is used for mobility-related authentication. It
may also be used to retrieve and request parameters related to mobility and to retrieve static QoS profiles for UEs (for
non-3GPP access) in the event that dynamic PCC is not supported.
From Release 12.2 onwards, the S6b interface has been enhanced to pass on the UE assigned IPv6 address (IPv6 prefix
and IPv6 interface ID) to the AAA server. S6b interface also has support for Framed-IPv6-Pool, Framed IP Pool, and
served party IP address AVPs based IP allocation. With this support, based on the Pool name and APN name received
from AAA server, the selection of a particular IP pool from the configuration is made for assigning the IP address.
The S6b interface on the P-GW or GGSN can be manually disabled to stop all message traffic to the 3GPP AAA during
overload conditions. When the interface is disabled, the system uses locally configured APN-specific parameters
including: Framed-Pool, Framed-IPv6-Pool, Idle-Timeout, Charging-Gateway-Function-Host, Server-Name (P-CSCF
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FQDN). This manual method is used when the HSS/3GPP AAA is in overload condition to allow the application to
recover and mitigate the impact to subscribers
Release 12.3 onwards, the IPv6 address reporting through Authorization-Authentication-Request (AAR) towards the
S6b interface is no longer a default feature. It is now configurable through the CLI.
Another enhancement on S6b interface support is the new S6b retry-and-continue functionality that creates an automatic
trigger in the GGSN and P-GW to use the locally configured APN profile upon receipt of any uniquely defined
Diameter error code on the S6b interface for an Authorization-Authentication-Request (AA-R) only. This procedure
would be utilized in cases where a protocol, transient, or permanent error code is returned from the both the primary and
secondary AAA to the GGSN or P-GW. In case of retry-and-continue functionality, P-GW should query from DNS
server if it is configured in APN. S6b failure handling continues the data call. This behavior is only applicable to the
aaa-custom15 Diameter dictionary.
Important: The S6b interface can be disabled via the CLI in the event of a long-term AAA outage.
Supported protocols:
 Transport Layer: TCP, SCTP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
SGi Interface
This reference point provides connectivity between the P-GW and a packet data network. This interface can provide
access to a variety of network types including an external public or private PDN and/or an internal IMS service
provisioning network.
Supported protocols:
 Transport Layer: TCP, UDP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
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Gx Interface
This signalling interface supports the transfer of policy control and charging rules information (QoS) between the Policy
and Charging Enforcement Function (PCEF) on the P-GW and a Policy and Charging Rules Function (PCRF) server
(3GPP TS 23.401).
Supported protocols:
 Transport Layer: TCP, SCTP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
For more information on the Gx interface, refer to Dynamic Policy Charging Control (Gx Reference Interface) in the PGW Features and Functionality - Base Software section of this chapter.
Rf Interface
The Rf reference interface enables offline accounting functions on the P-GW in accordance with 3GPP Release 8 and
Release 9 specifications. The P-GW collects charging information for each mobile subscriber UE pertaining to the radio
network usage.
Supported protocols:
 Transport Layer: TCP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
For more information on Rf accounting, refer to the section in the P-GW Features and Functionality - Base Software
section of this chapter.
Gy Interface
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The Gy reference interface enables online accounting functions on the P-GW in accordance with 3GPP Release 8 and
Release 9 specifications.
Supported protocols:
 Transport Layer: TCP
 Network Layer: IPv4, IPv6
 Data Link Layer: ARP
 Physical Layer: Ethernet
For more information on the Gy interface and online accounting, refer to Gy Interface Support in the P-GW Features
and Functionality - Base Software section of this chapter.
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S-GW Features and Functionality - Base Software
Important: The SAEGW supports all of these features if an S-GW service is assigned to the SAEGW service.
This section describes the features and functions supported by default in the base software for the S-GW service and do
not require any additional licenses to implement the functionality.
Important: To configure the basic service and functionality on the system for the S-GW service, refer to the
configuration examples provided in the Serving Gateway Administration Guide.
The following features are supported and brief descriptions are provided in this section:
 ANSI T1.276 Compliance
 APN-level Traffic Policing
 Bulk Statistics Support
 Circuit Switched Fall Back (CSFB) Support
 Closed Subscriber Group Support
 Congestion Control
 Dedicated Bearer Timeout Support on the S-GW
 Downlink Delay Notification
 DSCP Ingress and Egress and DSCP Marking at the APN Profile
 Dynamic GTP Echo Timer
 Event Reporting
 Idle-mode Signaling Reduction Support
 IP Access Control Lists
 IPv6 Capabilities
 LIPA Support
 Location Reporting
 Management System Overview
 Multiple PDN Support
 Node Functionality GTP Echo
 Online/Offline Charging
 Operator Policy Support
 Peer GTP Node Profile Configuration Support
 P-GW Restart Notification Support
 QoS Bearer Management
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 Rf Diameter Accounting
 S-GW Session Idle Timer
 Subscriber Level Trace
 Threshold Crossing Alerts (TCA) Support
ANSI T1.276 Compliance
ANSI T1.276 specifies security measures for Network Elements (NE). In particular it specifies guidelines for password
strength, storage, and maintenance security measures.
ANSI T1.276 specifies several measures for password security. These measures include:
 Password strength guidelines
 Password storage guidelines for network elements
 Password maintenance, e.g. periodic forced password changes
These measures are applicable to the ASR 5x00 Platform and the Web Element Manager since both require password
authentication. A subset of these guidelines where applicable to each platform will be implemented. A known subset of
guidelines, such as certificate authentication, are not applicable to either product. Furthermore, the platforms support a
variety of authentication methods such as RADIUS and SSH which are dependent on external elements. ANSI T1.276
compliance in such cases will be the domain of the external element. ANSI T1.276 guidelines will only be implemented
for locally configured operators.
APN-level Traffic Policing
The S-GW now supports traffic policing for roaming scenarios where the foreign P-GW does not enforce traffic classes.
Traffic policing is used to enforce bandwidth limitations on subscriber data traffic. It caps packet bursts and data rates at
configured burst size and data rate limits respectively for given class of traffic.
Traffic Policing is based on RFC2698- A Two Rate Three Color Marker (trTCM) algorithm. The trTCM meters an IP
packet stream and marks its packets green, yellow, or red. A packet is marked red if it exceeds the Peak Information
Rate (PIR). Otherwise it is marked either yellow or green depending on whether it exceeds or doesn't exceed the
Committed Information Rate (CIR). The trTCM is useful, for example, for ingress policing of a service, where a peak
rate needs to be enforced separately from a committed rate.
Bulk Statistics Support
The system's support for bulk statistics allows operators to choose to view not o nly statistics that are of importance to
them, but also to configure the format in which it is presented. This simplifies the post -processing of statistical data
since it can be formatted to be parsed by external, back-end processors.
When used in conjunction with the Web Element Manager, the data can be parsed, archived, and graphed.
The system can be configured to collect bulk statistics (performance data) and send them to a collection server (called a
receiver). Bulk statistics are statistics that are collected in a group. The individual statistics are grouped by schema.
Following is a partial list of supported schemas:
 System: Provides system-level statistics
 Card: Provides card-level statistics
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 Port: Provides port-level statistics
 MAG: Provides MAG service statistics
 S-GW: Provides S-GW node-level service statistics
 IP Pool: Provides IP pool statistics
 APN: Provides Access Point Name statistics
The system supports the configuration of up to four sets (primary/secondary) of receivers. Each set can be configured
with to collect specific sets of statistics from the various schemas. Statistics can be pulled manually from the system or
sent at configured intervals. The bulk statistics are stored on the receiver(s) in files.
The format of the bulk statistic data files can be configured by the user. Users can specify the format of the file name,
file headers, and/or footers to include information such as the date, system host name, system uptime, the IP address of
the system generating the statistics (available for only for headers and footers), and/or the time that the file was
generated.
The Cisco Web Element Manager is capable of further processing the statistics data through XML parsing, archiving,
and graphing.
The Bulk Statistics Server component of the Web Element Manager parses collected statistics and stores the information
in its PostgreSQL database. It can also generate XML output and can send it to a Northbound NMS or an alternate bulk
statistics server for further processing.
Additionally, the Bulk Statistics server can archive files to an alternative directory on the server. The directory can be on
a local file system or on an NFS-mounted file system on the Web Element Manager server.
Important: For more information on bulk statistic configuration, refer to the Configuring and Maintaining Bulk
Statistics chapter in the System Administration Guide.
Circuit Switched Fall Back (CSFB) Support
Circuit Switched Fall Back (CSFB) enables the UE to camp on an EUTRAN cell and originate or terminate voice calls
through a forced switchover to the circuit switched (CS) domain or other CS-domain services (for example, Location
Services (LCS) or supplementary services). Additionally, SMS delivery via the CS core network is realized without
CSFB. Since LTE EPC networks were not meant to directly anchor CS connections, when any CS voice services are
initiated, any PS based data activities on the EUTRAN network will be temporarily suspended (either the data transfer is
suspended or the packet switched connection is handed over to the 2G/3G network).
CSFB provides an interim solution for enabling telephony and SMS services for LTE operators that do not plan to
deploy IMS packet switched services at initial service launch.
The S-GW supports CSFB messaging over the S11 interface over GTP-C. Supported messages are:
 Suspend Notification
 Suspend Acknowledge
 Resume Notification
 Resume Acknowledgement
The S-GW forwards Suspend Notification messages towards the P-GW to suspend downlink data for non-GBR traffic;
the P-GW then drops all downlink packets. Later, when the UE finishes with CS services and moves back to E-UTRAN,
the MME sends a Resume Notification message to the S-GW which forwards the message to the P-GW. The downlink
data traffic then resumes.
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Closed Subscriber Group Support
The S-GW supports the following Closed Subscriber Group (CSG) Information Elements (IEs) and Call Detail Record:
 User CSG Information (UCI) IE in S5/S8
 CSG Information Reporting Action IE and functionality in S5/S8
 An SGW-CDR that includes a CSG record
Congestion Control
The congestion control feature allows you to set policies and thresholds and specify how the system reacts when faced
with a heavy load condition.
Congestion control monitors the system for conditions that could potentially degrade performance when the system is
under heavy load. Typically, these conditions are temporary (for example, high CPU or memory utilizat ion) and are
quickly resolved. However, continuous or large numbers of these conditions within a specific time interval may have an
impact the system’s ability to service subscriber sessions. Congestion control helps identify such conditions and invokes
policies for addressing the situation.
Congestion control operation is based on configuring the following:
 Congestion Condition Thresholds: Thresholds dictate the conditions for which congestion control is enabled
and establish limits for defining the state of the system (congested or clear). These thresholds function in a way
similar to operational thresholds that are configured for the system as described in the Thresholding
Configuration Guide. The primary difference is that when congestion thresholds are reached, a service
congestion policy and an SNMP trap, starCongestion, are generated.
A threshold tolerance dictates the percentage under the configured threshold that must be reached in order for
the condition to be cleared. An SNMP trap, starCongestionClear, is then triggered.
 Port Utilization Thresholds: If you set a port utilization threshold, when the average utilization of all
ports in the system reaches the specified threshold, congestion control is enabled.
 Port-specific Thresholds: If you set port-specific thresholds, when any individual port-specific
threshold is reached, congestion control is enabled system-wide.
 Service Congestion Policies: Congestion policies are configurable for each service. These policies dictate how
services respond when the system detects that a congestion condition threshold has been crossed.
Important: For more information on congestion control, refer to the Congestion Control appendix in the System
Administration Guide.
Dedicated Bearer Timeout Support on the S-GW
The SAE-GW has been enhanced to support a bearer inactivity timeout for GBR and non -GBR S-GW bearer type
sessions per Qos Class Identifier (QCI). This enables the deletion of bearers experiencing less data traffic than the
configured threshold value. Operators now can configure a bearer inactivity timeout for GBR and non-GBR bearers for
more efficient use of system resources.
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Downlink Delay Notification
This feature is divided between the following:
 Value Handling
 Throttling
 EPS Bearer ID and ARP Support
Value Handling
This feature provides for the handling of delay value information elements (IEs) at the S-GW. When a delay value is
received at the S-GW from a particular MME, the S-GW delays sending data notification requests for all idle calls
belonging to that particular MME. Once the timer expires, requests can be sent. The delay value at the S-GW is
determined by the factor received in the delay value IE (as a part of either a Modify Bearer Request or a Data Downlink
Notification Request) and a hard-coded base factor of 50 ms at the S-GW
Throttling
This feature provides additional controls allowing the S-GW to set factors that “throttle” the continuous sending and
receiving of DDN messages. A single command configures the throttling parameters supporting this feature,
A description of the ddn throttle command is located in the S-GW Service Configuration Mode Commands chapter
in the Command Line Interface Reference.
EPS Bearer ID and ARP Support
This feature allows support for Priority Paging support in the network. This is mainly needed for MPS subscriber
support. The paging priority in the paging message is set by MME based on ARP received in Downlink Data
Notification message.
In order to support MPS requirement for Priority Paging in the network for MPS subscriber, DDN message has been
enhanced to support passing ARP and EBI information. When the S-GW sends a Downlink Data Notification message,
it shall include both EPS Bearer ID and ARP. If the Downlink Data Notification is triggered by the arrival of downlink
data packets at the S-GW, the S-GW shall include the EPS Bearer ID and ARP associated with the bearer on which the
downlink data packet was received. If the Downlink Data Notification is triggered by the arrival of control signaling, the
S-GW shall include the EPS Bearer ID and ARP, if present in the control signaling. If the ARP is not present in the
control signaling, the S-GW shall include the ARP in the stored EPS bearer context. If multiple EPS Bearers IDs are
reported in the Downlink Data Notification message, the S-GW shall include all the EBI values and the ARP associated
with the bearer with the highest priority (lowest ARP value). For more information, see TS 23.401 (section 5.3.4.3) and
29.274 (section 7.2.11). Details are discussed in CR-859 of 3GPP specifications.
DSCP Ingress and Egress and DSCP Marking at the APN Profile
This feature provides operators with a configuration to set the DSCP value per APN profile, so different APNs can have
different DSCP markings as per QOS requirements for traffic carried by the APN. In addition, the qci-qos mapping
table is updated with the addition of a copy-outer for copying the DSCP value coming in the encapsulation header
from the S1u interface to the S5 interface and vice-versa.
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Dynamic GTP Echo Timer
The Dynamic GTP Echo Timer enables the eGTP and GTP-U services to better manage GTP paths during network
congestion. As opposed to the default echo timer which uses fixed intervals and retransmission timers, the dynamic echo
timer adds a calculated round trip timer (RTT) that is generated once a full request/response procedure has completed. A
multiplier can be added to the calculation for additional support during congestion periods.
For more information, refer to the Configuring the GTP Echo Timer section located in the Configuring Optional
Features on the eGTP S-GW section of the Serving Gateway Configuration chapter.
Event Reporting
The S-GW can be configured to send a stream of user event data to an external server. As users attach, detach, and move
throughout the network, they trigger signaling events, which are recorded and sent to an external server for processing.
Reported data includes failure reasons, nodes selected, user information (IMSI, IMEI, MSISDN), APN, failure codes (if
any) and other information on a per PDN-connection level. Event data is used to track the user status via near real time
monitoring tools and for historical analysis of major network events.
The S-GW Event Reporting appendix at the end of this guide describes the trigger mechanisms and event record
elements used for event reporting.
The SGW sends each event record in comma separated values (CSV) format. The record for each event is sent to the
external server within 60 seconds of its occurrence. The session-event-module command in the Context
Configuration mode allows an operator to set the method and destination for transferring event files, as well as the
format and handling characteristics of event files. For a detailed description of this command, refer to the Command
Line Interface Reference.
Idle-mode Signaling Reduction Support
The S-GW now supports Idle-mode Signaling Reduction (ISR) allowing for a control connection to exist between an SGW and an MME and S4-SGSN. The S-GW stores mobility management parameters from both nodes while the UE
stores session management contexts for both the EUTRAN and GERAN/UTRAN. This allows a UE, in idle mode, to
move between the two network types without needing to perform racking area update procedures, thus reducing the
signaling previously required. ISR support on the S-GW is embedded and no configuration is required however, an
optional feature license is required to enable this feature.
ISR support on the S-GW is embedded and no configuration is required, however, an optional feature license must be
purchased to enable this feature.
IP Access Control Lists
IP access control lists allow you to set up rules that control the flow of packets into and out of the system based on a
variety of IP packet parameters.
IP access lists, or Access Control Lists (ACLs) as they are commonly referred to, control the flow of packets into and
out of the system. They are configured on a per-context basis and consist of “rules” (ACL rules) or filters that control
the action taken on packets that match the filter criteria. Once configured, an ACL can be applied to any of the
following:
 An individual interface
 All traffic facilitated by a context (known as a policy ACL)
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 An individual subscriber
 All subscriber sessions facilitated by a specific context
Important: The S-GW supports interface-based ACLs only. For more information on IP access control lists,
refer to the IP Access Control Lists appendix in the System Administration Guide.
IPv6 Capabilities
IPv6 enables increased address efficiency and relieves pressures caused by rapidly approaching IPv4 address exhaustion
problem.
The S-GW platform offers the following IPv6 capabilities:
IPv6 Connections to Attached Elements
IPv6 transport and interfaces are supported on all of the following connections:
 Diameter Gxc policy signaling interface
 Diameter Rf offline charging interface
 Lawful Intercept (X1, X2 interfaces)
Routing and Miscellaneous Features
 OSPFv3
 MP-BGP v6 extensions
 IPv6 flows (Supported on all Diameter QoS and Charging interfaces as well as Inline Services (for example,
ECS, P2P detection, Stateful Firewall, etc.)
LIPA Support
A LIPA (Local IP Access) PDN is a PDN Connection for local IP access for a UE connected to a HeNB. The LIPA
architecture includes a Local Gateway (LGW) acting as an S-GW GTPv2 peer. The LGW is collocated with HeNB in
the operator network behaves as a PGW from SGW perspective. Once the default bearer for the LIPA PDN is
established, then data flows directly to the LGW and from there into the local network without traversing the core
network of the network operator.
In order to support millions of LIPA GTPC peers, S-GW memory management has been enhanced with regards to
GTPv2 procedures and as well as to support the maintenance of statistics per peer node.
Establishment of LIPA PDN follows a normal call flow similar to that of a normal PDN as per 23.401; the specification
does not distinguish between a LGW and a PGW call. As a result, the S-GW supports a new configuration option to
detect a LIPA peer. As a fallback mechanism, heuristic detection of LIPA peer based on data flow characteristics of a
LIPA call is also supported.
Whenever a peer is detected as a LIPA peer, the S-GW will disable GTPC echo mechanism towards that particular peer
and stop maintaining some statistics for that peer.
A configuration option in APN profile explicitly indicates that all the PDN’s for that APN are LIPA PDN’s, so all
GTPC peers on S5 for that APN are treated as LGW, and thus no any detection algorithm is applied to detect LGW.
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Location Reporting
Location reporting can be used to support a variety of applications including emergency calls, lawful intercept, and
charging. This feature reports both user location information (ULI).
ULI data reported in GTPv2 messages includes:
 TAI-ID: Tracking Area Identity
 MCC: MNC: Mobile Country Code, Mobile Network Code
 TAC: Tracking Area Code
The S-GW stores the ULI and also reports the information to the accounting framework. This may lead to generation of
Gz and Rf Interim records. The S-GW also forwards the received ULI to the P-GW. If the S-GW receives the UE time
zone IE from the MME, it forwards this IE towards the P-GW across the S5/S8 interface.
Management System Overview
The system's management capabilities are designed around the Telecommunications Management Network (TMN)
model for management - focusing on providing superior quality Network Element (NE) and element management
system (Web Element Manager) functions. The system provides element management applications th at can easily be
integrated, using standards-based protocols (CORBA and SNMPv1, v2), into higher-level management systems - giving
wireless operators the ability to integrate the system into their overall network, service, and business management
systems. In addition, all management is performed out-of-band for security and to maintain system performance.
Cisco's O+M module offers comprehensive management capabilities to the operators and enables them to operate the
system more efficiently. There are multiple ways to manage the system either locally or remotely using its out-of-band
management interfaces.
These include:
 Using the Command Line Interface (CLI)
 Remote login using Telnet, and Secure Shell (SSH) access to CLI through SPIO card's Ethernet manageme nt
interfaces
 Local login through the console port on the SPIO card via an RS-232 serial connection
 Using the Web Element Manager application
 Supports communications through 10 Base-T, 100 Base-TX, 1000 Base-TX, or
 1000Base-SX (optical gigabit Ethernet) Ethernet management interfaces on the SPIO
 Client-Server model supports any browser (such as, Microsoft Internet Explorer v6.0 and above or others)
 Supports Common Object Request Broker Architecture (CORBA) protocol and Simple Network Management
Protocol version 1 (SNMPv1) for fault management
 Provides complete Fault, Configuration, Accounting, Performance, and Security (FCAPS) capabilities
 Can be easily integrated with higher-level network, service, and business layer applications using the Object
Management Group's (OMG’s) Interface Definition Language (IDL)
The following figure demonstrates these various element management options and how they can be utilized within the
wireless carrier network.
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Figure 12.
Element Management Methods
Important: P-GW management functionality is enabled by default for console-based access. For GUI-based
management support, refer to the Web Element Manager section in this chapter.
Important: For more information on command line interface based management, refer to the Command Line
Interface Reference and P-GW Administration Guide.
Multiple PDN Support
Enables an APN-based user experience that enables separate connections to be allocated for different services including
IMS, Internet, walled garden services, or offdeck content services.
The Mobile Access Gateway (MAG) function on the S-GW can maintain multiple PDN or APN connections for the
same user session. The MAG runs a single node level Proxy Mobile IPv6 (PMIP) tunnel for all user sessions toward the
Local Mobility Anchor (LMA) function of the P-GW.
When a user wants to establish multiple PDN connections, the MAG brings up the multiple PDN connections over the
same PMIPv6 session to one or more P-GW LMAs. The P-GW in turn allocates separate IP addresses (Home Network
Prefixes) for each PDN connection and each one can run one or multiple EPC default and dedicated bearers. To request
the various PDN connections, the MAG includes a common MN-ID and separate Home Network Prefixes, APNs and a
Handover Indication Value equal to one in the PMIPv6 Binding Updates.
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Important: Up to 11 multiple PDN connections are supported.
Node Functionality GTP Echo
This feature helps exchange capabilities of two communicating GTP nodes, and uses the feature based on whether it is
supported by the other node.
This feature allows S-GW to exchange its capabilities (MABR, PRN, NTSR) with the peer entities through ECHO
messages. By this, if both the peer nodes support some common features, then they can make use of new messages to
communicate with each other.
With new “node features” IE support in ECHO request/response message, each node can send its supported features
(MABR, PRN, NTSR). This way, S-GW can learn the peer node’s supported features. S-GW’s supported features can
be configured by having some configuration at the service level.
If S-GW wants to use new message, such as P-GW Restart Notification, then S-GW should check if the peer node
supports this new feature or not. If the peer does not support it, then S-GW should fall back to old behavior.
If S-GW receives a new message from the peer node, and if S-GW does not support this new message, then S-GW
should ignore it. If S-GW supports the particular feature, then it should handle the new message as per the specification.
Online/Offline Charging
The Cisco EPC platforms support offline charging interactions with external OCS and CGF/CDF servers. To provide
subscriber level accounting, the Cisco EPC platform supports integrated Charging Transfer Function (CTF) and
Charging Data Function (CDF) / Charging Gateway Function (CGF). Each gateway uses Charging-IDs to distinguish
between default and dedicated bearers within subscriber sessions.
The ASR 5x00 platform offers a local directory to enable temporary file storage and buffer charging records in
persistent memory located on a pair of dual redundant RAID hard disks. Each drive includes 147GB of storage and up
to 100GB of capacity is dedicated to storing charging records. For increased efficiency it also possible to enable file
compression using protocols such as GZIP.
The offline charging implementation offers built-in heart beat monitoring of adjacent CGFs. If the Cisco P-GW has not
heard from the neighboring CGF within the configurable polling interval, it will automatically buffer the charging
records on the local drives until the CGF reactivates itself and is able to begin pulling the cached charging records.
Online: Gy Reference Interface
The P-GW supports a Policy Charging Enforcement Function (PCEF) to enable Flow Based Bearer Charging (FBC) via
the Gy reference interface to adjunct Online Charging System (OCS) servers. The Gy interface provides a standardized
Diameter interface for real-time content-based charging of data services. It is based on the 3GPP standards and relies on
quota allocation. The Gy interface provides an online charging interface that works with the ECS Deep Packet
Inspection feature. With Gy, customer traffic can be gated and billed. Both time- and volume-based charging models are
supported.
Offline: Gz Reference Interface
The Cisco P-GW and S-GW support 3GPP Release 8 compliant offline charging as defined in TS 32.251,TS 32.297 and
32.298. Whereas the S-GW generates SGW-CDRs to record subscriber level access to PLMN resources, the P-GW
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creates PGW-CDRs to record user access to external networks. Additionally when Gn/Gp interworking with SGSNs is
enabled, the GGSN service on the P-GW records G-CDRs to record user access to external networks.
To provide subscriber level accounting, the Cisco S-GW supports integrated Charging Transfer Function (CTF) and
Charging Data Function (CDF). Each gateway uses Charging-IDs to distinguish between default and dedicated bearers
within subscriber sessions.
The Gz reference interface between the CDF and CGF is used to transfer charging records via the GTPP protocol. In a
standards based implementation, the CGF consolidates the charging records and transfers them via an FTP or SFTP
connection over the Bm reference interface to a back-end billing mediation server. The Cisco EPC gateways also offer
the ability to transfer charging records between the CDF and CGF serve via FTP or SFTP. CDR records include
information such as Record Type, Served IMSI, ChargingID, APN Name, TimeStamp, Call Duration, Served MSISDN,
PLMN-ID, etc.
Offline: Rf Reference Interface
Cisco EPC platforms also support the Rf reference interface to enable direct transfer of charging files from the CTF
function of the S-GW to external CDF or CGF servers. This interface uses Diameter Accounting Requests (Start, Stop,
Interim, and Event) to transfer charging records to the CDF/CGF. Each gateway relies on triggering conditions for
reporting chargeable events to the CDF/CGF. Typically as EPS bearers are activated, modified or deleted, charging
records are generated. The EPC platforms include information such as Subscription -ID (IMSI), Charging-ID (EPS
bearer identifier) and separate volume counts for the uplink and downlink traffic.
Operator Policy Support
The operator policy provides mechanisms to fine tune the behavior of subsets of subscribers above and beyond the
behaviors described in the user profile. It also can be used to control the behavior of visiting subscribers in roaming
scenarios, enforcing roaming agreements and providing a measure of local protection against foreign subscribers.
An operator policy associates APNs, APN profiles, an APN remap table, and a call-control profile to ranges of IMSIs.
These profiles and tables are created and defined within their own configuration modes to generate sets of rules and
instructions that can be reused and assigned to multiple policies. In this manner, an operator policy manages the
application of rules governing the services, facilities, and privileges available to subscribers. These policies can override
standard behaviors and provide mechanisms for an operator to get around the limitations of other infrastructure
elements, such as DNS servers and HSSs.
The operator policy configuration to be applied to a subscriber is selected o n the basis of the selection criteria in the
subscriber mapping at attach time. A maximum of 1,024 operator policies can be configured. If a UE was associated
with a specific operator policy and that policy is deleted, the next time the UE attempts to access the policy, it will
attempt to find another policy with which to be associated.
A default operator policy can be configured and applied to all subscribers that do not match any of the per-PLMN or
IMSI range policies.
The S-GW uses operator policy to set the Accounting Mode - GTPP (default), RADIUS/Diameter or none. However,
the accounting mode configured for the call-control profile will override this setting.
Changes to the operator policy take effect when the subscriber re-attaches and subsequent EPS Bearer activations.
Peer GTP Node Profile Configuration Support
Provides flexibility to the operators to have different configuration for GTP-C and Lawful Intercept, based on the type
of peer or the IP address of the peer
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Peer profile feature allows flexible profile based configuration to accommodate growing requirements of customizable
parameters with default values and actions for peer nodes of S-GW. With this feature, configuration of GTP-C
parameters and disabling/enabling of Lawful Intercept per MCC/MNC or IP address based on rules defined.
A new framework of peer-profile and peer-map is introduced. Peer-profile configuration captures the GTP-C specific
configuration and/or Lawful Intercept enable/disable configuration. GTP-C configuration covers GTP-C retransmission
(maximum number of retries and retransmission timeout) and GTP echo configuration. Peer-map configuration matches
the peer-profile to be applied to a particular criteria. Peer-map supports criteria like MCC/MNC (PLMN-ID) of the peer
or IP-address of the peer. Peer-map can then be associated with S-GW service.
Intent of this feature is to provide flexibility to operators to configure a profile which can be applied to a specific set of
peers. For example, have a different retransmission timeout for foreign peers as compared to home peers.
P-GW Restart Notification Support
This procedure optimizes the amount of signaling involved on S11/S4 interface when P-GW failure is detected.
P-GW Restart Notification Procedure is a standards-based procedure supported on S-GW to notify detection of P-GW
failure to MME/S4-SGSN. P-GW failure detection will be done at S-GW when it detects that the P-GW has restarted
(based on restart counter received from the restarted P-GW) or when it detects that P-GW has failed but not restarted
(based on path failure detection). When an S-GW detects that a peer P-GW has restarted, it shall locally delete all PDN
connection table data and bearer contexts associated with the failed P-GW and notify the MME via P-GW Restart
Notification. S-GW will indicate in the echo request/response on S11/S4 interface that the P-GW Restart Notification
procedure is supported.
P-GW Restart Notification Procedure is an optional procedure and is invoked only if both the peers, MME/S4-SGSN
and S-GW, support it. This procedure optimizes the amount of signaling involved on S11/S4 interface when P-GW
failure is detected. In the absence of this procedure, S-GW will initiate the Delete procedure to clean up all the PDNs
anchored at that failed P-GW, which can lead to flooding of GTP messages on S11/S4 if there are multiple PDNs using
that S-GW and P-GW.
QoS Bearer Management
Provides a foundation for contributing towards improved Quality of User Experience (QoE) by enabling deterministic
end-to-end forwarding and scheduling treatments for different services or classes of applications pursuant to their
requirements for committed bandwidth resources, jitter and delay. In this way, each application receives the service
treatment that users expect.
An EPS bearer is a logical aggregate of one or more Service Data Flows (SDFs), running between a UE and a P-GW in
case of GTP-based S5/S8, and between a UE and HSGW in case of PMIP-based S2a connection. An EPS bearer is the
level of granularity for bearer level QoS control in the EPC/E-UTRAN. The Cisco P-GW maintains one or more Traffic
Flow Templates (TFTs) in the downlink direction for mapping inbound Service Data Flows (SDFs) to EPS bearers. The
P-GW maps the traffic based on the downlink TFT to the S5/S8 bearer. The Cisco P-GW offers all of the following
bearer-level aggregate constructs:
QoS Class Identifier (QCI): An operator provisioned value that controls bearer level packet forwarding treatments (for
example, scheduling weights, admission thresholds, queue management thresholds, link layer protocol configuration,
etc). Cisco EPC gateways also support the ability to map the QCI values to DiffServ codepoints in the outer GTP tunnel
header of the S5/S8 connection. Additionally, the platform also provides configurable parameters to copy the DSCP
marking from the encapsulated payload to the outer GTP tunnel header.
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Important: The SAEGW does not support non-standard QCI values. QCI values 1 through 9 are standard values
defined in 3GPP TS 23.203; the SAEGW supports these standard values.
Guaranteed Bit Rate (GBR): A GBR bearer is associated with a dedicated EPS bearer and provides a guaranteed
minimum transmission rate in order to offer constant bit rate services for applications such as interactive voice that
require deterministic low delay service treatment.
Maximum Bit Rate (MBR): The MBR attribute provides a configurable burst rate that limits the bit rate that can be
expected to be provided by a GBR bearer (e.g. excess traffic may get discarded by a rate shaping function). The MBR
may be greater than or equal to the GBR for a given dedicated EPS bearer.
Aggregate Maximum Bit Rate (AMBR): AMBR denotes a bit rate of traffic for a group of bearers destined for a
particular PDN. The Aggregate Maximum Bit Rate is typically assigned to a group of Best Effort service data flows
over the Default EPS bearer. That is, each of those EPS bearers could potentially utilize the entire AMBR, e.g. when the
other EPS bearers do not carry any traffic. The AMBR limits the aggregate bit rate that can be expected to be provided
by the EPS bearers sharing the AMBR (e.g. excess traffic may get discarded by a rate shaping function). AMBR applies
to all Non-GBR bearers belonging to the same PDN connection. GBR bearers are outside the scope of AMBR.
Policing: The Cisco P-GW offers a variety of traffic conditioning and bandwidth management capabilities. These tools
enable usage controls to be applied on a per-subscriber, per-EPS bearer or per-PDN/APN basis. It is also possible to
apply bandwidth controls on a per-APN AMBR capacity. These applications provide the ability to inspect and maintain
state for user sessions or Service Data Flows (SDFs) within them using shallow L3/L4 analysis or high touch deep
packet inspection at L7. Metering of out-of-profile flows or sessions can result in packet discards or reducing the DSCP
marking to Best Effort priority.
Rf Diameter Accounting
Provides the framework for offline charging in a packet switched domain. The gateway support nodes use the Rf
interface to convey session related, bearer related or service specific charging records to the CGF and billing domain for
enabling charging plans.
The Rf reference interface enables offline accounting functions on the HSGW in accordance with 3GPP Release 8
specifications. In an LTE application the same reference interface is also supported on the S-GW and P-GW platforms.
The Cisco gateways use the Charging Trigger Function (CTF) to transfer offline accounting records via a Diameter
interface to an adjunct Charging Data Function (CDF) / Charging Gateway Function (CGF). The HSGW and Serving
Gateway collect charging information for each mobile subscriber UE pertaining to the radio network usage while the PGW collects charging information for each mobile subscriber related to the external data network usage.
The S-GW collects information per-user, per IP CAN bearer or per service. Bearer charging is used to collect charging
information related to data volumes sent to and received from the UE and categorized by QoS traffic class. Users can be
identified by MSISDN or IMSI.
Flow Data Records (FDRs) are used to correlate application charging data with EPC bearer usage information. The
FDRs contain application level charging information like service identifiers, rating groups, IMS charging identifiers that
can be used to identify the application. The FDRs also contain the authorized QoS information (QCI) that was assigned
to a given flow. This information is used correlate charging records with EPC bearers.
S-GW Session Idle Timer
A session idle timer has been implemented on the S-GW to remove stale session in those cases where the session is
removed on the other nodes but due to some issue remains on the S-GW. Once configured, the session idle timer will
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tear down those sessions that remain idle for longer than the configured time limit. The implementation of the session
idle timer allows the S-GW to more effectively utilize system capacity.
Important: The session idle timer feature will not work if the Fast Data Path feature is enabled.
Subscriber Level Trace
Provides a 3GPP standards-based session level trace function for call debugging and testing new functions and access
terminals in an LTE environment.
As a complement to Cisco's protocol monitoring function, the S-GW supports 3GPP standards based session level trace
capabilities to monitor all call control events on the respective monitored interfaces including S1 -U, S11, S5/S8, and
Gxc. The trace can be initiated using multiple methods:
 Management initiation via direct CLI configuration
 Management initiation at HSS with trace activation via authentication response messages over S6a reference
interface
 Signaling based activation through signaling from subscriber access terminal
Note: Once the trace is provisioned it can be provisioned through the access cloud via various signaling interfaces.
The session level trace function consists of trace activation followed by triggers. The EPC network element buffers the
trace activation instructions for the provisioned subscriber in memory using camp-on monitoring. Trace files for active
calls are buffered as XML files using non-volatile memory on the local dual redundant hard drives on the ASR 5x00
platform. The Trace Depth defines the granularity of data to be traced. Six levels are defined including Maximum,
Minimum and Medium with ability to configure additional levels based on vendor extensions.
All call control activity for active and recorded sessions is sent to an off-line Trace Collection Entity (TCE) using a
standards-based XML format over an FTP or secure FTP (SFTP) connection. In the current release the IPv4 interfaces
are used to provide connectivity to the TCE. Trace activation is based on IMSI or IMEI.
Once a subscriber level trace request is activated it can be propagated via the S5/S8 signaling to provision the
corresponding trace for the same subscriber call on the P-GW. The trace configuration will only be propagated if the PGW is specified in the list of configured Network Element types received by the S-GW. Trace configuration can be
specified or transferred in any of the following message types:
 S11: Create Session Request
 S11: Trace Session Activation
 S11: Modify Bearer Request
As subscriber level trace is a CPU intensive activity the maximum number of concurrently monitored trace sessions per
Cisco P-GW or S-GW is 32. Use in a production network should be restricted to minimize the impact on existing
services.
Threshold Crossing Alerts (TCA) Support
Thresholding on the system is used to monitor the system for conditions that could potentially cause errors or outage.
Typically, these conditions are temporary (i.e high CPU utilization, or packet collisions on a network) and are quickly
resolved. However, continuous or large numbers of these error conditions within a specific time interval may be
indicative of larger, more severe issues. The purpose of thresholding is to help identify potentially severe conditions so
that immediate action can be taken to minimize and/or avoid system downtime.
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The system supports Threshold Crossing Alerts for certain key resources such as CPU, memory, IP pool addresses, etc.
With this capability, the operator can configure threshold on these resources whereby, should the resource depletion
cross the configured threshold, a SNMP Trap would be sent.
The following thresholding models are supported by the system:
 Alert: A value is monitored and an alert condition occurs when the value reaches or exceeds the configured high
threshold within the specified polling interval. The alert is generated then generated and/or sent at the end of
the polling interval.
 Alarm: Both high and low threshold are defined for a value. An alarm condition occurs when th e value reaches
or exceeds the configured high threshold within the specified polling interval. The alert is generated then
generated and/or sent at the end of the polling interval.
Thresholding reports conditions using one of the following mechanisms:
 SNMP traps: SNMP traps have been created that indicate the condition (high threshold crossing and clear) of
each of the monitored values.
Generation of specific traps can be enabled or disabled on the chassis. Ensuring that only important faults get
displayed. SNMP traps are supported in both Alert and Alarm modes.
 Logs: The system provides a facility called threshold for which active and event logs can be generated. As with
other system facilities, logs are generated Log messages pertaining to the condition o f a monitored value are
generated with a severity level of WARNING.
Logs are supported in both the Alert and the Alarm models.
 Alarm System: High threshold alarms generated within the specified polling interval are considered outstanding
until a the condition no longer exists or a condition clear alarm is generated. Outstanding alarms are reported to
the system's alarm subsystem and are viewable through the Alarm Management menu in the Web Element
Manager.
The Alarm System is used only in conjunction with the Alarm model.
Important: For more information on threshold crossing alert configuration, refer to the Thresholding
Configuration Guide.
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P-GW Features and Functionality - Base Software
Important: The SAEGW supports all of these features if a P-GW service is assigned to the SAEGW service.
This section describes the features and functions supported by default in the base software for the P-GW service and do
not require any additional licenses to implement the functionality.
Important: To configure the basic service and functionality on the system for the P-GW service, refer to the
configuration examples provided in the Packet Data Network Gateway Administration Guide.
This section describes the following features:
 3GPP R9 Volume Charging Over Gx
 AAA Server Groups
 ANSI T1.276 Compliance
 APN Support
 Assume Positive for Gy-based Quota Tracking
 Bulk Statistics Support
 Congestion Control
 Default and Dedicated EPC Bearers
 DHCP Support
 DHCPv6 Support
 Direct Tunnel Support
 DNS Support for IPv4IPv6 PDP Contexts
 Domain Based Flow Definitions
 DSCP Marking
 Dynamic GTP Echo Timer
 Dynamic Policy Charging Control (Gx Reference Interface)
 Enhanced Charging Service (ECS)
 GnGp Handoff Support
 IMS Emergency Bearer Handling
 IP Access Control Lists
 IP Address Hold Timers
 IPv6 Capabilities
 Local Break-Out
 Management System Overview
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 Mobile IP Registration Revocation
 MPLS EXP Marking of User Plane Traffic
 MTU Size PCO
 Multiple PDN Support
 Node Functionality GTP Echo
 Non-Optimized e-HRPD to Native LTE (E-UTRAN) Mobility Handover
 Online/Offline Charging
 Peer GTP Node Profile Configuration Support
 PMIPv6 Heartbeat
 Proxy Mobile IPv6 (S2a)
 QoS Bearer Management
 RADIUS Support
 SGW Restoration Support
 Source IP Address Validation
 SRVCC PS-to-CS Handover Indication Support
 Subscriber Level Trace
 Threshold Crossing Alerts (TCA) Support
 UE Time Zone Reporting
 Virtual APN Support
Important: To configure the basic service and functionality on the system for the P-GW service, refer to the
configuration examples provided in this guide.
3GPP R9 Volume Charging Over Gx
Also known as accumulated usage tracking over Gx, this 3GPP R9 enhancement provides a subset of the volume and
charging control functions defined in TS 29.212 based on usage quotas between a P-GW and PCRF. The quotas can be
assigned to the default bearer or any of the dedicated bearers for the PDN connection.
This feature enables volume reporting over Gx, which entails usage monitoring and reporting of the accumulated usage
of network resources on an IP-CAN session or service data flow basis. PCRF subscribes to the usage monitoring at
session level or at flow level by providing the necessary information to PCEF. PCEF in turn reports the usage to the
PCRF when the conditions are met. Based on the total network usage in real-time, the PCRF will have the information
to enforce dynamic policy decisions.
When usage monitoring is enabled, the PCEF can monitor the usage volume for the IP-CAN session, or applicable
service data flows, and report accumulated usage to the PCRF based on any of the following conditions:
 When a usage threshold is reached,
 When all PCC rules for which usage monitoring is enabled for a particular usage monitoring key are removed or
deactivated,
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 When usage monitoring is explicitly disabled by the PCRF,
 When an IP CAN session is terminated or,
 When requested by the PCRF.
Accumulated volume reporting can be measured by total volume, the uplink volume, or the downlink volume as
requested by the PCRF. When receiving the reported usage from the PCEF, the PCRF dedu cts the value of the usage
report from the total allowed usage for that IP-CAN session, usage monitoring key, or both as applicable.
AAA Server Groups
Value-added feature to enable VPN service provisioning for enterprise or MVNO customers. Enables each corporate
customer to maintain its own AAA servers with its own unique configurable parameters and custom dictionaries.
This feature provides support for up to 800 AAA server groups and 800 NAS IP addresses that can be provisioned
within a single context or across the entire chassis. A total of 128 servers can be assigned to an individual server group.
Up to 1,600 accounting, authentication and/or mediation servers are supported per chassis.
ANSI T1.276 Compliance
ANSI T1.276 specifies security measures for Network Elements (NE). In particular it specifies guidelines for p assword
strength, storage, and maintenance security measures.
ANSI T1.276 specifies several measures for password security. These measures include:
 Password strength guidelines
 Password storage guidelines for network elements
 Password maintenance, e.g. periodic forced password changes
These measures are applicable to the ASR 5x00 and the Web Element Manager since both require password
authentication. A subset of these guidelines where applicable to each platform will be implemented. A known subset of
guidelines, such as certificate authentication, are not applicable to either product. Furthermore, the platforms support a
variety of authentication methods such as RADIUS and SSH which are dependent on external elements. ANSI T1.276
compliance in such cases will be the domain of the external element. ANSI T1.276 guidelines will only be implemented
for locally configured operators.
APN Support
The P-GW's Access Point Name (APN) support offers several benefits:
 Extensive parameter configuration flexibility for the APN.
 Creation of subscriber tiers for individual subscribers or sets of subscribers within the APN.
 Virtual APNs to allow differentiated services within a single APN.
In StarOS v12.x and earlier, up to 1024 APNs can be configured in the P-GW. In StarOS v14.0 and later, up to 2048
APNs can be configured in the P-GW. An APN may be configured for any type of PDP context, i.e., PPP, IPv4, IPv6 or
both IPv4 and IPv6. Many dozens of parameters may be configured independently for each APN.
Here are a few highlights of what may be configured:
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 Accounting: RADIUS, GTPP or none. Server group to use. Charging characteristics. Interface with mediation
servers.
 Authentication: Protocol, such as, CHAP or PAP or none. Default username/password. Server group to use.
Limit for number of PDP contexts.
 Enhanced Charging: Name of rulebase to use, which holds the enhanced charging configuration (e.g., eG-CDR
variations, charging rules, prepaid/postpaid options, etc.).
 IP: Method for IP address allocation (e.g., local allocation by P-GW, Mobile IP, DHCP, etc.). IP address ranges,
with or without overlapping ranges across APNs.
 Tunneling: PPP may be tunneled with L2TP. IPv4 may be tunneled with GRE, IP-in-IP or L2TP. Loadbalancing across multiple tunnels. IPv6 is tunneled in IPv4. Additional tunneling techniques, such as, IPsec and
VLAN tagging may be selected by the APN, but are configured in the P-GW independently from the APN.
 QoS: IPv4 header ToS handling. Traffic rate limits for different 3GPP traffic classes. Mapping of R98 QoS
attributes to work around particular handset defections. Dynamic QoS renegotiation (described elsewhere).
After an APN is determined by the P-GW, the subscriber may be authenticated/authorized with an AAA server. The PGW allows the AAA server to return VSAs (Vendor Specific Attributes) that override any/all of the APN configuration.
This allows different subscriber tier profiles to be configured in the AAA server, and passed to the P-GW during
subscriber authentication/authorization.
Important: For more information on APN configuration, refer to the PDN Gateway Configuration chapter this
guide.
Assume Positive for Gy-based Quota Tracking
In the current implementation, the PCEF uses a Diameter based Gy interface to interact with the OCS and obtain quota
for each subscriber's data session. Now, the PCEF can retry the OCS after a configured amount of quota has been
utilized or after a configured amount of time. The quota value would be part of the dcca-service configuration, and
would apply to all subscribers using this dcca-service. The temporary quota will be specified in volume (MB) and/or
time (minutes) to allow for enforcement of both quota tracking mechanisms, individually or simultaneously.
When a user consumes the interim total quota or time configured for use during failure handling scenarios, the PCEF
shall retry the OCS server to determine if functionality has been restored. In the event that services have been restored,
quota assignment and tracking will proceed as per standard usage reporting procedures. Data used during the outage will
be reported to the OCS. In the event that the OCS services have not been restored, the PCEF should reallocate with the
configured amount of quota and time assigned to the user. The PCEF should report all accumulated used data back to
OCS when OCS is back online. If multiple retries and interim allocations occur, the PCEF shall report quota used during
all allocation intervals.
When the Gy interface is unavailable, the P-GW shall enter “assume positive” mode. Unique treatment is provided to
each subscriber type. Each functional application shall be assigned unique temporary quota volume amounts and time
periods based on a command-level AVP from the PCRF on the Gx interface. In addition, a configurable option has been
added to disable assume positive functionality for a subscriber group identified by a command-level AVP sent on the
Gx interface by the PCRF.
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Bulk Statistics Support
The system's support for bulk statistics allows operators to choose to view not only statistics that are of importance to
them, but also to configure the format in which it is presented. This simplifies the post -processing of statistical data
since it can be formatted to be parsed by external, back-end processors.
When used in conjunction with the Web Element Manager, the data can be parsed, archived, and graphed.
The system can be configured to collect bulk statistics (performance data) and send them to a col lection server (called a
receiver). Bulk statistics are statistics that are collected in a group. The individual statistics are grouped by schema.
Following is a list of supported schemas for P-GW:
 APN: Provides Access Point Name statistics
 Card: Provides card-level statistics
 Context: Provides context service statistics
 Diameter-acct: Provides Diameter Accounting statistics
 Diameter-auth: Provides Diameter Authentication statistics
 ECS: Provides Enhanced Charging Service statistics
 EGTPC: Provides Evolved GPRS Tunneling Protocol - Control message statistics
 FA: Provides FA service statistics
 GTPC: Provides GPRS Tunneling Protocol - Control message statistics
 GTPP: Provides GPRS Tunneling Protocol - Prime message statistics
 GTPU: Provides GPRS Tunneling Protocol - User message statistics
 HA: Provides HA service statistics
 IMSA: Provides IMS Authorization service statistics
 IP Pool: Provides IP pool statistics
 LMA: Provides Local Mobility Anchor service statistics
 P-GW: Provides P-GW node-level service statistics
 Port: Provides port-level statistics
 PPP: Provides Point-to-Point Protocol statistics
 RADIUS: Provides per-RADIUS server statistics
 System: Provides system-level statistics
The system supports the configuration of up to 4 sets (primary/secondary) of receivers. Each set can be configured with
to collect specific sets of statistics from the various schemas. Statistics can be pulled manually from the system or sent
at configured intervals. The bulk statistics are stored on the receiver(s) in files.
The format of the bulk statistic data files can be configured by the user. Users can specify the format of the file name,
file headers, and/or footers to include information such as the date, system host name, system uptime, the IP address of
the system generating the statistics (available for only for headers and footers), and/or the time that the file was
generated.
When the Web Element Manager is used as the receiver, it is capable of further processing the statistics data through
XML parsing, archiving, and graphing.
The Bulk Statistics Server component of the Web Element Manager parses collected statistics and stores the information
in the PostgreSQL database. If XML file generation and transfer is required, this element generates the XML output and
can send it to a Northbound NMS or an alternate bulk statistics server for further processing.
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Additionally, if archiving of the collected statistics is desired, the Bulk Statistics server writes the files to an alternative
directory on the server. A specific directory can be configured by the administrative user or the default directory can be
used. Regardless, the directory can be on a local file system or on an NFS-mounted file system on the Web Element
Manager server.
Important: For more information on bulk statistic configuration, refer to the Configuring and Maintaining Bulk
Statistics chapter in the System Administration Guide.
Congestion Control
The congestion control feature allows you to set policies and thresholds and specify how the system reacts when faced
with a heavy load condition.
Congestion control monitors the system for conditions that could potentially degrade performance when the system is
under heavy load. Typically, these conditions are temporary (for example, high CPU or memory utilization) and are
quickly resolved. However, continuous or large numbers of these conditions within a specific time interval may have an
impact the system’s ability to service subscriber sessions. Congestion control helps identify such conditions and invokes
policies for addressing the situation.
Congestion control operation is based on configuring the following:
 Congestion Condition Thresholds: Thresholds dictate the conditions for which congestion control is enabled
and establishes limits for defining the state of the system (congested or clear). These thresholds function in a
way similar to operation thresholds that are configured for the system as described in the Thresholding
Configuration Guide. The primary difference is that when congestion thresholds are reached, a service
congestion policy and an SNMP trap, starCongestion, are generated.
A threshold tolerance dictates the percentage under the configured threshold that must be reached in order for
the condition to be cleared. An SNMP trap, starCongestionClear, is then triggered.
 Port Utilization Thresholds: If you set a port utilization threshold, when the average utilization of all
ports in the system reaches the specified threshold, congestion control is enabled.
 Port-specific Thresholds: If you set port-specific thresholds, when any individual portspecific threshold is reached, congestion control is enabled system-wide.
 Service Congestion Policies: Congestion policies are configurable for each service. These policies
dictate how services respond when the system detects that a congestion condition threshold has been
crossed.
Important: For more information on congestion control, refer to the Congestion Control chapter in the System
Administration Guide.
Default and Dedicated EPC Bearers
Provides a foundation for contributing towards improved Quality of User Experience (QoE) by enabling deterministic
end-to-end forwarding and scheduling treatments for different services or classes of applications pursuant to their
requirements for committed bandwidth resources, jitter and delay. In this way, each application receives the service
treatment that users expect.
In the StarOS 9.0 release, the Cisco EPC core platforms support one or more EPS bearers (default plus dedicated). An
EPS bearer is a logical aggregate of one or more Service Data Flows (SDFs), running between a UE and a P-GW in the
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case of a GTP-based S5/S8 interface, and between a UE and HSGW (HRPD Serving Gateway) in case of a PMIP-based
S2a interface. In networks where GTP is used as the S5/S8 protocol, the EPS bearer constitutes a concatenation of a
radio bearer, S1-U bearer and an S5/S8 bearer anchored on the P-GW. In cases where PMIPv6 is used the EPS bearer is
concatenated between the UE and HSGW with IP connectivity between the HSGW and P-GW.
Note: This release supports only GTP-based S5/S8 and PMIPv6 S2a capabilities with no commercial support for
PMIPv6 S5/S8.
An EPS bearer uniquely identifies traffic flows that receive a common QoS treatment between a UE and P-GW in the
GTP-based S5/S8 design, and between a UE and HSGW in the PMIPv6 S2a approach. If different QoS scheduling
priorities are required between Service Data Flows, they should be assigned to separate EPS bearers. Packet filters are
signalled in the NAS procedures and associated with a unique packet filter identifier on a per-PDN connection basis.
One EPS bearer is established when the UE connects to a PDN, and that remains established throughout the lifetime of
the PDN connection to provide the UE with always-on IP connectivity to that PDN. That bearer is referred to as the
default bearer. A PDN connection represents a traffic flow aggregate between a mobile access terminal and an external
Packet Data Network (PDN) such as an IMS network, a walled garden application cloud or a back -end enterprise
network. Any additional EPS bearer that is established to the same PDN is referred to as a dedicated bearer. The EPS
bearer Traffic Flow Template (TFT) is the set of all 5-tuple packet filters associated with a given EPS bearer. The EPC
core elements assign a separate bearer ID for each established EPS bearer. At a given time a UE may have multiple
PDN connections on one or more P-GWs.
DHCP Support
The P-GW supports dynamic IP address assignment to subscriber IP PDN contexts using the Dynamic Host Control
Protocol (DHCP), as defined by the following standards:
 RFC 2131, Dynamic Host Configuration Protocol
 RFC 2132, DHCP Options and BOOTP Vendor Extensions
The method by which IP addresses are assigned to a PDN context is configured on an APN-by-APN basis. Each APN
template dictates whether it will support static or dynamic addresses. Dynamically assigned IP addresses for subscriber
PDN contexts can be assigned through the use of DHCP.
The P-GW acts as a DHCP server toward the UE and a DHCP client toward the external DHCP server. The DHCP
server function and DHCP client function on the P-GW are completely independent of each other; one can exist without
the other.
The P-GW does not support DHCP-relay.
Important: Currently, the P-GW only supports DHCP with IPv4 addresses. IPv6 address support is planned at a
later date.
Deferred IPv4 Address Allocation
Apart from obtaining IP addresses during initial access signalling, a UE can indicate via PCO options that it prefers to
obtain IP address and related configuration via DHCP after default bearer has been established. This is also know as
Deferred Address Allocation.
IPv4 addresses are becoming an increasingly scarce resource. Since 4G networks like LTE are always on, scarce
resources such as IPv4 addresses cannot/should not be monopolized by UEs when they are in an ECM -IDLE state.
PDN-type IPv4v6 allows a dual stack implementing. The P-GW allocates an IPv6 address only by default for an IPv4v6
PDN type. The UE defers the allocation of IPv4 addresses based upon its needs, and relinquishes any IPv4 addresses to
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the global pool once it is done. The P-GW may employ any IPv4 address scheme (local pool or external DHCP server)
when providing an IPv4 address on demand.
DHCPv6 Support
The Dynamic Host Configuration Protocol (DHCP) for IPv6 enables the DHCP servers to pass the configuration
parameters, such as IPv6 network addresses to IPv6 nodes. It offers the capability of allocating the reusable network
addresses and additional configuration functionality automatically.
The DHCPv6 support does not just feature the address allocation, but also fulfills the requirements of Network Layer IP
parameters. Apart from these canonical usage modes, DHCPv6's Prefix-Delegation (DHCP-PD) has also been
standardized by 3GPP (Rel 10) for “network-behind-ue” scenarios. P-GW manages IPv6 prefix life-cycle just like it
manages IPv4 addresses, thus it is responsible for allocation, renew, and release of these prefixes during the lifetime of a
call. IPv6 prefixes may be obtained from either local-pool, AAA (RADIUS/DIAMETER) or external DHCPv6 servers.
Stateless DHCPv6 procedures are used to supply higher layer IP parameters to the end host.
DHCPv6 support for P-GW covers the following requirements:
 RFC 3633, prefix delegation and Stateless services (primarily via the INFORMATION-REQUEST) mechanism
 RFC 2132, DHCP Options and BOOTP Vendor Extensions
 RFC 4039, Rapid Commit Support
Important: For more information on DHCPv6 service configuration, refer to the DHCPv6 Configuration section
of the PDN Gateway Configuration chapter.
Direct Tunnel Support
When Gn/Gp interworking with pre-release SGSNs is enabled, the GGSN service on the P-GW supports direct tunnel
functionality.
Direct tunnel improves the user experience (e.g. expedited web page delivery, reduced round trip delay for
conversational services, etc.) by eliminating SGSN tunnel “switching” latency from the user plane. An additional
advantage of direct tunnel from an operational and capital expenditure perspective is that direct tunnel optimizes the
usage of user plane resources by removing the requirement for user plane processing on the SGSN.
The direct tunnel architecture allows the establishment of a direct user plane tunnel between the RAN and the GGSN,
bypassing the SGSN. The SGSN continues to handle the control plane signalling and typically makes the decision to
establish direct tunnel at PDP Context Activation. A direct tunnel is achieved at PDP context activation by the SGSN
establishing a user plane (GTP-U) tunnel directly between RNC and GGSN (using an Update PDP Context Request
toward the GGSN).
A major consequence of deploying direct tunnel is that it produces a significant increase in control plane load on both
the SGSN and GGSN components of the packet core. It is therefore of paramount importance to a wireless operator to
ensure that the deployed GGSNs are capable of handling the additional control plane loads introduced of part of direct
tunnel deployment. The Cisco GGSN and SGSN offer massive control plane transaction capabilities, ensuring system
control plane capacity will not be a capacity limiting factor once direct tunnel is deployed.
Important: For more information on direct tunnel support, refer to the Direct Tunnel appendix in this guide.
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DNS Support for IPv4/IPv6 PDP Contexts
This feature adds functionality in P-GW for PDN type IPv4v6. in StarOS Release 15.0. Previously, if an MS requested
an IPv4 DNS address, P-GW did not send the IPv4 DNS address.
MS may request for DNS server IPv4 or IPv6 addresses using the Protocol Configurations Options IE (as a container or
as part of IPCP protocol configuration request) in PDP Context Activation procedure for PDP Type IPv4, IPv6, or
IPv4v6. In that case, the P-GW may return the IP address of one or more DNS servers in the PCO IE in the PDP
Context Activation Response message. The DNS address(es) shall be coded in the PCO as specified in 3GPP TS 24.008.
For PDP Type IPv4v6, if MS requested DNS server IPv4 address, it did not return anIPv4 address. Support is now
added to respond with address requested by MS.
AAA server may also provide DNS Server IP Address in Access-Accept Auth Response. In such cases, AAA provided
DNS server IPs takes priority over the one configured under APN.
When DNS server address is requested in PCO configuration, the following preference would be followed:
1. DNS values received from RADIUS Server.
2. DNS values locally configured with APN.
3. DNS values configured at context level with ip name-servers CLI.
Domain Based Flow Definitions
This solution provides improved flexibility and granularity in obtaining geographically correct exact IP entries of the
servers by snooping DNS responses.
Currently, it is possible to configure L7 rules to filter based on domain (m.google.com). Sometimes multiple servers
may serve a domain, each with its own IP address. Using an IP-rule instead of an http rule will result in multiple IPrules; one IP-rule for each server “behind” the domain, and it might get cumbersome to maintain a list of IP addresses
for domain-based filters.
In this solution, you can create ruledefs specifying hostnames (domain names) and parts of hostnames (domain names).
Upon the definition of the hostnames/domain names or parts of them, the P-GW will monitor all the DNS responses sent
towards the UE and will snoop only the DNS response, which has q-name or a-name as specified in the rules, and
identify all the IP addresses resulted from the DNS responses. DNS snooping will be done on live traffic for every
subscriber.
DSCP Marking
Provides support for more granular configuration of DSCP marking.
For Interactive Traffic class, the P-GW supports per-gateway service and per-APN configurable DSCP marking for
Uplink and Downlink direction based on Allocation/Retention Priority in addition to the current priorities.
The following matrix may be used to determine the Diffserv markings used based on the configured traffic class and
Allocation/Retention Priority:
Table 1. Default DSCP Value Matrix
Allocation Priority
1
2
3
Traffic Handling Priority
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Allocation Priority
1
2
3
1
ef
ef
ef
2
af21
af21
af21
3
af21
af21
af21
In addition, the P-GW allows configuration of diameter packets with DSCP values.
GTP-U on per APN Basis
This feature provides the flexibility to have a different DSCP marking table on per APN basis so that traffic on each of
the APNs can be marked differently, depending on the needs of the APN.
The S-GW/P-GW supports configurable DSCP marking of the outer header of a GTP-U tunnel packet based on a
QCI/THP table for the S5/S8 and Gn/Gp interfaces. This feature allows configuring DSCP marking table on a per APN
basis.
Previously, DSCP marking table was configured on P-GW service level. As part of this requirement, CLI was added to
associate the qos-qci-mapping table in APN.
Important: The SAEGW does not support non-standard QCI values. QCI values 1 through 9 are standard values
and are defined in 3GPP TS 23.203; the SAEGW supports these standard values.
In order to be backward compatible with older configurations, if a DSCP marking table is associated with P-GW service
and not with the APN, then the one in P-GW service will be used. If table is associated in both P-GW service and APN,
then the one on APN will take precedence.
Dynamic GTP Echo Timer
The Dynamic GTP Echo Timer enables the eGTP and GTP-U services to better manage GTP paths during network
congestion. As opposed to the default echo timer, which uses fixed intervals and retransmission timers, the dynamic
echo timer adds a calculated round trip timer (RTT) that is generated once a full request/response procedure has
completed. A multiplier can be added to the calculation for additional support during congestion periods.
Important: For more information, refer to the Configuring the GTP Echo Timer section located in the
Configuring Optional Features on the P-GW section of the PDN Gateway Configuration chapter.
Dynamic Policy Charging Control (Gx Reference Interface)
Dynamic policy and charging control provides a primary building block toward the realization of IMS multimedia
applications. In contrast to statically provisioned architectures, the dynamic policy framework provides a centralized
service control layer with global awareness of all access-side network elements. The centralized policy decision
elements simplify the process of provisioning global policies to multiple access gateways. Dynamic policy is especially
useful in an Always-On deployment model as the usage paradigm transitions from a short lived to a lengthier online
session in which the volume of data consumed can be extensive. Under these conditions dynamic policy management
enables dynamic just in-time resource allocation to more efficiently protect the capacity and resources of the network.
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Dynamic Policy Control represents the ability to dynamically authorize and control services and application flows
between a Policy Charging Enforcement Function (PCEF) on the P-GW and the PCRF. Policy control enables a
centralized and decoupled service control architecture to regulate the way in which services are provisioned and
allocated at the bearer resource layer.
The StarOS 9.0 release included enhancements to conform with 3GPP TS 29.212 and 29.230 functions. The Gx
reference interface uses Diameter transport and IPv6 addressing. The subscriber is identified to the PCRF at session
establishment using IMSI based NAIs within the Subscription-ID AVP. Additionally the IMEI within the EquipmentInfo AVP is used to identify the subscriber access terminal to the policy server. The Gx reference interface supports the
following capabilities:
 Authorize the bearer establishment for a packet flow
 Dynamic L3/L4 transfer of service data flow filters within PCC rules for selection and policy enforcement of
downlink/uplink IP CAN bearers
 Support static pre-provisioned L7 rulebase name attribute as trigger for activating Inline Services such as Peerto-Peer Detection
 Authorize the modification of a service data flow
 Revoke the authorization of a packet flow
 Provision PCC rules for service data flows mapped to default or dedicated EPS bearers
 Support P-GW initiated event triggers based on change of access network gateway or IP CAN
 Provide the ability to set or modify APN-AMBR for a default EPS bearer
 Create or modify QoS service priority by including QCI values in PCC rules transmitted from PCRF to PCEF
functions
Enhanced Charging Service (ECS)
The Enhanced Charging Service provides an integrated in-line service for inspecting subscriber data packets and
generating detail records to enable billing based on usage and traffic patterns. Other features include:
 Content Analysis Support
 Content Service Steering
 Support for Multiple Detail Record Types
 Diameter Credit Control Application
 Accept TCP Connections from DCCA Server
 Gy Interface Support
The Enhanced Charging Service (ECS) is an in-line service feature that is integrated within the system. ECS enhances
the mobile carrier's ability to provide flexible, differentiated, and detailed billing to subscribers by using Layer 3
through Layer 7 deep packet inspection with the ability to integrate with back-end billing mediation systems.
ECS interacts with active mediation systems to provide full real-time prepaid and active charging capabilities. Here the
active mediation system provides the rating and charging function for different applications.
In addition, ECS also includes extensive record generation capabilities for post-paid charging with in-depth
understanding of the user session. Refer to the Support for Multiple Detail Record Types section for more information.
The major components include:
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 Service Steering: Directs subscriber traffic into the ECS subsystem. Service Steering is used to direct selective
subscriber traffic flows via an Access Control List (ACL). It is used for other redirection applications as well
for both internal and external services and servers.
 Protocol Analyzer: The software stack responsible for analyzing the individual protocol fields and states during
packet inspection. It performs two types of packet inspection:
 Shallow Packet Inspection: inspection of the layer 3 (IP header) and layer 4 (e.g. UDP or TCP header)
information.
 Deep Packet Inspection: inspection of layer 7 and 7+ information. Deep packet inspection
functionality includes:
 Detection of URI (Uniform Resource Identifier) information at level 7 (e.g., HTTP, WTP,
RTSP Uniform Resource Locators (URLs)).
 Identification of true destination in the case of terminating proxies, where shallow packet
inspection would only reveal the destination IP address / port number of a terminating proxy.
 De-encapsulation of upper layer protocol headers, such as MMS-over-WTP, WSP-over-UDP,
and IP-over GPRS.
 Verification that traffic actually conforms to the protocol the layer 4 port number suggests.
 Rule Definitions: User-defined expressions, based on protocol fields and/or protocol-states, which define what
actions to take when specific field values are true. Expressions may contain a number of operator types (string,
=, >, etc.) based on the data type of the operand. Each Ruledef configuration is consisting of multiple
expressions applicable to any of the fields or states supported by the respective analyzers.
 Rule Bases: a collection of rule definitions and their associated billing policy. The rule base determines the
action to be taken when a rule is matched. It is possible to define a rule definition with different actions.
Mediation and Charging Methods
To provide maximum flexibility when integrating with billing mediation systems, ECS supports a full range of charging
and authorization interfaces.
 Pre-paid: In a pre-paid environment, the subscribers pay for service prior to use. While the subscriber is using
the service, credit is deducted from subscriber's account until it is exhausted or call ends. The pre-paid
accounting server is responsible for authorizing network nodes (GGSNs) to grant access to the user, as well as
grant quotas for either time connected or volume used. It is up to the network node to track the quota use, and
when these use quotas run low, the network node sends a request to the pre-paid server for more quota.
If the user has not used up the purchased credit, the server grants quota and if no credit is available to the
subscriber the call will be disconnected. ECS and DCCA manage this functionality by providing the ability to
setup quotas for different services.
Pre-paid quota in ECS is implemented using DIAMETER Credit Control Application (DCCA). DCCA
supports the implementation of real-time credit control for a variety of services, such as networks access,
messaging services, and download services.
In addition to being a general solution for real-time cost and credit control, DCCA includes these features:
 Real-time Rate Service Information - DCCA can verify when end subscribers' accounts are exhausted
or expired; or deny additional chargeable events.
 Support for Multiple Services - DCCA supports the usage of multiple services within one subscriber
session. Multiple Service support includes; 1) ability to identify and process the service or g roup of
services that are subject to different cost structures 2) independent credit control of multiple services
in a single credit control sub-session.
Refer to the Diameter Credit Control Application section for more information.
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 Post-paid: In a post-paid environment, the subscribers pay after use of the service. A AAA server is responsible
for authorizing network nodes (GGSNs) to grant access to the user and a CDR system generates G-CDRs/eGCDRs/EDRs/UDRs or Comma Separated Values (CSVs) for billing information on pre-defined intervals of
volume or per time.
Important: Support for the Enhanced Charging Service requires a service license; the ECS license is included in
the P-GW session use license. For more information on ECS, refer to the Enhanced Charging Service Administration
Guide.
Content Analysis Support
The Enhanced Charging Service is capable of performing content analysis on packets of many different protocols at
different layers of the OSI model.
The ECS content analyzers are able to inspect and maintain state across various protocols at all layers of the OSI stack.
ECS system supports, inspects, and analyzes the following protocols:
 IP
 TCP
 UDP
 DNS
 FTP
 TFTP
 SMTP
 POP3
 HTTP
 ICMP
 WAP: WTP and WSP
 Real-Time Streaming: RTP and RTSP
 MMS
 SIP and SDP
 File analysis: examination of downloaded file characteristics (e.g. file size, chunks transferred, etc.) from file
transfer protocols such as HTTP and FTP.
Traffic analyzers in enhanced charging subsystem are based on configured rules. Rules used for Traffic analysis analyze
packet flows and form usage records. Usage records are created per content type and forwarded to a pre-paid server or
to a mediation/billing system. A traffic analyzer performs shallow (Layer 3 and Layer 4) and deep (above Layer 4)
packet inspection of the IP packet flows.
The Traffic Analyzer function is able to do a shallow (layer 3 and layer 4) and deep (above layer 4) packet inspection of
IP Packet Flows.
It is able to correlate all layer 3 packets (and bytes) with higher layer trigger criteria (e.g. URL detected in a HTTP
header) and it is also perform stateful packet inspection to complex protocols like FTP, RTSP, SIP that dynamically
open ports for the data path and by this way, user plane payload is differentiated into “categories”.
The Traffic Analyzer works on the application level as well and performs event based charging without the interference
of the service platforms.
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Important: This functionality is available for use with the Enhanced Charging Service which requires a sessionuse license. For more information on ECS, refer to the Enhanced Charging Service Administration Guide.
Content Service Steering
Content Service Steering (CSS) directs selective subscriber traffic into the ECS subsystem (In -line services internal to
the system) based on the content of the data presented by mobile subscribers.
CSS uses Access Control Lists (ACLs) to redirect selective subscriber traffic flows. ACLs control the flow of packets
into and out of the system. ACLs consist of “rules” (ACL rules) or filters that control the action taken on packets
matching the filter criteria.
ACLs are configurable on a per-context basis and applies to a subscriber through either a subscriber profile or an APN
profile in the destination context.
Important: For more information on CSS, refer to the Content Service Steering chapter of the System
Administration Guide.
Important: For more information on ACLs, refer to the IP Access Control Lists chapter of the System
Administration Guide.
Support for Multiple Detail Record Types
To meet the requirements of standard solutions and at the same time, provide flexible and detailed information on
service usage, the Enhanced Charging Service (ECS) provides the following type of usage records:
 Event Detail Records (EDRs)
 Usage Detail Records (UDRs)
ECS provides for the generation of charging data files, which can be periodically retrieved from the system and used as
input to a billing mediation system for post-processing. These files are provided in a standard format, so that the impact
on the existing billing/mediation system is minimal and at the same time, these records contain all the information
required for billing based on the content.
GTPP accounting in ECS allows the collection of counters for different types of data traffic into detail records. The
following types of detail records are supported:
 Event Detail Records (EDRs): An alternative to standard G-CDRs when the information provided by the GCDRs is not sufficient to do the content billing. EDRs are generated according to explicit action statements in
rule commands that are user-configurable. The EDRs are generated in comma separated values (CSV) format,
generated as defined in traffic analysis rules.
 User Detail Records (UDRs): Contain accounting information related to a specific mobile subscriber. The fields
to be reported in them are user-configurable and are generated on any trigger of time threshold, volume
threshold, handoffs, and call termination. The UDRs are generated in comma separated values (CSV) format,
generated as defined in traffic analysis rules.
Important: This functionality is available for use with the Enhanced Charging Service which requires a sessionuse license. For more information on ECS, refer to the Enhanced Charging Service Administration Guide.
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Diameter Credit Control Application
Provides a pre-paid billing mechanism for real-time cost and credit control based on the following standards:
 RFC 3588, Diameter Base Protocol, September 2003
 RFC 4006, Diameter Credit-Control Application, August 2005
The Diameter Credit Control Application (DCCA) is used to implement real-time credit-control for a variety of end user
services such as network access, Session Initiation Protocol (SIP) services, messaging services, download services etc.
Used in conjunction with ECS, the DCCA interface uses a mechanism to allow the user to be informed of the charges to
be levied for a requested service. In addition, there are services such as gaming and advertising that may credit as well
as debit from a user account.
DCCA also supports the following:
 Real-time Rate Service Information: The ability to verify when end subscribers' accounts are exhausted or
expired; or deny additional chargeable events.
 Support for Multiple Services: The usage of multiple services within one subscriber session is supported.
Multiple Service support includes:
 The ability to identify and process the service or group of services that are subject to different cost
structures.
 Independent credit control of multiple services in a single credit control sub-session.
Important: This functionality is available for use with the Enhanced Charging Service, which requires a sessionuse license. For more information on ECS, refer to the Enhanced Charging Service Administration Guide.
Accept TCP Connections from DCCA Server
This feature allows for peer Diameter Credit Control Application servers to initiate a connection the NGME.
This feature allows peer diameter nodes to connect to the NGME on TCP port 3868 when the diameter server is
incapable of receiving diameter incoming diameter requests.
Important: For more information on Diameter support, if you are using StarOS 12.3 or an earlier release, refer to
the AAA and GTPP Interface Administration and Reference. If you are using StarOS 14.0 or a later release, refer to the
AAA Interface Administration and Reference.
Gy Interface Support
The Gy interface enables the wireless operator to implement a standardized interface for real time content based
charging with differentiated rates for time based and volume based charging.
As it is based on a quota mechanism, the Gy interface enables the wireless operator to spare expensive Prepaid System
resources.
As it enables time-, volume-, and event-based charging models, the Gy interface flexibly enables the operator to
implement charging models tailored to their service strategies.
The Gy interface provides a standardized Diameter interface for real time content based charging of data services. It is
based on the 3GPP standards and relies on quota allocation.
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It provides an online charging interface that works with the ECS deep packet inspection feature. With Gy, customer
traffic can be gated and billed in an “online” or “prepaid” style. Both time- and volume-based charging models are
supported. In all of these models, differentiated rates can be applied to different services based on shallow or deep
packet inspection.
Gy is a Diameter interface. As such, it is implemented atop, and inherits features from, the Diameter Base Protocol. The
system supports the applicable Base network and application features, including directly connected, relayed or proxied
DCCA servers using TLS or plaintext TCP.
In the simplest possible installation, the system exchanges Gy Diameter messages over Diameter TCP links between
itself and one “prepay” server. For a more robust installation, multiple servers would be used. These servers may
optionally share or mirror a single quota database so as to support Gy session failover from one server to the other. For a
more scalable installation, a layer of proxies or other Diameter agents can be introduced to provide features such as
multi-path message routing or message and session redirection features.
The Cisco implementation is based on the following standards:
 RFC 4006 generic DCCA, including:
 CCR Initial, Update, and Final signaling
 ASR and RAR asynchronous DCCA server messages
 Time, Total-Octets, and Service-Specific-Units quota management
 Multiple independent quotas using Multiple-Services-Credit-Control
 Rating-Group for quota-to-traffic association
 CC-Failure-Handling and CC-Session-Failover features
 Final-Unit-Action TERMINATE behavior
 Tariff-Time-Change feature.
 3GPP TS 32.299 online mode “Gy” DCCA, including:
 Final-Unit-Action REDIRECT behavior
 Quota-Holding-Time: This defines a user traffic idle time, on a per category basis, after which the usage
is returned and no new quota is explicitly requested
 Quota-Thresholds: These AVPs define a low value watermark at which new quota will be sought before
the quota is entirely gone; the intent is to limit interruption of user traffic.
These AVPs exist for all quota flavors, for example “Time-Quota-Threshold”.
 Trigger-Type: This AVP defines a set of events which will induce a re-authentication of the current
session and its quota categories.
Gn/Gp Handoff Support
In LTE deployments, smooth handover support is required between 3G/2G and LTE networks, and Evolved Packet
Core (EPC) is designed to be a common packet core for different access technologies. P-GW supports handovers as user
equipment (UE) moves across different access technologies.
Cisco's P-GW supports inter-technology mobility handover between 4G and 3G/2G access. Interworking is supported
between the 4G and 2G/3G SGSNs, which provide only Gn and Gp interfaces but no S3, S4 or S5/S8 interfaces. These
Gn/Gp SGSNs provide no functionality introduced specifically for the evolved packet system (EPS) or for
interoperation with the E-UTRAN. These handovers are supported only with a GTP-based S5/S8 and P-GW supports
handoffs between GTPv2 based S5/S8 and GTPv1 based Gn/Gp tunneled connections. In this scenario, the P-GW works
as an IP anchor for the EPC.
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Important: To support the seamless handover of a session between GGSN and P-GW, the two independent
services must be co-located on the same node and configured within the same context for optimum interoperation.
Important: For more information on Gn/GP handoffs, refer to Gn/Gp GGSN/SGSN (GERAN/UTRAN) in the
Supported Logical Network Interfaces (Reference Points) section in this chapter.
IMS Emergency Bearer Handling
With this support, a UE is able to connect to an emergency PDN and make Enhanced 911 (E911) calls while providing
the required location information to the Public Safety Access Point (PSAP).
E911 is a telecommunications-based system that is designed to link people who are experiencing an emergency with the
public resources that can help. This feature supports E911-based calls across the LTE and IMS networks. In a voice over
LTE scenario, the subscriber attaches to a dedicated packet data network (PDN) called EPDN (Emergency PDN) in
order to establish a voice over IP connection to the PSAP. Signaling either happens on the default emergency bearer, or
signaling and RTP media flow over separate dedicated emergency bearers. Additionally, different than normal PDN
attachment that relies on AAA and PCRF components for call establishment, the EPDN attributes are configured locally
on the P-GW, which eliminates the potential for emergency call failure if either of these systems is not available.
Emergency bearer services are provided to support IMS emergency sessions. Emergency bearer services are
functionalities provided by the serving network when the network is configured to support emergency services.
Emergency bearer services are provided to normally attached UEs and to UEs that are in a limited service state
(depending on local service regulations, policies, and restrictions). Receiving emergency services in limited service state
does not require a subscription.
The standard (refer to 3GPP TS 23.401) has identified four behaviors that are supported:
 Valid UEs only
 Authenticated UEs only
 MSI required, authentication optional
 All UEs
To request emergency services, the UE has the following two options:
 UEs that are in a limited service state (due to attach reject from the network, or since no SIM is present), initiate
an ATTACH indicating that the ATTACH is for receiving emergency bearer services. After a successful
attach, the services that the network provides the UE is solely in the context of Emergency Bearer Services.
 UEs that camp normally on a cell initiates a normal ATTACH if it requires emergency services. Normal attached
UEs initiated a UE Requested PDN Connectivity procedure to request Emergency Bearer Services.
IP Access Control Lists
IP access control lists allow you to set up rules that control the flow of packets into and out of the system ba sed on a
variety of IP packet parameters.
IP access lists, or access control lists (ACLs) as they are commonly referred to, are used to control the flow of packets
into and out of the system. They are configured on a per-context basis and consist of “rules” (ACL rules) or filters that
control the action taken on packets that match the filter criteria. Once configured, an ACL can be applied to any of the
following:
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 An individual interface
 All traffic facilitated by a context (known as a policy ACL)
 An individual subscriber
 All subscriber sessions facilitated by a specific context
Important: For more information on IP access control lists, refer to the IP Access Control Lists chapter in the
System Administration Guide.
IP Address Hold Timers
Also known as address quarantining, this subscriber-level CLI introduces an address hold timer to temporarily buffer a
previously assigned IP address from an IP address pool to prevent it from being recycled and reassigned to a new
subscriber session. It is especially useful during inter-RAT handovers that sometimes lead to temporary loss of the
mobile data session.
This feature provides a higher quality user experience for location-based services where the remote host server needs to
reach the mobile device.
Important: Currently, the P-GW only supports an address hold timer with IPv4 addresses.
IPv6 Capabilities
Enables increased address efficiency and relieves pressures caused by rapidly approaching IPv4 address exhaustion
problem.
The P-GW offers the following IPv6 capabilities:
Native IPv6 and IPv6 transport
 Support for any combination of IPv4, IPv6 or dual stack IPv4/v6 address assignment from dynamic or static
address pools on the P-GW.
 Support for native IPv6 transport and service addresses on PMIPv6 S2a interface. Note that transport on GTP
S5/S8 connections in this release is IPv4 based.
 Support for IPv6 transport for outbound traffic over the SGi reference interface to external Packet Data
Networks.
IPv6 Connections to Attached Elements
IPv6 transport and interfaces are supported on all of the following connections:
 Diameter Gx policy signaling interface
 Diameter Gy online charging reference interface
 S6b authentication interface to external 3GPP AAA server
 Diameter Rf offline charging interface
 Lawful Intercept (X1, X2 interfaces)
Routing and Miscellaneous Features
 OSPFv3
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 MP-BGP v6 extensions
 IPv6 flows (Supported on all Diameter QoS and Charging interfaces as well as Inline Services (e.g. ECS)
Local Break-Out
Provides a standards-based procedure to enable LTE operators to generate additional revenues by accepting traffic from
visited subscribers based on roaming agreements with other mobile operators.
Local Breakout is a policy-based forwarding function that plays an important role in inter-provider roaming between
LTE service provider networks. Local Breakout is determined by the SLAs for handling roaming calls between visited
and home networks. In some cases, it is more beneficial to locally breakout a roaming call on a foreign network to the
visited P-W rather than incur the additional transport costs to backhaul the traffic to the Home network.
If two mobile operators have a roaming agreement in place, Local Break-Out enables the visited user to attach to the VPLMN network and be anchored by the local P-GW in the visited network. The roaming architecture relies on the HSS
in the home network and also introduces the concept of the S9 policy signaling interface between the H-PCRF in the HPLMN and the V-PCRF in the V-PLMN. When the user attaches to the EUTRAN cell and MME (Mobility
Management Entity) in the visited network, the requested APN name in the S6a NAS signaling is used by the HSS in
the H-PLMN to select the local S-GW (Serving Gateway) and P-GWs in the visited EPC network.
Management System Overview
The system's management capabilities are designed around the Telecommunications Management Network (TMN)
model for management - focusing on providing superior quality network element (NE) and element management system
(Cisco Web Element Manager) functions. The system provides element management applications that can easily be
integrated, using standards-based protocols (CORBA and SNMPv1, v2), into higher-level management systems - giving
wireless operators the ability to integrate the system into their overall network, service, and business management
systems. In addition, all management is performed out-of-band for security and to maintain system performance.
Cisco's O&M module offers comprehensive management capabilities to the operators and enables them to operate the
system more efficiently. There are multiple ways to manage the system either locally or remotely using its out -of-band
management interfaces.
These include:
 Using the command line interface (CLI)
 Remote login using Telnet, and Secure Shell (SSH) access to CLI through SPIO card's Ethernet management
interfaces
 Local login through the Console port on SPIO card using an RS-232 serial connection
 Using the Web Element Manager application
 Supports communications through 10 Base-T, 100 Base-TX, 1000 Base-TX, or 1000
 Base-SX (optical gigabit Ethernet) Ethernet management interfaces on the SPIO
 Client-Server model supports any browser (i.e. Microsoft Internet Explorer v5.0 and above or Netscape v4.7 or
above, and others)
 Supports Common Object Request Broker Architecture (CORBA) protocol and Simple Network Management
Protocol version 1 (SNMPv1) for fault management
 Provides complete Fault, Configuration, Accounting, Performance, and Security (FCAPS) capabilities
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 Can be easily integrated with higher-level network, service, and business layer applications using the Object
Management Group's (OMG’s) Interface Definition Language (IDL)
The following figure demonstrates these various element management options and how they can be utilized within the
wireless carrier network.
Figure 13.
Element Management Methods
Important: P-GW management functionality is enabled by default for console-based access. For GUI-based
management support, refer to the Web Element Management System section in this chapter.
Important: For more information on command line interface based management, refer to the Command Line
Interface Reference.
MPLS EXP Marking of User Plane Traffic
Similar to 802.1p marking, MPLS EXP bit marking is supported for Enterprise APN’s that use MPLS tunneling on the
SGi interface on the P-GW. The QoS marking used in the LTE/EPC network (QCI per EPS bearer) is mapped to the
802.1p and MPLS EXP bit marking between the P-GW and L2/EPC switch and MPLS/PE routers (this is applicable to
the upstream direction, from the P-GW to the Network).MPLS EXP marking related configuration is available as part of
the QCI-QOS configuration table. MPLS EXP marking is selected based on QCI of the bearer to which that packet
belongs.
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Important: The SAEGW does not support non-standard QCI values. QCI values 1 through 9 are
standard values and are defined in 3GPP TS 23.203; the SAEGW supports these standard values.
Mobile IP Registration Revocation
Mobile IP registration revocation functionality provides the following benefits:
 Timely release of Mobile IP resources at the HSGW and/or P-GW
 Accurate accounting
 Timely notification to mobile node of change in service
Registration Revocation is a general mechanism whereby either the P-GW or the HSGW providing Mobile IP
functionality to the same mobile node can notify the other mobility agent of the termination of a binding. Mobile IP
Registration Revocation can be triggered at the HSGW by any of the following:
 Session terminated with mobile node for whatever reason
 Session renegotiation
 Administrative clearing of calls
 Session Manager software task outage resulting in the loss of HSGW sessions (sessions that could not be
recovered)
Important: Registration Revocation functionality is also supported for Proxy Mobile IP. However, only the PGW can initiate the revocation for Proxy-MIP calls.
Important: For more information on MIP registration revocation support, refer to the Mobile IP Registration
Revocation appendix in this guide.
MTU Size PCO
UEs usually use a hardcoded MTU size for IP communication. If this hardcoded value is not in sync with the network
supported value, it can lead to unnecessary fragmentation of packets sent by the UE. Thus, in order to avoid unnecessary
fragmentation, this feature helps in using the network-provided MTU size instead of the hardcoded MTU in UE.
3GPP defined a new PCO option in Release 10 specifications for the network to be able to provide an IPv4 MTU size to
the UE. P-GW supports an option to configure a IPv4 Link MTU size in the APN profile.
If the UE requests IPv4 Link MTU size in the PCO options during Initial Attach or PDN connectivity request, the P-GW
will provide the preconfigured value based on the APN.
If the MTU size configuration on APN is changed, the new MTU size will take effect only for new PDN connections
and initial attaches. P-GW will not update for the existing PDN connections.
If UE does not request IPv4 Link MTU size, P-GW will not include the IPv4 Link MTU size.
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Multiple PDN Support
Enables an APN-based user experience that enables separate connections to be allocated for different services including
IMS, Internet, walled garden services, or off-deck content services.
The MAG function on the S-GW can maintain multiple PDN or APN connections for the same user session. The MAG
runs a single node level Proxy Mobile IPv6 tunnel for all user sessions toward the LMA function of the P-GW. When a
user wants to establish multiple PDN connections, the MAG brings up the multiple PDN connections over the same
PMIPv6 session to one or more P-GW LMA's. The P-GW in turn allocates separate IP addresses (Home Network
Prefixes) for each PDN connection and each one can run one or multiple EPC default & dedicated bearers. To request
the various PDN connections, the MAG includes a common MN-ID and separate Home Network Prefixes, APNs and a
Handover Indication Value equal to one in the PMIPv6 Binding Updates.
Important: Up to 11 multiple PDN connections are supported.
Node Functionality GTP Echo
This feature helps exchange capabilities of two communicating GTP nodes, and uses the new feature based on whether
it is supported by the other node.
This feature allows S-GW to exchange its capabilities (MABR, PRN, NTSR) with the peer entities through ECHO
messages. By this, if both the peer nodes support some common features, then they can make use of new messages to
communicate with each other.
With new “node features” IE support in ECHO request/response message, each node can send its supported features
(MABR, PRN, NTSR). This way, S-GW can learn the peer node’s supported features. S-GW’s supported features can
be configured by having some configuration at the service level.
If S-GW wants to use new message, such as P-GW Restart Notification, then S-GW should check if the peer node
supports this new feature or not. If the peer does not support it, then S-GW should fall back to old behavior.
If S-GW receives a new message from the peer node, and if S-GW does not support this new message, then S-GW
should ignore it. If S-GW supports the particular feature, then it should handle the new message as per the specification.
Non-Optimized e-HRPD to Native LTE (E-UTRAN) Mobility Handover
This feature enables a seamless inter-technology roaming capability in support of dual mode e-HRPD/e-UTRAN access
terminals.
The non-optimized inter-technology mobility procedure is rooted at the P-GW as the mobility anchor point for
supporting handovers for dual radio technology e-HRPD/E-UTRAN access terminals. To support this type of call
handover, the P-GW supports handoffs between the GTP-based S5/S8 (GTPv2-C / GTPv1-U) and PMIPv6 S2a
tunneled connections. It also provisions IPv4, IPv6, or dual stack IPv4/IPv6 PDN connections from a common address
pool and preserves IP addresses assigned to the UE during inter-technology handover. In the current release, the native
LTE (GTP-based) P-GW service address is IPv4-based, while the e-HRPD (PMIP) address is an IPv6 service address.
During the initial network attachment for each APN that the UE connects to, the HSS returns the FQDN of the P-GW
for the APN. The MME uses DNS to resolve the P-GW address. When the PDN connection is established in the P-GW,
the P-GW updates the HSS with the IP address of the P-GW on PDN establishment through the S6b authentication
process. When the mobile user roams to the e-HRPD network, the HSS returns the IP address of the P-GW in the P-GW
Identifier through the STa interface and the call ends up in the same P-GW. The P-GW is also responsible for initiating
the session termination on the serving access connection after the call handover to the target network.
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During the handover procedure, all dedicated EPS bearers must be re-established. On LTE- handovers to a target eHRPD access network, the dedicated bearers are initiated by the mobile access terminal. In contrast, on handovers in the
opposite direction from e-HRPD to LTE access networks, the dedicated bearers are network initiated through Gx policy
interactions with the PCRF server.
Finally, in order to support the inter-technology handovers, the P-GW uses common interfaces and Diameter endpoint
addresses for the various reference points:
 S6b: Non-3GPP authentication
 Gx: QoS Policy and Charging
 Rf: Offline Charging
All three types of sessions are maintained during call handovers. The bearer binding will be performed by the HSGW
during e-HRPD access and by the P-GW during LTE access. Thus, the Bearer Binding Event Reporting (BBERF)
function needs to migrate between the P-GW and the HSGW during the handover. The HSGW establishes a Gxa session
during e-HRPD access for bearer binding and releases the session during LTE access. The HSGW also maintains a
limited context during the e-HRPD <->LTE handover to reduce latency in the event of a quick handover from the LTE
RAN back to the e-HRPD network.
Important: For more information on handoff interfaces, refer to the Supported Logical Network Interfaces
(Reference Points) section in this chapter.
Online/Offline Charging
The Cisco EPC platform offers support for online and offline charging interactions with external OCS and CGF/CDF
servers.
Online Charging
Gy/Ro Reference Interfaces
The StarOS 9.0 online prepaid reference interface provides compatibility with the 3GPP TS 23.203, TS 32.240, TS
32.251 and TS 32.299 specifications. The Gy/Ro reference interface uses Diameter transport and IPv6 addressing.
Online charging is a process whereby charging information for network resource usage must be obtained by the network
in order for resource usage to occur. This authorization is granted by the Online Charging System (OCS) upon request
from the network. The P-GW uses a charging characteristics profile to determine whether to activate or deactivate
online charging. Establishment, modification or termination of EPS bearers is generally used as the event trigger on the
PCRF to activate online charging PCC rules on the P-GW.
When receiving a network resource usage request, the network assembles the relevant charging information and
generates a charging event towards the OCS in real-time. The OCS then returns an appropriate resource usage
authorization that may be limited in its scope (e.g. volume of data or duration based). The OCS assigns quotas for rat ing
groups and instructs the P-GW whether to continue or terminate service data flows or IP CAN bearers.
The following Online Charging models and functions are supported:
 Time based charging
 Volume based charging
 Volume and time based charging
 Final Unit Indication and termination or redirection of service data flows when quota is consumed
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 Reauthorization triggers to rearm quotas for one or more rating groups using multi-service credit control
(MSCC) instances
 Event based charging
 Billing cycle bandwidth rate limiting: Charging policy is enforced through interactions between the PDN GW
and Online Charging Server. The charging enforcement point periodically conveys accounting information for
subscriber sessions to the OCS and it is debited against the threshold that is established for the charging policy.
Subscribers can be assigned a max usage for their tier (gold, silver, bronze for example), the usage can be
tracked over a month, week, day, or peak time within a day. When the subscriber exceeds the usage li mit,
bandwidth is either restricted for a specific time period, or dropped depending on their tier of service.
 Fair usage controls
Offline Charging
Ga/Gz Reference Interfaces
The Cisco P-GW supports 3GPP-compliant offline charging as defined in TS 32.251,TS 32.297 and 32.298. Whereas
the S-GW generates SGW-CDRs to record subscriber level access to PLMN resources, the P-GW creates PGW-CDRs
to record user access to external networks. Additionally, when Gn/Gp interworking with pre-release SGSNs is enabled,
the GGSN service on the P-GW records G-CDRs to record user access to external networks.
To provide subscriber level accounting, the Cisco S-GW and P-GWs support integrated Charging Transfer Functions
(CTF) and Charging Data Functions (CDF). Each gateway uses Charging-ID's to distinguish between default and
dedicated bearers within subscriber sessions. The Ga/Gz reference interface between the CDF and CGF is used to
transfer charging records via the GTPP protocol. In a standards based implementation, the CGF consolidates the
charging records and transfers them via an FTP/S-FTP connection over the Bm reference interface to a back-end billing
mediation server. The Cisco EPC gateways also offer the ability to FTP/S-FTP charging records between the CDF and
CGF server. CDR records include information such as Record Type, Served IMSI, ChargingID, APN Name,
TimeStamp, Call Duration, Served MSISDN, PLMN-ID, etc. The ASR 5x00 platform offers a local directory to enable
temporary file storage and buffer charging records in persistent memory located on a pair of dual redundant RAID hard
disks. Each drive includes 147GB of storage and up to 100GB of capacity is dedicated to storing charging records. For
increased efficiency it also possible to enable file compression using protocols such as GZIP. The Offline Charging
implementation offers built-in heart beat monitoring of adjacent CGFs. If the Cisco P-GW has not heard from the
neighbor CGF within the configurable polling interval, they will automatically buffer the charging records on the local
drives until the CGF reactivates itself and is able to begin pulling the cached charging records.
The P-GW supports a Policy Charging Enforcement Function (PCEF) to enable Flow Based Bearer Charging (FBC) via
the Gy reference interface to adjunct OCS servers (See Online Charging description above).
Rf Reference Interface
The Cisco EPC platforms also support the Rf reference interface to enable direct transfer of charging files from the CTF
function of the P-GW to external CDF/CGF servers. This interface uses Diameter Accounting Requests (Start, Stop,
Interim, and Event) to transfer charging records to the CDF/CGF. Each gateway relies on triggering condit ions for
reporting chargeable events to the CDF/CGF. Typically as EPS bearers are activated, modified or deleted, charging
records are generated. The EPC platforms include information such as Subscription -ID (IMSI), Charging-ID (EPS
bearer identifier) and separate volume counts for the uplink and downlink traffic.
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Peer GTP Node Profile Configuration Support
Provides flexibility to the operators to have different configuration for GTP-C and Lawful Intercept, based on the type
of peer or the IP address of the peer
Peer profile feature allows flexible profile based configuration to accommodate growing requirements of customizable
parameters with default values and actions for peer nodes of P-GW. With this feature, configuration of GTP-C
parameters and disabling/enabling of Lawful Intercept per MCC/MNC or IP address based on rules defined.
A new framework of peer-profile and peer-map is introduced. Peer-profile configuration captures the GTP-C specific
configuration and/or Lawful Intercept enable/disable configuration. GTP-C configuration covers GTP-C retransmission
(maximum number of retries and retransmission timeout) and GTP echo configuration. Peer-map configuration matches
the peer-profile to be applied to a particular criteria. Peer-map supports criteria like MCC/MNC (PLMN-ID) of the peer
or IP-address of the peer. Peer-map can then be associated with P-GW service.
Intent of this feature is to provide flexibility to operators to configure a profile which can be applied to a specific set o f
peers. For example, have a different retransmission timeout for foreign peers as compared to home peers.
PMIPv6 Heartbeat
Proxy Mobile IPv6 (PMIPv6) is a network-based mobility management protocol to provide mobility without requiring
the participation of the mobile node in any PMIPv6 mobility related signaling. The core functional entities Mobile
Access Gateway (MAG) and the Local Mobility Anchor (LMA) set up tunnels dynamically to manage mobility for a
mobile node.
Path management mechanism through Heartbeat messages between the MAG and LMA is important to know the
reachability of the peers, to detect failures, quickly inform peers in the event of a recovery from node failures, and allow
a peer to take appropriate action.
PMIP heartbeats from the HSGW to the P-GW are supported per RFC 5847. Refer to the heartbeat command in the
LMA Service mode or MAG Service mode respectively to enable this heartbeat and configure the heartbeat variables.
Proxy Mobile IPv6 (S2a)
Provides a mobility management protocol to enable a single LTE-EPC core network to provide the call anchor point for
user sessions as the subscriber roams between native EUTRAN and non-native e-HRPD access networks
S2a represents the trusted non-3GPP interface between the LTE-EPC core network and the evolved HRPD network
anchored on the HSGW. In the e-HRPD network, network-based mobility provides mobility for IPv6 nodes without
host involvement. Proxy Mobile IPv6 extends Mobile IPv6 signaling messages and reuses the HA function (now known
as LMA) on the P-GW. This approach does not require the mobile node to be involved in the exchange of signaling
messages between itself and the Home Agent. A proxy mobility agent (e.g. MAG function on HSGW) in the network
performs the signaling with the home agent and does the mobility management on behalf of the mobile node attached to
the network.
The S2a interface uses IPv6 for both control and data. During the PDN connection establishment procedures the P-GW
allocates the IPv6 Home Network Prefix (HNP) via Proxy Mobile IPv6 signaling to the HSGW. The HSGW returns the
HNP in router advertisement or based on a router solicitation request from the UE. PDN connection release events can
be triggered by either the UE, the HSGW or the P-GW.
In Proxy Mobile IPv6 applications the HSGW (MAG function) and P-GW (LMA function) maintain a single shared
tunnel and separate GRE keys are allocated in the PMIP Binding Update and Acknowledgement messages to distinguish
between individual subscriber sessions. If the Proxy Mobile IP signaling contains Protocol Configuration Options
(PCOs) it can also be used to transfer P-CSCF or DNS server addresses
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QoS Bearer Management
Provides a foundation for contributing towards improved Quality of User Experience (QoE) by enabling deterministic
end-to-end forwarding and scheduling treatments for different services or classes of applications pursuant to their
requirements for committed bandwidth resources, jitter and delay. In this way, each application receives the service
treatment that users expect.
An EPS bearer is a logical aggregate of one or more Service Data Flows (SDFs), running between a UE and a P-GW in
case of GTP-based S5/S8, and between a UE and HSGW in case of PMIP-based S2a connection. An EPS bearer is the
level of granularity for bearer level QoS control in the EPC/E-UTRAN. The Cisco P-GW maintains one or more Traffic
Flow Templates (TFT's) in the downlink direction for mapping inbound Service Data Flows (SDFs) to EPS bearers. The
P-GW maps the traffic based on the downlink TFT to the S5/S8 bearer. The Cisco PDN GW offers all of the following
bearer-level aggregate constructs:
QoS Class Identifier (QCI): An operator provisioned value that controls bearer level packet forwarding treatments
(e.g. scheduling weights, admission thresholds, queue management thresholds, link layer protocol configuration, etc).
The Cisco EPC gateways also support the ability to map the QCI values to DiffServ code points in the outer GTP tunnel
header of the S5/S8 connection. Additionally, the platform also provides configurable parameters to copy the DSCP
marking from the encapsulated payload to the outer GTP tunnel header.
Important: The SAEGW does not support non-standard QCI values. QCI values 1 through 9 are standard values
and are defined in 3GPP TS 23.203; the SAEGW supports these standard values.
Guaranteed Bit Rate (GBR): A GBR bearer is associated with a dedicated EPS bearer and provides a guaranteed
minimum transmission rate in order to offer constant bit rate services for applications such as interactive voice that
require deterministic low delay service treatment.
Maximum Bit Rate (MBR): The MBR attribute provides a configurable burst rate that limits the bit rate that can be
expected to be provided by a GBR bearer (e.g. excess traffic may get discarded by a rate shaping function). The MBR
may be greater than or equal to the GBR for a given Dedicated EPS bearer.
Aggregate Maximum Bit Rate (AMBR): AMBR denotes a bit rate of traffic for a group of bearers destined for a
particular PDN. The Aggregate Maximum Bit Rate is typically assigned to a group of Best Effort service da ta flows
over the Default EPS bearer. That is, each of those EPS bearers could potentially utilize the entire AMBR, e.g. when the
other EPS bearers do not carry any traffic. The AMBR limits the aggregate bit rate that can be expected to be provided
by the EPS bearers sharing the AMBR (e.g. excess traffic may get discarded by a rate shaping function). AMBR applies
to all Non-GBR bearers belonging to the same PDN connection. GBR bearers are outside the scope of AMBR.
Policing: The Cisco P-GW offers a variety of traffic conditioning and bandwidth management capabilities. These tools
enable usage controls to be applied on a per-subscriber, per-EPS bearer or per-PDN/APN basis. It is also possible to
apply bandwidth controls on a per-APN AMBR capacity. These applications provide the ability to inspect and maintain
state for user sessions or Service Data Flows (SDFs) within them using shallow L3/L4 analysis or high touch deep
packet inspection at L7. Metering of out-of-profile flows or sessions can result in packet discards or reducing the DSCP
marking to Best Effort priority.
RADIUS Support
Provides a mechanism for performing authorization, authentication, and accounting (AAA) for subscri ber PDP contexts
based on the following standards:
 RFC-2618, RADIUS Authentication Client MIB, June 1999
 RFC-2620, RADIUS Accounting Client MIB, June 1999
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 RFC-2865, Remote Authentication Dial In User Service (RADIUS), June 2000
 RFC-2866, RADIUS Accounting, June 2000
 RFC-2867, RADIUS Accounting Modifications for Tunnel Protocol Support, June 2000
 RFC-2868, RADIUS Attributes for Tunnel Protocol Support, June 2000
 RFC-2869, RADIUS Extensions, June 2000
The Remote Authentication Dial-In User Service (RADIUS) protocol is used to provide AAA functionality for
subscriber PDP contexts. (RADIUS accounting is optional since GTPP can also be used.)
Within contexts configured on the system, there are AAA and RADIUS protocol-specific parameters that can be
configured. The RADIUS protocol-specific parameters are further differentiated between RADIUS Authentication
server RADIUS Accounting server interaction.
Among the RADIUS parameters that can be configured are:
 Priority: Dictates the order in which the servers are used allowing for multiple servers to be configured in a
single context.
 Routing Algorithm: Dictate the method for selecting among configured servers. The specified algorithm
dictates how the system distributes AAA messages across the configured AAA servers for new sessions. Once
a session is established and an AAA server has been selected, all subsequent AAA messages for the session
will be delivered to the same server.
In the event that a single server becomes unreachable, the system attempts to communicate wit h the other servers that
are configured. The system also provides configurable parameters that specify how it should behave should all of the
RADIUS AAA servers become unreachable.
The system provides an additional level of flexibility by supporting the configuration RADIUS server groups. This
functionality allows operators to differentiate AAA services for subscribers based on the APN used to facilitate their
PDP context.
In general, 128 AAA Server IP address/port per context can be configured on the system and it selects servers from this
list depending on the server selection algorithm (round robin, first server). Instead of having a single list of servers per
context, this feature provides the ability to configure multiple server groups. Each server group, in turn, consists of a list
of servers.
This feature works in following way:
 All RADIUS authentication/accounting servers configured at the context-level are treated as part of a server
group named “default”. This default server group is available to all subscribers in that context through the
realm (domain) without any configuration.
 It provides a facility to create “user defined” RADIUS server groups, as many as 399 (excluding “default” server
group), within a context. Any of the user defined RADIUS server groups are available for assignment to a
subscriber through the APN configuration within that context.
Since the configuration of the APN can specify the RADIUS server group to use as well as IP address pools from which
to assign addresses, the system implements a mechanism to support some in-band RADIUS server implementations (i.e.
RADIUS servers which are located in the corporate network, and not in the operator's network) where the NAS-IP
address is part of the subscriber pool. In these scenarios, the P-GW supports the configuration of the first IP address of
the subscriber pool for use as the RADIUS NAS-IP address.
Important: For more information on RADIUS AAA configuration, if you are using StarOS 12.3 or an earlier
release, refer to the AAA and GTPP Interface Administration and Reference. If you are using StarOS 14.0 or a later
release, refer to the AAA Interface Administration and Reference.
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S-GW Restoration Support
S-GW Restoration helps in handling the S-GW failure in the EPC network in a graceful manner. It allows affected
PDNs due to S-GW failure to be restored by selecting another S-GW to serve the affected PDNs, thus avoiding
unnecessary flooding of signaling for PDN cleanup.
S-GW Restoration is based on 3GPP Release 11. It requires enhancements at P-GW for maintaining the sessions in case
path failure is detected or when S-GW restart is detected via recovery IE on GTP-C signaling. P-GW shall ensure that
any dropped packets in this scenario are not charged and P-GW shall reject any bearer addition/modification request
received for the PDN connection maintained after the S-GW failure detection, till the time that PDN is restored again.
Important: If the S-GW Restoration feature is configured and enabled for a PGW that is associated with an
SAEGW service, the feature supports Pure-P calls only.
Once the session has been restored by the MME (i.e., P-GW receives a Modify Bearer Request from the restarted S-GW
or a different S-GW), P-GW shall resume forwarding any received downlink data and start charging them.
When subscriber is in S-GW restoration phase, all RARs (expect for Session Termination) will be rejected by PCEF. PGW will reject all internal updates which can trigger CCR-U towards PCRF. P-GW shall trigger a CCR U with ANGW-Change for the PDNs that are restored if the S-GW has changed on restoration.
Important: Only MME/S4-SGSN triggered S-GW restoration procedure will be supported. S-GW restoration
detection based on GTP-U path failure shall not be considered for this release. GTP-C path failure detection should be
enabled for enabling this feature.
MME/S4-SGSN is locally configured to know that P-GW in the same PLMN supports the S-GW restoration feature.
When this feature is enabled at P-GW, it shall support it for all S-GWs/MMEs.
For more details on this feature, refer to the S-GW Restoration Support chapter in this guide.
Source IP Address Validation
Insures integrity between the attached subscriber terminal and the PDN GW by mitigating the potential for unwanted
spoofing or man-in-the-middle attacks.
The P-GW includes local IPv4/IPv6 address pools for assigning IP addresses to UEs on a per-PDN basis. The P-GW
defends its provisioned address bindings by insuring that traffic is received from the host address that it has awareness
of. In the event that traffic is received from a non-authorized host, the P- GW includes the ability to block the nonauthorized traffic. The P-GW uses the IPv4 source address to verify the sender and the IPv6 source prefix in the case of
IPv6.
SRVCC PS-to-CS Handover Indication Support
This feature helps in notifying the PCRF about the exact reason for PCC rule deactivation o n Voice bearer deletion.
This exact cause will help PCRF to then take further action appropriately.
This feature ensures complete compliance for SRVCC, including support for PS-to-CS handover indication when voice
bearers are released. The support for SRVCC feature was first added in StarOS Release 12.2.
SRVCC service for LTE comes into the picture when a single radio User Equipment (UE) accessing IMS-anchored
voice call services switches from the LTE network to the Circuit Switched domain while it is able to transmit or receive
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on only one of these access networks at a given time. This removes the need for a UE to have multiple Radio Access
Technology (RAT) capability.
After handing over the PS sessions to the target, the source MME shall remove the voice b earers by deactivating the
voice bearer(s) towards S-GW/P-GW and setting the VB (Voice Bearer) flag of Bearer Flags IE in the Delete Bearer
Command message (TS 29.274 v9.5.0).
If the IP-CAN bearer termination is caused by the PS to CS handover, the PCEF may report related PCC rules for this
IP-CAN bearer by including the Rule-Failure-Code AVP set to the value PS_TO_CS_HANDOVER (TS 29.212 v10.2.0
and TS 23.203 v10.3.0).
Support for new AVP PS-to-CS-Session-Continuity (added in 3GPP Release 11) inside Charging Rule Install, which
indicates if the bearer is selected for PS to CS continuity, is not added.
Subscriber Level Trace
Provides a 3GPP standards-based session level trace function for call debugging and testing new functions and access
terminals in an LTE environment.
As a complement to Cisco's protocol monitoring function, the P-GW supports 3GPP standards based session level trace
capabilities to monitor all call control events on the respective monitored interfaces including S5/S8, S2a, SGi, and Gx.
The trace can be initiated using multiple methods:
 Management initiation via direct CLI configuration
 Management initiation at HSS with trace activation via authentication response messages over S6a reference
interface
 Signaling based activation through signaling from subscriber access terminal
Important: Once the trace is provisioned, it can be provisioned through the access cloud via various signaling
interfaces.
The session level trace function consists of trace activation followed by triggers. The time between the two events is
treated much like Lawful Intercept where the EPC network element buffers the trace activation instructions for the
provisioned subscriber in memory using camp-on monitoring. Trace files for active calls are buffered as XML files
using non-volatile memory on the local dual redundant hard drives on the ASR 5x00 platform. The Trace Depth defines
the granularity of data to be traced. Six levels are defined including Maximum, Minimum and Medium with ability to
configure additional levels based on vendor extensions.
All call control activity for active and recorded sessions is sent to an off-line Trace Collection Entity (TCE) using a
standards-based XML format over a FTP or secure FTP (SFTP) connection. In the current release the IPv4 interfaces are
used to provide connectivity to the TCE. Trace activation is based on IMSI or IMEI. Once a subscriber level trace
request is activated it can be propagated via the S5/S8 signaling to provision the corresponding trace for the same
subscriber call on the P-GW. The trace configuration will only be propagated if the P-GW is specified in the list of
configured Network Element types received by the S-GW. Trace configuration can be specified or transferred in any of
the following message types:
 S5/S8: Create Session Request
 S5/S8: Modify Bearer Request
 S5/S8: Trace Session Activation (New message defined in TS 32.422)
Performance Goals: As subscriber level trace is a CPU intensive activity the max number of concurrently monitored
trace sessions per Cisco P-GW is 32. Use in a production network should be restricted to minimize the impact on
existing services.
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3GPP tracing was enhanced in StarOS Release 15.0 to increase the number of simultaneous traces to 1000. The
generated trace files are forwarded to external trace collection entity at regular intervals through (S)FTP if “push” mode
is enabled. If the push mode is not used, the files are stored on the local hard drive and must be pulled off by the TCE
using FTP or SFTP.
Important: The number of session trace files generated would be limited by the total available hard disk
capacity.
3GPP Tracing to Intercept Random Subscriber
Previously, a subscriber identifier like IMSI was required in order to enable trace. Sometimes operators want to ena ble a
trace without knowing the subscriber ID. For example, an operator may want to monitor the next “n” number of calls, or
monitor subscribers in a particular IMSI range. The InTracer tool allows these use cases.
3GPP tracing was enhanced in StarOS Release 15.0 to intercept random subscribers with this feature. The current
session trace feature is either signaling or management based, which is very specific to a particular subscriber. The
requirement is to trace random subscribers which are not explicitly linked or identified by IMSI in GTP messages or
configured through CLI.
The random subscribers could be in an IMSI range, context activation in particular time intervals, etc.
The session trace is activated on demand for a limited period of time for specific analysis purposes. The maximum limit
would restrict the number of random subscriber tracing. Random session trace will be given priority over signalling and
management-based session trace.
Threshold Crossing Alerts (TCA) Support
Thresholding on the system is used to monitor the system for conditions that could potentially cause errors or outage.
Typically, these conditions are temporary (i.e high CPU utilization, or packet collisions on a network) and are quickly
resolved. However, continuous or large numbers of these error conditions within a specific time interval may be
indicative of larger, more severe issues. The purpose of thresholding is to help identify potentially severe conditions so
that immediate action can be taken to minimize and/or avoid system downtime.
The system supports Threshold Crossing Alerts for certain key resources such as CPU, memory, IP pool addresses, etc.
With this capability, the operator can configure threshold on these resources whereby, should the resource depletion
cross the configured threshold, a SNMP Trap would be sent.
The following thresholding models are supported by the system:
 Alert: A value is monitored and an alert condition occurs when the value reaches or exceeds the configured high
threshold within the specified polling interval. The alert is generated then generated and/or sent at the end of
the polling interval.
 Alarm: Both high and low threshold are defined for a value. An alarm condition occurs when the value reaches
or exceeds the configured high threshold within the specified polling interval. The alert is generated then
generated and/or sent at the end of the polling interval.
Thresholding reports conditions using one of the following mechanisms:
 SNMP traps: SNMP traps have been created that indicate the condition (high threshold crossing and/or clear) of
each of the monitored values.
Generation of specific traps can be enabled or disabled on the chassis. Ensuring that only important faults get
displayed. SNMP traps are supported in both Alert and Alarm modes.
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 Logs: The system provides a facility called threshold for which active and event logs can be generated. As with
other system facilities, logs are generated Log messages pertaining to the condition of a monitored value are
generated with a severity level of WARNING.
Logs are supported in both the Alert and the Alarm models.
 Alarm System: High threshold alarms generated within the specified polling interval are considered
“outstanding” until a the condition no longer exists or a condition clear alarm is generated. “Outstanding”
alarms are reported to the system's alarm subsystem and are viewable through the Alarm Management menu in
the Web Element Manager.
The Alarm System is used only in conjunction with the Alarm model.
Important: For more information on threshold crossing alert configuration, refer to the Thresholding
Configuration Guide.
UE Time Zone Reporting
This feature enables time-based charging for specialized service tariffs, such as super off-peak billing plans
Time Zone of the UE is associated with UE location (Tracking Area/Routing Area). The UE Time Zone Information
Element is an attribute the MME tracks on a Tracking Area List basis and propagates over S11 and S5/S8 signalling to
the P-GW.
Time zone reporting can be included in billing records or conveyed in Gx/Gy signaling to external PCRF and OCS
servers.
Virtual APN Support
Virtual APNs allow differentiated services within a single APN.
The Virtual APN feature allows a carrier to use a single APN to configure differentiated services. The APN that is
supplied by the MME is evaluated by the P-GW in conjunction with multiple configurable parameters. Then, the P-GW
selects an APN configuration based on the supplied APN and those configurable parameters.
APN configuration dictates all aspects of a session at the P-GW. Different policies imply different APNS. After basic
APN selection, however, internal re-selection can occur based on the following parameters:
 Service name
 Subscriber type
 MCC-MNC of IMSI
 Domain name part of username (user@domain)
 S-GW address
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P-GW Features and Functionality - Inline Service Support
This section describes the features and functions of inline services supported on the P-GW. These services require
additional licenses to implement the functionality.
Important: The SAEGW supports all of these features if a P-GW service is assigned to the SAEGW service.
This section describes the following features:
 Content Filtering
 Header Enrichment: Header Insertion and Encryption
 Mobile Video Gateway
 Network Address Translation (NAT)
 Peer-to-Peer Detection
 Personal Stateful Firewall
 Traffic Performance Optimization (TPO)
Content Filtering
The Cisco P-GW offers two variants of network-controlled content filtering / parental control services. Each approach
leverages the native DPI capabilities of the platform to detect and filter events of interest from mobile subscribers based
on HTTP URL or WAP/MMS URI requests:
 Integrated Content Filtering: A turnkey solution featuring a policy enforcement point and category based rating
database on the Cisco P-GW. An offboard AAA or PCRF provides the per-subscriber content filtering
information as subscriber sessions are established. The content filtering service uses DPI to extract URLs or
URIs in HTTP request messages and compares them against a static rating database to determine the category
match. The provisioned policy determines whether individual subscribers are entitled to view the content.
 Content Filtering ICAP Interface: This solution is appropriate for mobile operators with existing installations of
Active Content Filtering external servers. The service continues to harness the DPI functions of the ASR 5x00
platform to extract events of interest. However in this case, the extracted requests are transferred via the
Integrated Content Adaptation Protocol (ICAP) with subscriber identification information to the external ACF
server which provides the category rating database and content decision functions.
Integrated Adult Content Filter
Provides a value-added service to prevent unintended viewing of objectionable content that exploits underage children.
Content Filtering offers mobile operators a way to increase data ARPU and subscriber retention through a network based solution for parental controls and content filtering. The integrated solution enables a single policy decision and
enforcement point thereby streamlining the number of signaling interactions with external AAA/Policy Manager
servers. When used in parallel with other services such as Enhanced Content Charging (ECS) it increases billing
accuracy of charging records by insuring that mobile subscribers are only charged for visited sites they are allowed to
access.
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The Integrated Adult Content Filter is a subscriber-aware inline service provisioned on an ASR 5x00 running P-GW
services. Integrated Content Filtering utilizes the local DPI engine and harnesses a distributed software architecture that
scales with the number of active P-GW sessions on the system.
Content Filtering policy enforcement is the process of deciding if a subscriber should be able to receive some content.
Typical options are to allow, block, or replace/redirect the content based on the rating of the content and the policy
defined for that content and subscriber. The policy definition is transferred in an authentication response from a AAA
server or Diameter policy message via the Gx reference interface from an adjunct PCRF. The policy is applied to
subscribers through rulebase or APN/Subscriber configuration. The policy determines the action to be ta ken on the
content request on the basis of its category. A maximum of one policy can be associated with a rulebase.
ICAP Interface
Provides a value-added service to prevent unintended viewing of objectionable content that exploits underage children.
Content Filtering offers mobile operators a way to increase data ARPU and subscriber retention through a network based solution for parental controls and content filtering. The Content Filtering ICAP solution is appropriate for
operators with existing installations of Active Content Filtering servers in their networks.
The Enhanced Charging Service (ECS) for the P-GW provides a streamlined Internet Content Adaptation Protocol
(ICAP) interface to leverage the Deep Packet Inspection (DPI) to enable external Application Servers to provide their
services without performing the DPI functionality and without being inserted in the data flow. The ICAP interface may
be attractive to mobile operators that prefer to use an external Active Content Filtering (ACF) Platform. If a subscriber
initiates a WAP (WAP1.x or WAP2.0) or Web session, the subsequent GET/POST request is detected by the deep
packet inspection function. The URL of the GET/POST request is extracted by the local DPI engine on the ASR 5x00
platform and passed, along with subscriber identification information and the subscriber request, in an ICAP message to
the Application Server (AS). The AS checks the URL on the basis of its category and other classifications like, type,
access level, content category and decides if the request should be authorized, blocked or redirected by answering the
GET/POST message. Depending upon the response received from the ACF server, the P-GW either passes the request
unmodified or discards the message and responds to the subscriber with the appropriate redirection or block message.
Header Enrichment: Header Insertion and Encryption
Header enrichment provides a value-added capability for mobile operators to monetize subscriber intelligence to include
subscriber-specific information in the HTTP requests to application servers.
Extension header fields (x-header) are the fields that can be added to headers of a protocol for a specific purpose. The
enriched header allows additional entity-header fields to be defined without changing the protocol, but these fields
cannot be assumed to be recognizable by the recipient. Unrecognized fields should be ignored by the recipient and must
be forwarded by transparent proxies.
Extension headers can be supported in HTTP/WSP GET and POST requ est packets. The Enhanced Charging Service
(ECS) for the P-GW offers APN-based configuration and rules to insert x-headers in HTTP/WSP GET and POST
request packets. The charging action associated with the rules will contain the list of x -headers to be inserted in the
packets. Protocols supported are HTTP, WAP 1.0 and WAP 2.0 GET, and POST messages.
Important: For more information on ECS, see the Enhanced Charging Service Administration Guide.
The data passed in the inserted HTTP header attributes is used by end application servers (also known as Upsell
Servers) to identify subscribers and session information. These servers provide information customized to that specific
subscriber.
The Cisco P-GW can include the following information in the http header:
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 User-customizable, arbitrary text string
 Subscriber's MSISDN (the RADIUS calling-station-id, in clear text)
 Subscriber‘s IMSI
 Subscriber‘s IP address
 S-GW IP address (in clear text)
X-Header encryption enhances the header enrichment feature by increasing the number of fields that can be supported
and through encryption of the fields before inserting them.
The following limitations to insertion of x-header fields in WSP headers apply:
 x-header fields are not inserted in IP fragmented packets before StarOS v14.0.
 In case of concatenated request, x-header fields are only inserted in first GET or POST request (if rule matches
for the same). X-header fields are not inserted in the second or later GET/POST requests in the concatenated
requests. For example, if there is ACK+GET in packet, x-header is inserted in the GET packet. However, if
GET1+GET2 is present in the packet and rule matches for GET2 and not GET1 x -header is still inserted in
GET2. In case of GET+POST also, x-header is not inserted in POST.
 In case of CO, x-header fields are not inserted if the WTP packets are received out of order (even after proper
reordering).
 If route to MMS is present, x-headers are not inserted.
 x-headers are not inserted in WSP POST packet when header is segmented. This is because POST contains
header length field which needs to be modified after addition of x-headers. In segmented WSP headers, header
length field may be present in one packet and header may complete in another packet.
Mobile Video Gateway
The Cisco ASR 5x00 chassis provides mobile operators with a flexible solution that functions as a Mobile Video
Gateway in 2.5G, 3G, and 4G wireless data networks.
The Cisco Mobile Video Gateway consists of new software for the ASR 5x00. The Mobile Video Gateway is the central
component of the Cisco Mobile Videoscape. It employs a number of video optimization techniques that enable mobile
operators to enhance the video experience for their subscribers while optimizing the performance of video content
transmission through the mobile network.
The Mobile Video Gateway features and functions include:
 DPI (Deep Packet Inspection) to identify subscriber requests for video vs. non-video content
 Transparent video re-addressing to the Cisco CAE (Content Adaptation Engine) for retrieval of optimized video
content
 CAE load balancing of HTTP video requests among the CAEs in the server cluster
 Video optimization policy control for tiered subscriber services
 Video white-listing, which excludes certain video clips from video optimization
 Video pacing for “just in time” video downloading
 TCP link monitoring
 Dynamic inline transrating
 Dynamically-enabled TCP proxy
 Traffic performance optimization
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 N+1 redundancy support
 SNMP traps and alarms (threshold crossing alerts)
 Mobile video statistics
 Bulk statistics for mobile video
The Cisco CAE is an optional component of the Cisco Mobile Videoscape. It runs on the Cisco UCS (Unified
Computing System) platform and functions in a UCS server cluster to bring additional video optimization capabilities to
the Mobile Videoscape. For information about the features and functions of the Cisco CAE, see the CAE product
documentation.
Important: For more information on the Mobile Video Gateway, refer to the Mobile Video Gateway
Administration Guide.
Network Address Translation (NAT)
NAT translates non-routable private IP address(es) to routable public IP address(es) from a pool of public IP addresses
that have been designated for NAT. This enables to conserve on the number of public IP addresses required to
communicate with external networks, and ensures security as the IP address scheme for the internal network is masked
from external hosts, and each outgoing and incoming packet goes through the translation process.
NAT works by inspecting both incoming and outgoing IP datagrams and, as needed, modifying the source IP address
and port number in the IP header to reflect the configured NAT address mapping for outgoing datagrams. The reverse
NAT translation is applied to incoming datagrams.
NAT can be used to perform address translation for simple IP and mobile IP. NAT can be selectively applied/denied to
different flows (5-tuple connections) originating from subscribers based on the flows' L3/L4 characteristics—Source-IP,
Source-Port, Destination-IP, Destination-Port, and Protocol.
NAT supports the following mappings:
 One-to-One
 Many-to-One
Important: For more information on NAT, refer to the Network Address Translation Administration Guide.
NAT64 Support
This feature helps facilitate the co-existence and gradual transition to IPv6 addressing scheme in the networks. Use of
NAT64 requires that a valid license key be installed. Contact your Cisco account representative for information on how
to obtain a license.
With the dwindling IPv4 public address space and the growing need for more routable addresses, service providers and
enterprises will continue to build and roll out IPv6 networks. However, because of the broad scale IPv4 deployment, it
is not practical that the world changes to IPv6 overnight. There is need to protect the IPv4 investment combined with the
need to expand and grow the network will force IPv4 and IPv6 networks to co -exist together for a considerable period
of time and keep end-user experience seamless.
The preferred approaches are to run dual stacks (both IPv4 and IPv6) on the end hosts, dual stack routing protocols, and
dual stack friendly applications. If all of the above is available, then the end hosts will communicate natively using IPv6
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or IPv4 (using NAT). Tunneling through the IPv4 or IPv6 is the next preferred method to achieve communication
wherever possible. When all these options fail, translation is recommended.
Stateful NAT64 is a mechanism for translating IPv6 packets to IPv4 packets and v ice-versa. The system supports a
Stateful NAT64 translator based on IETF Behave WG drafts whose framework is described in draft-ietf-behave-v6v4framework-10. Stateful NAT64 is available as part of the existing NAT licenses from the current system
implementation. The NAT44 and NAT64 will co-exist on the chassis and share the resources needed for NATing.
Peer-to-Peer Detection
Allows operators to identify P2P traffic in the network and applying appropriate controlling functions to ensure fair
distribution of bandwidth to all subscribers.
Peer-to-Peer (P2P) is a term used in two slightly different contexts. At a functional level, it means protocols that interact
in a peering manner, in contrast to client-server manner. There is no clear differentiation between the function of one
node or another. Any node can function as a client, a server, or both—a protocol may not clearly differentiate between
the two. For example, peering exchanges may simultaneously include client and server functionality, sending and
receiving information.
Detecting peer-to-peer protocols requires recognizing, in real time, some uniquely identifying characteristic of the
protocols. Typical packet classification only requires information uniquely typed in the packet header of packets of the
stream(s) running the particular protocol to be identified. In fact, many peer-to-peer protocols can be detected by simple
packet header inspection. However, some P2P protocols are different, preventing detection in the traditional manner.
This is designed into some P2P protocols to purposely avoid detection. The creators of these protocols purposely do not
publish specifications. A small class of P2P protocols is stealthier and more challenging to detect. For some protocols
no set of fixed markers can be identified with confidence as unique to the protocol.
Operators care about P2P traffic because of the behavior of some P2P applications (for example, Bittorrent, Skype, and
eDonkey). Most P2P applications can hog the network bandwidth such that 20% P2P users can generate as much as
traffic generated by the rest 80% non-P2P users. This can result into a situation where non-P2P users may not get
enough network bandwidth for their legitimate use because of excess usage of bandwidth by the P2P users. Network
operators need to have dynamic network bandwidth / traffic management functions in place to ensure fair distributions
of the network bandwidth among all the users. And this would include identifying P2P traffic in the network and
applying appropriate controlling functions to the same (for example, content-based premium billing, QoS modifications,
and other similar treatments).
Cisco’s P2P detection technology makes use of innovative and highly accurate protocol behavioral detection techniques.
Important: For more information on peer-to-peer detection, refer to the Application Detection and Control
Administration Guide.
Personal Stateful Firewall
The Personal Stateful Firewall is an in-line service feature that inspects subscriber traffic and performs IP session-based
access control of individual subscriber sessions to protect the subscribers from malicious security attacks.
The Personal Stateful Firewall supports stateless and stateful inspection and filtering based on the configuration.
In stateless inspection, the firewall inspects a packet to determine the 5-tuple—source and destination IP addresses and
ports, and protocol—information contained in the packet. This static information is then compared against configurable
rules to determine whether to allow or drop the packet. In stateless inspection the firewall examines each packet
individually, it is unaware of the packets that have passed through before it, and has no way of knowing if any given
packet is part of an existing connection, is trying to establish a new connection, or is a rogue pa cket.
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In stateful inspection, the firewall not only inspects packets up through the application layer / layer 7 determining a
packet's header information and data content, but also monitors and keeps track of the connection's state. For all active
connections traversing the firewall, the state information, which may include IP addresses and ports involved, the
sequence numbers and acknowledgement numbers of the packets traversing the connection, TCP packet flags, etc. is
maintained in a state table. Filtering decisions are based not only on rules but also on the connection state established by
prior packets on that connection. This enables to prevent a variety of DoS, DDoS, and other security violations. Once a
connection is torn down, or is timed out, its entry in the state table is discarded.
The Enhanced Charging Service (ECS) / Active Charging Service (ACS) in -line service is the primary vehicle that
performs packet inspection and charging. For more information on ECS, see the Enhanced Charging Service
Administration Guide.
Important: For more information on Personal Stateful Firewall, refer to the Personal Stateful Firewall
Administration Guide.
Traffic Performance Optimization (TPO)
Though TCP is a widely accepted protocol in use today, it is optimized only for wired networks. Due to inherent
reliability of wired networks, TCP implicitly assumes that any packet loss is due to network congestion and
consequently invokes congestion control measures. However, wireless links are known to experience sporadic and
usually temporary losses due to several reasons, including the following, which also trigger TCP congestion control
measures resulting in poor TCP performance.
Reasons for delay variability over wireless links include:
 Channel fading effect, subscriber mobility, and other transient conditions
 Link-layer retransmissions
 Handoffs between neighboring cells
 Intermediate nodes, such as SGSN and e-NodeB, implementing scheduling polices tuned to deliver better QoS
for select services; resulting is variable delay in packet delivery for other services
The TPO inline service uses a combination of TCP and HTTP optimization techniques to improve TCP performance
over wireless links.
Important: For more information on TPO, refer to the Traffic Performance Optimization Administration Guide.
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Features and Functionality - External Application Support
This section describes the features and functions of external applications supported on the S-GW and P-GW. These
services require additional licenses to implement the functionality.
Important: The SAEGW supports all of these features if an S-GW and/or P-GW service is assigned to the
SAEGW service.
This section describes the following feature(s):
 Web Element Management System
Web Element Management System
Provides a graphical user interface (GUI) for performing fault, configuration, accounting, performance, and security
(FCAPS) management of the ASR 5x00.
The Web Element Manager is a Common Object Request Broker Architecture (CORBA)-based application that
provides complete fault, configuration, accounting, performance, and security (FCAPS) management capability for th e
system.
For maximum flexibility and scalability, the Web Element Manager application implements a client -server architecture.
This architecture allows remote clients with Java-enabled web browsers to manage one or more systems via the server
component which implements the CORBA interfaces. The server component is fully compatible with the fault -tolerant
Sun® Solaris® operating system.
The following figure demonstrates various interfaces between the Cisco Web Element Manager and other network
components.
Figure 14.
Web Element Manager Network Interfaces
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Important: For more information on WEM support, refer to the WEM Installation and Administration Guide.
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S-GW Features and Functionality - Optional Enhanced Feature
Software
This section describes the optional enhanced features and functions for the S-GW service.
Important: The SAEGW supports all of these features if an S-GW service is assigned to the SAEGW service.
Each of the following features require the purchase of an additional license to implement the functionality with the SGW service.
This section describes the following features:
 Always-On Licensing
 Direct Tunnel
 Intelligent Paging for ISR
 Inter-Chassis Session Recovery
 IP Security (IPSec) Encryption
 Lawful Intercept
 Layer 2 Traffic Management (VLANs)
 Session Recovery Support
Always-On Licensing
Use of Always On Licensing requires that a valid license key be installed. Contact your Cisco account representative for
information on how to obtain a license.
Traditionally, transactional models have been based on registered subscriber sessions. In an “always-on” deployment
model, however, the bulk of user traffic is registered all of the time. Most of these registered subscriber sessions are idle
a majority of the time. Therefore, Always-On Licensing charges only for connected-active subscriber sessions.
A connected-active subscriber session would be in “ECM Connected state,” as specified in 3GPP TS 23.401, with a data
packet sent/received within the last one minute (on average). This transactional model allows providers to better manage
and achieve more predictable spending on their capacity as a function of the Total Cost of Ownership (TCO).
Direct Tunnel
In accordance with standards, one tunnel functionality enables the SGSN to establish a direct tunnel at the user plane
level - a GTP-U tunnel, directly between the RAN and the S-GW.
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Figure 15.
GTP-U with Direct Tunnel
In effect, a direct tunnel reduces data plane latency as the tunnel functionality acts to remove the SGSN from the data
plane and limit the SGSN to the control plane for processing. This improves the user experience (for example, expedites
web page delivery, reduces round trip delay for conversational services). Additionally, direct tunnel functionality
implements the standard SGSN optimization to improve the usage of user plane resources (and hardware) by removing
the requirement from the SGSN to handle the user plane processing.
Typically, the SGSN establishes a direct tunnel at PDP context activation using an Update PDP Context Request
towards the S-GW. This means a significant increase in control plane load on both the SGSN and S-GW components of
the packet core. Hence, deployment requires highly scalable S-GWs since the volume and frequency of Update PDP
Context messages to the S-GW will increase substantially. The ASR 5x00 platform capabilities ensure control plane
capacity will not be a limiting factor with direct tunnel deployment.
For more information on Direct Tunnel configuration, refer to the Direct Tunnel Configuration appendix in this guide.
Intelligent Paging for ISR
In case of Idle-mode Signaling Reduction (ISR) active and UE is idle, the S-GW will send Downlink Data Notification
(DDN) Message to both the MME and the S4-SGSN if it receives the downlink data or network initiated control
message for this UE. In turn, the MME and the S4-SGSN would do paging in parallel consuming radio resources.
To optimize the radio resource, the S-GW will now perform intelligent paging. When configured at S-GW service level
for each APN, the S-GW will page in a semi-sequential fashion (one by one to peer MME or S4-SGSN based on last
known RAT type) or parallel to both the MME and S4-SGSN.
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Inter-Chassis Session Recovery
The ASR 5x00 platform provide industry leading carrier class redundancy. The systems protects against all single points
of failure (hardware and software) and attempts to recover to an operational state when multiple simultaneous failures
occur.
The system provides several levels of system redundancy:
 Under normal N+1 PSC hardware redundancy, if a catastrophic PSC failure occurs all affected calls are migrated
to the standby PSC if possible. Calls which cannot be migrated are gracefully terminated with proper call termination signaling and accounting records are generated with statistics accurate to th e last internal
checkpoint
 If the Session Recovery feature is enabled, any total PSC failure will cause a PSC switchover and all established
sessions for supported call-types are recovered without any loss of session.
Even though Cisco provides excellent intra-chassis redundancy with these two schemes, certain catastrophic failures
which can cause total chassis outages, such as IP routing failures, line-cuts, loss of power, or physical destruction of the
chassis, cannot be protected by this scheme. In such cases, the MME Inter-Chassis Session Recovery (ICSR) feature
provides geographic redundancy between sites. This has the benefit of not only providing enhanced subscriber
experience even during catastrophic outages, but can also protect other systems such as the RAN from subscriber reactivation storms.
ICSR allows for continuous call processing without interrupting subscriber services. This is accomplished through the
use of redundant chassis. The chassis are configured as primary and backup with one being active and one in recovery
mode. A checkpoint duration timer is used to control when subscriber data is sent from the active chassis to the inactive
chassis. If the active chassis handling the call traffic goes out of service, the inactive chassis transiti ons to the active
state and continues processing the call traffic without interrupting the subscriber session. The chassis determines which
is active through a propriety TCP-based connection called a redundancy link. This link is used to exchange Hello
messages between the primary and backup chassis and must be maintained for proper system operation.
Interchassis Communication
Chassis configured to support ICSR communicate using periodic Hello messages. These messages are sent by each
chassis to notify the peer of its current state. The Hello message contains information about the chassis such as its
configuration and priority. A dead interval is used to set a time limit for a Hello message to be received from the chassis'
peer. If the standby chassis does not receive a Hello message from the active chassis within the dead interval, the
standby chassis transitions to the active state. In situations where the redundancy link goes out of service, a priority
scheme is used to determine which chassis processes the session. The following priority scheme is used:
 router identifier
 chassis priority
 SPIO MAC address
Checkpoint Messages
Checkpoint messages are sent from the active chassis to the inactive chassis. Checkpoint messages are sent at specific
intervals and contain all the information needed to recreate the sessions on the standby chassis, if that chassis were to
become active. Once a session exceeds the checkpoint duration, checkpoint data is collected on the session. The
checkpoint parameter determines the amount of time a session must be active before it is included in the checkpoint
message.
Important: For more information on inter-chassis session recovery support, refer to the Interchassis Session
Recovery appendix in System Administration Guide.
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IP Security (IPSec) Encryption
Enables network domain security for all IP packet switched LTE-EPC networks in order to provide confidentiality,
integrity, authentication, and anti-replay protection. These capabilities are insured through use of cryptographic
techniques.
The Cisco S-GW supports IKEv1 and IPSec encryption using IPv4 addressing. IPSec enables the following two use
cases:
 Encryption of S8 sessions and EPS bearers in roaming applications where the P-GW is located in a separate
administrative domain from the S-GW
 IPSec ESP security in accordance with 3GPP TS 33.210 is provided for S1 control plane, S1 bearer plane and S1
management plane traffic. Encryption of traffic over the S1 reference interface is desirable in cases where the
EPC core operator leases radio capacity from a roaming partner's network.
Important: You must purchase an IPSec license to enable IPSec. For more information on IPSec support, refer to
the Cisco StarOS IP Security (IPSec) Reference.
Lawful Intercept
The Cisco Lawful Intercept feature is supported on the S-GW. Lawful Intercept is a licensed-enabled, standards-based
feature that provides telecommunications service providers with a mechanism to assist law enforcement agencies in
monitoring suspicious individuals for potential illegal activity. For additional information and documentation on the
Lawful Intercept feature, contact your Cisco account representative.
Layer 2 Traffic Management (VLANs)
Virtual LANs (VLANs) provide greater flexibility in the configuration and use of contexts and services.
VLANs are configured as tags on a per-port basis and allow more complex configurations to be implemented. The
VLAN tag allows a single physical port to be bound to multiple logical interfaces that can be configured in different
contexts. Therefore, each Ethernet port can be viewed as containing many logical ports when VLAN tags are employed.
Important: For more information on VLAN support, refer to the VLANs appendix in the System Administration
Guide.
Session Recovery Support
Provides seamless failover and reconstruction of subscriber session information in the event of a hardware or software
fault within the system preventing a fully connected user session from being disconnected.
In the telecommunications industry, over 90 percent of all equipment failures are software-related. With robust
hardware failover and redundancy protection, any card-level hardware failures on the system can quickly be corrected.
However, software failures can occur for numerous reasons, many times without prior indication. StarOS has the ability
to support stateful intra-chassis session recovery (ICSR) for S-GW sessions.
When session recovery occurs, the system reconstructs the following subscriber information:
 Data and control state information required to maintain correct call behavior
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 Subscriber data statistics that are required to ensure that accounting information is maintained
 A best-effort attempt to recover various timer values such as call duration, absolute time, and others
Session recovery is also useful for in-service software patch upgrade activities. If session recovery is enabled during the
software patch upgrade, it helps to preserve existing sessions on the active packet services card during the upgrade
process.
Important: For more information on session recovery support, refer to the Session Recovery appendix in the
System Administration Guide.
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P-GW Features and Functionality - Optional Enhanced Feature
Software
This section describes the optional enhanced features and functions for the P-GW service.
Important: The SAEGW supports all of these features if a P-GW service is assigned to the SAEGW service.
Each of the following features requires the purchase of an additional license to implement the functionality with the PGW service.
Important: For information on installing and verifying licenses, refer to the Managing License Keys section of
the Software Management Operations chapter in the System Administration Guide.
This section describes the following features:
 Always-On Licensing
 Dynamic RADIUS Extensions (Change of Authorization)
 GRE Protocol Interface Support
 GTP Throttling
 Inter-Chassis Session Recovery
 IP Security (IPSec) Encryption
 L2TP LAC Support
 Lawful Intercept
 Layer 2 Traffic Management (VLANs)
 Local Policy Decision Engine
 MPLS Forwarding with LDP
 NEMO Service Supported
 Session Recovery Support
 Smartphone Tethering Detection Support
 Traffic Policing
 User Location Information Reporting
Always-On Licensing
Use of Always On Licensing requires that a valid license key be installed. Contact your Cisco account representative for
information on how to obtain a license.
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Traditionally, transactional models have been based on registered subscriber sessions. In an “always-on” deployment
model, however, the bulk of user traffic is registered all of the time. Most of these registered subscriber sessions are idle
a majority of the time. Therefore, Always-On Licensing charges only for connected-active subscriber sessions.
A connected-active subscriber session would be in “ECM Connected state,” as specified in 3GPP TS 23.401, with a data
packet sent/received within the last one minute (on average). This transactional model allows providers to better manage
and achieve more predictable spending on their capacity as a function of the Total Cost of Ownership (TCO).
Dynamic RADIUS Extensions (Change of Authorization)
Use of Dynamic RADIUS Extensions (CoA and PoD) requires that a valid license key be installed. Contact your Ci sco
account representative for information on how to obtain a license.
Dynamic RADIUS extension support provide operators with greater control over subscriber PDP contexts by providing
the ability to dynamically redirect data traffic, and or disconnect the PDP context.
This functionality is based on the RFC 3576, Dynamic Authorization Extensions to Remote Authentication Dial In User
Service (RADIUS), July 2003 standard.
The system supports the configuration and use of the following dynamic RADIUS extensions:
 Change of Authorization: The system supports CoA messages from the AAA server to change data filters
associated with a subscriber session. The CoA request message from the AAA server must contain attributes to
identify NAS and the subscriber session and a data filter ID for the data filter to apply to the subscriber session.
 Disconnect Message: The DM message is used to disconnect subscriber sessions in the system from a RADIUS
server. The DM request message should contain necessary attributes to identify the subscriber session.
The above extensions can be used to dynamically re-direct subscriber PDP contexts to an alternate address for
performing functions such as provisioning and/or account set up. This functionality is referred to as Session Redirection,
or Hotlining.
Session redirection provides a means to redirect subscriber traffic to an external server by applying ACL rules to the
traffic of an existing or a new subscriber session. The destination address and optionally the destination port of TCP/IP
or UDP/IP packets from the subscriber are rewritten so the packet is forwarded to the designated redirected address.
Return traffic to the subscriber has the source address and port rewritten to the original values. The redirect ACL may be
applied dynamically by means of the Radius Change of Authorization (CoA) extension.
Important: For more information on dynamic RADIUS extensions support, refer to the CoA, RADIUS, And
Session Redirection (Hotlining) appendix in this guide.
GRE Protocol Interface Support
Use of GRE Interface Tunneling requires that a valid license key be installed. Contact your local Sales or Support
representative for information on how to obtain a license.
The P-GW supports GRE generic tunnel interfaces in accordance with RFC 2784, Generic Routing Encapsulation
(GRE). The GRE protocol allows mobile users to connect to their enterprise networks through GRE tunnel s.
GRE tunnels can be used by the enterprise customers of a carrier 1) To transport AAA packets corresponding to an APN
over a GRE tunnel to the corporate AAA servers and, 2) To transport the enterprise subscriber packets over the GRE
tunnel to the corporation gateway.
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The corporate servers may have private IP addresses and hence the addresses belonging to different enterprises may be
overlapping. Each enterprise needs to be in a unique virtual routing domain, known as VRF. To differentiate the tunnels
between same set of local and remote ends, GRE Key will be used as a differentiation.
GRE tunneling is a common technique to enable multi-protocol local networks over a single-protocol backbone, to
connect non-contiguous networks and allow virtual private networks across WANs. This mechanism encapsulates data
packets from one protocol inside a different protocol and transports the data packets unchanged across a foreign
network. It is important to note that GRE tunneling does not provide security to the encapsulated protocol, as there is no
encryption involved (like IPSec offers, for example).
GRE tunneling consists of three main components:
 Passenger protocol-protocol being encapsulated. For example: CLNS, IPv4 and IPv6.
 Carrier protocol-protocol that does the encapsulating. For example: GRE, IP-in-IP, L2TP, MPLS and IPSec.
 Transport protocol-protocol used to carry the encapsulated protocol. The main transport protocol is IP.
Important: For more information on GRE protocol interface support, refer to the GRE Protocol Interface
appendix in this guide.
GTP Throttling
Use of GTP and Diameter Interface Throttling requires that a valid license key be installed. Contact your Cisco account
representative for information on how to obtain a license.
This feature will help control the rate of incoming/outgoing messages on P-GW/GGSN. This will help in ensuring PGW/GGSN doesn’t get overwhelmed by the GTP control plan messages. In addition, it will help in ensuring the PGW/GGSN will not overwhelm the peer GTP-C peer with GTP Control plane messages.
This feature requires shaping/policing of GTP (v1 and v2) control messages over Gn/Gp and S5/S8 interfaces. Feature
will cover overload protection of P-GW/GGSN nodes and other external nodes with which it communicates. Throttling
would be done only for session level control messages. Path management messages would not be rate limited at all.
External node overload can happen in a scenario where P-GW/GGSN generates signaling requests at a higher rate than
other nodes can handle. Also, if the incoming rate is high at P-GW/GGSN node, we might flood any of the external
nodes; hence, throttling of both incoming and outgoing control messages is required.
For protecting external nodes from getting overloaded from P-GW/GGSN control signaling, a framework will be used
to handle shaping/policing of outbound control messages to external interfaces.
Inter-Chassis Session Recovery
Use of Interchassis Session Recovery requires that a valid license key be installed. Contact your local Sales or Support
representative for information on how to obtain a license.
The ASR 5x00 provides industry leading carrier class redundancy. The systems protects against all single points of
failure (hardware and software) and attempts to recover to an operational state when multiple simultaneous failures
occur.
The system provides several levels of system redundancy:
 Under normal N+1 PSC/PSC2 hardware redundancy, if a catastrophic packet processing card failure occurs all
affected calls are migrated to the standby packet processing card if possible. Calls which cannot be migrated
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are gracefully terminated with proper call-termination signaling and accounting records are generated with
statistics accurate to the last internal checkpoint
 If the Session Recovery feature is enabled, any total PSC/PSC2 failure will cause a PSC switchover and all
established sessions for supported call-types are recovered without any loss of session.
Even though Cisco provides excellent intra-chassis redundancy with these two schemes, certain catastrophic failures
which can cause total chassis outages, such as IP routing failures, line-cuts, loss of power, or physical destruction of the
chassis, cannot be protected by this scheme. In such cases, the MME Inter-Chassis Session Recovery feature provides
geographic redundancy between sites. This has the benefit of not only providing enhanced subscriber experience even
during catastrophic outages, but can also protect other systems such as the RAN from subscriber re-activation storms.
The Interchassis Session Recovery feature allows for continuous call processing without interrupting subscriber
services. This is accomplished through the use of redundant chassis. The chassis are configured as primary and backup
with one being active and one in recovery mode. A checkpoint duration timer is used to control when subscriber data is
sent from the active chassis to the inactive chassis. If the active chassis handling the call traffic goes out of service, th e
inactive chassis transitions to the active state and continues processing the call traffic without interrupting the subscriber
session. The chassis determines which is active through a propriety TCP-based connection called a redundancy link.
This link is used to exchange Hello messages between the primary and backup chassis and must be maintained for
proper system operation.
 Interchassis Communication
Chassis configured to support Interchassis Session Recovery communicate using periodic Hello messages.
These messages are sent by each chassis to notify the peer of its current state. The Hello message contains
information about the chassis such as its configuration and priority. A dead interval is used to set a time limit
for a Hello message to be received from the chassis' peer. If the standby chassis does not receive a Hello
message from the active chassis within the dead interval, the standby chassis transitions to the active state. In
situations where the redundancy link goes out of service, a priority scheme is used to determine which chassis
processes the session. The following priority scheme is used:
 router identifier
 chassis priority
 SPIO MAC address
 Checkpoint Messages
Checkpoint messages are sent from the active chassis to the inactive chassis. Checkpoint messages are sent at
specific intervals and contain all the information needed to recreate the sessions on the standby chassis, if that
chassis were to become active. Once a session exceeds the checkpoint duration, checkpoint data is collected on
the session. The checkpoint parameter determines the amount of time a session must be active before it is
included in the checkpoint message.
Important: For more information on inter-chassis session recovery support, refer to the Interchassis Session
Recovery chapter in the System Administration Guide.
IP Security (IPSec) Encryption
Use of Network Domain Security requires that a valid license key be installed. Contact your local Sales or Support
representative for information on how to obtain a license.
IPSec encryption enables network domain security for all IP packet switched LTE-EPC networks in order to provide
confidentiality, integrity, authentication, and anti-replay protection. These capabilities are insured through use of
cryptographic techniques.
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The Cisco P-GW supports IKEv1 and IPSec encryption using IPv4 addressing. IPSec enables the following two use
cases:
 Encryption of S8 sessions and EPS bearers in roaming applications where the P-GW is located in a separate
administrative domain from the S-GW
 IPSec ESP security in accordance with 3GPP TS 33.210 is provided for S1 control plane, S1 bearer plane and S1
management plane traffic. Encryption of traffic over the S1 reference interface is desirable in cases where the
EPC core operator leases radio capacity from a roaming partner's network.
Important: For more information on IPSec support, refer to the Cisco StarOS IP Security (IPSec) Reference.
L2TP LAC Support
Use of L2TP LAC requires that a valid license key be installed. Contact your local Sales or Support representative for
information on how to obtain a license.
The system configured as a Layer 2 Tunneling Protocol Access Concentrator (LAC) enables communication with L2TP
Network Servers (LNSs) for the establishment of secure Virtual Private Network (VPN) tunnels between the operator
and a subscriber's corporate or home network.
The use of L2TP in VPN networks is often used as it allows the corporation to have more control over authentication
and IP address assignment. An operator may do a first level of authentication, however use PPP to exchange user name
and password, and use IPCP to request an address. To support PPP negotiation between the P-GW and the corporation,
an L2TP tunnel must be setup in the P-GW running a LAC service.
L2TP establishes L2TP control tunnels between LAC and LNS before tunneling the subscriber PPP connections as
L2TP sessions. The LAC service is based on the same architecture as the P-GW and benefits from dynamic resource
allocation and distributed message and data processing.
The LAC sessions can also be configured to be redundant, thereby mitigating any impact of hardware or software
issues. Tunnel state is preserved by copying the information across processor cards.
Important: For more information on this feature support, refer to the L2TP Access Concentrator appendix in this
guide.
Lawful Intercept
The feature use license for Lawful Intercept on the P-GW is included in the P-GW session use license.
The Cisco Lawful Intercept feature is supported on the P-GW. Lawful Intercept is a licensed-enabled, standards-based
feature that provides telecommunications service providers with a mechanism to assist law enforcement agencies in
monitoring suspicious individuals for potential illegal activity. For additional information and documentation on the
Lawful Intercept feature, contact your Cisco account representative.
Layer 2 Traffic Management (VLANs)
Use of Layer 2 Traffic Management requires that a valid license key be installed. Contact your local Sales or Support
representative for information on how to obtain a license.
Virtual LANs (VLANs) provide greater flexibility in the configuration and use of contexts and services.
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VLANs are configured as “tags” on a per-port basis and allow more complex configurations to be implemented. The
VLAN tag allows a single physical port to be bound to multiple logical interfaces that can be configured in different
contexts; therefore, each Ethernet port can be viewed as containing many logical ports when VLAN tags are employed.
Important: For more information on VLAN support, refer to the VLANs chapter in the System Administration
Guide.
Local Policy Decision Engine
Use of the Local Policy Decision Engine requires that a valid license key be installed. Contact your local Sales or
Support representative for information on how to obtain a license.
The Local Policy Engine is an event-driven rules engine that offers Gx-like QoS and policy controls to enable user or
application entitlements. As the name suggests, it is designed to provide a subset of a PCRF in cases where an operator
elects not to use a PCRF or scenarios where connections to an external PCRF are disrupted. Local policies are used to
control different aspects of a session like QoS, data usage, subscription profiles, and server usage by means of locally
defined policies. A maximum of 1,024 local policies can be provisioned on a P-GW system.
Local policies are triggered when certain events occur and the associated conditions are satisfied. For example, when a
new call is initiated, the QoS to be applied for the call could be decided based on the IMSI, MSISDN, and APN.
Potential uses cases for the Local Policy Decision Engine include:
 Disaster recovery data backup solution in the event of a loss of PCRF in a mobile core network.
 Dedicated bearer establishment for emergency voice calls.
 Network-initiated bearer establishment on LTE to non-3GPP inter-domain handovers.
Important: For more information on configuring the Local Policy Decision Engine, refer to the Configuring
Local QoS Policy section in the PDN Gateway Configuration chapter of this guide.
MPLS Forwarding with LDP
Use of MPLS requires that a valid license key be installed. Contact your local Sales or Support representative for
information on how to obtain a license.
Multi Protocol Label Switching (MPLS) is an operating scheme or a mechanism that is used to speed up the flow of
traffic on a network by making better use of available network paths. It works with the routing protocols like BGP and
OSPF, and therefore it is not a routing protocol.
MPLS generates a fixed-length label to attach or bind with the IP packet's header to control the flow and destination of
data. The binding of the labels to the IP packets is done by the label distribution protocol (LDP). All the packets in a
forwarding equivalence class (FEC) are forwarded by a label-switching router (LSR), which is also called an MPLS
node. The LSR uses the LDP in order to signal its forwarding neighbors and distribute i ts labels for establishing a label
switching path (LSP).
In order to support the increasing number of corporate APNs, which have a number of different addressing models and
requirements, MPLS is deployed to fulfill at least the following two requirements:
 The corporate APN traffic must remain segregated from other APNs for security reasons.
 Overlapping of IP addresses in different APNs.
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When deployed, the MPLS backbone automatically negotiates routes using the labels binded with the IP packets. Cisco
P-GW as an LSR learns the default route from the connected provider edge (PE), while the PE populates its routing
table with the routes provided by the P-GW.
Important: For more information on MPLS support, refer to the Multi-Protocol Label Switching (MPLS)
Support appendix in this guide.
NEMO Service Supported
Use of NEMO requires that a valid license key be installed. Contact your local Sales or Support representative for
information on how to obtain a license.
The P-GW may be configured to enable or disable Network Mobility (NEMO) service.
When enabled, the system includes NEMO support for a Mobile IPv4 Network Mobility (NEMO-HA) on the P-GW
platform to terminate Mobile IPv4 based NEMO connections from Mobile Routers (MRs) that attach to an Enterprise
PDN. The NEMO functionality allows bi-directional communication that is application-agnostic between users behind
the MR and users or resources on Fixed Network sites.
The same NEMO4G-HA service and its bound Loopback IP address supports NEMO connections whose underlying
PDN connection comes through GTP S5 (4G access) or PMIPv6 S2a (eHRPD access).
Important: For more information on NEMO support, refer to the Network Mobility (NEMO) chapter in this
guide.
NEMO Support in GGSN
Use of Dynamic Network Mobile Routing (NEMO) for GGSN requires that a valid license key be i nstalled. Contact
your Cisco account representative for information on how to obtain a license.
This feature now supports standards-based NEMO feature on GGSN, which allows operators to support Enterprise VPN
service with the advantage of faster deployment and flexible bandwidth arrangement for customers.
NEMO (NEtwork MObility) provides wireless connectivity between enterprise core network and remote sites over
3G/4G network. The wireless connection can be used as either primary link or backup link. All th e hosts in the remote
site can directly communicate with hosts in the core network without using NAT.
Enterprise VPN service is one of the main use case for this feature. Fast deployment and flexible bandwidth
arrangement for customers are some of the advantages of this service. Customers include banks, financial institutions,
multi-sited enterprises, city public safety departments, transportation fleet, etc.
NEMO support in P-GW was added in earlier StarOS releases. In release 15.0, support was added for GGSN as well so
that NEMO can be supported for subscribers roaming out on 3G (UMTS/GERAN) networks.
Session Recovery Support
The feature use license for Session Recovery on the P-GW is included in the P-GW session use license.
Session recovery provides seamless failover and reconstruction of subscriber session information in the event of a
hardware or software fault within the system preventing a fully connected user session from being disconnected.
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In the telecommunications industry, over 90 percent of all equipment failures are software-related. With robust
hardware failover and redundancy protection, any card-level hardware failures on the system can quickly be corrected.
However, software failures can occur for numerous reasons, many times without prior indication. StarOS Release 9.0
adds the ability to support stateful intra-chassis session recovery for P-GW sessions.
When session recovery occurs, the system reconstructs the following subscriber information:
 Data and control state information required to maintain correct call behavior
 Subscriber data statistics that are required to ensure that accounting information is maintained
 A best-effort attempt to recover various timer values such as call duration, absolute time, and others
Session recovery is also useful for in-service software patch upgrade activities. If session recovery is enabled during the
software patch upgrade, it helps to preserve existing sessions on the active PSC/PSC2 during the upgrade process.
Important: For more information on session recovery support, refer to the Session Recovery chapter in the
System Administration Guide.
Smartphone Tethering Detection Support
Use of Smartphone Tethering Detection requires that a valid license key be installed. Contact your local Sales or
Support representative for information on how to obtain a license.
On the P-GW, using the inline heuristic detection mechanism, it is now possible to detect and differentiate between the
traffic from the mobile device and a tethered device connected to the mobile device.
Traffic Policing
Use of Per-Subscriber Traffic Policing requires that a valid license key be installed. Contact your local Sales or Support
representative for information on how to obtain a license.
Traffic policing allows you to manage bandwidth usage on the network and limit bandwidth allowances to subscribers.
Traffic policing enables the configuring and enforcing of bandwidth limitations on individual subscribers and/or APNs
of a particular traffic class in 3GPP/3GPP2 service.
Bandwidth enforcement is configured and enforced independently on the downlink and the uplink directions.
A Token Bucket Algorithm (a modified trTCM) [RFC2698] is used to implement the Traffic-Policing feature. The
algorithm used measures the following criteria when determining how to mark a packet:
 Committed Data Rate (CDR): The guaranteed rate (in bits per second) at which packets can be
transmitted/received for the subscriber during the sampling interval.
 Peak Data Rate (PDR): The maximum rate (in bits per second) that subscriber packets can be
transmitted/received for the subscriber during the sampling interval.
 Burst-size: The maximum number of bytes that can be transmitted/received for the subscriber during the
sampling interval for both committed (CBS) and peak (PBS) rate conditions. This represents the maximum
number of tokens that can be placed in the subscriber’s “bucket”. Note that the committed burst size (CBS)
equals the peak burst size (PBS) for each subscriber.
The system can be configured to take any of the following actions on packets that are determined to be in excess or in
violation:
 Drop: The offending packet is discarded.
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 Transmit: The offending packet is passed.
 Lower the IP Precedence: The packet’s ToS bit is set to “0”, thus downgrading it to Best Effort, prior to
passing the packet. Note that if the packet’s ToS bit was already set to “0”, this action is equivalent to
“Transmit”.
Important: For more information on traffic policing, refer to the Traffic Policing and Shaping appendix in this
guide.
User Location Information Reporting
Use of User Location Information (ULI) Reporting requires that a valid license key be installed. Contact your local
Sales or Support representative for information on how to obtain a license.
ULI Reporting allows the eNodeB to report the location of a UE to the MME, when requested by a P-GW.
The following procedures are used over the S1-MME interface to initiate and stop location reporting between the MME
and eNodeB:
 Location Reporting Control: The purpose of Location Reporting Control procedure is to allow the MME to
request that the eNodeB report where the UE is currently located. This procedure uses UE-associated signaling.
 Location Report Failure Indication: The Location Report Failure Indication procedure is initiated by an
eNodeB in order to inform the MME that a Location Reporting Control procedure has failed. This procedure
uses UE-associated signalling.
 Location Report: The purpose of Location Report procedure is to provide the UE's current location to the
MME. This procedure uses UE-associated signalling.
The start/stop trigger for location reporting for a UE is reported to the MME by the S-GW over the S11 interface. The
Change Reporting Action (CRA) Information Element (IE) is used for this purpose. The MME updates the location to
the S-GW using the User Location Information (ULI) IE.
The following S11 messages are used to transfer CRA and ULI information between the MME and S-GW:
 Create Session Request: The ULI IE is included for E-UTRAN Initial Attach and UE-requested PDN
Connectivity procedures. It includes ECGI and TAI. The MME includes the ULI IE for TAU/ X2 -Handover
procedure if the P-GW has requested location information change reporting and the MME support location
information change reporting. The S-GW includes the ULI IE on S5/S8 exchanges if it receives the ULI from
the MME. If the MME supports change reporting, it sets the corresponding indication flag in the Create
Session Request message.
 Create Session Response: The CRA IE in the Create Session Response message can be populated by the S-GW
to indicate the type of reporting required.
 Create Bearer Request: The CRA IE is included with the appropriate Action field if the Location Change
Reporting mechanism is to be started or stopped for the subscriber in the MME.
 Modify Bearer Request: The MME includes the ULI IE for TAU/Handover procedures and UE-initiated
Service Request procedures if the P-GW has requested location information change reporting and the MME
supports location information change reporting. The S-GW includes this IE on S5/S8 exchanges if it receives
the ULI from the MME.
 Modify Bearer Response: The CRA IE is included with the appropriate Action field if the Location Change
Reporting mechanism is to be started or stopped for the subscriber in the MME.
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 Delete Session Request: The MME includes the ULI IE for the Detach procedure if the P-GW has requested
location information change reporting and MME supports location information change reporting. The S-GW
includes this IE on S5/S8 exchanges if it receives the ULI from the MME.
 Update Bearer Request: The CRA IE is included with the appropriate Action field if the Location Change
Reporting mechanism is to be started or stopped for the subscriber in the MME.
 Change Notification Request: If no existing procedure is running for a UE, a Change Notification Request is
sent upon receipt of an S1-AP location report message. If an existing procedure is running, one of the
following messages reports the ULI:
 Create Session Request
 Create Bearer Response
 Modify Bearer Request
 Update Bearer Response
 Delete Bearer Response
 Delete Session Request
If an existing Change Notification Request is pending, it is aborted and a new one is sent.
Important: Information on configuring User Location Information (ULI) Reporting support is located in the
Configuring Optional Features on the MME section of the Mobility Management Entity Configuration chapter in the
Mobility Management Entity Administration Guide.
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How the Serving Gateway Works
This section provides information on the function of the S-GW in an EPC E-UTRAN network and presents call
procedure flows for different stages of session setup and disconnect.
The S-GW supports the following network flows:
 GTP Serving Gateway Call Session Procedures in an LTE-SAE Network
GTP Serving Gateway Call/Session Procedures in an LTE-SAE Network
The following topics and procedure flows are included:
 Subscriber-initiated Attach (initial)
 Subscriber-initiated Detach
Subscriber-initiated Attach (initial)
This section describes the procedure of an initial attach to the EPC network by a subscriber.
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Figure 16.
Subscriber-initiated Attach (initial) Call Flow
Table 2. Subscriber-initiated Attach (initial) Call Flow Description
Step
Description
1
The UE initiates the Attach procedure by the transmission of an Attach Request (IMSI or old GUTI, last visited TAI (if
available), UE Network Capability, PDN Address Allocation, Protocol Configuration Options, Attach Type) message
together with an indication of the Selected Network to the eNodeB. IMSI is included if the UE does not have a valid GUTI
available. If the UE has a valid GUTI, it is included.
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Step
Description
2
The eNodeB derives the MME from the GUTI and from the indicated Selected Network. If that MME is not associated
with the eNodeB, the eNodeB selects an MME using an MME selection function. The eNodeB forwards the Attach
Request message to the new MME contained in a S1-MME control message (Initial UE message) together with the
Selected Network and an indication of the E-UTRAN Area identity, a globally unique E-UTRAN ID of the cell from where
it received the message to the new MME.
3
If the UE is unknown in the MME, the MME sends an Identity Request to the UE to request the IMSI.
4
The UE responds with Identity Response (IMSI).
5
If no UE context for the UE exists anywhere in the network, authentication is mandatory. Otherwise this step is optional.
However, at least integrity checking is started and the ME Identity is retrieved from the UE at Initial Attach. The
authentication functions, if performed this step, involves AKA authentication and establishment o f a NAS level security
association with the UE in order to protect further NAS protocol messages.
6
The MME sends an Update Location (MME Identity, IMSI, ME Identity) to the HSS.
7
The HSS acknowledges the Update Location message by sending an Update Location Ack to the MME. This message also
contains the Insert Subscriber Data (IMSI, Subscription Data) Request. The Subscription Data contains the list of all APNs
that the UE is permitted to access, an indication about which of those APNs is the Default APN, and the EPS subscribed
QoS profile for each permitted APN. If the Update Location is rejected by the HSS, the MME rejects the Attach Request
from the UE with an appropriate cause.
8
The MME selects an S-GW using the Serving GW selection function and allocates an EPS Bearer Identity for the Default
Bearer associated with the UE. If the PDN subscription context contains no P-GW address the MME selects a P-GW as
described in clause PDN GW selection function. Then it sends a Create Default Bearer Request (IMSI, MME Context ID,
APN, RAT type, Default Bearer QoS, PDN Address Allocation, AMBR, EPS Bearer Identity, Protocol Configuration
Options, ME Identity, User Location Information) message to the selected S-GW.
9
The S-GW creates a new entry in its EPS Bearer table and sends a Create Default Bearer Request (IMSI, APN, S-GW
Address for the user plane, S-GW TEID of the user plane, S-GW TEID of the control plane, RAT type, Default Bearer
QoS, PDN Address Allocation, AMBR, EPS Bearer Identity, Protocol Configuration Options, ME Identity, User Location
Information) message to the P-GW.
10
If dynamic PCC is deployed, the P-GW interacts with the PCRF to get the default PCC rules for the UE. The IMSI, UE IP
address, User Location Information, RAT type, AMBR are provided to the PCRF by the P-GW if received by the previous
message.
11
The P-GW returns a Create Default Bearer Response (P-GW Address for the user plane, P-GW TEID of the user plane, PGW TEID of the control plane, PDN Address Information, EPS Bearer Identity, Protocol Configuration Options) message
to the S-GW. PDN Address Information is included if the P-GW allocated a PDN address Based on PDN Address
Allocation received in the Create Default Bearer Request. PDN Address Information contains an IPv4 address for IPv4
and/or an IPv6 prefix and an Interface Identifier for IPv6. The P-GW takes into account the UE IP version capability
indicated in the PDN Address Allocation and the policies of operator when the P-GW allocates the PDN Address
Information. Whether the IP address is negotiated by the UE after completion of the Attach procedure, this is indicated in
the Create Default Bearer Response.
12
The Downlink (DL) Data can start flowing towards S-GW. The S-GW buffers the data.
13
The S-GW returns a Create Default Bearer Response (PDN Address Information, S-GW address for User Plane, S-GW
TEID for User Plane, S-GW Context ID, EPS Bearer Identity, Protocol Configuration Options) message to the new MME.
PDN Address Information is included if it was provided by the P-GW.
14
The new MME sends an Attach Accept (APN, GUTI, PDN Address Information, TAI List, EPS Bearer Identity, Session
Management Configuration IE, Protocol Configuration Options) message to the eNodeB.
15
The eNodeB sends Radio Bearer Establishment Request including the EPS Radio Bearer Identity to the UE. The Attach
Accept message is also sent along to the UE.
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Step
Description
16
The UE sends the Radio Bearer Establishment Response to the eNodeB. In this message, the Attach Complete message
(EPS Bearer Identity) is included.
17
The eNodeB forwards the Attach Complete (EPS Bearer Identity) message to the MME.
18
The Attach is complete and UE sends data over the default bearer. At this time the UE can send uplink packets towards the
eNodeB which are then tunnelled to the S-GW and P-GW.
19
The MME sends an Update Bearer Request (eNodeB address, eNodeB TEID) message to the S-GW.
20
The S-GW acknowledges by sending Update Bearer Response (EPS Bearer Identity) message to the MME.
21
The S-GW sends its buffered downlink packets.
22
After the MME receives Update Bearer Response (EPS Bearer Identity) message, if an EPS bearer was established and the
subscription data indicates that the user is allowed to perform handover to non-3GPP accesses, and if the MME selected a
P-GW that is different from the P-GW address which was indicated by the HSS in the PDN subscription context, the MME
sends an Update Location Request including the APN and P-GW address to the HSS for mobility with non-3GPP accesses.
23
The HSS stores the APN and P-GW address pair and sends an Update Location Response to the MME.
24
Bidirectional data is passed between the UE and PDN.
Subscriber-initiated Detach
This section describes the procedure of detachment from the EPC network by a subscriber.
Figure 17.
Subscriber-initiated Detach Call Flow
Table 3. Subscriber-initiated Detach Call Flow Description
Step
Description
1
The UE sends NAS message Detach Request (GUTI, Switch Off) to the MME. Switch Off indicates whether detach is due
to a switch off situation or not.
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Step
Description
2
The active EPS Bearers in the S-GW regarding this particular UE are deactivated by the MME sending a Delete Bearer
Request (TEID) message to the S-GW.
3
The S-GW sends a Delete Bearer Request (TEID) message to the P-GW.
4
The P-GW acknowledges with a Delete Bearer Response (TEID) message.
5
The P-GW may interact with the PCRF to indicate to the PCRF that EPS Bearer is released if PCRF is applied in the
network.
6
The S-GW acknowledges with a Delete Bearer Response (TEID) message.
7
If Switch Off indicates that the detach is not due to a switch off situation, the MME sends a Detach Accept message to the
UE.
8
The MME releases the S1-MME signalling connection for the UE by sending an S1 Release command to the eNodeB with
Cause = Detach.
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How the PDN Gateway Works
This section provides information on the function of the P-GW in an EPC E-UTRAN network and presents call
procedure flows for different stages of session setup and disconnect.
The P-GW supports the following network flows:
 PMIPv6 PDN Gateway Call Session Procedures in an eHRPD Network
 GTP PDN Gateway Call Session Procedures in an LTE-SAE Network
PMIPv6 PDN Gateway Call/Session Procedures in an eHRPD Network
The following topics and procedure flows are included:
 Initial Attach with IPv6IPv4 Access
 PMIPv6 Lifetime Extension without Handover
 PDN Connection Release Initiated by UE
 PDN Connection Release Initiated by HSGW
 PDN Connection Release Initiated by P-GW
Initial Attach with IPv6/IPv4 Access
This section describes the procedure of initial attach and session establishment for a subscriber (UE).
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Figure 18.
Initial Attach with IPv6/IPv4 Access Call Flow
Table 4. Initial Attach with IPv6/IPv4 Access Call Flow Description
Step
Description
1
The subscriber (UE) attaches to the eHRPD network.
2a
The eAN/PCF sends an A11 RRQ to the HSGW. The eAN/PCF includes the true IMSI of the UE in the A11 RRQ.
2b
The HSGW establishes A10s and respond back to the eAN/PCF with an A11 RRP.
3a
The UE performs LCP negotiation with the HSGW over the established main A10.
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Step
Description
3b
The UE performs EAP over PPP.
3c
EAP authentication is completed between the UE and the 3GPP AAA. Durin g this transaction, the HSGW receives the
subscriber profile from the AAA server.
4a
After receiving the subscriber profile, the HSGW sends the QoS profile in A11 Session Update Message to the eAN/PCF.
4b
The eAN/PCF responds with an A11 Session Update Acknowledgement (SUA).
5a
The UE initiates a PDN connection by sending a PPP-VSNCP-Conf-Req message to the HSGW. The message includes the
PDNID of the PDN, APN, PDN-Type=IPv6/[IPv4], PDSN-Address and, optionally, PCO options the UE is expecting from
the network.
5b
The HSGW sends a PBU to the P-GW.
5c
The P-GW processes the PBU from the HSGW, assigns an HNP for the connection and responds back to the HSGW with
PBA.
5d
The HSGW responds to the VSNCP Conf Req with a VSNCP Conf Ack.
5e
The HSGW sends a PPP-VSNCP-Conf-Req to the UE to complete PPP VSNCP negotiation.
5f
The UE completes VSNCP negotiation by returning a PPP-VSNCP-Conf-Ack.
6
The UE optionally sends a Router Solicitation (RS) message.
7
The HSGW sends a Router Advertisement (RA) message with the assigned Prefix.
PMIPv6 Lifetime Extension without Handover
This section describes the procedure of a session registration lifetime extension by the P-GW without the occurrence of
a handover.
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Figure 19.
PMIPv6 Lifetime Extension (without handover) Call Flow
Table 5. PMIPv6 Lifetime Extension (without handover) Call Flow Description
Step
Description
1
The UE is attached to the EPC and has a PDN connection with the P-GW where PDNID=x and an APN with assigned
HNP.
2
The HSGW MAG service registration lifetime nears expiration and triggers a renewal request for the LMA.
3
The MAG service sends a Proxy Binding Update (PBU) to the P-GW LMA service with the following attributes: Lifetime,
MNID, APN, ATT=HRPD, HNP.
4
The P-GW LMA service updates the Binding Cache Entry (BCE) with the new granted lifetime.
5
The P-GW responds with a Proxy Binding Acknowledgement (PBA) with the following attributes: Lifetime, MNID, APN.
PDN Connection Release Initiated by UE
This section describes the procedure of a session release by the UE.
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Figure 20.
PDN Connection Release by the UE Call Flow
Table 6. PDN Connection Release by the UE Call Flow Description
Step
Description
1
The UE is attached to the EPC and has a PDN connection with the P-GW for PDN-ID=x and APN with assigned HNP.
2
The UE decides to disconnect from the PDN and sends a PPP VSNCP-Term-Req with PDNID=x.
3
The HSGW starts disconnecting the PDN connection and sends a PPP-VSNCP-Term-Ack to the UE (also with PDNID=x).
4
The HSGW begins the tear down of the PMIP session by sending a PBU Deregistration to the P-GW with the following
attributes: Lifetime=0, MNID, APN, ATT=HRPD, HNP. The PBU Deregistration message should contain all the mobility
options that were present in the initial PBU that created the binding.
5
The P-GW looks up the Binding Cache Entry (BCE) based on the HNP, deletes the binding, and responds to the HSGW
with a Deregistration PBA with the same attributes (Lifetime=0, MNID, APN, ATT=HRPD, HNP).
6
The HSGW optionally sends a Router Advertisement (RA) with assigned HNP and prefix lifetime=0.
PDN Connection Release Initiated by HSGW
This section describes the procedure of a session release by the HSGW.
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Figure 21.
PDN Connection Release by the HSGW Call Flow
Table 7. PDN Connection Release by the HSGW Call Flow Description
Step
Description
1
The UE is attached to the EPC and has a PDN connection with the P-GW for PDN-ID=x and APN with assigned HNP.
2
The HSGW MAG service triggers a disconnect of the PDN connection for PDNID=x.
3
The HSGW sends a PPP VSNCP-Term-Req with PDNID=x to the UE.
4
The UE acknowledges the receipt of the request with a VSNCP-Term-Ack (PDNID=x).
5
The HSGW begins the tear down of the PMIP session by sending a PBU Deregistration to the P-GW with the following
attributes: Lifetime=0, MNID, APN, HNP. The PBU Deregistration message should contain all the mobility options that
were present in the initial PBU that created the binding.
6
The P-GW looks up the BCE based on the HNP, deletes the binding, and responds to the HSGW with a Deregistration PBA
with the same attributes (Lifetime=0, MNID, APN, ATT=HRPD, HNP).
7
The HSGW optionally sends a Router Advertisement (RA) with assigned HNP and prefix lifetime=0.
PDN Connection Release Initiated by P-GW
This section describes the procedure of a session release by the P-GW.
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Figure 22.
PDN Connection Release by the P-GW Call Flow
Table 8. PDN Connection Release by the P-GW Call Flow Description
Step
Description
1
The UE is attached to the EPC and has a PDN connection with the P-GW for PDN-ID=x and APN with assigned HNP.
2
A PGW trigger causes a disconnect of the PDN connection for PDNID=x and the PGW sends a Binding Revocation
Indication (BRI) message to the HSGW with the following attributes: MNID, APN, HNP.
3
The HSGW responds to the BRI message with a Binding Revocation Acknowledgement (BRA) message with the sane
attributes (MNID, APN, HNP).
4
The HSGW MAG service triggers a disconnect of the UE PDN connection for PDNID=x.
5
The HSGW sends a PPP VSNCP-Term-Req with PDNID=x to the UE.
6
The UE acknowledges the receipt of the request with a VSNCP-Term-Ack (PDNID=x).
7
The HSGW optionally sends a Router Advertisement (RA) with assigned HNP and prefix lifetime=0.
GTP PDN Gateway Call/Session Procedures in an LTE-SAE Network
The following topics and procedure flows are included:
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 Subscriber-initiated Attach (initial)
 Subscriber-initiated Detach
Subscriber-initiated Attach (initial)
This section describes the procedure of an initial attach to the EPC network by a subscriber.
Figure 23.
Subscriber-initiated Attach (initial) Call Flow
Table 9. Subscriber-initiated Attach (initial) Call Flow Description
Step
Description
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Step
Description
1
The UE initiates the Attach procedure by the transmission of an Attach Request (IMSI or old GUTI, last visited TAI (if
available), UE Network Capability, PDN Address Allocation, Protocol Configuration Options, Attach Type) message
together with an indication of the Selected Network to the eNodeB. IMSI is included if the UE does not have a valid GUTI
available. If the UE has a valid GUTI, it is included.
2
The eNodeB derives the MME from the GUTI and from the indicated Selected Network. If that MME is not associated
with the eNodeB, the eNodeB selects an MME using an “MME selection function”. The eNodeB forwards the Attach
Request message to the new MME contained in a S1-MME control message (Initial UE message) together with the
Selected Network and an indication of the E-UTRAN Area identity, a globally unique E-UTRAN ID of the cell from where
it received the message to the new MME.
3
If the UE is unknown in the MME, the MME sends an Identity Request to the UE to request the IMSI.
4
The UE responds with Identity Response (IMSI).
5
If no UE context for the UE exists anywhere in the network, authentication is mandatory. Otherwise this step is optional.
However, at least integrity checking is started and the ME Identity is retrieved from the UE at Initial Attach. The
authentication functions, if performed this step, involves AKA authentication and establishment of a NAS level security
association with the UE in order to protect further NAS protocol messages.
6
The MME sends an Update Location (MME Identity, IMSI, ME Identity) to the HSS.
7
The HSS acknowledges the Update Location message by sending an Update Location Ack to the MME. This message also
contains the Insert Subscriber Data (IMSI, Subscription Data) Request. The Subscription Data contains the list of all APNs
that the UE is permitted to access, an indication about which of those APNs is the Default APN, and the 'EPS subscribed
QoS profile' for each permitted APN. If the Update Location is rejected by the HSS, the MME rejects the Attach Request
from the UE with an appropriate cause.
8
The MME selects an S-GW using “Serving GW selection function” and allocates an EPS Bearer Identity for the Default
Bearer associated with the UE. If the PDN subscription context contains no P-GW address the MME selects a P-GW as
described in clause “PDN GW selection function”. Then it sends a Create Default Bearer Request (IMSI, MME Context ID,
APN, RAT type, Default Bearer QoS, PDN Address Allocation, AMBR, EPS Bearer Identity, Protocol Configuration
Options, ME Identity, User Location Information) message to the selected S-GW.
9
The S-GW creates a new entry in its EPS Bearer table and sends a Create Default Bearer Request (IMSI, APN, S-GW
Address for the user plane, S-GW TEID of the user plane, S-GW TEID of the control plane, RAT type, Default Bearer
QoS, PDN Address Allocation, AMBR, EPS Bearer Identity, Protocol Configuration Options, ME Identity, User Location
Information) message to the P-GW.
10
If dynamic PCC is deployed, the P-GW interacts with the PCRF to get the default PCC rules for the UE. The IMSI, UE IP
address, User Location Information, RAT type, AMBR are provided to the PCRF by the P-GW if received by the previous
message.
11
The P-GW returns a Create Default Bearer Response (P-GW Address for the user plane, P-GW TEID of the user plane, PGW TEID of the control plane, PDN Address Information, EPS Bearer Identity, Protocol Configuration Options) message
to the S-GW. PDN Address Information is included if the P-GW allocated a PDN address Based on PDN Address
Allocation received in the Create Default Bearer Request. PDN Address Information contains an IPv4 address for IPv4
and/or an IPv6 prefix and an Interface Identifier for IPv6. The P-GW takes into account the UE IP version capability
indicated in the PDN Address Allocation and the policies of operator when the P-GW allocates the PDN Address
Information. Whether the IP address is negotiated by the UE after completion of the Attach procedure, this is indicated in
the Create Default Bearer Response.
12
The Downlink (DL) Data can start flowing towards S-GW. The S-GW buffers the data.
13
The S-GW returns a Create Default Bearer Response (PDN Address Information, S-GW address for User Plane, S-GW
TEID for User Plane, S-GW Context ID, EPS Bearer Identity, Protocol Configuration Options) message to the new MME.
PDN Address Information is included if it was provided by the P-GW.
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Step
Description
14
The new MME sends an Attach Accept (APN, GUTI, PDN Address Information, TAI List, EPS Bearer Identity, Session
Management Configuration IE, Protocol Configuration Options) message to the eNodeB.
15
The eNodeB sends Radio Bearer Establishment Request including the EPS Radio Bearer Identity to the UE. The Attach
Accept message is also sent along to the UE.
16
The UE sends the Radio Bearer Establishment Response to the eNodeB. In this message, the Attach Complete message
(EPS Bearer Identity) is included.
17
The eNodeB forwards the Attach Complete (EPS Bearer Identity) message to the MME.
18
The Attach is complete and UE sends data over the default bearer. At this time the UE can send uplink packets towards the
eNodeB which are then tunnelled to the S-GW and P-GW.
19
The MME sends an Update Bearer Request (eNodeB address, eNodeB TEID) message to the S-GW.
20
The S-GW acknowledges by sending Update Bearer Response (EPS Bearer Identity) message to the MME.
21
The S-GW sends its buffered downlink packets.
22
After the MME receives Update Bearer Response (EPS Bearer Identity) message, if an EPS bearer was established and the
subscription data indicates that the user is allowed to perform handover to non-3GPP accesses, and if the MME selected a
P-GW that is different from the P-GW address which was indicated by the HSS in the PDN subscription context, the MME
sends an Update Location Request including the APN and P-GW address to the HSS for mobility with non-3GPP accesses.
23
The HSS stores the APN and P-GW address pair and sends an Update Location Response to the MME.
24
Bidirectional data is passed between the UE and PDN.
Subscriber-initiated Detach
This section describes the procedure of detachment from the EPC network by a subscriber.
Figure 24.
Subscriber-initiated Detach Call Flow
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Table 10.
Subscriber-initiated Detach Call Flow Description
Step
Description
1
The UE sends NAS message Detach Request (GUTI, Switch Off) to the MME. Switch Off indicates whether detach is due
to a switch off situation or not.
2
The active EPS Bearers in the S-GW regarding this particular UE are deactivated by the MME sending a Delete Bearer
Request (TEID) message to the S-GW.
3
The S-GW sends a Delete Bearer Request (TEID) message to the P-GW.
4
The P-GW acknowledges with a Delete Bearer Response (TEID) message.
5
The P-GW may interact with the PCRF to indicate to the PCRF that EPS Bearer is released if PCRF is applied in the
network.
6
The S-GW acknowledges with a Delete Bearer Response (TEID) message.
7
If Switch Off indicates that the detach is not due to a switch off situation, the MME sends a Detach Accept message to the
UE.
8
The MME releases the S1-MME signalling connection for the UE by sending an S1 Release command to the eNodeB with
Cause = Detach.
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S-GW Supported Standards
The S-GW service complies with the following standards.
 3GPP References
 3GPP2 References
 IETF References
 Object Management Group (OMG) Standards
3GPP References
Release 10 Supported Standards
 3GPP TS 23.007: Restoration procedures
 3GPP TS 23.060. General Packet Radio Service (GPRS); Service description; Stage 2
 3GPP TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio
Access Network (E-UTRAN) access
 3GPP TS 29.274: 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service (GPRS)
Tunnelling Protocol for Control plane (GTPv2-C); Stage 3
 3GPP TS 29.281: General Packet Radio System (GPRS) Tunnelling Protocol User Plane (GTPv1-U)
Release 9 Supported Standards
 3GPP TS 23.007: Restoration procedures
 3GPP TS 23.060. General Packet Radio Service (GPRS); Service description; Stage 2
 3GPP TS 23.216: Single Radio Voice Call Continuity (SRVCC); Stage 2 (Release 9)
 3GPP TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio
Access Network (E-UTRAN) access
 3GPP TS 29.274: 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service (GPRS)
Tunnelling Protocol for Control plane (GTPv2-C); Stage 3 (Release 9)
 3GPP TS 29.281: General Packet Radio System (GPRS) Tunnelling Protocol User Plane (GTPv1-U)
 3GPP TS 33.106: 3G Security; Lawful Interception Requirements
 3GPP TS 36.414: Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 data transport
Release 8 Supported Standards
 3GPP TR 21.905: Vocabulary for 3GPP Specifications
 3GPP TS 23.003: Numbering, addressing and identification
 3GPP TS 23.007: Restoration procedures
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 3GPP TS 23.107: Quality of Service (QoS) concept and architecture
 3GPP TS 23.203: Policy and charging control architecture
 3GPP TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio
Access Network (E-UTRAN) access
 3GPP TS 23.402: Architecture Enhancements for non-3GPP accesses
 3GPP TS 23.060. General Packet Radio Service (GPRS); Service description; Stage 2
 3GPP TS 24.008: Mobile radio interface Layer 3 specification; Core network protocols
 3GPP TS 24.229: IP Multimedia Call Control Protocol based on SIP and SDP; Stage 3
 3GPP TS 29.210. Gx application
 3GPP TS 29.212: Policy and Charging Control over Gx reference point
 3GPP TS 29.213: Policy and Charging Control signaling flows and QoS
 3GPP TS 29.214: Policy and Charging Control over Rx reference point
 3GPP TS 29.274 V8.1.1 (2009-03): 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service
(GPRS) Tunnelling Protocol for Control plane (GTPv2-C); Stage 3 (Release 8)
 3GPP TS 29.274: Evolved GPRS Tunnelling Protocol for Control plane (GTPv2-C), version 8.2.0 (both versions
are intentional)
 3GPP TS 29.275: Proxy Mobile IPv6 (PMIPv6) based Mobility and Tunnelling protocols, version 8.1.0
 3GPP TS 29.281: GPRS Tunnelling Protocol User Plane (GTPv1-U)
 3GPP TS 32.251: Telecommunication management; Charging management; Packet Switched (PS) domain
charging
 3GPP TS 32.295: Charging management; Charging Data Record (CDR) transfer
 3GPP TS 32.298: Telecommunication management; Charging management; Charging Data Record (CDR)
encoding rules description
 3GPP TS 32.299: Charging management; Diameter charging applications
 3GPP TS 33.106: 3G Security; Lawful Interception Requirements
 3GPP TS 36.107: 3G security; Lawful interception architecture and functions
 3GPP TS 36.300: Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial
Radio Access Network (E-UTRAN); Overall description
 3GPP TS 36.412. EUTRAN S1 signaling transport
 3GPP TS 36.413: Evolved Universal Terrestrial Radio Access (E-UTRA); S1 Application Protocol (S1AP)
 3GPP TS 36.414: Evolved Universal Terrestrial Radio Access Network (E-UTRAN); S1 data transport
3GPP2 References
 X.P0057-0 v0.11.0 E-UTRAN - eHRPD Connectivity and Interworking: Core Network Aspects
IETF References
 RFC 768: User Datagram Protocol (STD 6).
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 RFC 791: Internet Protocol (STD 5).
 RFC 2131: Dynamic Host Configuration Protocol
 RFC 2460: Internet Protocol, Version 6 (IPv6) Specification
 RFC 2698: A Two Rate Three Color Marker
 RFC 2784: Generic Routing Encapsulation (GRE)
 RFC 2890: Key and Sequence Number Extensions to GRE
 RFC 3319: Dynamic Host Configuration Protocol (DHCPv6) Options for Session Initiation Protocol (SIP)
Servers
 RFC 3588: Diameter Base Protocol
 RFC 3775: Mobility Support in IPv6
 RFC 3646: DNS Configuration options for Dynamic Host Configuration Protocol for IPv6 (DHCPv6)
 RFC 4006: Diameter Credit-Control Application
 RFC 4282: The Network Access Identifier
 RFC 4283: Mobile Node Identifier Option for Mobile IPv6 (MIPv6)
 RFC 4861: Neighbor Discovery for IP Version 6 (IPv6)
 RFC 4862: IPv6 Stateless Address Autoconfiguration
 RFC 5094: Mobile IPv6 Vendor Specific Option
 RFC 5213: Proxy Mobile IPv6
 Internet-Draft: Proxy Mobile IPv6
 Internet-Draft: GRE Key Option for Proxy Mobile IPv6, work in progress
 Internet-Draft: Binding Revocation for IPv6 Mobility, work in progress
Object Management Group (OMG) Standards
 CORBA 2.6 Specification 01-09-35, Object Management Group
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P-GW Supported Standards
The P-GW service complies with the following standards.
 Release 11 3GPP References
 Release 10 3GPP References
 Release 9 3GPP References
 Release 8 3GPP References
 3GPP2 References
 IETF References
 Object Management Group (OMG) Standards
Release 11 3GPP References
 3GPP TS 29.274: 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service (GPRS)
Tunnelling Protocol for Control plane (GTPv2-C)
Release 10 3GPP References
Important: The P-GW currently supports the following Release 10 3GPP specifications. Most 3GPP
specifications are also used for 3GPP2 support; any specifications that are unique to 3GPP2 are listed under 3GPP2
References.
 3GPP TS 23.007: Restoration procedures
 3GPP TS 23.203: Policy and charging control architecture; Stage 2
 3GPP TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio
Access Network (E-UTRAN) access
 3GPP TS 23.402: Architecture enhancements for non-3GPP accesses
 3GPP TS 29.212: Policy and Charging Control over Gx reference point
 3GPP TS 29.274: 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service (GPRS)
Tunnelling Protocol for Control plane (GTPv2-C)
 3GPP TS 29.281: GPRS Tunnelling Protocol User Plane (GTPv1-U)
Release 9 3GPP References
Important: The P-GW currently supports the following Release 9 3GPP specifications. Most 3GPP
specifications are also used for 3GPP2 support; any specifications that are unique to 3GPP2 are listed under 3GPP2
References.
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 3GPP TR 21.905: Vocabulary for 3GPP Specifications
 3GPP TS 22.115: Service aspects; Charging and billing
 3GPP TS 23.003: Numbering, addressing and identification
 3GPP TS 23.007: Restoration procedures
 3GPP TS 23.060. General Packet Radio Service (GPRS); Service description; Stage 2
 3GPP TS 23.203: Policy and charging control architecture
 3GPP TS 23.207: End-to-end Quality of Service (QoS) concept and architecture
 3GPP TS 23.216: Single Radio Voice Call Continuity (SRVCC); Stage 2
 3GPP TS 23.228: IP Multimedia Subsystem (IMS); Stage 2
 3GPP TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio
Access Network (E-UTRAN) access
 3GPP TS 23.402. Architecture enhancements for non-3GPP accesses
 3GPP TS 24.008: Mobile radio interface Layer 3 specification; Core network protocols
 3GPP TS 29.060: General Packet Radio Service (GPRS); GPRS Tunnelling Protocol (GTP) across the Gn and
Gp interface
 3GPP TS 29.061: Interworking between the Public Land Mobile Network (PLMN) supporting packet based
services and Packet Data Networks (PDN)
 3GPP TS 29.212: Policy and Charging Control over Gx reference point
 3GPP TS 29.214: Policy and Charging control over Rx reference point
 3GPP TS 29.229: Cx and Dx interfaces based on Diameter protocol
 3GPP TS 29.230: Diameter applications; 3GPP specific codes and identifiers
 3GPP TS 29.272: Evolved Packet System (EPS); Mobility Management Entity (MME) and Serving GPRS
Support Node (SGSN) related interfaces based on Diameter protocol
 3GPP TS 29.273: 3GPP EPS AAA Interfaces
 3GPP TS 29.274: 3GPP Evolved Packet System (EPS); Evolved General Packet Radio Service (GPRS)
Tunnelling Protocol for Control plane (GTPv2-C); Stage 3
 3GPP TS 29.275: Proxy Mobile IPv6 (PMIPv6) based Mobility and Tunnelling protocols; Stage 3
 3GPP TS 29.281: General Packet Radio System (GPRS) Tunnelling Protocol User Plane (GTPv1-U)
 3GPP TS 29.282: Mobile IPv6 vendor specific option format and usage within 3GPP
 3GPP TS 32.240: Telecommunication management; Charging management; Charging architecture and principles
 3GPP TS 32.251: Telecommunication management; Charging management; Packet Switched (PS) domain
charging
 3GPP TS 32.298: Telecommunication management; Charging management; Charging Data Record (CDR)
parameter description
 3GPP TS 32.299: Telecommunication management; Charging management; Diameter charging appl ication
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Release 8 3GPP References
Important: The P-GW currently supports the following Release 8 3GPP specifications. Most 3GPP
specifications are also used for 3GPP2 support; any specifications that are unique to 3GPP2 are listed under 3GPP2
References.
 3GPP TR 21.905: Vocabulary for 3GPP Specifications
 3GPP TS 23.003: Numbering, addressing and identification
 3GPP TS 23.007: Restoration procedures
 3GPP TS 23.060. General Packet Radio Service (GPRS); Service description; Stage 2
 3GPP TS 23.107: Quality of Service (QoS) concept and architecture
 3GPP TS 23.203: Policy and charging control architecture
 3GPP TS 23.401: General Packet Radio Service (GPRS) enhancements for Evolved Universal Terrestrial Radio
Access Network (E-UTRAN) access
 3GPP TS 23.402. Architecture enhancements for non-3GPP accesses
 3GPP TS 23.869: Support for Internet Protocol (IP) based IP Multimedia Subsystem (IMS) Emergency calls
over General Packet Radio Service (GPRS) and Evolved Packet Service (EPS)
 3GPP TS 24.008: Mobile radio interface Layer 3 specification; Core network protocols
 3GPP TS 24.229: IP Multimedia Call Control Protocol based on SIP and SDP; Stage 3
 3GPP TS 27.060: Mobile Station (MS) supporting Packet Switched Services
 3GPP TS 29.061: Interworking between the Public Land Mobile Network (PLMN) supporting packet based
services and Packet Data Networks (PDN)
 3GPP TS 29.210. Charging rule provisioning over Gx interface
 3GPP TS 29.212: Policy and Charging Control over Gx reference point
 3GPP TS 29.213: Policy and Charging Control signaling flows and QoS
 3GPP TS 29.273: 3GPP EPS AAA Interfaces
 3GPP TS 29.274: Evolved GPRS Tunnelling Protocol for Control plane (GTPv2-C)
 3GPP TS 29.275: Proxy Mobile IPv6 (PMIPv6) based Mobility and Tunnelling protocols
 3GPP TS 29.281: GPRS Tunnelling Protocol User Plane (GTPv1-U)
 3GPP TS 29.282: Mobile IPv6 vendor specific option format and usage within 3GPP
 3GPP TS 32.295: Charging management; Charging Data Record (CDR) transfer
 3GPP TS 32.298: Telecommunication management; Charging management; Charging Data Record (CDR)
encoding rules description
 3GPP TS 32.299: Charging management; Diameter charging applications
 3GPP TS 36.300. EUTRA and EUTRAN; Overall description Stage 2
 3GPP TS 36.412. EUTRAN S1 signaling transport
 3GPP TS 36.413. EUTRAN S1 Application Protocol (S1AP)
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3GPP2 References
 X.S0057-0 v3.0 E-UTRAN - eHRPD Connectivity and Interworking: Core Network Aspects
IETF References
 RFC 768: User Datagram Protocol (STD 6).
 RFC 791: Internet Protocol (STD 5).
 RFC 1701, Generic Routing Encapsulation (GRE)
 RFC 1702, Generic Routing Encapsulation over IPv4 networks
 RFC 2131: Dynamic Host Configuration Protocol
 RFC 2460: Internet Protocol, Version 6 (IPv6) Specification
 RFC 2473: Generic Packet Tunneling in IPv6 Specification
 RFC 2698: A Two Rate Three Color Marker
 RFC 2784: Generic Routing Encapsulation (GRE)
 RFC 2890: Key and Sequence Number Extensions to GRE
 RFC 3162: RADIUS and IPv6
 RFC 3266: Support for IPv6 in Session Description Protocol (SDP)
 RFC 3319: Dynamic Host Configuration Protocol (DHCPv6) Options for Session Initiation Protocol (SIP)
Servers
 RFC 3588: Diameter Base Protocol
 RFC 3589: Diameter Command Codes for Third Generation Partnership Project (3GPP) Release 5
 RFC 3646: DNS Configuration options for Dynamic Host Configuration Protocol for IPv6 (DHCPv6)
 RFC 3775: Mobility Support in IPv6
 RFC 4004: Diameter Mobile IPv4 Application
 RFC 4005: Diameter Network Access Server Application
 RFC 4006: Diameter Credit-Control Application
 RFC 4282: The Network Access Identifier
 RFC 4283: Mobile Node Identifier Option for Mobile IPv6 (MIPv6)
 RFC 4861: Neighbor Discovery for IP Version 6 (IPv6)
 RFC 4862: IPv6 Stateless Address Autoconfiguration
 RFC 5094: Mobile IPv6 Vendor Specific Option
 RFC 5149: Service Selection for Mobile IPv6
 RFC 5213: Proxy Mobile IPv6
 RFC 5447: Diameter Mobile IPv6: Support for NAS to Diameter Server Interaction
 RFC 5555: Mobile IPv6 Support for Dual Stack Hosts and Routers
 RFC 5844: IPv4 Support for Proxy Mobile IPv6
 RFC 5845: Generic Routing Encapsulation (GRE) Key Option for Proxy Mobile IPv6
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 RFC 5846: Binding Revocation for IPv6 Mobility
 Internet-Draft (draft-ietf-dime-qos-attributes-07): QoS Attributes for Diameter
 Internet-Draft (draft-ietf-mip6-nemo-v4traversal-06.txt): Mobile IPv6 support for dual stack Hosts and Routers
(DSMIPv6)
 Internet-Draft (draft-ietf-netlmm-grekey-option-01.txt): GRE Key Option for Proxy Mobile IPv6, work in
progress
 Internet-Draft (draft-ietf-netlmm-pmip6-ipv4-support-02.txt) IPv4 Support for Proxy Mobile IPv6
 Internet-Draft (draft-ietf-netlmm-proxymip6-07.txt): Proxy Mobile IPv6
 Internet-Draft (draft-ietf-mext-binding-revocation-02.txt): Binding Revocation for IPv6 Mobility, work in
progress
 Internet-Draft (draft-meghana-netlmm-pmipv6-mipv4-00.txt) Proxy Mobile IPv6 and Mobile IPv4 interworking
Object Management Group (OMG) Standards
 CORBA 2.6 Specification 01-09-35, Object Management Group
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SAE Gateway Configuration
This chapter provides configuration information for the SAE Gateway (SAEGW).
Important: Information about all commands in this chapter can be found in the Command Line Interface
Reference.
Because each wireless network is unique, the system is designed with a variety of parameters allowing it to perform in
various wireless network environments. In this chapter, only the minimum set of parameters are provided to make the
system operational. Optional configuration commands specific to the SAEGW product are located in the Command Line
Interface Reference.
The following procedures are located in this chapter:
 Configuring an SAEGW Service
 Configuring an eGTP S-GW Service
 Configuring Optional Features on the eGTP S-GW
 Configuring an eGTP P-GW Service
 Configuring Optional Features on the P-GW
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Configuring an SAEGW Service
This section provides a high-level series of steps and the associated configuration file examples for configuring the
system to perform as an SAEGW in a test environment. Information provided in this section includes the following:
 Information Required
 SAEGW Configuration
Information Required
The following sections describe the minimum amount of information required to configure and make the SAEGW
operational on the network. To make the process more efficient, it is recommended that this information be available
prior to configuring the system.
There are additional configuration parameters that are not described in this section. These parameters deal mostly with
fine-tuning the operation of the SAEGW in the network. Information on these parameters can be found in the
appropriate sections of the Command Line Interface Reference.
Required Local Context Configuration Information
The following table lists the information that is required to configure the local context on an SAEGW.
Table 11.
Required
Information
Required Information for Local Context Configuration
Description
Management Interface Configuration
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface will be
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and
subnet
IPv4 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number
where the line card resides followed by the number of the physical connector on the card. For example, port
17/1 identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP address
Used when configuring static IP routes from the management interface(s) to a specific network.
Security
administrator name
The name or names of the security administrator with full rights to the system.
Security
administrator
password
Open or encrypted passwords can be used.
Remote access
type(s)
The type of remote access that will be used to access the system such as telnetd, sshd, and/or ftpd.
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Required SAEGW Context Configuration Information
The following table lists the information that is required to configure the SAEGW context on an SAEGW.
Table 12.
Required Information for SAEGW Context Configuration
Required
Information
Description
SAEGW context
name
An identification string from 1 to 79 characters (alpha and/or numeric) by which the SAEGW context will
be recognized by the system.
SAEGW Service Configuration
SAEGW service
name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the SAEGW service will
be recognized by the system.
S-GW service name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the S-GW service will be
recognized by the system.
P-GW service name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the P-GW service will be
recognized by the system.
SAEGW Configuration
Step 1
Set system configuration parameters such as activating PSCs by applying the example configurations found in the
System Administration Guide.
Step 2
Set initial configuration parameters such as creating contexts and services by applying the example configurations
found in the Initial Configuration section of this section.
Step 3
Configure the system to perform as an SAEGW and associate an eGTP S-GW service and eGTP P-GW service by
applying the example configurations presented in the SAEGW Service Configuration section.
Step 4
Verify and save the configuration by following the steps found in the Verifying and Saving the Configuration section.
Initial Configuration
Step 1
Set local system management parameters by applying the example configuration in the Modifying the Local Context
section.
Step 2
Create the context where the SAEGW, S-GW, and P-GW services will reside by applying the example configuration in
the Creating andConfiguring an SAEGW Context section.
Step 3
Configure an eGTP S-GW service by applying the example configurations found in the Configuring an eGTP S-GW
Service section of this chapter.
Step 4
Configure an eGTP P-GW service by applying the example configurations found in the Configuring an eGTP P-GW
Service section of this chapter.
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Modifying the Local Context
Use the following example to set the default subscriber and configure remote access capability in the local context:
configure
context local
interface <lcl_cntxt_intrfc_name>
ip address <ip_address> <ip_mask>
exit
server ftpd
exit
server telnetd
exit
subscriber default
exit
administrator <name> encrypted password <password> ftp
ip route <ip_addr/ip_mask> <next_hop_addr> <lcl_cntxt_intrfc_name>
exit
port ethernet <slot#/port#>
no shutdown
bind interface <lcl_cntxt_intrfc_name> local
end
Creating andConfiguring an SAEGW Context
Use the following example to create the context where the SAEGW, S-GW, and P-GW services will reside:
configure
context <saegw_context_name>
end
SAEGW Service Configuration
Step 1
Configure the SAEGW service by applying the example configuration in the Configuring the SAEGW Service section.
Configuring the SAEGW Service
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Use the following example to configure the SAEGW service:
configure
context <saegw_context_name>
saegw-service <saegw_service_name> -noconfirm
associate sgw-service <sgw_service_name>
associate pgw-service <pgw_service_name>
end
Notes:
 The SAEGW, S-GW, and P-GW services must all reside within the same SAEGW context.
Verifying and Saving the Configuration
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
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Configuring an eGTP S-GW Service
This section provides a high-level series of steps and the associated configuration file examples for configuring the
system to perform as an eGTP S-GW in a test environment. Information provided in this section includes the following:
 Information Required
 How This Configuration Works
 eGTP S-GW Configuration
Information Required
The following sections describe the minimum amount of information required to configure and make the S-GW
operational on the network. To make the process more efficient, you should have this information available prior to
configuring the system.
There are additional configuration parameters that are not described in this section. These parameters deal mostly with
fine-tuning the operation of the S-GW in the network. Information on these parameters can be found in the appropriate
sections of the Command Line Interface Reference.
Required S-GW Ingress Context Configuration Information
The following table lists the information that is required to configure the S-GW ingress context on an eGTP S-GW.
Table 13.
Required Information for S-GW Ingress Context Configuration
Required Information
Description
S-GW ingress context
name
An identification string from 1 to 79 characters (alpha and/or numeric) by which the S-GW ingress
context is recognized by the system.
Accounting policy
name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the accounting policy
is recognized by the system. The accounting policy is used to set parameters for the Rf (off-line
charging) interface.
S1-U/S11 Interface Configuration (To/from eNodeB/MME)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and subnet
IPv4 or IPv6 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number
where the line card resides followed by the number of the physical connector on the card. For example,
port 17/1 identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP address
Used when configuring static IP routes from the interface(s) to a specific network.
Gateway IP address
Used when configuring static IP routes from the interface(s) to a specific network.
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Required Information
Description
GTP-U Service Configuration
GTP-U service name
(for S1-U/S11
interface)
An identification string from 1 to 63 characters (alpha and/or numeric) by which the GTP-U service
bound to the S1-U/S11 interface will be recognized by the system.
IP address
S1-U/S11 interface IPv4 or IPv6 address.
S-GW Service Configuration
S-GW service name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the S-GW service is
recognized by the system.
Multiple names are needed if multiple S-GW services will be used.
eGTP Ingress Service Configuration
eGTP S1-U/S11
ingress service name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the eGTP S1 -U/S11
ingress service is recognized by the system.
Required S-GW Egress Context Configuration Information
The following table lists the information that is required to configure the S-GW egress context on an eGTP S-GW.
Table 14.
Required Information for S-GW Egress Context Configuration
Required Information
Description
S-GW egress context
name
An identification string from 1 to 79 characters (alpha and/or numeric) by which the S-GW egress
context is recognized by the system.
S5/S8 Interface Configuration (To/from P-GW)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and subnet
IPv4 or IPv6 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number
where the line card resides followed by the number of the physical connector on the card. For example,
port 17/1 identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP address
Used when configuring static IP routes from the interface(s) to a specific network.
GTP-U Service Configuration
GTP-U service name
(for S5/S8 interface)
An identification string from 1 to 63 characters (alpha and/or numeric) by which the GTP-U service
bound to the S5/S8 interface will be recognized by the system.
IP address
S5/S8 interface IPv4 or IPv6 address.
eGTP Egress Service Configuration
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Required Information
Description
eGTP Egress Service
Name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the eGTP egress service
is recognized by the system.
How This Configuration Works
The following figure and supporting text describe how this configuration with a single ingress and egress context is used
by the system to process a subscriber call.
Figure 25.
eGTP S-GW Call Processing Using a Single Ingress and Egress Context
1. A subscriber session from the MME is received by the S-GW service over the S11 interface.
2. The S-GW service determines which context to use to access PDN services for the session. This process is
described in the How the System Selects Contexts section located in the Understanding the System Operation
and Configuration chapter of the System Administration Guide.
3. S-GW uses the configured egress context to determine the eGTP service to use for the outgoing S5/S8
connection.
4. The S-GW establishes the S5/S8 connection by sending a create session request message to the P-GW.
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5. The P-GW responds with a Create Session Response message that includes the PGW S5/S8 Address for control
plane and bearer information.
6. The S-GW conveys the control plane and bearer information to the MME in a Create Session Response message.
7. The MME responds with a Create Bearer Response and Modify Bearer Request message.
8. The S-GW sends a Modify Bearer Response message to the MME.
eGTP S-GW Configuration
To configure the system to perform as an eGTP S-GW, review the following graphic and subsequent steps.
Figure 26.
eGTP S-GW Configurable Components
Step 1
Set system configuration parameters such as activating PSCs by applying the example configurations found in the
System Administration Guide.
Step 2
Set initial configuration parameters such as creating contexts and services by applying the example configurations
found in the Initial Configuration section of this section.
Step 3
Configure the system to perform as an eGTP S-GW and set basic S-GW parameters such as eGTP interfaces and an IP
route by applying the example configurations presented in the eGTP Configuration section.
Step 4
Verify and save the configuration by following the instruction in the Verifying and Saving the Configuration section.
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Initial Configuration
Step 1
Create an ingress context where the S-GW and eGTP ingress service will reside by applying the example configuration
in the Creating an S-GW Ingress Context section.
Step 2
Create an eGTP ingress service within the newly created ingress context by applying the example configuration in the
Creating an eGTP Ingress Service section.
Step 3
Create an S-GW egress context where the eGTP egress services will reside by applying the example configuration in the
Creating an S-GW Egress Context section.
Step 4
Create an eGTP egress service within the newly created egress context by applying the example configuration in the
Creating an eGTP Egress Service section.
Step 5
Create a S-GW service within the newly created ingress context by applying the example configuration in the Creating
an S-GW Service section.
Creating an S-GW Ingress Context
Use the following example to create an S-GW ingress context and Ethernet interfaces to an MME and eNodeB, and bind
the interfaces to configured Ethernet ports.
configure
context <saegw_context_name> -noconfirm
subscriber default
exit
interface <s1u-s11_interface_name>
ip address <ipv4_address_primary>
ip address <ipv4_address_secondary>
exit
ip route 0.0.0.0 0.0.0.0 <next_hop_address> <sgw_interface_name>
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <s1u-s11_interface_name> <saegw_context_name>
end
Notes:
 This example presents the S1-U/S11 connections as a shared interface. These interfaces can be separated to
support a different network architecture.
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 The S1-U/S11 interface IP address(es) can also be specified as IPv6 addresses using the ipv6 address
command.
Creating an eGTP Ingress Service
Use the following configuration example to create an eGTP ingress service:
configure
context <saegw_context_name>
egtp-service <egtp_ingress_service_name> -noconfirm
end
Creating an S-GW Egress Context
Use the following example to create an S-GW egress context and Ethernet interface to a P-GW and bind the interface to
configured Ethernet ports.
configure
context <egress_context_name> -noconfirm
interface <s5s8_interface_name> tunnel
ipv6 address <address>
tunnel-mode ipv6ip
source interface <name>
destination address <ipv4 or ipv6 address>
end
configure
port ethernet <slot_number/port_number>
no shutdown
bind interface <s5s8_interface_name> <egress_context_name>
end
Notes:
 The S5/S8 interface IP address can also be specified as an IPv4 address using the ip address command.
Creating an eGTP Egress Service
Use the following configuration example to create an eGTP egress service in the S-GW egress context:
configure
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context <egress_context_name>
egtp-service <egtp_egress_service_name> -noconfirm
end
Creating an S-GW Service
Use the following configuration example to create the S-GW service in the ingress context:
configure
context <saegw_context_name>
sgw-service <sgw_service_name> -noconfirm
end
eGTP Configuration
Step 1
Set the system’s role as an eGTP S-GW and configure eGTP service settings by applying the example configuration in
the Setting the Systems Role as an eGTP S-GW and Configuring GTP-U and eGTP Service Settings section.
Step 2
Configure the S-GW service by applying the example configuration in the Configuring the S-GW Service section.
Step 3
Specify an IP route to the eGTP Serving Gateway by applying the example configuration in the Configuring an IP
Route section.
Setting the System’s Role as an eGTP S-GW and Configuring GTP-U and eGTP Service Settings
Use the following configuration example to set the system to perform as an eGTP S-GW and configure the GTP-U and
eGTP services:
configure
context <saegw_context_name>
gtpp group default
exit
gtpu-service <gtpu_ingress_service_name>
bind ipv4-address <s1-u_s11_interface_ip_address>
exit
egtp-service <egtp_ingress_service_name>
interface-type interface-sgw-ingress
validation-mode default
associate gtpu-service <gtpu_ingress_service_name>
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gtpc bind address <s1u-s11_interface_ip_address>
exit
exit
context <sgw_egress_context_name>
gtpu-service <gtpu_egress_service_name>
bind ipv4-address <s5s8_interface_ip_address>
exit
egtp-service <egtp_egress_service_name>
interface-type interface-sgw-egress
validation-mode default
associate gtpu-service <gtpu_egress_service_name>
gtpc bind address <s5s8_interface_ip_address>
end
Notes:
 The bind command in the GTP-U ingress and egress service configuration can also be specified as an IPv6
address using the ipv6-address command.
Configuring the S-GW Service
Use the following example to configure the S-GW service:
configure
context <saegw_context_name>
sgw-service <sgw_service_name> -noconfirm
associate ingress egtp-service <egtp_ingress_service_name>
associate egress-proto gtp egress-context <egress_context_name>
qci-qos-mapping <map_name>
end
Configuring an IP Route
Use the following example to configure an IP Route for control and user plane data communication with an eGTP PDN
Gateway:
configure
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context <egress_context_name>
ip route <pgw_ip_addr/mask> <sgw_next_hop_addr> <sgw_intrfc_name>
end
Verifying and Saving the Configuration
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
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Configuring Optional Features on the eGTP S-GW
The configuration examples in this section are optional and provided to cover the most common uses of the eGTP SGW in a live network. The intent of these examples is to provide a base configuration for testing.
The following optional configurations are provided in this section:
 Configuring the GTP Echo Timer
 Configuring GTPP Offline Accounting on the S-GW
 Configuring Diameter Offline Accounting on the S-GW
 Configuring APN-level Traffic Policing on the S-GW
 Configuring X.509 Certificate-based Peer Authentication
 Configuring Dynamic Node-to-Node IP Security on the S1-U and S5 Interfaces
 Configuring ACL-based Node-to-Node IP Security on the S1-U and S5 Interfaces
 Configuring S4 SGSN Handover Capability
Configuring the GTP Echo Timer
The GTP echo timer on the ASR5x00 S-GW can be configured to support two different types of path management:
default and dynamic. This timer can be configured on the GTP-C and/or the GTP-U channels.
Default GTP Echo Timer Configuration
The following examples describe the configuration of the default eGTP-C and GTP-U interface echo timers:
eGTP-C
configure
configure
context <context_name>
egtp-service <egtp_service_name>
gtpc echo-interval <seconds>
gtpc echo-retransmission-timeout <seconds>
gtpc max-retransmissions <num>
end
Notes:
 This configuration can be used in either the ingress context supporting the S1 -U and/or S11 interfaces with the
eNodeB and MME respectively; and the egress context supporting the S5/S8 interface with the P-GW.
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 The following diagram describes a failure and recovery scenario using default settings of the three gtpc
commands in the example above:
 The multiplier (x2) is system-coded and cannot be configured.
GTP-U
configure
configure
context <context_name>
gtpu-service <gtpu_service_name>
echo-interval <seconds>
echo-retransmission-timeout <seconds>
max-retransmissions <num>
end
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Notes:
 This configuration can be used in either the ingress context supporting the S1 -U interfaces with the eNodeB and
the egress context supporting the S5/S8 interface with the P-GW.
 The following diagram describes a failure and recovery scenario using default settings of the three GTP-U
commands in the example above:
 The multiplier (x2) is system-coded and cannot be configured.
Dynamic GTP Echo Timer Configuration
The following examples describe the configuration of the dynamic eGTP-C and GTP-U interface echo timers:
eGTP-C
configure
configure
context <context_name>
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egtp-service <egtp_service_name>
gtpc echo-interval <seconds> dynamic smooth-factor <multiplier>
gtpc echo-retransmission-timeout <seconds>
gtpc max-retransmissions <num>
end
Notes:
 This configuration can be used in either the ingress context supporting the S1-U and/or S11 interfaces with the
eNodeB and MME respectively; and the egress context supporting the S5/S8 interface with the P-GW.
 The following diagram describes a failure and recovery scenario using default settings of the three gtpc
commandsin the example above and an example round trip timer (RTT) of six seconds:
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 The multiplier (x2) and the 100 second maximum are system-coded and cannot be configured.
GTP-U
configure
configure
context <context_name>
gtpu-service <gtpu_service_name>
echo-interval <seconds> dynamic smooth-factor <multiplier>
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echo-retransmission-timeout <seconds>
max-retransmissions <num>
end
Notes:
 This configuration can be used in either the ingress context supporting the S1-U interfaces with the eNodeB and
the egress context supporting the S5/S8 interface with the P-GW.
 The following diagram describes a failure and recovery scenario using default settings of the three gtpc
commandsin the example above and an example round trip timer (RTT) of six seconds:
 The multiplier (x2) and the 100 second maximum are system-coded and cannot be configured.
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Configuring GTPP Offline Accounting on the S-GW
By default the S-GW service supports GTPP accounting. To provide GTPP offline charging during, for example,
scenarios where the foreign P-GW does not, configure the S-GW with the example parameters below:
configure
gtpp single-source
context <saegw_context_name>
subscriber default
accounting mode gtpp
exit
gtpp group default
gtpp charging-agent address <gz_ipv4_address>
gtpp echo-interval <seconds>
gtpp attribute diagnostics
gtpp attribute local-record-sequence-number
gtpp attribute node-id-suffix <string>
gtpp dictionary <name>
gtpp server <ipv4_address> priority <num>
gtpp server <ipv4_address> priority <num> node-alive enable
exit
policy accounting <gz_policy_name>
accounting-level {type}
operator-string <string>
cc profile <index> buckets <num>
cc profile <index> interval <seconds>
cc profile <index> volume total <octets>
exit
sgw-service <sgw_service_name>
accounting context <saegw_context_name> gtpp group default
associate accounting-policy <gz_policy_name>
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exit
exit
context <saegw_context_name>
interface <gz_interface_name>
ip address <address>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <gz_interface_name> <saegw_context_name>
end
Notes:
 gtpp single-source is enabled to allow the system to generate requests to the accounting server using a
single UDP port (by way of a AAA proxy function) rather than each AAA manager generating requests on
unique UDP ports.
 gtpp is the default option for the accounting mode command.
 An accounting mode configured for the call-control profile will override this setting.
 accounting-level types are: flow, PDN, PDN-QCI, QCI, and subscriber. Refer to the Accounting Profile
Configuration Mode Commands chapter in the Command Line Interface Reference for more information on
this command.
Configuring Diameter Offline Accounting on the S-GW
By default the S-GW service supports GTPP accounting. You can enable accounting via RADIUS/Diameter (Rf) for the
S-GW service. To provide Rf offline charging during, for example, scenarios where the foreign P-GW does not,
configure the S-GW with the example parameters below:
configure
operator-policy name <policy_name>
associate call-control-profile <call_cntrl_profile_name>
exit
call-control-profile <call_cntrl_profile_name>
accounting mode radius-diameter
exit
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lte-policy
subscriber-map <map_name>
precendence <number> match-criteria all operator-policy-name <policy_name>
exit
exit
context <saegw_context_name>
policy accounting <rf_policy_name>
accounting-level {type}
operator-string <string>
exit
sgw-service <sgw_service_name>
associate accounting-policy <rf_policy_name>
associate subscriber-map <map_name>
exit
aaa group <rf-radius_group_name>
radius attribute nas-identifier <id>
radius accounting interim interval < seconds>
radius dictionary <name>
radius mediation-device accounting server <address> key <key>
diameter authentication dictionary < name>
diameter accounting dictionary <name>
diameter accounting endpoint <rf_cfg_name>
diameter accounting server <rf_cfg_name> priority <num>
exit
diameter endpoint <rf_cfg_name>
use-proxy
origin realm <realm_name>
origin host <name> address <rf_ipv4_address>
peer <rf_cfg_name> realm <name> address <ofcs_ipv4_or_ipv6_addr>
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route-entry peer <rf_cfg_name>
exit
exit
context <saegw_context_name>
interface <rf_interface_name>
ip address <rf_ipv4_address>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <rf_interface_name> <saegw_context_name>
end
Notes:
 accounting-level types are: flow, PDN, PDN-QCI, QCI, and subscriber. Refer to the Accounting Profile
Configuration Mode Commands chapter in the Command Line Interface Reference for more information on
this command.
 The Rf interface IP address can also be specified as an IPv6 address using the ipv6 address command.
Configuring APN-level Traffic Policing on the S-GW
To enable traffic policing for scenarios where the foreign subscriber’s P-GW doesn’t enforce it, use the following
configuration example:
configure
apn-profile <apn_profile_name>
qos rate-limit downlink non-gbr-qci committed-auto-readjust duration <seconds>
exceed-action {action} violate-action {action}
qos rate-limit uplink non-gbr-qci committed-auto-readjust duration <seconds>
exceed-action {action} violate-action {action}
exit
operator-policy name <policy_name>
apn default-apn-profile <apn_profile_name>
exit
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lte-policy
subscriber-map <map_name>
precendence <number> match-criteria all operator-policy-name <policy_name>
exit
sgw-service <sgw_service_name>
associate subscriber-map <map_name>
end
Notes:
 For the qos rate-limit command, the actions supported for violate-action and exceed-action are:
drop , lower-ip-precedence , and transmit .
Configuring X.509 Certificate-based Peer Authentication
The configuration example in this section enables X.509 certificate-based peer authentication, which can be used as the
authentication method for IP Security on the S-GW.
Important: Use of the IP Security feature requires that a valid license key be installed. Contact your local Sales
or Support representative for information on how to obtain a license.
The following configuration example enables X.509 certificate-based peer authentication on the S-GW.
In Global Configuration Mode, specify the name of the X.509 certificate and CA certificate, as follows:
configure
certificate name <cert_name> pem url <cert_pem_url> private-key pem url
<private_key_url>
ca-certificate name <ca_cert_name> pem url <ca_cert_url>
end
Notes:
 The certificate name and ca-certificate list ca-cert-name commands specify the X.509
certificate and CA certificate to be used.
 The PEM-formatted data for the certificate and CA certificate can be specified, or the information can be read
from a file via a specified URL as shown in this example.
When creating the crypto template for IPSec in Context Configuration Mode, bind the X.509 certificate and CA
certificate to the crypto template and enable X.509 certificate-based peer authentication for the local and remote nodes,
as follows:
configure
context <saegw_context_name>
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crypto template <crypto_template_name> ikev2-dynamic
certificate name <cert_name>
ca-certificate list ca-cert-name <ca_cert_name>
authentication local certificate
authentication remote certificate
end
Notes:
 A maximum of sixteen certificates and sixteen CA certificates are supported per system. One certificate is
supported per service, and a maximum of four CA certificates can be bound to one crypto template.
 The certificate name and ca-certificate list ca-cert-name commands bind the certificate and CA
certificate to the crypto template.
 The authentication local certificate and authentication remote certificate commands
enable X.509 certificate-based peer authentication for the local and remote nodes.
Configuring Dynamic Node-to-Node IP Security on the S1-U and S5 Interfaces
The configuration example in this section creates IPSec/IKEv2 dynamic node-to-node tunnel endpoints on the S1-U and
S5 interfaces.
Important: Use of the IP Security feature requires that a valid license key be installed. Contact your local Sales
or Support representative for information on how to obtain a license.
The following configuration examples are included in this section:
 Creating and Configuring an IPSec Transform Set
 Creating and Configuring an IKEv2 Transform Set
 Creating and Configuring a Crypto Template
 Binding the S1-U and S5 IP Addresses to the Crypto Template
Creating and Configuring an IPSec Transform Set
The following example configures an IPSec transform set, which is used to define the security association that
determines the protocols used to protect the data on the interface:
configure
context <saegw_context_name>
ipsec transform-set <ipsec_transform-set_name>
encryption aes-cbc-128
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group none
hmac sha1-96
mode tunnel
end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IPSec transform sets configured on the system.
 The group none command specifies that no crypto strength is included and that Perfect Forward Secrecy is
disabled. This is the default setting for IPSec transform sets configured on the system.
 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for IPSec
transform sets configured on the system.
 The mode tunnel command specifies that the entire packet is to be encapsulated by the IPSec header, including
the IP header. This is the default setting for IPSec transform sets configured on the system.
Creating and Configuring an IKEv2 Transform Set
The following example configures an IKEv2 transform set:
configure
context <saegw_context_name>
ikev2-ikesa transform-set <ikev2_transform-set_name>
encryption aes-cbc-128
group 2
hmac sha1-96
lifetime <sec>
prf sha1
end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IKEv2 transform sets configured on the system.
 The group 2 command specifies the Diffie-Hellman algorithm as Group 2, indicating medium security. The
Diffie-Hellman algorithm controls the strength of the crypto exponentials. This is the default setting for IKEv2
transform sets configured on the system.
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 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for
IKEv2 transform sets configured on the system.
 The lifetime command configures the time the security key is allowed to exist, in seconds.
 The prf command configures the IKE Pseudo-random Function, which produces a string of bits that cannot be
distinguished from a random bit string without knowledge of the secret key. The sha1 keyword uses a 160-bit
secret key to produce a 160-bit authenticator value. This is the default setting for IKEv2 transform sets
configured on the system.
Creating and Configuring a Crypto Template
The following example configures an IKEv2 crypto template:
configure
context <saegw_context_name>
crypto template <crypto_template_name> ikev2-dynamic
ikev2-ikesa transform-set list <name1> . . . <name6>
ikev2-ikesa rekey
payload <name> match childsa match ipv4
ipsec transform-set list <name1> . . . <name4>
rekey
end
Notes:
 The ikev2-ikesa transform-set list command specifies up to six IKEv2 transform sets.
 The ipsec transform-set list command specifies up to four IPSec transform sets.
Binding the S1-U and S5 IP Addresses to the Crypto Template
The following example configures the binding of the S1-U and S5 interfaces to the crypto template.
configure
context <saegw_context_name>
gtpu-service <gtpu_ingress_service_name>
bind ipv4-address <s1-u_interface_ip_address> crypto-template
<enodeb_crypto_template>
exit
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egtp-service <egtp_ingress_service_name>
interface-type interface-sgw-ingress
associate gtpu-service <gtpu_ingress_service_name>
gtpc bind address <s1u_interface_ip_address>
exit
exit
context <sgw_egress_context_name>
gtpu-service <gtpu_egress_service_name>
bind ipv4-address <s5_interface_ip_address> crypto-template
<enodeb_crypto_template>
exit
egtp-service <egtp_egress_service_name>
interface-type interface-sgw-egress
associate gtpu-service <gtpu_egress_service_name>
gtpc bind address <s5_interface_ip_address>
exit
exit
context <saegw_context_name>
sgw-service <sgw_service_name> -noconfirm
egtp-service ingress service <egtp_ingress_service_name>
egtp-service egress context <sgw_egress_context_name>
end
Notes:
 The bind command in the GTP-U ingress and egress service configuration can also be specified as an IPv6
address using the ipv6-address command.
Configuring ACL-based Node-to-Node IP Security on the S1-U and S5
Interfaces
The configuration example in this section creates IKEv2/IPSec ACL-based node-to-node tunnel endpoints on the S1-U
and S5 interfaces.
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Important: Use of the IP Security feature requires that a valid license key be installed. Contact your local Sales
or Support representative for information on how to obtain a license.
The following configuration examples are included in this section:
 Creating and Configuring a Crypto Access Control List
 Creating and Configuring an IPSec Transform Set
 Creating and Configuring an IKEv2 Transform Set
 Creating and Configuring a Crypto Map
Creating and Configuring a Crypto Access Control List
The following example configures a crypto ACL (Access Control List), which defines the matching crite ria used for
routing subscriber data packets over an IPSec tunnel:
configure
context <saegw_context_name>
ip access-list <acl_name>
permit tcp host <source_host_address> host <dest_host_address>
end
Notes:
 The permit command in this example routes IPv4 traffic from the server with the specified source host IPv4
address to the server with the specified destination host IPv4 address.
Creating and Configuring an IPSec Transform Set
The following example configures an IPSec transform set which is used to define the security association that
determines the protocols used to protect the data on the interface:
configure
context <saegw_context_name>
ipsec transform-set <ipsec_transform-set_name>
encryption aes-cbc-128
group none
hmac sha1-96
mode tunnel
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end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IPSec transform sets configured on the system.
 The group none command specifies that no crypto strength is included and that Perfect Forward Secrecy is
disabled. This is the default setting for IPSec transform sets configured on the system.
 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for IPSec
transform sets configured on the system.
 The mode tunnel command specifies that the entire packet is to be encapsulated by the IPSec header including
the IP header. This is the default setting for IPSec transform sets configured on the system.
Creating and Configuring an IKEv2 Transform Set
The following example configures an IKEv2 transform set:
configure
context <saegw_context_name>
ikev2-ikesa transform-set <ikev2_transform-set_name>
encryption aes-cbc-128
group 2
hmac sha1-96
lifetime <sec>
prf sha1
end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IKEv2 transform sets configured on the system.
 The group 2 command specifies the Diffie-Hellman algorithm as Group 2, indicating medium security. The
Diffie-Hellman algorithm controls the strength of the crypto exponentials. This is the default setting for IKEv2
transform sets configured on the system.
 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for
IKEv2 transform sets configured on the system.
 The lifetime command configures the time the security key is allowed to exist, in seconds.
 The prf command configures the IKE Pseudo-random Function which produces a string of bits that cannot be
distinguished from a random bit string without knowledge of the secret key. The sha1 keyword uses a 160-bit
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secret key to produce a 160-bit authenticator value. This is the default setting for IKEv2 transform sets
configured on the system.
Creating and Configuring a Crypto Map
The following example configures an IKEv2 crypto map and applies it to the S1 -U interface:
configure
context <saegw_context_name>
crypto map <crypto_map_name> ikev2-ipv4
match address <acl_name>
peer <ipv4_address>
authentication local pre-shared-key key <text>
authentication remote pre-shared-key key <text>
ikev2-ikesa transform-set list <name1> . . . <name6>
payload <name> match ipv4
lifetime <seconds>
ipsec transform-set list <name1> . . . <name4>
exit
exit
interface <s1-u_intf_name>
ip address <ipv4_address>
crypto-map <crypto_map_name>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <s1_u_intf_name> <saegw_context_name>
end
Notes:
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 The type of crypto map used in this example is IKEv2-IPv4 for IPv4 addressing. An IKEv2-IPv6 crypto map can
also be used for IPv6 addressing.
 The ipsec transform-set list command specifies up to four IPSec transform sets.
The following example configures an IKEv2 crypto map and applies it to the S5 interface:
configure
context <sgw_egress_context_name>
crypto map <crypto_map_name> ikev2-ipv4
match address <acl_name>
peer <ipv4_address>
authentication local pre-shared-key key <text>
authentication remote pre-shared-key key <text>
payload <name> match ipv4
lifetime <seconds>
ipsec transform-set list <name1> . . . <name4>
exit
exit
interface <s5_intf_name>
ip address <ipv4_address>
crypto map <crypto_map_name>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <s5_intf_name> <sgw_egress_context_name>
end
Notes:
 The type of crypto map used in this example is IKEv2-IPv4 for IPv4 addressing. An IKEv2-IPv6 crypto map can
also be used for IPv6 addressing.
 The ipsec transform-set list command specifies up to four IPSec transform sets.
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Configuring S4 SGSN Handover Capability
This configuration example configures an S4 interface supporting inter-RAT handovers between the S-GW and a S4
SGSN.
Use the following example to configure this feature:
configure
context <saegw_context_name> -noconfirm
interface <s4_interface_name>
ip address <ipv4_address_primary>
ip address <ipv4_address_secondary>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <s4_interface_name> <saegw_context_name>
exit
context <saegw_context_name> -noconfirm
gtpu-service <s4_gtpu_ingress_service_name>
bind ipv4-address <s4_interface_ip_address>
exit
egtp-service <s4_egtp_ingress_service_name>
interface-type interface-sgw-ingress
validation-mode default
associate gtpu-service <s4_gtpu_ingress_service_name>
gtpc bind address <s4_interface_ip_address>
exit
sgw-service <sgw_service_name> -noconfirm
associate ingress egtp-service <s4_egtp_ingress_service_name>
end
Notes:
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 The S4 interface IP address(es) can also be specified as IPv6 addresses using the ipv6 address command.
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Configuring an eGTP P-GW Service
This section provides a high-level series of steps and the associated configuration file examples for configuring the
system to perform as an eGTP P-GW in a test environment. Information provided in this section includes the following:
 Information Required
 How This Configuration Works
 eGTP P-GW Configuration
 DHCP Service Configuration
 DHCPv6 Service Configuration
Information Required
The following sections describe the minimum amount of information required to configure and make the P-GW
operational on the network. To make the process more efficient, it is recommended that this information be available
prior to configuring the system.
There are additional configuration parameters that are not described in this section. These parameters deal mostly with
fine-tuning the operation of the P-GW in the network. Information on these parameters can be found in the appropriate
sections of the Command Line Interface Reference.
Required P-GW Context Configuration Information
The following table lists the information that is required to configure the P-GW context on a P-GW.
Table 15.
Required Information for P-GW (SAEGW) Context Configuration
Required
Information
Description
P-GW context
name
An identification string from 1 to 79 characters (alpha and/or numeric) by which the P-GW context will be
recognized by the system.
Accounting
policy name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the accounting policy will be
recognized by the system. The accounting policy is used to set parameters for the Rf (off-line charging)
interface.
S5/S8 Interface Configuration (To/from S-GW)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface will be
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and
subnet
IPv4 or IPv6 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
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Required
Information
Description
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number where
the line card resides followed by the number of the physical connector on the card. For example, port 17/1
identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP
address
Used when configuring static IP routes from the interface(s) to a specific network.
GTP-U Service Configuration
GTP-U service
name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the GTP-U service will be
recognized by the system.
IP address
S5/S8 interface IPv4 address.
P-GW Service Configuration
P-GW service
name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the P-GW service will be
recognized by the system.
Multiple names are needed if multiple P-GW services will be used.
PLMN ID
MCC number: The mobile country code (MCC) portion of the PLMN’s identifier (an integer value between
100 and 999).
MNC number: The mobile network code (MNC) portion of the PLMN’s identifier (a 2 or 3 digit integer value
between 00 and 999).
eGTP Service Configuration
eGTP Service
Name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the eGTP service will be
recognized by the system.
Required PDN Context Configuration Information
The following table lists the information that is required to configure the PDN context on a P-GW.
Table 16.
Required Information for PDN Context Configuration
Required
Information
Description
PDN context name
An identification string from 1 to 79 characters (alpha and/or numeric) by which the PDN context is
recognized by the system.
IP Address Pool Configuration
IPv4 address pool
name and range
An identification string between 1 and 31 characters (alpha and/or numeric) by which the IPv4 pool is
recognized by the system.
Multiple names are needed if multiple pools will be configured.
A range of IPv4 addresses defined by a starting address and an ending address.
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Required
Information
Description
IPv6 address pool
name and range
An identification string between 1 and 31 characters (alpha and/or numeric) by which the IPv6 pool is
recognized by the system.
Multiple names are needed if multiple pools will be configured.
A range of IPv6 addresses defined by a starting address and an ending address.
Access Control List Configuration
IPv4 access list
name
An identification string between 1 and 47 characters (alpha and/or numeric) by which the IPv4 access list is
recognized by the system.
Multiple names are needed if multiple lists will be configured.
IPv6 access list
name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the IPv6 access list is
recognized by the system.
Multiple names are needed if multiple lists will be configured.
Deny/permit type
The types are:
 any
Readdress or
redirect type

by host IP address

by IP packets

by source ICMP packets

by source IP address masking

by TCP/UDP packets
The types are
 readdress server

redirect context

redirect css delivery-sequence

redirect css service

redirect nexthop
SGi Interface Configuration (To/from IPv4 PDN)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and
subnet
IPv4 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number where
the line card resides followed by the number of the physical connector on the card. For example, port 17/1
identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP address
Used when configuring static IP routes from the interface(s) to a specific network.
SGi Interface Configuration (To/from IPv6 PDN)
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Required
Information
Description
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and
subnet
IPv6 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number where
the line card resides followed by the number of the physical connector on the card. For example, port 17/1
identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP address
Used when configuring static IP routes from the interface(s) to a specific network.
Required AAA Context Configuration Information
The following table lists the information that is required to configure the AAA context on a P-GW.
Table 17.
Required
Information
Required Information for AAA Context Configuration
Description
Gx Interface Configuration (to PCRF)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and
subnet
IPv4 or IPv6 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number where
the line card resides followed by the number of the physical connector on the card. For example, port 17/1
identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP
address
Used when configuring static IP routes from the interface(s) to a specific network.
Gx Diameter Endpoint Configuration
End point name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the Gx Diameter endpoint
configuration is recognized by the system.
Origin realm
name
An identification string between 1 through 127 characters.
The realm is the Diameter identity. The originator’s realm is present in all Diameter messages and is typically
the company or service name.
Origin host name
An identification string from 1 to 255 characters (alpha and/or numeric) by which the Gx origin host is
recognized by the system.
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Required
Information
Description
Origin host
address
The IP address of the Gx interface.
Peer name
The Gx endpoint name described above.
Peer realm name
The Gx origin realm name described above.
Peer address and
port number
The IP address and port number of the PCRF.
Route-entry peer
The Gx endpoint name described above.
Gy Interface Configuration (to on-line charging server)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and
subnet
IPv4 or IPv6 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number where
the line card resides followed by the number of the physical connector on the card. For example, port 17/1
identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP
address
Used when configuring static IP routes from the interface(s) to a specific network.
Gy Diameter Endpoint Configuration
End point name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the Gy Diameter endpoint
configuration is recognized by the system.
Origin realm
name
An identification string between 1 through 127 characters.
The realm is the Diameter identity. The originator’s realm is present in all Diameter messages and is typically
the company or service name.
Origin host name
An identification string from 1 to 255 characters (alpha and/or numeric) by which the Gy origin host is
recognized by the system.
Origin host
address
The IP address of the Gy interface.
Peer name
The Gy endpoint name described above.
Peer realm name
The Gy origin realm name described above.
Peer address and
port number
The IP address and port number of the OCS.
Route-entry peer
The Gy endpoint name described above.
Gz Interface Configuration (to off-line charging server)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
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Required
Information
Description
IP address and
subnet
IPv4 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number where
the line card resides followed by the number of the physical connector on the card. For example, port 17/1
identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP
address
Used when configuring static IP routes from the interface(s) to a specific network.
Rf Interface Configuration (to off-line charging server)
Interface name
An identification string between 1 and 79 characters (alpha and/or numeric) by which the interface is
recognized by the system.
Multiple names are needed if multiple interfaces will be configured.
IP address and
subnet
IPv4 or IPv6 addresses assigned to the interface.
Multiple addresses and subnets are needed if multiple interfaces will be configured.
Physical port
number
The physical port to which the interface will be bound. Ports are identified by the chassis slot number where
the line card resides followed by the number of the physical connector on the card. For example, port 17/1
identifies connector number 1 on the card in slot 17.
A single physical port can facilitate multiple interfaces.
Gateway IP
address
Used when configuring static IP routes from the interface(s) to a specific network.
Rf Diameter Endpoint Configuration
End point name
An identification string from 1 to 63 characters (alpha and/or numeric) by which the Rf Diameter endpoint
configuration is recognized by the system.
Origin realm
name
An identification string between 1 through 127 characters.
The realm is the Diameter identity. The originator’s realm is present in all Diameter messages and is typically
the company or service name.
Origin host name
An identification string from 1 to 255 characters (alpha and/or numeric) by which the Rf origin host is
recognized by the system.
Origin host
address
The IP address of the Rf interface.
Peer name
The Rf endpoint name described above.
Peer realm name
The Rf origin realm name described above.
Peer address and
port number
The IP address and port number of the OFCS.
Route-entry peer
The Rf endpoint name described above.
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How This Configuration Works
The following figure and supporting text describe how this configuration with a single source and destination context is
used by the system to process a subscriber call originating from the GTP LTE network.
1. The S-GW establishes the S5/S8 connection by sending a Create Session Request message to the P-GW
including an Access Point name (APN).
2. The P-GW service determines which context to use to provide AAA functionality for the session. This process is
described in the How the System Selects Contexts section located in the Understanding the System Operation
and Configuration chapter of the System Administration Guide.
3. The P-GW uses the configured Gx Diameter endpoint to establish the IP-CAN session.
4. The P-GW sends a CC-Request (CCR) message to the PCRF to indicate the establishment of the IP-CAN session
and the PCRF acknowledges with a CC-Answer (CCA).
5. The P-GW uses the APN configuration to select the PDN context. IP addresses are assigned from the IP pool
configured in the selected PDN context.
6. The P-GW responds to the S-GW with a Create Session Response message including the assigned address and
additional information.
7. The S5/S8 data plane tunnel is established and the P-GW can forward and receive packets to/from the PDN.
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eGTP P-GW Configuration
To configure the system to perform as an eGTP P-GW:
Step 1
Set system configuration parameters such as activating PSCs by applying the example configurations found in the
System Administration Guide.
Step 2
Set initial configuration parameters such as creating contexts and services by applying the example configurations
found in the Initial Configuration section of this chapter.
Step 3
Configure the system to perform as an eGTP P-GW and set basic P-GW parameters such as eGTP interfaces and IP
routes by applying the example configurations presented in the P-GW Service Configuration section.
Step 4
Configure the PDN context by applying the example configuration in the P-GW PDN Context Configuration section.
Step 5
Enable and configure the active charging service for Gx interface support by applying the example configuration in the
Active Charging Service Configuration section.
Step 6
Create a AAA context and configure parameters for policy by applying the example configuration in the Policy
Configuration section.
Step 7
Verify and save the configuration by following the steps found in the Verifying and Saving the Configuration section.
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Initial Configuration
Step 1
Create the context where the eGTP service will reside by applying the example configuration in the Creating and
Configuring an eGTP P-GW Context section.
Step 2
Create and configure APNs in the P-GW context by applying the example configuration in the Creating and
Configuring APNs in the P-GW Context section.
Step 3
Create and configure AAA server groups in the P-GW context by applying the example configuration in the Creating
and Configuring AAA Groups in the P-GW Context section.
Step 4
Create an eGTP service within the newly created context by applying the example configuration in the Creating and
Configuring an eGTP Service section.
Step 5
Create and configure a GTP-U service within the P-GW context by applying the example configuration in the Creating
and Configuring a GTP-U Service section.
Step 6
Create a context through which the interface to the PDN will reside by applying the example configuration in the
Creating a P-GW PDN Context section.
Creating and Configuring an eGTP P-GW Context
Use the following example to create a P-GW context, create an S5/S8 IPv4 interface (for data traffic to/from the S-GW),
and bind the S5/S8 interface to a configured Ethernet port:
configure
gtpp single-source
context <saegw_context_name> -noconfirm
interface <s5s8_interface_name>
ip address <ipv4_address>
exit
gtpp group default
gtpp charging-agent address <gz_ipv4_address>
gtpp echo-interval <seconds>
gtpp attribute diagnostics
gtpp attribute local-record-sequence-number
gtpp attribute node-id-suffix <string>
gtpp dictionary <name>
gtpp server <ipv4_address> priority <num>
gtpp server <ipv4_address> priority <num> node-alive enable
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exit
policy accounting <rf_policy_name> -noconfirm
accounting-level {level_type}
accounting-event-trigger interim-timeout action stop-start
operator-string <string>
cc profile <index> interval <seconds>
exit
exit
subscriber default
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <s5s8_interface_name> <saegw_context_name>
end
Notes:
 gtpp single-source is enabled to allow the system to generate requests to the accounting server using a
single UDP port (by way of a AAA proxy function) rather than each AAA manager generating requests on
unique UDP ports.
 The S5/S8 (P-GW to S-GW) interface IP address can also be specified as an IPv6 address using the ipv6
address command.
 Set the accounting policy for the Rf (off-line charging) interface. The accounting level types are: flow, PDN,
PDN-QCI, QCI, and subscriber. Refer to the Accounting Profile Configuration Mode Commands chapter in the
Command Line Interface Reference for more information on this command.
 Set the GTPP group setting for Gz accounting.
Creating and Configuring APNs in the P-GW Context
Use the following configuration to create an APN:
configure
context <saegw_context_name> -noconfirm
apn <name>
accounting-mode radius-diameter
associate accounting-policy <rf_policy_name>
ims-auth-service <gx_ims_service_name>
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aaa group <rf-radius_group_name>
dns primary <ipv4_address>
dns secondary <ipv4_address>
ip access-group <name> in
ip access-group <name> out
mediation-device context-name <saegw_context_name>
ip context-name <pdn_context_name>
ipv6 access-group <name> in
ipv6 access-group <name> out
active-charging rulebase <name>
end
Notes:
 The IMS Authorization Service is created and configured in the AAA context.
 Multiple APNs can be configured to support different domain names.
 The associate accounting-policy command is used to associate a pre-configured accounting policy with this
APN. Accounting policies are configured in the P-GW context. An example is located in the Creating and
Configuring an eGTP P-GW Context section above.
Use the following configuration to create an APN that includes Gz interface parameters:
configure
context <saegw_context_name> -noconfirm
apn <name>
bearer-control-mode mixed
selection-mode sent-by-ms
accounting-mode gtpp
gtpp group default accounting-context <aaa_context_name>
ims-auth-service <gx_ims_service_name>
ip access-group <name> in
ip access-group <name> out
ip context-name <pdn_context_name>
active-charging rulebase <gz_rulebase_name>
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end
Notes:
 The IMS Authorization Service is created and configured in the AAA context.
 Multiple APNs can be configured to support different domain names.
 The accounting-mode GTPP and GTPP group commands configure this APN for Gz accounting.
Creating and Configuring AAA Groups in the P-GW Context
Use the following example to create and configure AAA groups supporting RADIUS and Rf accounting:
configure
context <saegw_context_name> -noconfirm
aaa group <rf-radius_group_name>
radius attribute nas-identifier <id>
radius accounting interim interval < seconds>
radius dictionary <name>
radius mediation-device accounting server <address> key <key>
diameter authentication dictionary < name>
diameter accounting dictionary <name>
diameter accounting endpoint <rf_cfg_name>
diameter accounting server <rf_cfg_name> priority <num>
exit
aaa group default
radius attribute nas-ip-address address <ipv4_address>
radius accounting interim interval <seconds>
diameter authentication dictionary < name>
diameter accounting dictionary <name>
diameter accounting endpoint <rf_cfg_name>
diameter accounting server <rf_cfg_name> priority <num>
Creating and Configuring an eGTP Service
Use the following configuration example to create the eGTP service:
configure
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context <saegw_context_name>
egtp-service <egtp_service_name> -noconfirm
interface-type interface-pgw-ingress
validation mode default
associate gtpu-service <gtpu_service_name>
gtpc bind address <s5s8_interface_address>
end
Notes:
 Co-locating a GGSN service on the same ASR 5x00 requires that the gtpc bind address command uses the
same IP address the GGSN service is bound to.
Creating and Configuring a GTP-U Service
Use the following configuration example to create the GTP-U service:
configure
context <saegw_context_name>
gtpu-service <gtpu_service_name> -noconfirm
bind ipv4-address <s5s8_interface_address>
end
Notes:
 The bind command can also be specified as an IPv6 address using the ipv6-address command.
Creating a P-GW PDN Context
Use the following example to create a P-GW PDN context and Ethernet interface, and bind the interface to a configured
Ethernet port.
configure
context <pdn_context_name> -noconfirm
interface <sgi_ipv4_interface_name>
ip address <ipv4_address>
interface <sgi_ipv6_interface_name>
ipv6 address <address>
end
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P-GW Service Configuration
Step 1
Configure the P-GW service by applying the example configuration in the Configuring the P-GW Service section.
Step 2
Specify an IP route to the eGTP Serving Gateway by applying the example configuration in the Configuring a Static IP
Route section.
Configuring the P-GW Service
Use the following example to configure the P-GW service:
configure
context <saegw_context_name>
pgw-service <pgw_service_name> -noconfirm
plmn id mcc <id> mnc <id>
associate egtp-service <egtp_service_name>
associate qci-qos-mapping <name>
end
Notes:
 QCI-QoS mapping configurations are created in the AAA context. Refer to the Configuring QCI-QoS Mapping
section for more information.
 Co-locating a GGSN service on the same ASR 5x00 requires the configuration of the associate ggsnservie name command within the P-GW service.
Configuring a Static IP Route
Use the following example to configure an IP Route for control and user plane data communication with an eGTP
Serving Gateway:
configure
context <saegw_context_name>
ip route <sgw_ip_addr/mask> <sgw_next_hop_addr> <pgw_intrfc_name>
end
P-GW PDN Context Configuration
Use the following example to configure an IP Pool and APN, and bind a port to the interface in the PDN context:
configure
context <pdn_context_name> -noconfirm
interface <sgi_ipv4_interface_name>
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ip address <ipv4_address>
exit
interface <sgi_ipv6_interface_name>
ip address <ipv6_address>
exit
ip pool <name> range <start_address end_address> public <priority>
ipv6 pool <name> range <start_address end_address> public <priority>
subscriber default
exit
ip access-list <name>
redirect css service <name> any
permit any
exit
ipv6 access-list <name>
redirect css service <name> any
permit any
exit
aaa group default
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <sgi_ipv4_interface_name> <pdn_context_name>
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <sgi_ipv6_interface_name> <pdn_context_name>
end
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Active Charging Service Configuration
Use the following example to enable and configure active charging:
configure
require active-charging optimized-mode
active-charging service <name>
ruledef <name>
<rule_definition>
.
.
<rule_definition>
exit
ruledef default
ip any-match = TRUE
exit
ruledef icmp-pkts
icmp any-match = TRUE
exit
ruledef qci3
icmp any-match = TRUE
exit
ruledef static
icmp any-match = TRUE
exit
charging-action <name>
<action>
.
.
<action>
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exit
charging-action icmp
billing-action egcdr
exit
charging-action qci3
content-id <id>
billing-action egcdr
qos-class-identifier <id>
allocation-retention-priority <priority>
tft-packet-filter qci3
exit
charging-action static
service-identifier <id>
billing-action egcdr
qos-class-identifier <id>
allocation-retention-priority <priority>
tft-packet-filter qci3
exit
rulebase default
exit
rulebase <name>
<rule_base>
.
.
<rule_base>
exit
rulebase <gx_rulebase_name>
dynamic-rule order first-if-tied
egcdr tariff minute <minute> hour <hour>(optional)
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billing-records egcdr
action priority 5 dynamic-only ruledef qci3 charging-action qci3
action priority 100 ruledef static charging-action static
action priority 500 ruledef default charging-action icmp
action priority 570 ruledef icmp-pkts charging-action icmp
egcdr threshold interval <interval>
egcdr threshold volume total <bytes>
end
Notes:
 A rule base is a collection of rule definitions and associated charging actions.
 As depicted above, multiple rule definitions, charging actions, and rule bases can be configured to support a
variety of charging scenarios.
 Charging actions define the action to take when a rule definition is matched.
 Routing and/or charging rule definitions can be created/configured. The maximum number of routing rul e
definitions that can be created is 256. The maximum number of charging rule definitions is 2048.
 The billing-action egcdr command in the charging-action qc13 , icmp , and static examples is required for Gz
accounting.
 The Gz rulebase example supports the Gz interface for off-line charging. The billing-records egcdr
command is required for Gz accounting. All other commands are optional.
Policy Configuration
Step 1
Configure the policy and accounting interfaces by applying the example configuration in the Creating and Configuring
the AAA Context section.
Step 2
Create and configure QCI to QoS mapping by applying the example configuration in the Configuring QCI-QoS
Mapping section.
Creating and Configuring the AAA Context
Use the following example to create and configure a AAA context including diameter support and policy control, and
bind Ethernet ports to interfaces supporting traffic between this context and a PCRF, an OCS, and an OFCS:
configure
context <aaa_context_name> -noconfirm
interface <gx_interface_name>
ipv6 address <address>
exit
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interface <gy_interface_name>
ipv6 address <address>
exit
interface <gz_interface_name>
ip address <ipv4_address>
exit
interface <rf_interface_name>
ip address <ipv4_address>
exit
subscriber default
exit
ims-auth-service <gx_ims_service_name>
p-cscf discovery table <#> algorithm round-robin
p-cscf table <#> row-precedence <#> ipv6-address <pcrf_ipv6_adr>
policy-control
diameter origin endpoint <gx_cfg_name>
diameter dictionary <name>
diameter host-select table <#> algorithm round-robin
diameter host-select row-precedence <#> table <#> host <gx_cfg_name>
exit
exit
diameter endpoint <gx_cfg_name>
origin realm <realm_name>
origin host <name> address <aaa_ctx_ipv6_address>
peer <gx_cfg_name> realm <name> address <pcrf_ipv4_or_ipv6_addr>
route-entry peer <gx_cfg_name>
exit
diameter endpoint <gy_cfg_name>
origin realm <realm_name>
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origin host <name> address <gy_ipv6_address>
connection retry-timeout <seconds>
peer <gy_cfg_name> realm <name> address <ocs_ipv4_or_ipv6_addr>
route-entry peer <gy_cfg_name>
exit
diameter endpoint <rf_cfg_name>
use-proxy
origin realm <realm_name>
origin host <name> address <rf_ipv4_address>
peer <rf_cfg_name> realm <name> address <ofcs_ipv4_or_ipv6_addr>
route-entry peer <rf_cfg_name>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <gx_interface_name> <aaa_context_name>
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <gy_interface_name> <aaa_context_name>
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <gz_interface_name> <aaa_context_name>
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <rf_interface_name> <aaa_context_name>
end
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Notes:
 The p-cscf table command under ims-auth-service can also specify an IPv4 address to the PCRF.
 The Gx interface IP address can also be specified as an IPv4 address using the ip address command.
 The Gy interface IP address can also be specified as an IPv4 address using the ip address command.
 The Rf interface IP address can also be specified as an IPv6 address using the ipv6 address command.
Configuring QCI-QoS Mapping
Use the following example to create and map QCI values to enforceable QoS parameters:
configure
qci-qos-mapping <name>
qci 1 user-datagram dscp-marking <hex>
qci 3 user-datagram dscp-marking <hex>
qci 9 user-datagram dscp-marking <hex>
exit
Notes:
 The SAEGW does not support non-standard QCI values. QCI values 1 through 9 are standard values and are
defined in 3GPP TS 23.203; the SAEGW supports these standard values.
 The above configuration only shows one keyword example. Refer to the QCI - QOS Mapping Configuration
Mode Commands chapter in the Command Line Interface Reference for more information on the qci command
and other supported keywords.
Verifying and Saving the Configuration
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
DHCP Service Configuration
The system can be configured to use the Dynamic Host Control Protocol (DHCP) to assign IP addresses for PDP
contexts. IP address assignment using DHCP is done using the following method, as configured within an APN:
DHCP-proxy: The system acts as a proxy for client (MS) and initiates the DHCP Discovery Request on behalf of client
(MS). Once it receives an allocated IP address from DHCP server in response to DHCP Discovery Request, it assigns
the received IP address to the MS. This allocated address must be matched with the an address configured in an IP
address pool on the system. This complete procedure is not visible to MS.
As the number of addresses in memory decreases, the system solicits additional addresses from the DHCP server. If the
number of addresses stored in memory rises above the configured limit, they are released back to the DHCP server.
There are parameters that must first be configured that specify the DHCP servers to communicate with and how the IP
address are handled. These parameters are configured as part of a DHCP service.
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Important: This section provides the minimum instruction set for configuring a DHCP service on system for
DHCP-based IP allocation. For more information on commands that configure additional DHCP server parameters and
working of these commands, refer to the DHCP Service Configuration Mode Commands chapter of Command Line
Interface Reference.
These instructions assume that you have already configured the system level configuration as described in System
Administration Guide and P-GW service as described in eGTP P-GW Configuration section of this chapter.
To configure the DHCP service:
Step 1
Create the DHCP service in system context and bind it by applying the example configuration in t he DHCP Service
Creation section.
Step 2
Configure the DHCP servers and minimum and maximum allowable lease times that are accepted in responses from
DHCP servers by applying the example configuration in the DHCP Server Parameter Configuration section.
Step 3
Verify your DHCP Service configuration by following the steps in the DHCP Service Configuration Verification
section.
Step 4
Save your configuration as described in the Verifying and Saving Your Configuration chapter.
DHCP Service Creation
Use the following example to create the DHCP service to support DHCP-based address assignment:
configure
context <dest_ctxt_name>
dhcp-service <dhcp_svc_name>
bind address <ip_address> [nexthop-forwarding-address <nexthop_ip_address>
[mpls-label input <in_mpls_label_value> output <out_mpls_label_value1>
[out_mpls_label_value2]]]
end
Notes:
 To ensure proper operation, DHCP functionality should be configured within a destination context.
 Optional keyword nexthop-forwarding-address <nexthop_ip_address > [mpls-label input
<in_mpls_label_value> output <out_mpls_label_value1 > [ out_mpls_label_value2 ]] applies
DHCP over MPLS traffic.
DHCP Server Parameter Configuration
Use the following example to configure the DHCP server parameters to support DHCP-based address assignment:
configure
context <dest_ctxt_name>
dhcp-service <dhcp_svc_name>
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dhcp server <ip_address> [priority <priority>
dhcp server selection-algorithm {first-server | round-robin}
lease-duration min <minimum_dur> max <max_dur>
dhcp deadtime <max_time>
dhcp detect-dead-server consecutive-failures <max_number>
max-retransmissions <max_number>
retransmission-timeout <dur_sec>
end
Notes:
 Multiple DHCP can be configured by entering dhcp server command multiple times. A maximum of 20
DHCP servers can be configured.
 The dhcp detect-dead-server command and max-retransmissions command work in conjunction with
each other.
 The retransmission-timeout command works in conjunction with max-retransmissions command.
DHCP Service Configuration Verification
Step 1
Verify that your DHCP servers configured properly by entering the following command in Exec Mode:
show dhcp service all
This command produces an output similar to that displayed below where DHCP name is dhcp1 :
Service name:
dhcp1
Context:
isp
Bind:
Done
Local IP Address:
150.150.150.150
Next Hop Address:
192.179.91.3
MPLS-label:
Input:
Output:
1566
1899
Service Status:
Started
Retransmission Timeout:
3000 (milli-secs)
Max Retransmissions:
2
Lease Time:
600 (secs)
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Minimum Lease Duration:
600 (secs)
Maximum Lease Duration:
86400 (secs)
DHCP Dead Time:
120 (secs)
DHCP Dead consecutive Failure:5
DHCP T1 Threshold Timer:
50
DHCP T2 Threshold Timer:
88
DHCP Client Identifier:
Not Used
DHCP Algorithm:
Round Robin
DHCP Servers configured:
Address: 150.150.150.150
Priority: 1
DHCP server rapid-commit: disabled
DHCP client rapid-commit: disabled
DHCP chaddr validation: enabled
Step 2
Verify the DHCP service status by entering the following command in Exec Mode:
show dhcp service status
DHCPv6 Service Configuration
The system can be configured to use the Dynamic Host Control Protocol (DHCP) for IPv6 to enable the DHCP servers
to pass the configuration parameters such as IPv6 network addresses to IPv6 nodes. DHCPv6 configuration is done
within an APN.
These instructions assume that you have already configured the system level configuration as described in System
Administration Guide and APN as described in P-GW PDN Context Configuration section of this chapter.
To configure the DHCPv6 service:
Step 1
Create the DHCPv6 service in system context and bind it by applying the example configuration in the DHCPv6 Service
Creation section.
Step 2
Configure the DHCPv6 server and other configurable values for Renew Time, Rebind Time, Preferred Lifetime, and
Valid Lifetime by applying the example configuration in the DHCPv6 Server Parameter Configuration section.
Step 3
Configure the DHCPv6 client and other configurable values for Maximum Retransmissions, Server Dead Tries, and
Server Resurrect Time by applying the example configuration in the DHCPv6 Client Parameter Configuration section.
Step 4
Configure the DHCPv6 profile by applying the example configuration in the DHCPv6 Profile Configuration section.
Step 5
Associate the DHCPv6 profile configuration with the APN by applying the example configuration in the Associate
DHCPv6 Configuration section.
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Step 6
Verify your DHCPv6 Service configuration by following the steps in the DHCPv6 Service Configuration Verification
section.
Step 7
Save your configuration as described in the Verifying and Saving Your Configuration chapter.
DHCPv6 Service Creation
Use the following example to create the DHCPv6 service to support DHCP-based address assignment:
configure
context <dest_ctxt_name>
dhcpv6-service <dhcpv6_svc_name>
bind address <ipv6_address> port <port>
end
Notes:
 To ensure proper operation, DHCPv6 functionality should be configured within a destination context.
 The Port specifies the listen port and is used to start the DHCPv6 server bound to it. It is optional and if
unspecified, the default port is 547.
DHCPv6 Server Parameter Configuration
Use the following example to configure the DHCPv6 server parameters to support DHCPv6-based address assignment:
configure
context <dest_ctxt_name>
dhcpv6-service <dhcpv6_svc_name>
dhcpv6-server
renew-time <renewal_time>
rebind-time <rebind_time>
preferred-lifetime <pref_lifetime>
valid-lifetime <valid_lifetime>
end
Notes:
 Multiple DHCP can be configured by entering dhcp server command multiple times. A maximum of 3
DHCPv6 servers can be configured.
 renew-time configures the renewal time for prefixes assigned by dhcp-service. Default is 900 seconds.
 rebind-time configures the rebind time for prefixes assigned by dhcp-service. Default is 900 seconds.
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 preferred-lifetime configures the preferred lifetime for prefixes assigned by dhcp-service. Default is 900
seconds.
 valid-lifetime configures the valid lifetime for prefixes assigned by dhcp-service. Default is 900 seconds.
DHCPv6 Client Parameter Configuration
Use the following example to configure the DHCPv6 client parameters to support DHCPv6-based address assignment:
configure
context <dest_ctxt_name>
dhcpv6-service <dhcpv6_svc_name>
dhcpv6-client
server-ipv6-address <ipv6_addr> port <port> priority <priority>
max-retransmissions <max_number>
server-dead-time <dead_time>
server-resurrect-time <revive_time>
end
Notes:
 DHCPv client configuration requires an IPv6 address, port, and priority. The port is used for communicating
with the DHCPv6 server. If not specified, default port 547 is used. The Priority parameter defines the priority
in which servers should be tried out.
 max-retransmissions configures the max retransmission that DHCPV6-CLIENT will make towards
DHCPV6-SERVER. Default is 20.
 server-dead-time : PDN DHCPV6-SERVER is considered to be dead if it does not respond after given tries
from client. Default is 5.
 server-resurrect-time : PDN DHCPV6-SERVER is considered alive after it has been dead for given
seconds. Default is 20.
DHCPv6 Profile Configuration
Use the following example to configure the DHCPv6 profile:
configure
context <dest_ctxt_name>
dhcp-server-profile <server_profile>
enable rapid-commit-dhcpv6
process dhcp-option-from { AAA | LOCAL | PDN-DHCP } priority <priority>
dhcpv6-server-preference <pref_value>
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enable dhcpv6-server-unicast
enable dhcpv6-server-reconf
exit
dhcp-client-profile <client_profile>
client-identifier { IMSI | MSISDN }
enable rapid-commit-dhcpv6
enable dhcp-message-spray
request dhcp-option dns-address
request dhcp-option netbios-server-address
request dhcp-option sip-server-address
end
Notes:
 dhcp-server-profile command creates a server profile and then enters the DHCP Server Profile
configuration mode.
 enable rapid-commit-dhcpv6 command enables rapid commit on the DHCPv6 server. By default it is
disabled. This is done to ensure that if there are multiple DHCPv6 servers in a network, with rapid-commitoption, they would all end up reserving resources for the UE.
 process dhcp-option-from command configures in what order the configuration options should be
processed for a given client request. For a given client configuration, values can be obtained from either AAA,
PDN-DHCP-SERVER, or LOCAL. By default, AAA is preferred over PDN-DHCP, which is preferred over
LOCAL configuration.
 dhcpv6-server-preference : According to RFC-3315, DHCPv6-CLIENT should wait for a specified
amount of time before considering responses to its queries from DHCPv6-SERVERS. If a server responds with
a preference value of 255, DHCPv6-CLIENT need not wait any longer. Default value is 0 and it may have any
configured integer between 1 and 255.
 enable dhcpv6-server-unicast command enables server-unicast option for DHCPv6. By default, it is
disabled.
 enable dhcpv6-server-reconf command configures support for reconfiguration messages from the server.
By default, it is disabled.
 dhcp-client-profile command creates a client profile and then enters the DHCP Client Profile
configuration mode.
 client identifier command configures the client-identifier, which is sent to the external DHCP server. By
default, IMSI is sent. Another available option is MSISDN.
 enable rapid-commit-dhcpv6 command configures the rapid commit for the client. By default, rapidcommit option is enabled for both DHCPv4 & DHCPv6.
 enable dhcp-message-spray command enables dhcp-client to spray a DHCP message to all configured
DHCP servers in the PDN. By default this is disabled. With Rapid-Commit, there can only be one server to
which this can be sent.
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 request dhcp-option command configures DHCP options which can be requested by the dhcp-client. It
supports the following options:
 dns-address
 netbios-server-address
 sip-server-address
Associate DHCPv6 Configuration
Use the following example to associate the DHCPv6 profile with an APN:
configure
context <dest_ctxt_name>
apn <apn_name>
dhcpv6 service-name <dhcpv6_svc_name> server-profile <server_profile> clientprofile <client_profile>
dhcpv6 ip-address-pool-name <dhcpv6_ip_pool>
dhcpv6 context-name <dest_ctxt>
exit
DHCPv6 Service Configuration Verification
Step 1
Verify that your DHCPv6 servers configured properly by entering the following command in Exec Mode:
show dhcpv6-service all
This command produces an output similar to that displayed below where DHCPv6 service name is dhcp6service :
Service name:
dhcpv6-service
Context:
A
Bind Address:
2092::192:90:92:40
Bind :
Done
Service Status:
Started
Server Dead Time:
120 (secs)
Server Dead consecutive Failure:5
Server Select Algorithm:
First Server
Server Renew Time:
400 (secs)
Server Rebind Time:
500 (secs)
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Server Preferred Life Time:
600 (secs)
Server Valid Life Time:
700 (secs)
Max Retransmissions:
3 (secs)
Server Dead Tries:
4 (secs)
Server Resurrect Time:
10 (secs)
ipv6_nd_flag:
O_FLAG
DHCPv6 Servers configured:
Address:
Step 2
2092::192:90:92:40 Priority: 1 enabled
Verify the DHCPv6 service status by entering the following command in Exec Mode:
show dhcpv6 status service dhcpv6_service_name
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Configuring Optional Features on the P-GW
The configuration examples in this section are optional and provided to cover the most common uses of the P-GW in a
live network. The intent of these examples is to provide a base configuration for testing.
The following optional configurations are provided in this section:
 Configuring ACL-based Node-to-Node IP Security on the S5 Interface
 Configuring APN as Emergency
 Configuring Dynamic Node-to-Node IP Security on the S5 Interface
 Configuring the GTP Echo Timer
 Configuring GTPP Offline Accounting on the P-GW
 Configuring Local QoS Policy
 Configuring X.509 Certificate-based Peer Authentication
Configuring ACL-based Node-to-Node IP Security on the S5 Interface
The configuration example in this section creates an IKEv2/IPSec ACL-based node-to-node tunnel endpoint on the S5
interface.
Important: Use of the IP Security feature requires that a valid license key be installed. Contact your local Sales
or Support representative for information on how to obtain a license.
The following configuration examples are included in this section:
 Creating and Configuring a Crypto Access Control List
 Creating and Configuring an IPSec Transform Set
 Creating and Configuring an IKEv2 Transform Set
 Creating and Configuring a Crypto Map
Creating and Configuring a Crypto Access Control List
The following example configures a crypto ACL (Access Control List), which defines the matching criteria used for
routing subscriber data packets over an IPSec tunnel:
configure
context <saegw_context_name> -noconfirm
ip access-list <acl_name>
permit tcp host <source_host_address> host <dest_host_address>
end
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Notes:
 The permit command in this example routes IPv4 traffic from the server with the specified source host IPv4
address to the server with the specified destination host IPv4 address.
Creating and Configuring an IPSec Transform Set
The following example configures an IPSec transform set, which is used to define the security association that
determines the protocols used to protect the data on the interface:
configure
context <saegw_context_name> -noconfirm
ipsec transform-set <ipsec_transform-set_name>
encryption aes-cbc-128
group none
hmac sha1-96
mode tunnel
end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IPSec transform sets configured on the system.
 The group none command specifies that no crypto strength is included and that Perfect Forward Secrecy is
disabled. This is the default setting for IPSec transform sets configured on the system.
 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for IPSec
transform sets configured on the system.
 The mode tunnel command specifies that the entire packet is to be encapsulated by the IPSec header including
the IP header. This is the default setting for IPSec transform sets configured on the system.
Creating and Configuring an IKEv2 Transform Set
The following example configures an IKEv2 transform set:
configure
context <saegw_context_name> -noconfirm
ikev2-ikesa transform-set <ikev2_transform-set_name>
encryption aes-cbc-128
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group 2
hmac sha1-96
lifetime <sec>
prf sha1
end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IKEv2 transform sets configured on the system.
 The group 2 command specifies the Diffie-Hellman algorithm as Group 2, indicating medium security. The
Diffie-Hellman algorithm controls the strength of the crypto exponentials. This is the default setting for IKEv2
transform sets configured on the system.
 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for
IKEv2 transform sets configured on the system.
 The lifetime command configures the time the security key is allowed to exist, in seconds.
 The prf command configures the IKE Pseudo-random Function which produces a string of bits that cannot be
distinguished from a random bit string without knowledge of the secret key. The sha1 keyword uses a 160-bit
secret key to produce a 160-bit authenticator value. This is the default setting for IKEv2 transform sets
configured on the system.
Creating and Configuring a Crypto Map
The following example configures an IKEv2 crypto map:
configure
context <saegw_context_name>
crypto map <crypto_map_name> ikev2-ipv4
match address <acl_name>
peer <ipv4_address>
authentication local pre-shared-key key <text>
authentication remote pre-shared-key key <text>
ikev2-ikesa transform-set list <name1> . . . name6>
payload <name> match ipv4
lifetime <seconds>
ipsec transform-set list <name1> . . . <name4>
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exit
exit
interface <s5_intf_name>
ip address <ipv4_address>
crypto-map <crypto_map_name>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <s5_intf_name> <saegw_context_name>
end
Notes:
 The type of crypto map used in this example is IKEv2/IPv4 for IPv4 addressing. An IKEv2/IPv6 crypto map can
also be used for IPv6 addressing.
 The ipsec transform-set list command specifies up to four IPSec transform sets.
Configuring APN as Emergency
The configuration example in this section configures an emergency APN for VoLTE based E911 support.
In APN Configuration Mode, specify the name of the emergency APN and set the emergency inactivity timeout as
follows. You may also configure the P-CSCF FQDN server name for the APN.
configure
context <saegw_context_name> -noconfirm
apn <name>
emergency-apn
timeout emergency-inactivity <seconds>
p-cscf fqdn <fqdn>
end
Notes:
 By default, an APN is assumed to be non-emergency.
 The timeout emergency-inactivity command specifies the timeout duration, in seconds, to check
inactivity on the emergency session. <seconds > must be an integer value from 1 through 3600.
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 By default, emergency inactivity timeout is disabled (0).
 The p-cscf fqdn command configures the P-CSCF FQDN server name for the APN. <fqdn > must be a string
from 1 to 256 characters in length.
 P-CSCF FQDN has more significance than CLI-configured P-CSCF IPv4 and IPv6 addresses.
Configuring Dynamic Node-to-Node IP Security on the S5 Interface
The configuration example in this section creates an IPSec/IKEv2 dynamic node-to-node tunnel endpoint on the S5
interface.
Important: Use of the IP Security feature requires that a valid license key be installed. Contact your local Sales
or Support representative for information on how to obtain a license.
The following configuration examples are included in this section:
 Creating and Configuring an IPSec Transform Set
 Creating and Configuring an IKEv2 Transform Set
 Creating and Configuring a Crypto Template
 Binding the S5 IP Address to the Crypto Template
Creating and Configuring an IPSec Transform Set
The following example configures an IPSec transform set, which is used to define the security association that
determines the protocols used to protect the data on the interface:
configure
context <saegw_context_name> -noconfirm
ipsec transform-set <ipsec_transform-set_name>
encryption aes-cbc-128
group none
hmac sha1-96
mode tunnel
end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IPSec transform sets configured on the system.
 The group none command specifies that no crypto strength is included and that Perfect Forward Secrecy is
disabled. This is the default setting for IPSec transform sets configured on the system.
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 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for IPSec
transform sets configured on the system.
 The mode tunnel command specifies that the entire packet is to be encapsulated by the IPSec header, including
the IP header. This is the default setting for IPSec transform sets configured on the system.
Creating and Configuring an IKEv2 Transform Set
The following example configures an IKEv2 transform set:
configure
context <saegw_context_name> -noconfirm
ikev2-ikesa transform-set <ikev2_transform-set_name>
encryption aes-cbc-128
group 2
hmac sha1-96
lifetime <sec>
prf sha1
end
Notes:
 The encryption algorithm, aes-cbc-128, or Advanced Encryption Standard Cipher Block Chaining, is the
default algorithm for IKEv2 transform sets configured on the system.
 The group 2 command specifies the Diffie-Hellman algorithm as Group 2, indicating medium security. The
Diffie-Hellman algorithm controls the strength of the crypto exponentials. This is the default setting for IKEv2
transform sets configured on the system.
 The hmac command configures the Encapsulating Security Payload (ESP) integrity algorithm. The sha1-96
keyword uses a 160-bit secret key to produce a 160-bit authenticator value. This is the default setting for
IKEv2 transform sets configured on the system.
 The lifetime command configures the time the security key is allowed to exist, in seconds.
 The prf command configures the IKE Pseudo-random Function, which produces a string of bits that cannot be
distinguished from a random bit string without knowledge of the secret key. The sha1 keyword uses a 160-bit
secret key to produce a 160-bit authenticator value. This is the default setting for IKEv2 transform sets
configured on the system.
Creating and Configuring a Crypto Template
The following example configures an IKEv2 crypto template:
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configure
context <saegw_context_name> -noconfirm
crypto template <crypto_template_name> ikev2-dynamic
ikev2-ikesa transform-set list <name1> . . . <name6>
ikev2-ikesa rekey
payload <name> match childsa match ipv4
ipsec transform-set list <name1> . . . <name4>
rekey
end
Notes:
 The ikev2-ikesa transform-set list command specifies up to six IKEv2 transform sets.
 The ipsec transform-set list command specifies up to four IPSec transform sets.
Binding the S5 IP Address to the Crypto Template
The following example configures the binding of the S5 interface to the crypto template:
configure
context <saegw_context_name> -noconfirm
gtpu-service <gtpu_ingress_service_name>
bind ipv4-address <s5_interface_ip_address> crypto-template
<sgw_s5_crypto_template>
exit
egtp-service <egtp_ingress_service_name>
interface-type interface-pgw-ingress
associate gtpu-service <gtpu_ingress_service_name>
gtpc bind ipv4-address <s5_interface_ip_address>
exit
pgw-service <pgw_service_name> -noconfirm
plmn id mcc <id> mnc <id> primary
associate egtp-service <egtp_ingress_service_name>
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end
Notes:
 The bind command in the GTP-U and eGTP service configuration can also be specified as an IPv6 address
using the ipv6-address command.
Configuring the GTP Echo Timer
The GTP echo timer on the ASR5x00 P-GW can be configured to support two different types of path management:
default and dynamic. This timer can be configured on the GTP-C and/or the GTP-U channels.
Default GTP Echo Timer Configuration
The following examples describe the configuration of the default eGTP-C and GTP-U interface echo timers:
eGTP-C
configure
configure
context <context_name>
egtp-service <egtp_service_name>
gtpc echo-interval <seconds>
gtpc echo-retransmission-timeout <seconds>
gtpc max-retransmissions <num>
end
Notes:
 The following diagram describes a failure and recovery scenario using default settings of the three gtpc
commands in the example above:
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 The multiplier (x2) is system-coded and cannot be configured.
GTP-U
configure
configure
context <context_name>
gtpu-service <gtpu_service_name>
echo-interval <seconds>
echo-retransmission-timeout <seconds>
max-retransmissions <num>
end
Notes:
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 The following diagram describes a failure and recovery scenario using default settings of the three GTP-U
commands in the example above:
 The multiplier (x2) is system-coded and cannot be configured.
Dynamic GTP Echo Timer Configuration
The following examples describe the configuration of the dynamic eGTP-C and GTP-U interface echo timers:
eGTP-C
configure
configure
context <context_name>
egtp-service <egtp_service_name>
gtpc echo-interval <seconds> dynamic smooth-factor <multiplier>
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gtpc echo-retransmission-timeout <seconds>
gtpc max-retransmissions <num>
end
Notes:
 The following diagram describes a failure and recovery scenario using default settings of the three gtpc
commandsin the example above and an example round trip timer (RTT) of six seconds:
 The multiplier (x2) and the 100 second maximum are system-coded and cannot be configured.
GTP-U
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configure
configure
context <context_name>
gtpu-service <gtpu_service_name>
echo-interval <seconds> dynamic smooth-factor <multiplier>
echo-retransmission-timeout <seconds>
max-retransmissions <num>
end
Notes:
 The following diagram describes a failure and recovery scenario using default settings of the three gtpc
commands in the example above and an example round trip timer (RTT) of six seconds:
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 The multiplier (x2) and the 100 second maximum are system-coded and cannot be configured.
Configuring GTPP Offline Accounting on the P-GW
By default the P-GW service supports GTPP accounting. To provide GTPP offline charging, configure the P-GW with
the example parameters below:
configure
gtpp single-source
context <saegw_context_name>
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subscriber default
accounting mode gtpp
exit
gtpp group default
gtpp charging-agent address <gz_ipv4_address>
gtpp echo-interval <seconds>
gtpp attribute diagnostics
gtpp attribute local-record-sequence-number
gtpp attribute node-id-suffix <string>
gtpp dictionary <name>
gtpp server <ipv4_address> priority <num>
gtpp server <ipv4_address> priority <num> node-alive enable
exit
policy accounting <gz_policy_name>
accounting-level {type}
operator-string <string>
cc profile <index> buckets <num>
cc profile <index> interval <seconds>
cc profile <index> volume total <octets>
exit
exit
context <saegw_context_name>
apn apn
associate accounting-policy <gz_policy_name>
exit
interface <gz_interface_name>
ip address <address>
exit
exit
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port ethernet <slot_number/port_number>
no shutdown
bind interface <gz_interface_name> <saegw_context_name>
end
Notes:
 gtpp single-source is enabled to allow the system to generate requests to the accounting server using a
single UDP port (by way of a AAA proxy function) rather than each AAA manager generating requests on
unique UDP ports.
 gtpp is the default option for the accounting mode command.
 An accounting mode configured for the call-control profile will override this setting.
 accounting-level types are: flow, PDN, PDN-QCI, QCI, and subscriber. Refer to the Accounting Profile
Configuration Mode Commands chapter in the Command Line Interface Reference for more information on
this command.
Configuring Local QoS Policy
The configuration examples in this section creates a local QoS policy. A local QoS policy service can be used to control
different aspects of a session, such as QoS, data usage, subscription profiles, or server usage, by means of locally
defined policies.
Important: Local QoS Policy is a licensed feature and requires the purchase of the Local Policy Decision Engine
feature license to enable. it.
The following configuration examples are included in this section:
 Creating and Configuring a Local QoS Policy
 Binding a Local QoS Policy
 Verifying Local QoS Policy
Creating and Configuring a Local QoS Policy
The following configuration example enables a local QoS policy on the P-GW:
configure
local-policy-service <name> -noconfirm
ruledef <ruledef_name> -noconfirm
condition priority <priority> <variable> match <string_value>
condition priority <priority> <variable> match <int_value>
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condition priority <priority> <variable> nomatch <regex>
exit
actiondef <actiondef_name> -noconfirm
action priority <priority> <action_name> <arguments>
action priority <priority> <action_name> <arguments>
exit
actiondef <actiondef_name> -noconfirm
action priority <priority> <action_name> <arguments>
action priority <priority> <action_name> <arguments>
exit
eventbase <eventbase_name> -noconfirm
rule priority <priority> event <list_of_events> ruledef <ruledef_name> actiondef
<actiondef_name>
end
Notes:
 A maximum of 16 local QoS policy services are supported.
 A maximum 256 ruledefs are suggested in a local QoS policy service for performance reasons.
 The condition command can be entered multiple times to configure multiple conditions for a ruledef. The
conditions are examined in priority order until a match is found and the corresponding condition is applied.
 A maximum of 256 actiondefs are suggested in a local QoS policy service for performance reasons.
 The action command can be entered multiple times to configure multiple actions for an actiondef. The actions
are examined in priority order until a match is found and the corresponding action is applied.
 Currently, only one eventbase is supported and must be named “default”.
 The rule command can be entered multiple times to configure multiple rules for an eventbase.
 A maximum of 256 rules are suggested in an eventbase for performance reasons.
 Rules are executed in priority order, and if the rule is matched the action specified in the actiondef is executed. If
an event qualifier is associated with a rule, the rule is matched only for that specific event. If a qualifier of
continue is present at the end of the rule, the subsequent rules are also matched; otherwise, rule evaluation is
terminated on first match.
Binding a Local QoS Policy
The following configuration example binds the previously configured local QoS policy:
configure
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context <saegw_context_name> -noconfirm
apn <name>
ims-auth-service <local-policy-service name>
end
Notes:
 A maximum of 16 authorization services can be configured globally in the system. There is also a system limit
for the maximum number of total configured services.
Verifying Local QoS Policy
The following configuration example verifies if local QoS service is enforced:
logging filter active facility local -policy level debug
logging active
show local-policy statistics all
Notes:
 Please take extreme caution not to use logging feature in console port and in production nodes.
Configuring X.509 Certificate-based Peer Authentication
The configuration example in this section enables X.509 certificate-based peer authentication, which can be used as the
authentication method for IP Security on the P-GW.
Important: Use of the IP Security feature requires that a valid license key be installed. Contact your local Sales
or Support representative for information on how to obtain a license.
The following configuration example enables X.509 certificate-based peer authentication on the P-GW.
In Global Configuration Mode, specify the name of the X.509 certificate and CA certificate, as follows:
configure
certificate name <cert_name> pem url <cert_pem_url> private-key pem url
<private_key_url>
ca-certificate name <ca_cert_name> pem url <ca_cert_url>
end
Notes:
 The certificate name and ca-certificate list ca-cert-name commands specify the X.509
certificate and CA certificate to be used.
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 The PEM-formatted data for the certificate and CA certificate can be specified, or the information can be read
from a file via a specified URL as shown in this example.
When creating the crypto template for IPSec in Context Configuration Mode, bind the X.509 certificate and CA
certificate to the crypto template and enable X.509 certificate-based peer authentication for the local and remote nodes,
as follows:
configure
context <saegw_context_name> -noconfirm
crypto template <crypto_template_name> ikev2-dynamic
certificate name <cert_name>
ca-certificate list ca-cert-name <ca_cert_name>
authentication local certificate
authentication remote certificate
end
Notes:
 A maximum of 16 certificates and 16 CA certificates are supported per system. One certificate is supported per
service, and a maximum of four CA certificates can be bound to one crypto template.
 The certificate name and ca-certificate list ca-cert-name commands bind the certificate and CA
certificate to the crypto template.
 The authentication local certificate and authentication remote certificate commands
enable X.509 certificate-based peer authentication for the local and remote nodes.
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Chapter 3
Network Mobility (NEMO)
This chapter describes the system’s support for NEMO and explains how it is configured. The product administration
guides provide examples and procedures for configuration of basic services on the system. It is recommended that you
select the configuration example that best meets your service model and configure the required elements for that model,
as described in the Cisco ASR 5x00 Packet Data Network Gateway Administration Guide, before using the procedures
in this chapter.
This chapter includes the following sections:
 NEMO Overview
 NEMO Configuration
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NEMO Overview
When enabled through a feature license key, the system includes NEMO support for a Mobile IPv4 Network Mobility
(NEMO-HA) on the P-GW platform to terminate Mobile IPv4 based NEMO connections from Mobile Routers (MRs)
that attach to an Enterprise PDN. The NEMO functionality allows bi-directional communication that is applicationagnostic between users behind the MR and users or resources on Fixed Network sites.
The same NEMO4G-HA service and its bound Loopback IP address supports NEMO connections whose underlying
PDN connection comes through GTP S5 (4G access) or PMIPv6 S2a (eHRPD access).
The following figure shows a high-level view of LTE NEMOv4 Architecture.
Figure 27.
NEMO Overview
Use Cases
The following use cases are supported by NEMO in LTE:
1. Stationary - Applications, like branch offices, with a mobile router that does not require mobility.
2. Nomadic - Applications that use a mobile router that does not move while in service, but that may be moved to a
different location and brought back on service (e.g. a kiosk showing up in a mall one day and in a different
location the next day or month).
3. Moveable - Applications that need to maintain Dynamic Mobile Network Routing (DMNR) service operational
while moving and crossing PDSN boundaries, such as public safety vehicles. Service continuity is handled by
the mobility protocols (Mobile IP in 3G and GTP in LTE).
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Features and Benefits
The system supports the usage of dynamically learned, overlapping customer prefixes. These prefixes are advertised via
BGP.
MIPv4-based NEMO Control Plane
The following figure shows a high-level view of the NEMO control plane.
Figure 28.
NEMO Control Plane
NEMO includes the following features:
 Collocated-Care-of-Address mode
The Cisco NEMO MR is expected to use the Collocated-Care-of-Address mode to establish a NEMO MIPv4
session with NEMO4G-HA and as one of the IP endpoints of the NEMO GRE Tunnel for the transport of user
traffic.
 MR-HADDR
NEMO4G-HA supports a potential “dummy” MR-HADDR address that would be configured in every MR
within the same Enterprise or across all served Enterprises (same IP address).
 Dynamic advertisement of WAN-IP Pools and learned LAN prefixes
eBGP is used to advertise the Enterprise WAN-IP Pools and the LAN prefixes learned via NEMO for the
associated Enterprise.
 N-MHAE credentials
NEMO4G-HA supports local authentication for the NEMO MIPv4 RRQ based on preconfigured N-MHAESPI/KEY values on a per Enterprise basis (one unique set for all MRs belonging to the same Enterprise) or on a
global basis (one unique set for all Enterprises).
 LAN prefixes
 NEMO4G-HA accepts a minimum of zero LAN prefixes and a maximum of eight prefixes per mobile
router. Anything beyond eight prefixes shall be silently discarded.
 NEMO4G-HA supports any prefix length (including /32).
 NEMO4G-HA supports dynamic prefix updates.
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 NEMO4G-HA removes from the associated Enterprise VRF routing table any prefixes that are
not included in a scheduled or ad-hoc NEMO MIPv4 re-registration request from a given MR
(assuming these were present in a previous NEMO MIPv4 RRQ). E-PGW shall update the
external VRF router of the removal of such prefixes on the next eBGP update.
 NEMO4G-HA accepts and installs any new prefixes that are included in a scheduled or ad-hoc
NEMO MIPv4 re-registration request to the associated Enterprise VRF routing table, as long
as it doesn't exceed the maximum number of supported prefixes per MR (up to eight). EPGW shall update the external VRF router of the newly installed prefixes on the next eBGP
update. NEMO4G-HA shall accept NEMO MIPv4 RRQs that do not include any prefixes in
the first initial RRQ and it shall accept prefixes advertised in subsequent RRQs.
 In case of a prefix whose IP address or mask is changed on the MR, the MR will remove the
old IP address/mask and add the new IP address/mask prefix in a scheduled or ad -hoc NEMO
MIPv4 re-registration request and NEMO4G-HA shall remove the old route and add the new
route corresponding to the new prefix to the Enterprise VRF routing table
 Overlapping IP addressing
NEMO4G-HA supports private and overlapping IP addressing across multiple Enterprises for the WAN IP
pools, MR-HADDR, and LAN prefixes.
NEMO MR Authorization
NEMO4G-HA authorizes a NEMO MIPv4 session only if a NEMO permission has been assigned to the underlying
PDN connection. NEMO permission should be assigned to the underlying PDN connection via either local
configuration (APN parameter) or based on a NEMO permission AVP assigned by the 3GPP AAA during the PDN
authorization. For local configuration, a new APN parameter is supported to enable NEMO permission at the APN/PDN
level within the P-GW service.
MIPv4 NEMO Protocol
NEMO4G-HA processes a Mobile IPv4 NEMO Registration Request (RRQ) received from the MR NEMO client.
NEMO4G-HA processes the first of three Cisco-specific MIPv4 Extensions of type Normal Vendor/Org Specific
Extension (NVSE) that are included in the MIPv4 NEMO RRQ. The three Cisco-specific NVSEs are placed after the
MIPv4 “Identification” field and before the mandatory MIPv4 “Mobile-Home-Authentication-Extension.” NEMO4GHA accepts the LAN prefixes (up to eight) encoded in the first Cisco-specific NVSE (vendor-type = 9). NEMO4G-HA
is not expected to process the other two Cisco-specific NVSEs with vendor-type = 49, which carry the Internal Interface
ID of the MR's Roaming Interface and the MR's Roaming Interface Bandwidth in Kbps, respectively.
Cisco-specific NVSEs follow RFC 3025 “Mobile IP Vendor/Organization Specific Extensions.”
GRE Encapsulation
User traffic shall be encapsulated over a GRE tunnel between the MR NEMO client and NEMO4G-HA. The IP
endpoints of the GRE tunnel shall be the IPv4 assigned to the MR modem during the Enterprise PDN connection setup
and the IPv4 address of the NEMO4G-HA service on the E-PGW.
NEMO4G-HA shall remove the GRE encapsulation before it forwards the outbound traffic towards the Enterprise VPN
via the associated SGi VLAN interface. Inbound traffic received through the same SGi VLAN interface shall be
encapsulated into a GRE tunnel before it's passed to the E-PGW service for forwarding to the MR through the proper
GTP/PMIP tunnel.
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Session Interactions
The following session interaction scenarios are supported between NEMO and the underlying PDN connection made
over eHRPD or LTE access.
In the following circumstances, NEMO4G-HA shall withdraw the associated prefix routes from the Enterprise VRF
routing table, update the eBGP neighbors and free up all internal resources allocated for the underlying PDN connection
and NEMO session:
 When the eHRPD terminates the underlying PDN connection (PPP-VSNCP-Term-Req sent to MR and PMIPBU with lifetime = 0 sent to E-PGW).
 When the MR terminates the PPP/PDN connection when accessing the network via eHRPD.
 After an eUTRAN (LTE) detach procedure initiated by the MR or MME.
NEMO4G-HA shall not be able to process any NEMO MIPv4 RRQs if there's no underlying PDN connection
associated to those RRQs (PMIPv6 or GTP). In other words, NEMO MIPv4 RRQs can be accepted and processed only
if an Enterprise PDN connection has been established with E-PGW by the mobile router.
NEMO4G-HA shall silently ignore NEMO MIPv4 RRQs if the underlying PDN connection associated to each of those
RRQs does not have the NEMO permission indication. This applies to both eHRPD and LTE access.
NEMO4G-HA shall forward (not drop) user data using MIP or GRE tunneling (UDP/434 or IP Protocol/47,
respectively) to the external enterprise VRF if such data is not destined to the NEMO4G-HA IP address. This applies to
PDN connections that have or do not have the NEMO Permission indication. This shall also apply to both eHRPD and
LTE access.
Any failure on either the authentication or authorize of a NEMO MIPv4 session shall not affect the underlying PDN
connection established between the mobile router and the E-PGW via eHRPD or LTE. For example, if the security
credentials do not match between the MR NEMO client and NEMO4G-HA, NEMO4G-HA can reject the NEMO
MIPv4 RRQ, but the associated PDN connection shall not be terminated.
NEMO Session Timers
NEMO4G-HA uses the registration lifetime value locally configured, even though MR's may use the maximum possible
value (65534).
NEMO4G-HA can process ad-hoc NEMO RRQ messages.
Enterprise-wide Route Limit Control
NEMO4G-HA supports a control mechanism to limit the maximum number of prefixes/routes that a given enterprise
can register, including the pools for WAN IP assignments.
When the maximum number of routes is reached, a syslog message is generated. Once the number of routes goes under
the limit, a syslog message is generated for notification.
Forced Fragmentation
E-PGW forces IP packet fragmentation even for IP packets with the DF-bit set.
Redundancy/Reliability
The LTE NEMO solution supports intra-chassis Session Redundancy (SR) and Inter-Chassis Session Redundancy
(ICSR) functionalities.
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LTE NEMO Call Flow
The following figure describes the call flow of the NEMOv4 solution.
Figure 29.
NEMOv4 Call Flow
1. The Cisco MR eHWIC establishes first a connection to the IMS PDN to register to the LTE Network. The
eHWIC's User Id must be properly provisioned on the HSS/SPR to be successfully authenticated.
2. After the Cisco MR eHWIC registers with the LTE network and establishes a connection to the IMS PDN, then
it connects to the appropriate Enterprise PDN based on the locally configured Enterprise APN.
 During the PDN authorization procedure using S6b, the 3GPP AAA assigns a NEMO permission via
AVP. The AVP is also be available as an APN parameter on the E-PGW to allow NEMO service at
the PDN/Enterprise level.
 E-PGW assigns the MR eHWIC an IPv4 address from the Enterprise IPv4 pool assigned during PDN
authentication.
 E-PGW creates the proper flows internally to forward packets to the corresponding VRF external to the
E-PGW platform using the IPv4 pool configuration on the egress context.
 The MR eHWIC passed on the assigned IPv4 address to the NEMO application (also called WAN-IPv4
address).
3. The MR NEMO application initiates a Mobile IPv4 registration request (RRQ) using the following local
configuration and the IPv4 address assigned to the eHWIC during the Enterprise PDN attach procedure
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(referred to as WAN-IP). The NEMO MIPv4 RRQ will be carried as a regular user packet over the mobility
connection, either GTP in LTE and PPP/PMIPv6 in eHRPD. The NEMO MIPv4 RRQ includes the following
key parameters:
 CCOA - IPv4 address assigned to the eHWIC modem during the Enterprise PDN connection setup
(WAN-IP). The MR NEMO application will use the CCOA/WAN-IP address as the source of all
NEMO packets sent to NEMO4G-HA (control and tunneled user traffic).
 MR-HADDR - Mandatory IPv4 address preconfigured in the MR NEMO application. MR-HADDR is
normally used as the source of all NEMO control packets sent to the NEMO4G-HA. However, the
MR NEMO application will use the CCOA as the source for all NEMO packets (control and tunneled
user traffic). Therefore, NEMO4G-HA will ignore the preconfigured MR-HADDR included in the
RRQ, but it will still include it in the NEMO MIPv4 RRP.
 Home Agent Address - Preconfigured IPv4 address that the MR NEMO application uses as the
destination for all NEMO control and GRE tunneled user data (NEMO4G-HA's IPv4 Address).
 Explicit LAN Prefixes - Locally attached IPv4 networks preconfigured on the MR NEMO application.
LAN prefixes will be encoded in the same Cisco NVSE extension currently used in the NEMO
solution for 3G. The Cisco NVSE included in the NEMOv4 MIP RRQ is in the form of a TLV.
 N-MHAE - Mandatory NEMO MN-HA Authentication Extension that includes the SPI and the
authenticator computed using a pre-shared Key. Both SPI and Key are preconfigured in the MR
NEMO application as well.
 NEMO-Tunnel flags such as, but not limited to, “Reverse Tunnel,” “Direct Termination,” “Tunnel
Encapsulation” = GRE.
4. NEMO4G-HA sends a MIP registration response (RRP) back to the MR after it performs the following tasks:
 Authenticate the RRQ using the N-MHAE information included in the RRQ.
 Authorize the NEMO service based on the NEMO permission attribute assigned to the associated
Enterprise PDN connection.
 Accept the prefixes advertised in the Cisco NVSE extension included in the NEMO MIPv4 RRQ.
 The learned prefixes will have to adhere to the current rules of valid pool routes. The minimum
valid mask length is /13 and pool routes can not include 0.0.0.0 or 255.255.255.255.
 NEMO4G-HA will accept a minimum of 0 prefixes and a maximum of 8 prefixes. Anything
beyond 8 prefixes will be silently discarded.
 NEMO4G-HA will also check that the new resultant enterprise route count (total number of
VRF routes) do not exceed the route limit potentially configured for the given enterprise. If
the preconfigured route limit is exceeded, then NEMO4G-HA will reject the NEMO MIP
RRQ. Otherwise, NEMO4G-HA will install the accepted prefixes in the internal VRF
associated with the Enterprise PDN.
 eBGP would then propagate the new NEMO routes to the external VRF as part of the next
BGP update.
5. Upon receiving the NEMO MIP RRP, the MR will install a default route (0.0.0.0/0) in its routing table to route
all traffic through the LTE connection.
 Outbound packets are encapsulated over GRE using the CCOA/WAN-IP address as the source and the
NEMO4G-HA-Service IPv4 address as the destination of the tunnel.
 Inbound packets are encapsulated over GRE as well from the NEMO4G-HA to the MR NEMO
application. The source of the GRE tunnel is the NEMO4G-HA-Service IPv4 address and the
destination is the CCOA/WAN-IP address.
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Engineering Rules
 Up to 100 virtual routing tables per context. This allows up to 100 BGP-VPNs per context.
 Up to 5k host routes spread across multiple VRFs per BGP process. Limited to 6000 pool routes per chassis.
 Up to 1024 VRFs per chassis.
Supported Standards
 IETF RFC 3025 (February 2001) “Mobile IP Vendor/Organization Specific Extensions”
 IETF RFC 1191 (November 1990) “Path MTU Discovery”
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NEMO Configuration
Important: Commands used in the configuration samples in this section provide base functionality to the extent
that the most common or likely commands and/or keyword options are presented. In many cases, other optional
commands and/or keyword options are available. Refer to the Command Line Interface Reference for complete
information regarding all commands.
To configure the system for NEMO:
1. Create a VRF on the router and assign a VRF-ID by applying the example configuration in the Create a VRF
section.
2. Set the neighbors and address family to exchange routing information with a peer router by applying the example
configuration in the Set Neighbors and Address Family section.
3. Redistribute connected routes between routing domains by applying the example configuration in the
Redistribute Connected Routes section.
4. Allow the P-GW to use the NEMO service by applying the example in the Configure and Enable NEMO in APN
Profile section.
5. Create a NEMO HA by applying the example in the Create a NEMO HA section.
6. Save your configuration to flash memory, an external memory device, and/or a network location using the Exec
mode command save configuration . For additional information on how to verify and save configuration
files, refer to the System Administration Guide and the Command Line Interface Reference.
Sample Configuration
context egress
interface corp1-outbound
ip address 192.168.1.1 255.255.255.0
exit
ip vrf corp1
ip pool corp1-test 10.1.1.1 255.255.255.0 private vrf corp1
nexthop-forwarding-address 192.168.1.2 overlap vlanid 50
router bgp 100
address-family ipv4 vrfcorp1
neighbor192.168.1.2 remote-as 300
neighbor 192.168.1.2 allow-default-vrf-connection
redistribute connected
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exit
exit
context pgw
apn nemo.corp1.com
permission nemo
ip context-name egress
ip address pool name corp1_nemo_pool
exit
exit
context ingress
interface corp1-inbound
ip address 192.168.1.1 255.255.255.0
exit
ha-service nemo
mn-ha-spi spi-number 100 encrypted secret 01abd002c82b4a2c
authentication mn-aaa noauth
encapsulation allow keyless-gre
bind address 38.0.0.2
end
Create a VRF
Use this example to first create a VRF on the router and assign a VRF-ID.
configure
context <context_name> -noconfirm
ip vrf <vrf_name>
ip pool <pool_name> <pool_address> private vrf <vrf_name>
nexthop-forwarding-address <ip_address> overlap vlanid <vlan_id>
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Set Neighbors and Address Family
Use this example to set the neighbors and address family to exchange routing information with a peer router.
configure
context <context_name>
ip vrf <vrf_name>
router bgp <as_number>
ip vrf <vrf_name>
neighbor <ip_address> remote-as <AS_num>
address-family <type>
neighbor <ip_address> activate
end
Redistribute Connected Routes
Use this example to redistribute connected routes between routing domains.
configure
context <context_name>
ip vrf <vrf_name>
router bgp <as_number>
ip vrf <vrf_name>
address-family <type> vrf <vrf_name>
redistribute connected
exit
redistribute connected
end
Configure and Enable NEMO in APN Profile
Use this example to configure and enable NEMO in an APN profile.
configure
context <context_name>
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apn <apn_name>
permission nemo
ip context-name <name>
ip address pool name <pool_nme>
end
Create a NEMO HA
Use this example to create a NEMO HA.
configure
context <context_name>
ha-service <ha_service_name>
mn-ha-spi spi-number <number> encrypted secret <enc_secret>
authentication mn-aaa noauth
encapsulation allow keyless-gre
bind address <ip_address>
end
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Chapter 4
Operator Policy
The proprietary concept of an operator policy, originally architected for the exclusive use of an SGSN, is non -standard
and currently unique to the ASR 5x00. This optional feature empowers the carrier with flexible control to manage
functions that are not typically used in all applications and to determine the granularity of the implementation of any
operator policy: to groups of incoming calls or to simply one single incoming call.
The following products support the use of the operator policy feature:
 MME (Mobility Management Entity - LTE)
 SGSN (Serving GPRS Support Node - 2G/3G/LTE)
 S-GW (Serving Gateway - LTE)
This document includes the following information:
 What Operator Policy Can Do
 The Operator Policy Feature in Detail
 Call Control Profile
 APN Profile
 IMEI-Profile (SGSN only)
 APN Remap Table
 Operator Policies
 IMSI Ranges
 How It Works
 Operator Policy Configuration
 Verifying the Feature Configuration
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What Operator Policy Can Do
Operator policy enables the operator to specify a policy with rules governing the services, facilities and p rivileges
available to subscribers.
A Look at Operator Policy on an SGSN
The following is only a sampling of what working operator policies can control on an SGSN:
 APN information included in call activation messages are sometimes damaged, misspelled, missing. In such
cases, the calls are rejected. The operator can ensure calls aren't rejected and configure a range of methods for
handling APNs, including converting incoming APNs to preferred APNs and this control can be used in a
focused fashion or defined to cover ranges of subscribers.
 In another example, it is not unusual for a blanket configuration to be implemented for all subscriber profiles
stored in the HLR. This results in a waste of resources, such as the allocation of the default highest QoS setting
for all subscribers. An operator policy provides the opportunity to address such issues by allowing fine-tuning
of certain aspects of profiles fetched from HLRs and, if desired, overwrite QoS settings received from HLR.
A Look at Operator Policy on an S-GW
The S-GW operator policy provides mechanisms to fine tune the behavior for subsets of subscribers. It also can be used
to control the behavior of visiting subscribers in roaming scenarios by enforcing roaming agreement s and providing a
measure of local protection against foreign subscribers.
The S-GW uses operator policy in the SGW service configuration to control the accounting mode. The default
accounting mode is GTTP, but RADIUS/Diameter and none are options. The accounting mode value from the call
control profile overrides the value configured in SGW service. If the accounting context is not configured in the call
control profile, it is taken from SGW service. If the SGW service does not have the relevant configurati on, the current
context or default GTPP group is assumed.
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The Operator Policy Feature in Detail ▀
The Operator Policy Feature in Detail
This flexible feature provides the operator with a range of control to manage the services, facilities and privileges
available to subscribers.
Operator policy definitions can depend on factors such as (but not limited to):
 roaming agreements between operators,
 subscription restrictions for visiting or roaming subscribers,
 provisioning of defaults to override standard behavior.
These policies can override standard behaviors and provide mechanisms for an operator to circumvent the limitations of
other infrastructure elements such as DNS servers and HLRs in 2G/3G networks.
By configuring the various components of an operator policy, the operator fine-tunes any desired restrictions or
limitations needed to control call handling and this can be done for a group of callers within a defined IMSI range or per
subscriber.
Re-Usable Components - Besides enhancing operator control via configuration, the operator policy feature minimizes
configuration by drastically reducing the number of configuration lines needed. Operator policy maximizes
configurations by breaking them into the following reusable components that can be shared across IMSI ranges or
subscribers:
 call control profiles
 IMEI profiles (SGSN only)
 APN profiles
 APN remap tables
 operator policies
 IMSI ranges
Each of these components is configured via a separate configuration mode accessed through the Global Configuration
mode.
Call Control Profile
A call control profile can be used by the operator to fine-tune desired functions, restrictions, requirements, and/or
limitations needed for call management on a per-subscriber basis or for groups of callers across IMSI ranges. For
example:
 setting access restriction cause codes for rejection messages
 enabling/disabling authentication for various functions such as attach and service requests
 enabling/disabling ciphering, encryption, and/or integrity algorithms
 enabling/disabling of packet temporary mobile subscriber identity (P-TMSI) signature allocation (SGSN only)
 enabling/disabling of zone code checking
 allocation/retention priority override behavior (SGSN only)
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 enabling/disabling inter-RAT, 3G location area, and 4G tracking area handover restriction lists (MME and SGW only)
 setting maximum bearers and PDNs per subscriber (MME and S-GW only)
Call control profiles are configured with commands in the Call Control Profile configuration mode. A single call control
profile can be associated with multiple operator policies
For planning purposes, based on the system configuration, type of packet services cards, type of network (2G, 3G, 4G,
LTE), and/or application configuration (single, combo, dual access), the following call control profile configuration
rules should be considered:
 1 (only one) - call control profile can be associated with an operator policy
 1000 - maximum number of call control profiles per system (e.g., an SGSN).
 15 - maximum number of equivalent PLMNs for 2G and 3G per call control profile
 15 - maximum number of equivalent PLMNs for 2G per ccprofile.
 15 - maximum number of supported equivalent PLMNs for 3G per ccprofile.
 256 - maximum number of static SGSN addresses supported per PLMN
 5 - maximum number of location area code lists supported per call control profile.
 100 - maximum number of LACs per location area code list supported per call control profile.
 unlimited number of zone code lists can be configured per call control profile.
 100 - maximum number of LACs allowed per zone code list per call control profile.
 2 - maximum number of integrity algorithms for 3G per call control profile.
 3 - maximum number of encryption algorithms for 3G per call control profile.
APN Profile
An APN profile groups a set of access point name (APN)-specific parameters that may be applicable to one or more
APNs. When a subscriber requests an APN that has been identified in a selected operator policy, the parameter values
configured in the associated APN profile will be applied.
For example:
 enable/disable a direct tunnel (DT) per APN. (SGSN)
 define charging characters for calls associated with a specific APN.
 identify a specific GGSN to be used for calls associated with a specific APN (SGSN).
 define various quality of service (QoS) parameters to be applied to calls associated with a specific APN.
 restrict or allow PDP context activation on the basis of access type for calls associated with a specific APN.
APN profiles are configured with commands in the APN Profile configuration mode. A single APN profile can be
associated with multiple operator policies.
For planning purposes, based on the system configuration, type of packet p rocessing cards and 2G, 3G, 4G, and/or dual
access, the following APN profile configuration rules should be considered:
 50 - maximum number of APN profiles that can be associated with an operator policy.
 1000 - maximum number of APN profiles per system (e.g., an SGSN).
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 116 - maximum gateway addresses (GGSN addresses) that can be defined in a single APN profile.
IMEI-Profile (SGSN only)
The IMEI is a unique international mobile equipment identity number assigned by the manufacturer that is used by the
network to identify valid devices. The IMEI has no relationship to the subscriber.
An IMEI profile group is a set of device-specific parameters that control SGSN behavior when one of various types of
Requests is received from a UE within a specified IMEI range. These parameters control:
 Blacklisting devices
 Identifying a particular GGSN to be used for connections for specified devices
 Enabling/disabling direct tunnels to be used by devices
IMEI profiles are configured with commands in the IMEI Profile configuration mode. A single IMEI profile can be
associated with multiple operator policies.
For planning purposes, based on the system configuration, type of packet processing cards, type of network (2G, 3G,
4G, LTE), and/or application configuration (single, combo, dual access), the following IMEI profile configuration rules
should be considered:
 10 - maximum number of IMEI ranges that can be associated with an operator policy.
 1000 - maximum number of IMEI profiles per system (such as an SGSN).
APN Remap Table
APN remap tables allow an operator to override an APN specified by a user, or the APN selected during the normal
APN selection procedure, as specified by 3GPP TS 23.060. This atypical level of control enables operators to deal with
situations such as:
 An APN is provided in the Activation Request that does not match with any of the subscribed APNs; either a
different APN was entered or the APN could have been misspelled. In such situations, the SGSN would reject
the Activation Request. It is possible to correct the APN, creating a valid name so that the Activation Request
is not rejected.
 In some cases, an operator might want to force certain devices/users to use a specific APN. For example, all
iPhone4 users may need to be directed to a specific APN. In such situations, the operator needs to be able to
override the selected APN.
An APN remap table group is a set of APN-handling configurations that may be applicable to one or more subscribers.
When a subscriber requests an APN that has been identified in a selected operator policy, the parameter values
configured in the associated APN remap table will be applied. For example, an APN remap table allows configuration
of the following:
 APN aliasing - maps incoming APN to a different APN based on partial string match (MME and SGSN) or
matching charging characteristic (MME and SGSN).
 Wildcard APN - allows APN to be provided by the SGSN when wildcard subscription is present and the user has
not requested an APN.
 Default APN - allows a configured default APN to be used when the requested APN cannot be used – for
example, the APN is not part of the HLR subscription.
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APN remap tables are configured with commands in the APN Remap Table configuration mode. A single APN remap
table can be associated with multiple operator policies, but an operator policy can only be associated with a sing le APN
remap table.
For planning purposes, based on the system configuration, type of packet processing cards, type of network (2G, 3G,
4G, LTE), and/or application configuration (single, combo, dual access), the following APN remap table configuration
rules should be considered:
 1 – maximum number of APN remap tables that can be associated with an operator policy.
 1000 – maximum number of APN remap tables per system (such as an SGSN).
 100 – maximum remap entries per APN remap table.
Operator Policies
The profiles and tables are created and defined within their own configuration modes to generate sets of rules and
instructions that can be reused and assigned to multiple policies. An operator policy binds the various configuration
components together. It associates APNs, with APN profiles, with an APN remap table, with a call control profile,
and/or an IMEI profile (SGSN only) and associates all the components with filtering ranges of IMSIs.
In this manner, an operator policy manages the application of rules governing the services, facilities, and privileges
available to subscribers.
Operator policies are configured and the associations are defined via the commands in the Operator Policy configuration
mode.
The IMSI ranges are configured with the command in the SGSN-Global configuration mode.
For planning purposes, based on the system configuration, type of packet processing cards, type of network (2G, 3G,
4G, LTE), and/or application configuration (single, combo, dual access), the following operator policy configuration
rules should be considered:
 1 – maximum number of call control profiles associated with a single operator policy.
 1 – maximum number of APN remap tables associated with a single operator policy.
 10 – maximum number of IMEI profiles associated with a single operator policy (SGSN only)
 50 – maximum number of APN profiles associated with a single operator policy.
 1000 – maximum number of operator policies per system (e.g., an SGSN); this number includes the single
default operator policy.
 1000 – maximum number of IMSI ranges defined per system (e.g., an SGSN).
Important: SGSN operator policy configurations created with software releases prior to Release 11.0 are not
forward compatible. Such configurations can be converted to enable them to work with an SGSN running Release 11.0
or higher. Your Cisco Account Representative can accomplish this conversion for you.
IMSI Ranges
Ranges of international mobile subscriber identity (IMSI) numbers, the unique number identifying a subscriber, are
associated with the operator policies and used as the initial filter to determine whether or not any operator policy would
be applied to a call. The range configurations are defined by the MNC, MCC, a range of MSINs, and optionally the
PLMN ID. The IMSI ranges must be associated with a specific operator policy.
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IMSI ranges are defined differently for each product supporting the operator policy feature.
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How It Works
The specific operator policy is selected on the basis of the subscriber’s IMSI at attach time, and optionally the PLMN ID
selected by the subscriber or the RAN node's PLMN ID. Unique, non-overlapping, IMSI + PLMN-ID ranges create call
filters that distinguish among the configured operator policies.
The following flowchart maps out the logic applied for the selection of an operator policy:
Figure 30.
Operator Policy Selection Logic
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Operator Policy Configuration
This section provides a high-level series of steps and the associated configuration examples to configure an operator
policy. By configuring an operator policy, the operator fine-tunes any desired restrictions or limitations needed to
control call handling per subscriber or for a group of callers within a defined IMSI range.
Most of the operator policy configuration components are common across the range of products supporting operator
policy. Differences will be noted as they are encountered below.
Important: This section provides a minimum instruction set to implement operator policy. For this feature to be
operational, you must first have completed the system-level configuration as described in the System Administration
Guide and the service configuration described in your product’s administration guide.
The components can be configured in any order. This example begins with the call control profile:
Step 1
Create and configure a call control profile, by applying the example configuration presented in the Call Control Profile
Configuration section.
Step 2
Create and configure an APN profile, by applying the example configuration presented in the APN Profile
Configuration section.
Important: It is not necessary to configure both an APN profile and an IMEI profile. You can
associate either type of profile with a policy. It is also possible to associate one or more APN profiles with an
IMEI profile for an operator policy (SGSN only).
Step 3
Create and configure an IMEI profile by applying the example configuration presented in the IMEI Profile
Configuration section (SGSN only).
Step 4
Create and configure an APN remap table by applying the example configuration presented in the APN Remap Table
Configuration section.
Step 5
Create and configure an operator policy by applying the example configuration presented in the Operator Policy
Configuration section.
Step 6
Configure an IMSI range by selecting and applying the appropriate product-specific example configuration presented in
the IMSI Range Configuration sections below.
Step 7
Associate the configured operator policy components with each other and a network service by applying the example
configuration in the Operator Policy Component Associations section.
Step 8
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide .
Step 9
Verify the configuration for each component separately by following the instructions provided in the Verifying the
Feature Configuration section of this chapter.
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Call Control Profile Configuration
This section provides the configuration example to create a call control profile and enter the configuration mode.
Use the call control profile commands to define call handling rules that will be applied via an operator policy. Only one
call control profile can be associated with an operator policy, so it is necessary to use (and repeat as necessary) the range
of commands in this mode to ensure call-handling is sufficiently managed.
Configuring the Call Control Profile for an SGSN
The example below includes some of the more commonly configured call control profile parameters with sample
variables that you will replace with your own values.
configure
call-control-profile <profile_name>>
attach allow access-type umts location-area-list instance <list_id>
authenticate attach
location-area-list instance <instance> area-code <area_code>
sgsn-number <E164_number>
end
Note:
 Refer to the Call Control Profile Configuration Mode chapter in the Command Line Interface Reference for
command details and variable options.
 This profile will only become valid when it is associated with an operator policy.
Configuring the Call Control Profile for an MME or S-GW
The example below includes some of the more commonly configured call control profile parameters with sample
variables that you will replace with your own values.
configure
call-control-profile <profile_name>>
associate hss-peer-service <service_name> s6a-interface
attach imei-query-type imei verify-equipment-identity
authenticate attach
dns-pgw context <mme_context_name>
dns-sgw context <mme_context_name>
end
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Note:
 Refer to the Call Control Profile Configuration Mode chapter in the Command Line Interface Reference for
command details and variable options.
 This profile will only become valid when it is associated with an operator p olicy.
APN Profile Configuration
This section provides the configuration example to create an APN profile and enter the apn-profile configuration mode.
Use the apn-profile commands to define how calls are to be handled when the requests include an APN. More than
one APN profile can be associated with an operator policy.
The example below includes some of the more commonly configured profile parameters with sample variables that you
will replace with your own values.
configure
apn-profile <profile_name>
gateway-address 123.123.123.1 priority <1> (SGSN only)
direct-tunnel not-permitted-by-ggsn (SGSN only)
idle-mode-acl ipv4 access-group station7 (S-GW only)
end
Note:
 All of the parameter defining commands in this mode are product-specific. Refer to the APN Profile
Configuration Mode chapter in the Command Line Interface Reference for command details and variable
options.
 This profile will only become valid when it is associated with an operator policy.
IMEI Profile Configuration - SGSN only
This section provides the configuration example to create an IMEI profile and enter the imei -profile configuration mode.
Use the imei-profile commands to define how calls are to be handled when the requests include an IMEI in the
defined IMEI range. More than one IMEI profile can be associated with an operator policy.
The example below includes some of the more commonly configured profile parameters with sample variables that you
will replace with your own values.
configure
imei-profile <profile_name>
ggsn-address 211.211.123.3
direct-tunnel not-permitted-by-ggsn (SGSN only)
associate apn-remap-table remap1
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end
Note:
 It is optional to configure an IMEI profile. An operator policy can include IMEI profiles and/or APN p rofiles.
 This profile will only become valid when it is associated with an operator policy.
APN Remap Table Configuration
This section provides the configuration example to create an APN remap table and enter the apn-remap-table
configuration mode.
Use the apn-remap-table commands to define how APNs are to be handled when the requests either do or do not
include an APN.
The example below includes some of the more commonly configured profile parameters with sample variables that you
will replace with your own values.
configure
apn-remap-table <table_name>
apn-selection-default first-in-subscription
wildcard-apn pdp-type ipv4 network-identifier <apn_net_id>
blank-apn network-identifier <apn_net_id> (SGSN only)
end
Note:
 The apn-selection-default first-in-subscription command is used for APN redirection to provide
“guaranteed connection” in instances where the UE-requested APN does not match the default APN or is
missing completely. In this example, the first APN matching the PDP type in the subscription is used. The firstin-selection keyword is an MME feature only.
 Some of the commands represented in the example above are common and some are product-specific. Refer to
the APN-Remap-Table Configuration Mode chapter in the Command Line Interface Reference for command
details and variable options.
 This profile will only become valid when it is associated with an operator policy.
Operator Policy Configuration
This section provides the configuration example to create an operator policy and enter the operator policy configuration
mode.
Use the commands in this mode to associate profiles with the policy, to define and associate APNs with the policy, and
to define and associate IMEI ranges. Note: IMEI ranges are supported for SGSN only.
The example below includes sample variable that you will replace with your own values.
configure
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operator-policy <policy_name>
associate call-control-profile <profile_name>
apn network-identifier <apn-net-id_1> apn-profile <apn_profile_name_1>
apn network-identifier <apn-net-id_2> apn-profile <apn_profile_name_1>
imei range <imei_number> to <imei_number> imei-profile name <profile_name>
associate apn-remap-table <table_name>
end
Note:
 Refer to the Operator-Policy Configuration Mode chapter in the Command Line Interface Reference for
command details and variable options.
 This policy will only become valid when it is associated with one or more IMSI ranges (SGSN) or subscriber
maps (MME and S-GW).
IMSI Range Configuration
This section provides IMSI range configuration examples for each of the products that support operator policy
functionality.
Configuring IMSI Ranges on the MME or S-GW
IMSI ranges on an MME or S-GW are configured in the Subscriber Map Configuration Mode. Use the following
example to configure IMSI ranges on an MME or S-GW:
configure
subscriber-map <name>
lte-policy
precedence <number> match-criteria imsi mcc <mcc_number> mnc <mnc_number> msin
first <start_range> last <end_range> operator-policy-name <policy_name>
end
Note:
 The precedence number specifies the order in which the subscriber map is used. 1 has the highest precedence.
 The operator policy name identifies the operator policy that will be used for subscribers that match t he IMSI
criteria and fall into the MSIN range.
Configuring IMSI Ranges on the SGSN
The example below is specific to the SGSN and includes sample variables that you will replace with your own values.
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configure
sgsn-global
imsi-range mcc 311 mnc 411 operator-policy oppolicy1
imsi-range mcc 312 mnc 412 operator-policy oppolicy2
imsi-range mcc 313 mnc 413 operator-policy oppolicy3
imsi-range mcc 314 mnc 414 operator-policy oppolicy4
imsi-range mcc 315 mnc 415 operator-policy oppolicy5
end
Note:
 Operator policies are not valid until IMSI ranges are associated with them.
Associating Operator Policy Components on the MME
After configuring the various components of an operator policy, each component must be associated with the other
components and, ultimately, with a network service.
The MME service associates itself with a subscriber map. From the subscriber map, which also contains the IMSI
ranges, operator policies are accessed. From the operator policy, APN remap tables and call control profiles are
accessed.
Use the following example to configure operator policy component associations:
configure
operator-policy <name>
associate apn-remap-table <table_name>
associate call-control-profile <profile_name>
exit
lte-policy
subscriber-map <name>
precedence match-criteria all operator-policy-name <policy_name>
exit
exit
context <mme_context_name>
mme-service <mme_svc_name>
associate subscriber-map <name>
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end
Notes:
 The precedence command in the subscriber map mode has other match-criteria types. The all type is
used in this example.
Configuring Accounting Mode for S-GW
The accounting mode command configures the mode to be used for the S-GW service for accounting, either GTPP
(default), RADIUS/Diameter, or None.
Use the following example to change the S-GW accounting mode from GTPP (the default) to RADIUS/Diameter:
configure
context <sgw_context_name>
sgw-service <sgw_srv_name>
accounting mode radius-diameter
end
Notes:
 An accounting mode configured for the call control profile will override this setting.
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Verifying the Feature Configuration
This section explains how to display the configurations after saving them in a .cfg file as described in the System
Administration Guide .
Important: All commands listed here are under Exec mode. Not all commands are available on all platforms.
Step 1
Verify that the operator policy has been created and that required profiles have been associated and configured properly
by entering the following command in Exec Mode:
show operator-policy full name oppolicy1
The output of this command displays the entire configuration for the operator policy configuration.
[local]asr5x00# show operator-policy full name oppolicy1
Operator Policy Name = oppolicy1
Call Control Profile Name
: ccprofile1
Validity
: Valid
APN Remap Table Name
: remap1
Validity
IMEI Range 711919739
IMEI Profile Name
: Valid
to
711919777
: imeiprof1
Include/Exclude
: Include
Validity
: Valid
APN NI homers1
APN Profile Name
Validity
: apn-profile1
: Valid
Note:
 If the profile name is shown as “Valid”, the profile has actually been created and associated with the policy. If
the Profile name is shown as “Invalid”, the profile has not been created/configured.
 If there is a valid call control profile, a valid APN profile and/or valid IMEI profile, and a valid APN remap
table, the operator policy is valid and complete if the IMSI range has been defined and associated.
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Chapter 5
S-GW Event Reporting
This appendix describes the record content and trigger mechanisms for S-GW event reporting. When enabled the S-GW
write a record of session events and sends the resulting event files to an external file server for processing. Each event is
sent to the server within 60 seconds of its occurrence.
The following topics are covered in this appendix:
 Event Record Triggers
 Event Record Elements
 Active-to-Idle Transitions
 3GPP 29.274 Cause Codes
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Event Record Triggers
When properly configured, the S-GW creates and sends a record in CSV format as the session events listed below occur.

ID 1: Session Creation

ID 2: Session Deletion

ID 3: Bearer Creation

ID 4: Bearer Deletion

ID 5: Bearer Modification


suppress intra-system handover

configurable enable active to idle transition event reporting
ID 6: Bearer Update
The following guidelines apply to the above session events:

A session refers to a PDN connection and the default bearer associated with it.

Bearer events refer to dedicated bearers that have been created/deleted/updated/modified.

Bearer modifications that are intra-S-GW and intra-MME are not be reported.

Bearers and sessions that fail to setup are reported once in a session/bearer creation record with the result code set t o
failure.
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Event Record Elements ▀
Event Record Elements
Each event record includes the information documented in the table below in comma separated value (CSV) ASCII
format. The elements are listed in the order in which they will appear. All record elements are not available for all event
triggers. If a record element cannot be populated due to incomplete information, th e element is omitted and the comma
separation maintained.
The following guidelines apply to record elements:
 Byte/packet counters shall not be sent in session or bearer creation messages
 Byte/packet counters include packets and bytes sent or received since the last record created for that session or
bearer.
 The S-GW will attempt to populate all record elements. Values that are unavailable will not be populated.
Table 18. S-GWEvent Record Elements
Event
Number
Description
Format
Size
(bytes)
Applicable Event
Numbers
1
Event identity (ID 1 – ID 6)
Integer [1-6]
1
All
2
Event Result (3GPP 29.274 Cause
Code)
Integer [1-255]
3
All
3
IMSI
Integer (15 digits)
15
All
4
IMEISV
Integer (16 digits)
16
All
5
Start Time (GMT)
MM/DD/YYYYHH:MM:SS:_MS(millisecond accuracy)
18
All
6
End Time (GMT)
MM/DD/YYYYHH:MM:SS:_MS(millisecond accuracy)
18
2, 4
7
Protocol (GTPv2)
String
5
All
8
Disconnect code (ASR 5x00)
Integer [1-999]
3
All
9
Trigger Event (3GPP 29.274
request cause code)
Integer [1-15]
3
All
10
Origination Node
String (CLLI)
10
All
11
Origination Node Type
String (SGW|HSGW|PGW|...)
3
All
12
EPS Bearer ID(Default)
Integer [0-15]
1 or 2
All
13
APN Name
String
34 to
255
All
14
PGW IP Address
IPv4 or IPv6 address
7 to 55
All
15
UE IPv4 Address
IPv4 address
7 to 15
All
16
UE IPv6 Address
IPv6 address
3 to 55
All
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Event
Number
Description
Format
Size
(bytes)
Applicable Event
Numbers
17
Uplink AMBR
Integer (0-4000000000)
1 to 10
All
18
Downlink AMBR
Integer (0-4000000000)
1 to 10
All
19
TAI - MCC/MNC/TAC
String (MCC;MNC;TAC)
14
All
20
Cell ID (ECI)
String (28 bits)
8
All
21
EPS Bearer ID (dedicated)
Integer (0-15)
1 or 2
21
22
Result Code (success/fail)
0=fail 1=success
1
All
23
QCI
Integer[1-255]
1 to 3
All
24
Uplink MBR (bps)
Integer (0-4000000000)
1 to 10
All
25
Downlink MBR (bps)
Integer (0-4000000000)
1 to 10
All
26
Uplink GBR (bps)
Integer (0-4000000000)
1 to 10
All
27
Downlink GBR (bps)
Integer (0-4000000000)
1 to 10
All
28
Downlink Packets Sent (interval)
Integer (0-4000000000)
1 to 10
2, 4, 5, 6
29
Downlink Bytes Sent (interval)
Integer (0-500000000000)
1 to 12
2, 4, 5, 6
30
Downlink Packets Dropped
(interval)
Integer (0-500000000000)
1 to 12
2, 4, 5, 6
31
Uplink Packets Sent (interval)
Integer (0-500000000000)
1 to 12
2, 4, 5, 6
32
Uplink Bytes Sent (interval)
Integer (0-500000000000)
1 to 12
2, 4, 5, 6
33
Uplink Packets Dropped (interval)
Integer (0-4000000000)
1 to 10
2, 4, 5, 6
34
MME S11 IP Address
IPv4 or IPv6 address
7 to 55
All
35
S1u IP Addressof eNodeB
IPv4 or IPv6 address
7 to 55
All
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Active-to-Idle Transitions
This figure and table below describes how active-to-idle transitions generate event records.
Table 19.
Subscriber-initiated Attach (initial) Call Flow Description
Step
Description
1
UE becomes Active (via UE or NW initiated service request)
2
Session becomes idle.
3
S-GW acknowledges idle session.
4
Bearer modification event record is created, with the following fields:
 Start Time: Use the start time of the idle-to-active transition

End Time: Use the timestamp of the idle time

Bytes up/Bytes down: Amount of data sent between transitions

Packets up/Packets down: Number of packets sent between transitions
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▀ 3GPP 29.274 Cause Codes
3GPP 29.274 Cause Codes
The following table lists some of the most commonly implemented cause codes identified in Record Element 2 – Event
Result.
Table 20. 3GPP 29.274 Cause Codes
Cause Value
Meaning
Request
2
Local Detach
3
Complete
4
RAT changed from 3GPP to Non-3GPP
5
ISR deactivation
6
Error Indication received from RNC/eNodeB
Accept
16
Request accepted
17
Request accepted partially
18
New PDN type due to network preference
19
New PDN type due to single address bearer only
Reject
64
Context Not Found
65
Invalid Message Format
66
Version not supported by next peer
67
Invalid length
68
Service not supported
69
Mandatory IE incorrect
70
Mandatory IE missing
71
Reserved
72
System failure
73
No resources available
74
Semantic error in the TFT operation
75
Syntactic error in the TFT operation
76
Semantic errors in packet filter(s)
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S-GW Event Reporting
3GPP 29.274 Cause Codes ▀
Cause Value
Meaning
77
Syntactic errors in packet filter(s)
78
Missing or unknown APN
79
Unexpected repeated IE
80
GRE key not found
81
Relocation failure
82
Denied in RAT
83
Preferred PDN type not supported
84
All dynamic addresses are occupied
85
UE context without TFT already activated
86
Protocol type not supported
87
UE not responding
88
UE refuses
89
Service denied
90
Unable to page UE
91
No memory available
92
User authentication failed
93
APN access denied - no subscription
94
Request rejected
95
P-TMSI Signature mismatch
96
IMSI not known
97
Semantic error in the TAD operation
98
Syntactic error in the TAD operation
99
Reserved Message Value Received
100
Remote peer not responding
101
Collision with network initiated request
102
Unable to page UE due to Suspension
103
Conditional IE missing
104
APN Restriction type Incompatible with currently active PDN connection
105
Invalid overall length of the triggered response message and a piggybacked initial message
106
Data forwarding not supported
107
Invalid reply from remote peer
116 to 239
Spare. This value range is reserved for Cause values in rejection response message.
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▀ 3GPP 29.274 Cause Codes
Cause Value
Meaning
Sub-Causes
NO_INFORMATION
ABORTED_BY_SESSION_DELETION
NO_RESPONSE_FROM_MME
INTERNALLY_TRIGGERED
BEARERS_IN_MULTIPLE_PDN_CONNECTIONS
EXPECTED_BEARERS_MISSING_IN_MESSAGE
UNEXPECTED_BEARERS_PRESENT_IN_MESSAGE
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Chapter 6
Configuring Subscriber Session Tracing
This chapter provides information on subscriber session trace functionality to allow an operator to trace subscriber
activity at various points in the network and at various level of details in EPS network. The product Administration
Guides provide examples and procedures for configuration of basic services on the system. It is recommended that you
select the configuration example that best meets your service model, and configure the required elements for that model,
as described in the respective product Administration Guide, before using the procedures in this chapter.
This chapter discusses following topics for feature support of Subscriber Session Tracing in LTE service:
 Introduction
 Supported Standards
 Subscriber Session Tracing Functional Description
 Subscriber Session Trace Configuration
 Verifying Your Configuration
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▀ Introduction
Introduction
The Subscriber Level Trace provides a 3GPP standards-based session-level trace function for call debugging and testing
new functions and access terminals in an LTE environment.
In general, the Session Trace capability records and forwards all control activity for the monitored subscriber on the
monitored interfaces. This is typically all the signaling and authentication/subscriber services messages that flow when a
UE connects to the access network.
The EPC network entities like MME, S-GW, P-GW support 3GPP standards based session level trace capabilities to
monitor all call control events on the respective monitored interfaces including S6a, S1 -MME and S11 on MME, S5,
S8, S11 at S-GW and S5 and S8 on P-GW. The trace can be initiated using multiple methods:
 Management initiation via direct CLI configuration
 Management initiation at HSS with trace activation via authentication response messages over S6a reference
interface
 Signaling based activation through signaling from subscriber access terminal
Important: Once the trace is provisioned it can be provisioned through the access cloud via various signaling
interfaces.
The session level trace function consists of trace activation followed by triggers. The time between the two events is
where the EPC network element buffers the trace activation instructions for the provisioned subscriber in memory using
camp-on monitoring. Trace files for active calls are buffered as XML files using non-volatile memory on the local dual
redundant hard drives on the chassis. The Trace Depth defines the granularity of data to be traced. Six levels are defined
including Maximum, Minimum and Medium with ability to configure additional levels based on vendor extensions.
Important: Only Maximum Trace Depth is supported in the current release.
The following figure shows a high-level overview of the session-trace functionality and deployment scenario:
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Introduction ▀
Figure 31.
Session Trace Function and Interfaces
All call control activity for active and recorded sessions is sent to an off-line Trace Collection Entity (TCE) using a
standards-based XML format over a FTP or secure FTP (SFTP) connection.
Note: In the current release the IPv4 interfaces are used to provide connectivity to the TCE. Trace activation is based on
IMSI or IMEI.
Supported Functions
This section provides the list of supported functionality of this feature support:
 Support to trace the control flow through the access network.
 Trace of specific subscriber identified by IMSI
 Trace of UE identified by IMEI(SV)
 Ability to specify specific functional entities and interfaces where tracing should occur.
 Scalability and capacity
 Support up to 32 simultaneous session traces per NE
 Capacity to activate/deactivate TBD trace sessions per second
 Each NE can buffer TBD bytes of trace data locally
 Statistics and State Support
 Session Trace Details
 Management and Signaling-based activation models
 Trace Parameter Propagation
 Trace Scope (EPS Only)
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▀ Introduction
 MME: S1, S3, S6a, S10, S11
 S-GW: S4, S5, S8, S11, Gxc
 PDN-GW: S2a, S2b, S2c, S5, S6b, Gx, S8, SGi
 Trace Depth: Maximum, Minimum, Medium (with or without vendor extension)
 XML Encoding of Data as per 3GPP standard 3GPP TS 32.422 V8.6.0 (2009-09)
 Trace Collection Entity (TCE) Support
 Active pushing of files to the TCE
 Passive pulling of files by the TCE
 1 TCE support per context
 Trace Session Recovery after Failure of Session Manager
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Supported Standards ▀
Supported Standards
Support for the following standards and requests for comments (RFCs) have been added with this interface su pport:
 3GPP TS 32.421 V8.5.0 (2009-06): 3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects; Telecommunication management; Subscriber and equipment trace: Trace concepts and
requirements (Release 8)
 3GPP TS 32.422 V8.6.0 (2009-09): 3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects; Telecommunication management; Subscriber and equipment trace; Trace control and
configuration management (Release 8)
 3GPP TS 32.423 V8.2.0 (2009-09): 3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects; Telecommunication management; Subscriber and equipment trace: Trace data definition
and management (Release 8)
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▀ Subscriber Session Trace Functional Description
Subscriber Session Trace Functional Description
This section describes the various functionality involved in tracing of subscriber session on EPC nodes:
Operation
The session trace functionality is separated into two steps - activation and trigger.
Before tracing can begin, it must be activated. Activation is done either via management request or when a UE initiates
a signaled connection. After activation, tracing actually begins when it is triggered (defin ed by a set of trigger events).
Trace Session
A trace session is the time between trace activation and trace de-activation. It defines the state of a trace session,
including all user profile configuration, monitoring points, and start/stop triggers. It is uniquely identified by a Trace
Reference.
The Trace Reference id is composed of the MCC (3 digits) + the MNC (3 digits) + the trace Id (3 byte octet string).
Trace Recording Session
A trace recording session is a time period in which activity is actually being recorded and traceable data is being
forwarded to the TCE. A trace recording session is initiated when a start trigger event occurs and continues until the
stop trigger event occurs and is uniquely identified by a Trace Recording Session Reference.
Network Element (NE)
Network elements are the functional component to facilitate subscriber session trace in mobile network.
The term network element refers to a functional component that has standard interfaces in and out of it. It is typically
shown as a stand-alone AGW. Examples of NEs are the MME, S-GW, and P-GW.
Currently, subscriber session trace is not supported for co-located network elements in the EPC network.
Activation
Activation of a trace is similar whether it be via the management interface or via a signaling interface. In both cases, a
trace session state block is allocated which stores all configuration and state information for the trace session. In
addition, a (S)FTP connection to the TCE is established if one does not already exist (if this is the first trace session
established, odds are there will not be a (S)FTP connection already established to the TCE).
If the session to be traced is already active, tracing may begin immediately. Otherwise, tracing activity concludes until
the start trigger occurs (typically when the subscriber or UE under trace initiates a connection). A failure to activate a
trace (due to max exceeded or some other failure reason) results in a notification being sent to the TCE indicating the
failure.
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Subscriber Session Trace Functional Description ▀
Management Activation
With a management-initiated activation, the WEM sends an activation request directly to the NE where the trace is to be
initiated. The NE establishes the trace session and waits for a triggering event to start actively tracing. Depending upon
the configuration of the trace session, the trace activation may be propagated to other NEs.
Signaling Activation
With a signaling based activation, the trace session is indicated to the NE across a signaling interface via a trace
invocation message. This message can either be piggybacked with an existing bearer setup message (in order to trace all
control messages) or by sending a separate trace invocation message (if the user is already active).
Start Trigger
A trace recording session starts upon reception of one of the configured start triggers. Once the start trigger is received,
the NE generates a Trace Recording Session Reference (unique to the NE) and begins to collect and forward trace
information on the session to the TCE.
List of trigger events are listed in 3GPP standard 3GPP TS 32.422 V8.6.0 (2009 -09).
Deactivation
Deactivation of a Trace Session is similar whether it was management or signaling activated. In either case, a
deactivation request is received by the NE that contains a valid trace reference results in the de-allocation of the trace
session state block and a flushing of any pending trace data. In addition, if this is the last trace session to a particular
TCE, the (S)FTP connection to the TCE is released after the last trace file is successfully transferred to the TCE.
Stop Trigger
A trace recording session ends upon the reception of one of the configured stop triggers. Once the stop trigger is
received, the NE will terminate the active recording session and attempt to send any pending trace data to the TCE. The
list of triggering events can be found in 3GPP standard 3GPP TS 32.422 V8.6.0 (2009 -09).
Data Collection and Reporting
Subscriber session trace functionality supprots data collection and reporting system to provide historical usage adn event
analysis.
All data collected by the NE is formatted into standard XML file format and forwarded to the TCE via (S)FTP. The
specific format of the data is defined in 3GPP standard 3GPP TS 32.423 V8.2.0 (2009-09)
Trace Depth
The Trace Depth defines what data is to be traced. There are six depths defined: Maximum, Minimum, and Medium all
having with and without vendor extension flavors. The maximum level of detail results in the entire control message
getting traced and forwarded to the TCE. The medium and minimum define varying subsets of the control messages
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▀ Subscriber Session Trace Functional Description
(specific decoded IEs) to be traced and forwarded. The contents and definition of the medium and minimum trace can
be found in 3GPP standard 3GPP TS 32.423 V8.2.0 (2009-09).
Important: Only Maximum Trace Depth is supported in the current release.
Trace Scope
The Trace Scope defines what NEs and what interfaces have the tracing capabilities enabled on them. This is actually a
specific list of NE types and interfaces provided in the trace session configuration by the operator (either directly via a
management interface or indirectly via a signaling interface).
Network Element Details
Trace functionality for each of the specific network elements supported by this functionality are described in this
section.
This section includes the trace monitoring points applicable to them as well as the interfaces over which they can send
and/or receive trace configuration.
MME
The MME support tracing of the following interfaces with the following trace capabilities:
Interface Name
Remote Device
Trace Signaling (De)Activation RX
Trace Signaling (De)Activation TX
S1a
eNodeB
N
Y
S3
SGSN
Y
Y
S6a
HSS
Y
N
S10
MME
Y
Y
S11
S-GW
N
Y
S-GW
The S-GW support tracing of the following interfaces with the following trace capabilities:
Interface Name
Remote Device
Trace Signaling (De)Activation RX
Trace Signaling (De)Activation TX
S1-U
eNodeB
Y
N
S4
SGSN
N
N
S5
P-GW (Intra-PLMN) Y
N
S8
P-GW (Inter-PLMN) N
N
S11
MME
Y
N
S12
RNC
Y
N
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Subscriber Session Trace Functional Description ▀
Interface Name
Remote Device
Trace Signaling (De)Activation RX
Trace Signaling (De)Activation TX
Gxc
Policy Server
Y
N
P-GW
The P-GW support tracing of the following interfaces with the following trace capabilities:
Interface Name
Remote Device
Trace Signaling (De)Activation RX
Trace Signaling (De)Activation TX
S2abc
Various NEs
N
N
S5
S-GW (Intra-PLMN) Y
N
S6b
AAA Server/Proxy
Y
N
S8
S-GW (Inter-PLMN) N
N
Gx
Policy Server
Y
N
SGi
IMS
Y
N
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▀ Subscriber Session Trace Configuration
Subscriber Session Trace Configuration
This section provides a high-level series of steps and the associated configuration examples for configuring the system
to enable the Subscriber Session Trace collection and monitoring function on network elements s in LTE/EPC ne tworks.
Important: This section provides the minimum instruction set to enable the Subscriber Session Trace
functionality to collect session traces on network elements on EPC networks. Commands that configure additional
function for this feature are provided in the Command Line Interface Reference.
These instructions assume that you have already configured the system level configuration as described in the System
Administration Guide and specific product Administration Guide.
To configure the system to support subscriber session trace collection and trace file transport on a system:
Step 1
Enable the subscriber session trace functionality with NE interface and TCE address at the Exec Mode level on an EPC
network element by applying the example configurations presented in the Enabling Subscriber Session Trace on EPC
Network Element section.
Step 2
Configure the network and trace file transportation parameters by applying the example configurations presented in the
Trace File Collection Configuration section.
Step 3
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Step 4
Verify the configuration of Subscriber Session Trace related parameters by applying the commands provided in the
Verifying Your Configuration section of this chapter.
Enabling Subscriber Session Trace on EPC Network Element
This section provides the configuration example to enable the subscriber session trace on a system at the Exec mode:
session trace subscriber network-element { ggsn | mme | pgw | sgw } { imei
<imei_id> } { imsi <imsi_id> } { interface { all | <interface> } } trace-ref
<trace_ref_id> collection-entity <ip_address>
Notes:
 <interface > is the name of the interfaces applicable for specific NE on which subscriber session traces have
to be collected. For more information, refer to the session trace subscriber command in the Command
Line Interface Reference.
 <trace_ref_id > is the configured Trace Id to be used for this trace collection instance. It is composed of
MCC (3 digit)+MNC (3 digit)+Trace Id (3 byte octet string).
 <ip_address > is the IP address of Trace collection Entity in IPv4 notation.
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Subscriber Session Trace Configuration ▀
Trace File Collection Configuration
This section provides the configuration example to configure the trace fil e collection parameters and protocols to be
used to store trace files on TCE through FTP/S-FTP:
configure
session trace subscriber network-element { all | ggsn | mme | pgw | sgw } [
collection-timer <dur> ] [ tce-mode { none | push transport { ftp | sftp } path
<string> username <name> { encrypted password <enc_pw> ] | password <password> }
} ]
end
Notes:
 <string > is the location/path on the trace collection entity (TCE) where trace files will be stored on TCE. For
more information, refer to the session trace command in the Command Line Interface Reference.
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▀ Verifying Your Configuration
Verifying Your Configuration
This section explains how to display and review the configurations after saving them in a .cfg file as described in the
System Administration Guide and also to retrieve errors and warnings within an active configuration for a service.
Important: All commands listed here are under Exec mode. Not all commands are available on all platforms.
These instructions are used to verify the Subscriber Session Trace configuration.
Step 1
Verify that your subscriber session support is configured properly by entering the following command in Exec Mode:
show session trace statistics
The output of this command displays the statistics of the session trace instance.
Num current trace sessions: 5
Total trace sessions activated: 15
Total Number of trace session activation failures: 2
Total Number of trace recording sessions triggered: 15
Total Number of messages traced: 123
Number of current TCE connections: 2
Total number of TCE connections: 3
Total number of files uploaded to all TCEs: 34
Step 2
View the session trace references active for various network elements in an EPC network by entering the following
command in Exec Mode:
show session trace trace-summary
The output of this command displays the summary of trace references for all network elements:
MME
Trace Reference: 310012012345
Trace Reference: 310012012346
SGW
Trace Reference: 310012012345
Trace Reference: 310012012346
PGW
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Verifying Your Configuration ▀
Trace Reference: 310012012347
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Chapter 7
Monitoring the Service
This chapter provides information for monitoring service status and performance using the show commands found in
the Command Line Interface (CLI). These command have many related keywords that allow them to provide useful
information on all aspects of the system ranging from current software configuration through call activity and status.
The selection of keywords described in this chapter is intended to provided the most useful and in -depth information for
monitoring the system. For additional information on these and other show command keywords, refer to the Command
Line Interface Reference.
In addition to the CLI, the system supports the sending of Simple Network Management Protocol (SNMP) traps that
indicate status and alarm conditions. Refer to the SNMP MIB Reference for a detailed listing of these traps.
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▀ Monitoring System Status and Performance
Monitoring System Status and Performance
This section contains commands used to monitor the status of tasks, managers, applications and other software
components in the system. Output descriptions for most of the commands are located in the Statistics and Counters
Reference.
Table 21. System Status and Performance Monitoring Commands
To do this:
Enter this command:
View Congestion-Control Information
View Congestion-Control Statistics
show congestion-control statistics {a11mgr |
ipsecmgr}
View GTP Information
View eGTP-C service statistics for a specific service
show egtpc statistics egtpc-service name
View eGTP-C service information for a specific service
show egtpc-service name
View GTP-U service statistics for all GTP-U data traffic on the
system
show gtpu statistics
View eGTP-U service information for a specific service
show gtpu-service name
View Infrastructure-DNS Queries
Verify Infrastructure-DNS queries to resolve P-CSCF FQDN
dns-client query client-name client_name
query-type AAAA query-name <p-cscf.com>
View IP Information
Display BGP Neighbors
Verify BGP neighbors on egress P-GW context
context egress_pgw_context_name
show ip bgp summary
Verify BGP neighbors on ingress P-GW context
context ingress_pgw_context_name
show ip bgp summary
Display IP Connectivity State
Verify IP connectivity to the diameter servers for various
components/interfaces; all peers should be in OPEN or
WAIT_DWR state
show diameter peers full all |grep State
Display IP Interface Status
Verify IP interfaces are up on each context
show ip interface summary
show ipv6 interface summary
Display IP Pool Configuration
Verify IPv4 pools have been created and are available
context egress_pgw_context_name
show ip pool summary
Verify IPv6 pools have been created and are available
context egress_pgw_context_name
show ipv6 pool summary
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Monitoring System Status and Performance ▀
To do this:
Enter this command:
View SAEGW Service Information
View SAEGW service statistics
show saegw-service statistics all
Verify SAEGW services
context saegw_context_name
show saegw-service all |grep Status
View S-GW Service Information
View S-GW service statistics
show sgw-service statistics all
Verify S-GW services
show sgw-service all |grep Status
show mag-service all |grep Status
View P-GW Service Information
View P-GW service statistics
show pgw-service statistics all
Verify P-GW services
show
show
show
show
pgw-service all |grep Status
lma-service all |grep Status
egtp-service all |grep Status
gtpu-service all |grep State
View LMA Service Information
View LMA service statistics for a specific service
show lma-service statistics lma-service
service_name
View QoS/QCI Information
View QoS Class Index to QoS mapping tables
show qci-qos-mapping table all
View RF Accounting Information
Confirm the PGW is sending Rf accounting records:
 Verify “Message sent” is non-zero

Verify active charging sessions are present
show diameter accounting servers |grep
Message
show active-charging sessions all |more
View Session Subsystem and Task Information
Display Session Subsystem and Task Statistics
Important: Refer to the System Software Task and Subsystem Descriptions appendix in the System
Administration Guide for additional information on the Session subsystem and its various manager tasks.
View AAA Manager statistics
show session subsystem facility aaamgr all
View AAA Proxy statistics
show session subsystem facility aaaproxy all
View LMA Manager statistics
show session subsystem facility hamgr all
View MAG Manager statistics
show session subsystem facility magmgr all
View Session Manager statistics
show session subsystem facility sessmgr all
View Session Disconnect Reasons
View session disconnect reasons with verbose output
show session disconnect-reasons
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To do this:
Enter this command:
View Session Recovery Information
View session recovery status
show session recovery status [ verbose ]
View Subscriber Information
Display NAT Information
View the private IP assigned to the NAT user, along with any
other public IPs assigned
show subscriber full username user_name
View NAT realms assigned to this user
show subscriber full username user_name |grep
-i nat
View active charging flows for a specific NAT IP address
show active-charging flows full nat required
nat-ip ip_address
Display Session Resource Status
View session resource status
show resources session
View Statistics for Subscribers using SAEGW Services on the System
View statistics for subscribers using any SAEGW service on the
system
show subscribers saegw-only full
View statistics for subscribers using a specific S-GW service on
the system
show subscribers saegw-service service_name
View Statistics for Subscribers using S-GW Services on the System
View statistics for subscribers using any S-GW service on the
system
show subscribers sgw-only full
View statistics for subscribers using a specific S-GW service on
the system
show subscribers sgw-service service_name
View Statistics for Subscribers using P-GW Services on the System
View statistics for subscribers using any P-GW service on the
system
show subscribers pgw-only full
View statistics for subscribers using a specific P-GW interface
show subscribers pgw-address ip_address
View Statistics for Subscribers using MAG Services on the System
View statistics for subscribers using any MAG service on the
system
show subscribers mag-only full
View statistics for subscribers using a specific MAG service on
the system
show subscribers mag-service service_name
View Statistics for Subscribers using LMA Services on the System
View statistics for subscribers using a specific LMA service on
the system
show subscribers lma-service service_name
Display Subscriber Configuration Information
View locally configured subscriber profile settings (must be in
context where subscriber resides)
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show subscribers configuration username
subscriber_name
Monitoring the Service
Monitoring System Status and Performance ▀
To do this:
Enter this command:
View remotely configured subscriber profile settings
show subscribers aaa-configuration username
subscriber_name
View Subscribers Currently Accessing the System
View a listing of subscribers currently accessing the system
show subscribers all
Display UE Attach Status
Confirm that a UE has attached:
 Displays IMSI with one entry for each bearer per APN
connection

Verify active charging sessions are present

Verify peers are active. Peers should correspond to SGW EGTP addresses

Verify “Create Session Request” and “Create Session
Response” categories are incrementing

Verify “Total Data Stats:” are incrementing
show
show
show
show
show
subscriber pgw-only imsi ue_imsi
active-charging sessions all |more
egtpc peers
egtpc statistics
gtpu statistics
eHRPD only
show lma-service session username user_name
show lma-service statistics
eHRPD:
 Verify lma-sessions are present

Verify “Binding Updates Received:” categories are
incrementing
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▀ Clearing Statistics and Counters
Clearing Statistics and Counters
It may be necessary to periodically clear statistics and counters in order to gather new information. The system provides
the ability to clear statistics and counters based on their grouping (PPP, MIPHA, MIPFA, etc.).
Statistics and counters can be cleared using the CLI clear command. Refer to the Command Line Reference for
detailed information on using this command.
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Appendix A
CoA, RADIUS DM, and Session Redirection (Hotlining)
This chapter describes Change of Authorization (CoA), Disconnect Message (DM), and Session Redirect (Hotlining)
support in the system. RADIUS attributes, Access Control Lists (ACLs) and filters that are used to implement these
features are discussed. The product administration guides provide examples and procedures for configuration of basic
services on the system. It is recommended that you select the configuration example that best meets your service model,
and configure the required elements for that model, as described in this Administration Guide, before using the
procedures in this chapter.
Important: Not all functions, commands, and keywords/variables are available or supported for all network
function or services. This depends on the platform type and the installed license(s).
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▀ RADIUS Change of Authorization and Disconnect Message
RADIUS Change of Authorization and Disconnect Message
This section describes how the system implements CoA and DM RADIUS messages and how to configure the system to
use and respond to CoA and DM messages.
CoA Overview
The system supports CoA messages from the AAA server to change data filters associated with a subscriber session.
The CoA request message from the AAA server must contain attributes to identify NAS and the subscriber session and a
data filter ID for the data filter to apply to the subscriber session. The filter-id attribute (attribute ID 11) contains the
name of an Access Control List (ACL). For detailed information on configuring ACLs, refer to t he IP Access Control
Lists chapter in the System Administration Guide.
If the system successfully executes a CoA request, a CoA-ACK message is sent back to the RADIUS server and the data
filter is applied to the subscriber session. Otherwise, a CoA-NAK message is sent with an error-cause attribute without
making any changes to the subscriber session.
Important: Changing ACL and rulebase together in a single CoA is not supported. For this, two separate CoA
requests can be sent through AAA server requesting for one attribute change per request.
DM Overview
The DM message is used to disconnect subscriber sessions in the system from a RADIUS server. The DM request
message should contain necessary attributes to identify the subscriber session. If the system successfully disconnects the
subscriber session, a DM-ACK message is sent back to the RADIUS server, otherwise, a DM-NAK message is sent
with proper error reasons.
License Requirements
The RADIUS Change of Authorization (CoA) and Disconnect Message (DM) are licensed Cisco features. A separate
feature license may be required. Contact your Cisco account representative for detailed information on specific licensing
requirements. For information on installing and verifying licenses, refer to the Managing License Keys section of the
Software Management Operations chapter in the System Administration Guide.
Enabling CoA and DM
To enable RADIUS Change of Authorization and Disconnect Message:
Step 1
Enable the system to listen for and respond to CoA and DM messages from the RADIUS server as described in the
Enabling CoA and DM section.
Step 2
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
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Step 3
View CoA and DM message statistics as described in the Viewing CoA and DM Statistics section.
Important: Commands used in the configuration examples in this section provide base functionality to
the extent that the most common or likely commands and/or keyword options are presented. In many cases,
other optional commands and/or keyword options are available. Refer to the Command Line Interface
Reference for complete information regarding all commands. Not all commands and keywords/variables are
available or supported. This depends on the platform type and the installed license(s).
Enabling CoA and DM
Use the following example to enable the system to listen for and respond to CoA and DM messages from the RADIUS
server:
configure
context <context_name>
radius change-authorize-nas-ip <ipv4/ipv6_address>
end
Notes:
 <context_name> must be the name of the AAA context where you want to enable CoA and DM.
For more information on configuring the AAA context, if you are using StarOS 12.3 or an earlier release, refer
to the Configuring Context-Level AAA Functionality section of the AAA and GTPP Interface Administration
and Reference. If you are using StarOS 14.0 or a later release, refer to the AAA Interface Administration and
Reference.
 A number of optional keywords and variables are available for the radius change-authorize-nas-ip
command. For more information regarding this command please refer to the Command Line Interface
Reference.
CoA and DM Attributes
For CoA and DM messages to be accepted and acted upon, the system and subscriber session to be affected must be
identified correctly.
To identify the system, use any one of the following attributes:
 NAS-IP-Address: NAS IP address if present in the CoA/DM request should match with the NAS IP address.
 NAS-Identifier: If this attribute is present, its value should match to the nas-identifier generated for the
subscriber session
To identify the subscriber session, use any one of the following attributes.
 If 3GPP2 service is configured the following attribute is used for correlation identifier:
 3GPP2-Correlation-ID: The values should exactly match the 3GPP2-correlation-id of the subscriber
session. This is one of the preferred methods of subscriber session identification.
 If 3GPP service is configured the following attributes are used for different identifiers:
 3GPP-IMSI: International Mobile Subscriber Identification (IMSI) number should be validated and
matched with the specified IMSI for specific PDP context.
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 3GPP-NSAPI: Network Service Access Point Identifier (NSAPI) should match to the NSAPI specified
for specific PDP context.
 User-Name: The value should exactly match the subscriber name of the session. This is one of the preferred
methods of subscriber session identification.
 Framed-IP-Address: The values should exactly match the framed IP address of the session.
 Calling-station-id: The value should match the Mobile Station ID.
To specify the ACL to apply to the subscriber session, use the following attribute:
 Filter-ID: CoA only. This must be the name of an existing Access Control List. If this is present in a CoA
request, the specified ACL is immediately applied to the specified subscriber session. The Context
Configuration mode command, radius attribute filter-id direction, controls in which direction filters are
applied.
The following attributes are also supported:
 Event-Timestamp: This attribute is a timestamp of when the event being logged occurred.
 If 3GPP2 service is configured following additional attributes are supported:
 3GPP2-Disconnect-Reason: This attribute indicates the reason for disconnecting the user. This attribute
may be present in the RADIUS Disconnect-request Message from the Home Radius server to the
PDSN.
 3GPP2-Session-Termination-Capability: When CoA and DM are enabled by issuing the radius changeauthorize-nas-ip command, this attribute is included in a RADIUS Access-request message to the
Home RADIUS server and contains the value 3 to indicate that the system supports both Dynamic
authorization with RADIUS and Registration Revocation for Mobile IPv4. The attribute is also
included in the RADIUS Access-Accept message and contains the preferred resource management
mechanism by the home network, which is used for the session and may include values 1 through 3.
CoA and DM Error-Cause Attribute
The Error-Cause attribute is used to convey the results of requests to the system. This attribute is present when a CoA or
DM NAK or ACK message is sent back to the RADIUS server.
The value classes of error causes are as follows:
 0-199, 300-399 reserved
 200-299 - successful completion
 400-499 - errors in RADIUS server
 500-599 - errors in NAS/Proxy
The following error cause is sent in ACK messages upon successful completion of a CoA or DM request:
 201- Residual Session Context Removed
The following error causes are sent in NAK messages when a CoA or DM request fails:
 401 - Unsupported Attribute
 402 - Missing Attribute
 403 - NAS Identification Mismatch
 404 - Invalid Request
 405 - Unsupported Service
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 406 - Unsupported Extension
 501 - Administratively Prohibited
 503 - Session Context Not Found
 504 - Session Context Not Removable
 506 - Resources Unavailable
Viewing CoA and DM Statistics
View CoA and DM message statistics by entering the following command:
show session subsystem facility aaamgr
The following is a sample output of this command.
1 AAA Managers
807 Total aaa requests
0 Current aaa requests
379 Total aaa auth requests
0 Current aaa auth requests
0 Total aaa auth probes
0 Current aaa auth probes
0 Total aaa auth keepalive
0 Current aaa auth keepalive
426 Total aaa acct requests
0 Total aaa acct keepalive
379 Total aaa auth success
0 Current aaa acct requests
0 Current aaa acct keepalive
0 Total aaa auth failure
0 Total aaa auth purged
0 Total aaa auth cancelled
0 Total auth keepalive success
0 Total auth keepalive failure
0 Total auth keepalive purged
0 Total aaa auth DMU challenged
367 Total radius auth requests
0 Current radius auth requests
2 Total radius auth requests retried
0 Total radius auth responses dropped
0 Total local auth requests
12 Total pseudo auth requests
0 Current local auth requests
0 Current pseudo auth requests
0 Total null-username auth requests (rejected)
0 Total aaa acct completed
0 Total aaa acct purged
0 Total acct keepalive success
0 Total acct keepalive timeout
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0 Total acct keepalive purged
0 Total aaa acct cancelled
426 Total radius acct requests
0 Current radius acct requests
0 Total radius acct requests retried
0 Total radius acct responses dropped
0 Total gtpp acct requests
0 Current gtpp acct requests
0 Total gtpp acct cancelled
0 Total gtpp acct purged
0 Total null acct requests
0 Current null acct requests
54 Total aaa acct sessions
5 Current aaa acct sessions
3 Total aaa acct archived
0 Current aaa acct archived
0 Current recovery archives
0 Current valid recovery records
2 Total aaa sockets opened
2 Current aaa sockets open
0 Total aaa requests pend socket open
0 Current aaa requests pend socket open
0 Total radius requests pend server max -outstanding
0 Current radius requests pend server max -outstanding
0 Total aaa radius coa requests
0 Total aaa radius dm requests
0 Total aaa radius coa acks
0 Total aaa radius dm acks
0 Total aaa radius coa naks
0 Total aaa radius dm naks
2 Total radius charg auth
0 Current radius charg auth
0 Total radius charg auth succ
0 Total radius charg auth fail
0 Total radius charg auth purg
0 Total radius charg auth cancel
0 Total radius charg acct
0 Current radius charg acct
0 Total radius charg acct succ
0 Total radius charg acct purg
0 Total radius charg acct cancel
357 Total gtpp charg
0 Current gtpp charg
357 Total gtpp charg success
0 Total gtpp charg failure
0 Total gtpp charg cancel
0 Total gtpp charg purg
0 Total prepaid online requests
0 Current prepaid online requests
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0 Total prepaid online success
0 Current prepaid online failure
0 Total prepaid online retried
0 Total prepaid online cancelled
0 Current prepaid online purged
0 Total aaamgr purged requests
0 SGSN: Total db records
0 SGSN: Total sub db records
0 SGSN: Total mm records
0 SGSN: Total pdp records
0 SGSN: Total auth records
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Session Redirection (Hotlining)
Important: Functionality described for this feature in this segment is not applicable for HNB-GW sessions.
Overview
Session redirection provides a means to redirect subscriber traffic to an external server by applying ACL rules to the
traffic of an existing or a new subscriber session. The destination address and optionally the destination port of TCP/IP
or UDP/IP packets from the subscriber are rewritten so the packet is forwarded to the designated redirected address.
Return traffic to the subscriber has the source address and port rewritten to the original values. The redirect ACL may be
applied dynamically by means of the RADIUS Change of Authorization (CoA) feature.
Note that the session redirection feature is only intended to redirect a very small subset of subscribers at any given time.
The data structures allocated for this feature are kept to the minimum to avoid large memory overhead in the session
managers.
License Requirements
The Session Redirection (Hotlining) is a licensed Cisco feature. A separate feature license may be required. Contact
your Cisco account representative for detailed information on specific licensing requirements. For information on
installing and verifying licenses, refer to the Managing License Keys section of the Software Management Operations
chapter in the System Administration Guide.
Operation
ACL Rule
An ACL rule named readdress server supports redirection of subscriber sessions. The ACL containing this rule must
be configured in the destination context of the user. Only TCP and UDP protocol packets are supported. The ACL rule
allows specifying the redirected address and an optional port. The source and destination address and ports (with respect
to the traffic originating from the subscriber) may be wildcarded. If the redirected port is not specified, the traffic will be
redirected to the same port as the original destination port in the datagrams. For detailed information on configuring
ACLs, refer to the IP Access Control Lists chapter in the System Administration Guide. For more information on
readdress server, refer to the ACL Configuration Mode Commands chapter of the Command Line Interface Reference.
Redirecting Subscriber Sessions
An ACL with the readdress server rule is applied to an existing subscriber session through CoA messages from the
RADIUS server. The CoA message contains the 3GPP2-Correlation-ID, User-Name, Acct-Session-ID, or Framed-IPAddress attributes to identify the subscriber session. The CoA message also contains the Filter-Id attribute which
specifies the name of the ACL with the readdress server rule. This enables applying the ACL dynamically to existing
subscriber sessions. By default, the ACL is applied as both the input and output filter for the matching subscriber unless
the Filter-Id in the CoA message bears the prefix in: or out:.
For information on CoA messages and how they are implemented in the system, refer to the RADIUS Change of
Authorization and Disconnect Message section.
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Important: Changing ACL and rulebase together in a single CoA is not supported. For this, two separate CoA
requests can be sent through AAA server requesting for one attribute change per request.
Session Limits On Redirection
To limit the amount of memory consumed by a session manager a limit of 2000 redirected sessio n entries per session
manager is allocated. This limit is equally shared by the set of subscribers who are currently being redirected. Whenever
a redirected session entry is subject to revocation from a subscriber due to an insufficient number of available session
entries, the least recently used entry is revoked.
Stopping Redirection
The redirected session entries for a subscriber remain active until a CoA message issued from the RADIUS server
specifies a filter that does not contain the readdress server ACL rule. When this happens, the redirected session entries
for the subscriber are deleted.
All redirected session entries are also deleted when the subscriber disconnects.
Handling IP Fragments
Since TCP/UDP port numbers are part of the redirection mechanism, fragmented IP datagrams must be reassembled
before being redirected. Reassembly is particularly necessary when fragments are sent out of order. The session
manager performs reassembly of datagrams and reassembly is attempted only when a datagram matches the redirect
server ACL rule. To limit memory usage, only up to 10 different datagrams may be concurrently reassembled for a
subscriber. Any additional requests cause the oldest datagram being reassembled to be discarded. The reassembly
timeout is set to 2 seconds. In addition, the limit on the total number of fragments being reassembled by a session
manager is set to 1000. If this limit is reached, the oldest datagram being reassembled in the session manager and its
fragment list are discarded. These limits are not configurable.
Recovery
When a session manager dies, the ACL rules are recovered. The session redirect entries have to be re-created when the
MN initiates new traffic for the session. Therefore when a crash occurs, traffic from the Internet side is not redirected to
the MN.
AAA Accounting
Where destination-based accounting is implemented, traffic from the subscriber is accounted for using the original
destination address and not the redirected address.
Viewing the Redirected Session Entries for a Subscriber
View the redirected session entries for a subscriber by entering the following command:
show subscribers debug-info { callid <id> | msid <id> | username <name> }
The following command displays debug information for a subscriber with the MSID 0000012345:
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show subscribers debug-info msid 0000012345
The following is a sample output of this command:
username: user1 callid: 01ca11b1 msid: 0000100003
Card/Cpu: 4/2
Sessmgr Instance: 7
Primary callline:
Redundancy Status: Original Session
Checkpoints Attempts Success Last-Attempt Last-Success
Full: 27 26 15700ms 15700ms
Micro: 76 76 4200ms 4200ms
Current state: SMGR_STATE_CONNECTED
FSM Event trace:
State Event
SMGR_STATE_OPEN SMGR_EVT_NEWCALL SMGR_STATE_NEWCALL_ARRIVED SMGR_EVT_ANSWER_CALL
SMGR_STATE_NEWCALL_ANSWERED SMGR_EVT_LINE_CONNECTED SMGR_STATE_LINE_CONNECTED
SMGR_EVT_LINK_CONTROL_UP SMGR_STATE_LINE_CONNECTED SMGR_EVT_AUTH_REQ
SMGR_STATE_LINE_CONNECTED SMGR_EVT_IPADDR_ALLOC_SUCCESS
SMGR_STATE_LINE_CONNECTED SMGR_EVT_AUTH_SUCCESS
SMGR_STATE_LINE_CONNECTED SMGR_EVT_UPDATE_SESS_CONFIG
SMGR_STATE_LINE_CONNECTED SMGR_EVT_LOWER_LAYER_UP
Data Reorder statistics
Total timer expiry: 0 Total flush (tmr expiry): 0
Total no buffers: 0 Total flush (no buffers): 0
Total flush (queue full): 0 Total flush (out of range):0
Total flush (svc change): 0 Total out-of-seq pkt drop: 0
Total out-of-seq arrived: 0
IPv4 Reassembly Statistics:
Success: 0 In Progress: 0
Failure (timeout): 0 Failure (no buffers): 0
Failure (other reasons): 0
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Redirected Session Entries:
Allowed: 2000 Current: 0
Added: 0 Deleted: 0
Revoked for use by different subscriber: 0
Peer callline:
Redundancy Status: Original Session
Checkpoints Attempts Success Last-Attempt Last-Success
Full: 0 0 0ms 0ms
Micro: 0 0 0ms 0ms
Current state: SMGR_STATE_CONNECTED
FSM Event trace:
State Event
SMGR_STATE_OPEN SMGR_EVT_MAKECALL
SMGR_STATE_MAKECALL_PENDING SMGR_EVT_LINE_CONNECTED
SMGR_STATE_LINE_CONNECTED SMGR_EVT_LOWER_LAYER_UP
SMGR_STATE_CONNECTED SMGR_EVT_AUTH_REQ
SMGR_STATE_CONNECTED SMGR_EVT_AUTH_SUCCESS
SMGR_STATE_CONNECTED SMGR_EVT_REQ_SUB_SESSION
SMGR_STATE_CONNECTED SMGR_EVT_RSP_SUB_SESSION
username: user1 callid: 01ca11b1 msid: 0000100003
Card/Cpu: 4/2
Sessmgr Instance: 7
Primary callline:
Redundancy Status: Original Session
Checkpoints Attempts Success Last-Attempt Last-Success
Full: 27 26 15700ms 15700ms
Micro: 76 76 4200ms 4200ms
Current state: SMGR_STATE_CONNECTED
FSM Event trace:
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State Event
SMGR_STATE_OPEN SMGR_EVT_NEWCALL
SMGR_STATE_NEWCALL_ARRIVED SMGR_EVT_ANSWER_CALL
SMGR_STATE_NEWCALL_ANSWERED SMGR_EVT_LINE_CONNECTED
SMGR_STATE_LINE_CONNECTED SMGR_EVT_LINK_CONTROL_UP
SMGR_STATE_LINE_CONNECTED SMGR_EVT_AUTH_REQ
SMGR_STATE_LINE_CONNECTED SMGR_EVT_IPADDR_ALLO C_SUCCESS
SMGR_STATE_LINE_CONNECTED SMGR_EVT_AUTH_SUCCESS
SMGR_STATE_LINE_CONNECTED SMGR_EVT_UPDATE_SESS_CONFIG
SMGR_STATE_LINE_CONNECTED SMGR_EVT_LOWER_LAYER_UP
Data Reorder statistics
Total timer expiry: 0 Total flush (tmr expiry): 0
Total no buffers: 0 Total flush (no buffers): 0
Total flush (queue full): 0 Total flush (out of range):0
Total flush (svc change): 0 Total out-of-seq pkt drop: 0
Total out-of-seq arrived: 0
IPv4 Reassembly Statistics:
Success: 0 In Progress: 0
Failure (timeout): 0 Failure (no buffers): 0
Failure (other reasons): 0
Redirected Session Entries:
Allowed: 2000 Current: 0
Added: 0 Deleted: 0
Revoked for use by different subscriber: 0
Peer callline:
Redundancy Status: Original Session
Checkpoints Attempts Success Last-Attempt Last-Success
Full: 0 0 0ms 0ms
Micro: 0 0 0ms 0ms
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Current state: SMGR_STATE_CONNECTED
FSM Event trace:
State Event
SMGR_STATE_OPEN SMGR_EVT_MAKECALL
SMGR_STATE_MAKECALL_PENDING SMGR_EVT_LINE_CONNECTED
SMGR_STATE_LINE_CONNECTED SMGR_EVT_LOWER_LAYER_UP
SMGR_STATE_CONNECTED SMGR_EVT_AUTH_REQ
SMGR_STATE_CONNECTED SMGR_EVT_AUTH_SUCCESS
SMGR_STATE_CONNECTED SMGR_EVT_REQ_SUB_SESSION
SMGR_STATE_CONNECTED SMGR_EVT_RSP_SUB_SESSION
SMGR_STATE_CONNECTED SMGR_EVT_ADD_SUB_SESSION
SMGR_STATE_CONNECTED SMGR_EVT_AUTH_REQ
SMGR_STATE_CONNECTED SMGR_EVT_AUTH_SUCCESS
Data Reorder statistics
Total timer expiry: 0 Total flush (tmr expiry): 0
Total no buffers: 0 Total flush (no buffers): 0
Total flush (queue full): 0 Total flush (out of range):0
Total flush (svc change): 0 Total out-of-seq pkt drop: 0
Total out-of-seq arrived: 0
IPv4 Reassembly Statistics:
Success: 0 In Progress: 0
Failure (timeout): 0 Failure (no buffers): 0
Failure (other reasons): 0
Redirected Session Entries:
Allowed: 2000 Current: 0
Added: 0 Deleted: 0
Revoked for use by different subscriber: 0
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Appendix B
Direct Tunnel
This chapter briefly describes the 3G/4G UMTS direct tunnel (DT) feature, indicates how it is implemented on various
systems on a per call basis, and provides feature configuration procedures.
Products supporting direct tunnel include:
 3G devices (per 3GPP TS 23.919 v8.0.0):
 the Serving GPRS Support Node (SGSN)
 the Gateway GPRS Support Node (GGSN)
 LTE devices (per 3GPP TS 23.401 v8.3.0):
 Serving Gateway (S-GW)
 PDN Gateway (P-GW)
Important: Direct tunnel is a licensed Cisco feature. A separate feature license is required for configuration.
Contact your Cisco account representative for detailed information on specific licensing requirements. For information
on installing and verifying licenses, refer to the Managing License Keys section of the Software Management
Operations chapter in the System Administration Guide.
The SGSN determines if setup of a direct tunnel is allowed or disallowed. Currently, the SGSN and S-GW are the only
products that provide configuration commands for this feature. All other products that support direct tunnel do so by
default.
This chapter provides the following information:
 Direct Tunnel Feature Overview
 Direct Tunnel Configuration
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Direct Tunnel Feature Overview
The direct tunnel architecture allows the establishment of a direct user plane (GTP-U) tunnel between the radio access
network equipment (RNC) and the GGSN/P-GW.
Once a direct tunnel is established, the SGSN/S-GW continues to handle the control plane (RANAP/GTP-C) signaling
and retains the responsibility of making the decision to establish direct tunnel at PDN context activation.
Figure 32.
GTP-U Direct Tunneling
A direct tunnel improves the user experience (for example, expedites web page delivery, reduces round trip delay for
conversational services) by eliminating switching latency from the user plane. An additional advantage, direct tunnel
functionality implements optimization to improve the usage of user plane resources (and hardware) by removing the
requirement from the SGSN/S-GW to handle the user plane processing.
A direct tunnel is achieved upon PDN context activation in the following ways:
 3G network: The SGSN establishes a user plane (GTP-U) tunnel directly between the RNC and the GGSN,
using an Updated PDN Context Request toward the GGSN.
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1. Direct Tunneling - 3G Network
 LTE network: When Gn/Gp interworking with pre-release 8 (3GPP) SGSNs is enabled, the GGSN service on
the P-GW supports direct tunnel functionality. The SGSN establishes a user plane (GTP-U) tunnel directly
between the RNC and the GGSN/P-GW, using an Update PDN Context Request toward the GGSN/P-GW.
2. Direct Tunneling - LTE Network, GTP-U Tunnel
 LTE network: The SGSN establishes a user plane tunnel (GTP-U tunnel over an S12 interface) directly between
the RNC and the S-GW, using an Update PDN Context Request toward the S-GW.
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3. Direct Tunneling - LTE Network, S12 Interface
A major consequence of deploying a direct tunnel is that it produces a significant increase in control plane load on both
the SGSN/S-GW and GGSN/P-GW components of the packet core. Hence, deployment requires highly scalable
GGSNs/P-GWs since the volume and frequency of Update PDP Context messages to the GGSN/P-GW will increase
substantially. The SGSN/S-GW platform capabilities ensure control plane capacity will not be a limiting factor with
direct tunnel deployment.
The following figure illustrates the logic used within the SGSN/S-GW to determine if a direct tunnel will be setup.
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Figure 33.
Direct Tunneling - Establishment Logic
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Direct Tunnel Configuration
The following configurations are provided in this section:
 Configuring Direct Tunnel Support on the SGSN
 Configuring S12 Direct Tunnel Support on the S-GW
The SGSN/S-GW direct tunnel functionality is enabled within an operator policy configuration. One aspect of an
operator policy is to allow or disallow the setup of direct GTP-U tunnels. If no operator policies are configured, the
system looks at the settings in the system operator policy named default.
By default, direct tunnel support is
 disallowed on the SGSN/S-GW
 allowed on the GGSN/P-GW.
Important: If direct tunnel is allowed in the default operator policy, then any incoming call that does not have
an applicable operator policy configured will have direct tunnel allowed.
For more information about operator policies and configuration details, refer to Operator Policy.
Configuring Direct Tunnel Support on the SGSN
The following is a high-level view of the steps, and the associated configuration examples, to configure the SGSN to
setup a direct tunnel.
Before beginning any of the following procedures, you must have completed (1) the basic service configuration for the
SGSN, as described in the Cisco ASR Serving GPRS Support Node Administration Guide, and (2) the creation and
configuration of a valid operator policy, as described in the Operator Policy chapter in this guide.
Step 1
Configure the SGSN to setup GTP-U direct tunnel between an RNC and an access gateway by applying the example
configuration presented in the Enabling Setup of GTP-U Direct Tunnels section below.
Step 2
Configure the SGSN to allow GTP-U direct tunnels to an access gateway, for a call filtered on the basis of the APN, by
applying the example configuration presented in the Enabling Direct Tunnel per APN section below.
Important: It is only necessary to complete either step 2 or step 3 as a direct tunnel can not be setup
on the basis of call filtering matched with both an APN profile and an IIMEI profile.
Step 3
Configure the SGSN to allow GTP-U direct tunnels to a GGSN, for a call filtered on the basis of the IMEI, by applying
the example configuration presented in the Enabling Direct Tunnel per IMEI section below.
Step 4
Configure the SGSN to allow GTP-U direct tunnel setup from a specific RNC by applying the example configuration
presented in the Enabling Direct Tunnel to Specific RNCs section below.
Step 5
(Optional) Configure the SGSN to disallow direct tunnel setup to a single GGSN that has been configured to allow it in
the APN profile. This command allows the operator to restrict use of a GGSN for any reason, such as load balancing.
Refer to the direct-tunnel-disabled-ggsn command in the SGTP Service Configuration Mode chapter of the
Command Line Interface Reference.
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Step 6
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Step 7
Check that your configuration changes have been saved by using the sample configuration found in the Verifying the
SGSN Direct Tunnel Configuration section in this chapter.
Enabling Setup of GTP-U Direct Tunnels
The SGSN determines whether a direct tunnel can be setup and by default the SGSN doesn’t support direct tunnel.
Example Configuration
Enabling direct tunnel setup on an SGSN is done by configuring direct tunnel support in a call-control profile.
config
call-control-profile <policy_name>
direct-tunnel attempt-when-permitted
end
Notes:
 A call-control profile must have been previously created, configured, and associated with a previously created,
configured, and valid operator policy. For information about operator policy creation/configuration, refer to the
Operator Policy chapter in this guide.
 Direct tunnel is now allowed on the SGSN but will only setup if allowed on both the destination node and the
RNC.
Enabling Direct Tunnel per APN
In each operator policy, APN profiles are configured to connect to one or more GGSNs and to control the direct tunnel
access to that GGSN based on call filtering by APN. Multiple APN profiles can be configured per operator policy.
By default, APN-based direct tunnel functionality is allowed so any existing direct tunnel configuration must be
removed to return to default and to ensure that the setup has not been restricted.
Example Configuration
The following is an example of the commands used to ensure that direct tunneling, to a GGSN(s) identified in the APN
profile, is enabled:
config
apn-profile <profile_name>
remove direct tunnel
end
Notes:
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▀ Direct Tunnel Configuration
 An APN profile must have been previously created, configured, and associated with a previously created,
configured, and valid operator policy. For information about operator policy creation/configuration, refer to the
Operator Policy chapter in this guide.
 Direct tunnel is now allowed for the APN but will only setup if also allowed on the RNC.
Enabling Direct Tunnel per IMEI
Some operator policy filtering of calls is done on the basis of international mobile equipment identity (IMEI) so the
direct tunnel setup may rely upon the feature configuration in the IMEI profile.
The IMEI profile basis its permissions for direct tunnel on the RNC configuration associated with the IuPS service.
By default, direct tunnel functionality is enabled for all RNCs.
Example Configuration
The following is an example of the commands used to enable direct tunneling in the IMEI profile:
config
imei-profile <profile_name>
direct-tunnel check-iups-service
end
Notes:
 An IMEI profile must have been previously created, configured, and associated with a previously created,
configured, and valid operator policy. For information about operator policy creation/configuration, refer to the
Operator Policy chapter in this guide.
 Direct tunnel is now allowed for calls within the IMEI range associated with the IMEI profile but a direct tunnel
will only setup if also allowed on the RNC.
Enabling Direct Tunnel to Specific RNCs
SGSN access to radio access controllers (RNCs) is configured in the IuPS service.
Each IuPS service can include multiple RNC configurations that determine communications and features depending on
the RNC.
By default, direct tunnel functionality is enabled for all RNCs.
Example Configuration
The following is an example of the commands used to ensure that restrictive configuration is removed and direct tunnel
for the RNC is enabled:
config
context <ctx_name>
iups-service <service_name>
rnc id <rnc_id>
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default direct-tunnel
end
Notes:
 An IuPS service must have been previously created, and configured.
 An RNC configuration must have been previously created within an IuPS service configuration.
 Command details for configuration can be found in the Command Line Interface Reference.
Verifying the SGSN Direct Tunnel Configuration
Enabling the setup of a GTP-U direct tunnel on the SGSN is not a straight forward task. It is controlled by an operator
policy with related configuration in multiple components. Each of these component configurations must be checked to
ensure that the direct tunnel configuration has been completed. You need to begin with the operator policy itself.
Verifying the Operator Policy Configuration
For the feature to be enabled, it must be allowed in the call-control profile and the call-control profile must be associated
with an operator policy. As well, either an APN profile or an IMEI profile must have been created/configured and
associated with the same operator policy. Use the following command to display and verify the operator policy and the
association of the required profiles:
show operator-policy full name <policy_name>
The output of this command displays profiles associated with the operator policy.
[local]asr5x00# show operator-policy full name oppolicy1
Operator Policy Name = oppolicy1
Call Control Profile Name
Validity
: ccprofile1
: Valid
IMEI Range 99999999999990 to 99999999999995
IMEI Profile Name
Validity
: imeiprofile1
: Invalid
APN NI homers1
APN Profile Name
Validity
: apnprofile1
: Valid
APN NI visitors2
APN Profile Name
Validity
: apnprofile2
: Invalid
Notes:
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 Validity refers to the status of the profile. Valid indicates that profile has been created and associated with the
policy. Invalid means only the name of the profile has been associated with the policy.
 The operator policy itself will only be valid if one or more IMSI ranges have been associated with it - refer to the
Operator Policy chapter, in this guide, for details.
Verifying the Call-Control Profile Configuration
Use the following command to display and verify the direct tunnel configuration for the call-control profiles:
show call-control-profile full name <profile_name>
The output of this command displays all of the configuration, including direct tunnel for the specified call -control
profile.
Call Control Profile Name = ccprofile1
...
Re-Authentication
: Disabled
Direct Tunnel
: Not Restricted
GTPU Fast Path
: Disabled
..
Verifying the APN Profile Configuration
Use the following command to display and verify the direct tunnel configuration in the APN profile:
show apn-profile full name <profile_name>
The output of this command displays all of the configuration, including direct tunnel for the specified APN profile.
Call Control Profile Name = apnprofile1
...
IP Source Validation
: Disabled
Direct Tunnel
: Not Restricted
Service Restriction for Access Type > UMTS
: Disabled
..
Verifying the IMEI Profile Configuration
Use the following command to display and verify the direct tunnel configuration in the IMEI profile:
show imei-profile full name <profile_name>
The output of this command displays all of the configuration, including direct tunnel for the specified IMEI profile.
IMEI Profile Name = imeiprofile1
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Black List
: Disabled
GGSN Selection
: Disabled
Direct Tunnel
: Enabled
Verifying the RNC Configuration
Use the following command to display and verify the direct tunnel configuration in the RNC configuration:
show iups-service name
<service_name>
The output of this command displays all of the configuration, including direct tunnel for the specified IuPS service.
IService name
: iups1
...
Available RNC:
Rnc-Id
: 1
Direct Tunnel
: Not Restricted
Configuring S12 Direct Tunnel Support on the S-GW
The example in this section configures an S12 interface supporting direct tunnel bypass of the S4 SGSN for inter-RAT
handovers.
The direct tunnel capability on the S-GW is enabled by configuring an S12 interface. The S4 SGSN is then responsible
for creating the direct tunnel by sending an FTEID in a control message to the MM E over the S3 interface. The MME
forwards the FTEID to the S-GW over the S11 interfaces. The S-GW responds with it’s own U-FTEID providing the
SGSN with the identification information required to set up the direct tunnel over the S12 interface.
Use the following example to configure this feature:
configure
context <egress_context_name> -noconfirm
interface <s12_interface_name>
ip address <s12_ipv4_address_primary>
ip address <s12_ipv4_address_secondary>
exit
exit
port ethernet <slot_number/port_number>
no shutdown
bind interface <s12_interface_name> <egress_context_name>
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exit
context <egress_context_name> -noconfirm
gtpu-service <s12_gtpu_egress_service_name>
bind ipv4-address <s12_interface_ip_address>
exit
egtp-service <s12_egtp_egress_service_name>
interface-type interface-sgw-egress
validation-mode default
associate gtpu-service <s12_gtpu_egress_service_name>
gtpc bind address <s12_interface_ip_address>
exit
sgw-service <sgw_service_name> -noconfirm
associate egress-proto gtp egress-context <egress_context_name> egtp-service
<s12_egtp_egress_service_name>
end
Notes:
 The S12 interface IP address(es) can also be specified as IPv6 addresses using the ipv6 address command.
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Appendix C
GRE Protocol Interface
This chapter provides information on Generic Routing Encapsulation protocol interface support in the GGSN or P-GW
service node. The product Administration Guides provide examples and procedures for configuration of basic services
on the system. It is recommended that you select the configuration example that best meets your servi ce model, and
configure the required elements for that model, as described in the respective product Administration Guide, before
using the procedures in this chapter.
Important: GRE protocol interface support is a licensed Cisco feature. A separate feature license may be
required. Contact your Cisco account representative for detailed information on specific licensing requirements. For
information on installing and verifying licenses, refer to the Managing License Keys section of the Software
Management Operations chapter in the System Administration Guide.
Important: Commands used in the configuration samples in this section provide base functionality to the extent
that the most common or likely commands and/or keyword options are presented. In many cases, other optional
commands and/or keyword options are available. Refer to the Command Line Interface Reference for complete
information regarding all commands.
This chapter discusses following topics for GRE protocol interface support:
 Introduction
 Supported Standards
 Supported Networks and Platforms
 Services and Application on GRE Interface
 How GRE Interface Support Works
 GRE Interface Configuration
 Verifying Your Configuration
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▀ Introduction
Introduction
GRE protocol functionality adds one additional protocol on Cisco’s multimedia core platforms (ASR 5000 or higher) to
support mobile users to connect to their enterprise networks through Generic Routing Encapsulation (GRE).
GRE tunnels can be used by the enterprise customers of a carrier 1) To transport AAA packets corresponding to an APN
over a GRE tunnel to the corporate AAA servers and, 2) To transport the enterprise subscriber packets over the GRE
tunnel to the corporation gateway.
The corporate servers may have private IP addresses and hence the addresses belonging to different enterprises may be
overlapping. Each enterprise needs to be in a unique virtual routing domain, known as VRF. To differentiate the tunnels
between same set of local and remote ends, GRE Key will be used as a differentiator.
It is a common technique to enable multi-protocol local networks over a single-protocol backbone, to connect noncontiguous networks and allow virtual private networks across WANs. This mechanism encapsulates data packets from
one protocol inside a different protocol and transports the data packets unchanged across a foreign network. It is
important to note that GRE tunneling does not provide security to the encapsulated protocol, as there is no encryption
involved (like IPSEC offers, for example).
GRE Tunneling consists of three main components:
 Passenger protocol-protocol being encapsulated. For example: CLNS, IPv4 and IPv6.
 Carrier protocol-protocol that does the encapsulating. For example: GRE, IP-in-IP, L2TP, MPLS and IPSec.
 Transport protocol-protocol used to carry the encapsulated protocol. The main transport protocol is IP.
The most simplified form of the deployment scenario is shown in the following figure, in which GGSN has two APNs
talking to two corporate networks over GRE tunnels.
Figure 34.
GRE Interface Deployment Scenario
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Supported Standards ▀
Supported Standards
Support for the following standards and requests for comments (RFCs) have been added with this interface support:
 RFC 1701, Generic Routing Encapsulation (GRE)
 RFC 1702, Generic Routing Encapsulation over IPv4 networks
 RFC 2784, Generic Routing Encapsulation (GRE)
 RFC 2890, Key and Sequence Number Extensions to GRE
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▀ Supported Networks and Platforms
Supported Networks and Platforms
This feature supports all systems with StarOS Release 9.0 or later running GGSN and/or SGSN service for the core
network services. The P-GW service supports this feature with StarOS Release 12.0 or later.
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Licenses ▀
Licenses
GRE protocol interface support is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.
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▀ Services and Application on GRE Interface
Services and Application on GRE Interface
GRE interface implementation provides the following functionality with GRE protocol support.
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How GRE Interface Support Works ▀
How GRE Interface Support Works
The GRE interface provides two types of data processing; one for ingress packets and another for egress packets.
Ingress Packet Processing on GRE Interface
Figure given below provides a flow of process for incoming packets on GRE interface.
Note that in case the received packet is a GRE keep-alive or a ping packet then the outer IPV4 and GRE header are not
stripped off (or get reattached), but instead the packet is forwarded as is to the VPN manager or kernel respectively. In
case of all other GRE tunneled packets the IPV4 and GRE header are stripped off before sending the packet for a new
flow lookup.
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Figure 35.
Ingress Packet Processing on GRE Interface
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How GRE Interface Support Works ▀
Egress Packet Processing on GRE Interface
Figure given below provides a flow of process for outgoing packets on GRE interface:
Figure 36.
Egress Packet Processing on GRE Interface
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GRE Interface Configuration
This section provides a high-level series of steps and the associated configuration examples for configuring the system
with GRE interface in GGSN or P-GW services.
Important: This section provides the minimum instruction set to enable the GRE Protocol Interface support
functionality on a GGSN or P-GW. Commands that configure additional functions for this feature are provided in the
Command Line Interface Reference.
These instructions assume that you have already configured the system level configuration as described in System
Administration Guide and specific product Administration Guide.
To configure the system to support GRE tunnel interface:
Step 1
Configure the virtual routing and forwarding (VRF) in a context by applying the example configura tions presented in
the Virtual Routing And Forwarding (VRF) Configuration section.
Step 2
Configure the GRE tunnel interface in a context by applying the example configurations presented in the GRE Tunnel
Interface Configuration section.
Step 3
Enable OSPF for the VRF and for the given network by applying the example configurations presented in the Enabling
OSPF for VRF section.
Step 4
Associate IP pool and AAA server group with VRF by applying the example configurations presented in the
Associating IP Pool and AAA Group with VRF section.
Step 5
Associate APN with VRF through AAA server group and IP pool by applying the example configurations presented in
the Associating APN with VRF section.
Step 6
Optional. If the route to the server is not learnt from the corporate over OSPFv2, static route can be configured by
applying the example configurations presented in the Static Route Configuration section.
Step 7
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Step 8
Verify configuration of GRE and VRF related parameters by applying the commands provided in the Verifying Your
Configuration section of this chapter.
Virtual Routing And Forwarding (VRF) Configuration
This section provides the configuration example to configure the VRF in a context:
configure
context <vpn_context_name> -noconfirm ]
ip vrf <vrf_name>
ip maximum-routes <max_routes>
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end
Notes:
 <vpn_context_name > is the name of the system context you want to use for VRF. For more information, refer
System Administration Guide.
 A maximum of 100 VRFs in one context and up to 1024 VRFs on one chassis can be configured on system.
 <vrf_name > is name of the VRF which is to be associated with various interfaces.
 A maximum of 10000 routes can be configured through ip maximum-routes <max_routes > command.
GRE Tunnel Interface Configuration
This section provides the configuration example to configure the GRE tunnel interface and associate a VRF with GRE
interface:
configure
context <vpn_context_name>
ip interface <intfc_name> tunnel
ip vrf forwarding <vrf_name>
ip address <internal_ip_address/mask>
tunnel-mode gre
source interface <non_tunn_intfc_to_corp>
destination address <global_ip_address>
keepalive interval <value> num-retry <retry>
end
Notes:
 <vpn_context_name > is the name of the system context you want to use for GRE interface configuration. For
more information, refer Command Line Interface Reference.
 A maximum of 511 GRE tunnels + 1 non-tunnel interface can be configured in one context. System needs at
least 1 non-tunnel interface as a default.
 <intfc_name > is name of the IP interface which is defined as a tunnel type interface and to be used for GRE
tunnel interface.
 <vrf_name > is the name of the VRF which is preconfigured in context configuration mode.
 <internal_ip_address/mask> is the network IP address with sub-net mask to be used for VRF forwarding.
 <non_tunn_intfc_to_corp > is the name a non-tunnel interface which is required by system as source
interface and preconfigured. For more information on interface configuration refer System Administration
Guide.
 <global_ip_address > is a globally reachable IP address to be used as a destination address.
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Enabling OSPF for VRF
This section provides the configuration example to enable the OSPF for VRF to support GRE tunnel interface:
configure
context <vpn_context_name>
router ospf
ip vrf <vrf_name>
network <internal_ip_address/mask>
end
Notes:
 <vpn_context_name > is the name of the system context you want to use for OSPF routing. For more
information, refer Routing in this guide.
 <vrf_name > is the name of the VRF which is preconfigured in context configuration mode.
 <internal_ip_address/mask > is the network IP address with sub-net mask to be used for OSPF routing.
Associating IP Pool and AAA Group with VRF
This section provides the configuration example for associating IP pool and AAA groups with VRF:
configure
context <vpn_context_name>
ip pool <ip_pool_name> <internal_ip_address/mask> vrf <vrf_name>
exit
aaa group <aaa_server_group>
ip vrf <vrf_name>
end
Notes:
 <vpn_context_name > is the name of the system context you want to use for IP pool and AAA server grou p.
 <ip_pool_name > is name of a preconfigured IP pool. For more information refer System Administration Guide.
 <aaa_server_group > is name of a preconfigured AAA server group. For more information refer AAA
Interface Administrtion and Reference.
 <vrf_name > is the name of the VRF which is preconfigured in context configuration mode.
 <internal_ip_address/mask > is the network IP address with sub-net mask to be used for IP pool.
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Associating APN with VRF
This section provides the configuration example for associating an APN with VRF through AAA group and IP pool:
configure
context <vpn_context_name>
apn <apn_name>
aaa group <aaa_server_group>
ip address pool name <ip_pool_name>
end
Notes:
 <vpn_context_name > is the name of the system context you want to use for APN configuration.
 <ip_pool_name > is name of a preconfigured IP pool. For more information refer System Administration Guide.
 <aaa_server_group > is name of a preconfigured AAA server group. For more information refer AAA
Interface Administrtion and Reference.
 <vrf_name > is the name of the VRF which is preconfigured in context configuration mode.
Static Route Configuration
This section provides the optional configuration example for configuring static routes when the route to the server is not
learnt from the corporate over OSPFv2:
configure
context <vpn_context_name>
ip route <internal_ip_address/mask> tunnel <tunnel_intfc_name> vrf <vrf_name>
end
Notes:
 <vpn_context_name > is the name of the system context you want to use for static route configuration.
 <internal_ip_address/mask > is the network IP address with sub-net mask to be used as static route.
 <tunnel_intfc_name > is name of a predefined tunnel type IP interface which is to be used for GRE tunnel
interface.
 <vrf_name > is the name of the VRF which is preconfigured in context configuration mode.
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▀ Verifying Your Configuration
Verifying Your Configuration
This section explains how to display and review the configurations after saving them in a .cfg file as described in the
System Administration Guide and also to retrieve errors and warnings within an active configuration for a service.
Important: All commands listed here are under Exec mode. Not all commands are available on all platforms.
These instructions are used to verify the GRE interface configuration.
Step 1
Verify that your interfaces are configured properly by entering the following command in Exec Mode:
show ip interface
The output of this command displays the configuration of the all interfaces configured in a context.
Intf Name:
foo1
Intf Type:
Broadcast
Description:
IP State:
UP (Bound to 17/2 untagged, ifIndex 285343745)
IP Address:
1.1.1.1
Subnet Mask:
255.255.255.0
Bcast Address:
1.1.1.255
MTU:
1500
Resoln Type:
ARP
ARP timeout:
60 secs
L3 monitor LC-port switchover: Disabled
Number of Secondary Addresses: 0
Intf Name:
foo2
Intf Type:
Tunnel (GRE)
Description:
VRF:
vrf-tun
IP State:
UP (Bound to local address 1.1.1.1 (foo1), remote
address 5.5.5.5)
IP Address:
10.1.1.1
Intf Name:
foo3
Intf Type:
Tunnel (GRE)
Subnet Mask:
255.255.255.0
Description:
IP State:
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Verifying Your Configuration ▀
IP Address:
Step 2
20.20.20.1
Subnet Mask:
255.255.255.0
Verify that GRE keep alive is configured properly by entering the following command in Exec Mode:
show ip interface gre-keepalive
The output of this command displays the configuration of the keepalive for GRE interface configured in a
context.
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Appendix D
Gx Interface Support
This chapter provides information on configuring Gx interface to support policy and charging control for subscribers.
The IMS service provides application support for transport of voice, video, and data independent of access su pport.
Roaming IMS subscribers require apart from other functionality sufficient, uninterrupted, consistent, and seamless user
experience during an application session. It is also important that a subscriber gets charged only for the resources
consumed by the particular IMS application used.
It is recommended that before using the procedures in this chapter you select the configuration example that best meets
your service model, and configure the required elements for that model as described in this Administration Guide.
The following topics are covered in this chapter:
 Rel. 6 Gx Interface
 Rel. 7 Gx Interface
 Rel. 8 Gx Interface
 Rel. 9 Gx Interface
 Assume Positive for Gx
 Time Reporting Over Gx
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▀ Rel. 6 Gx Interface
Rel. 6 Gx Interface
Rel. 6 Gx interface support is available on the Cisco ASR chassis running StarOS 8.0 and later releases for the
following products:
 GGSN
 IPSG
Important: In 14.0 and later releases, Rel. 6 Gx interface functionality is not supported on the chassis.
This section describes the following topics:
 Introduction
 How it Works
 Configuring Rel. 6 Gx Interface
Introduction
In GPRS/UMTS networks, the client functionality lies with the GGSN/IPSG, therefore in the IMS authorization
scenario it is also called Access Gateway (AGW).
The provisioning of charging rules that are based on the dynamic analysis of flows used for the IMS session is carried
out over the Gx interface. In 3GPP, Rel. 6 the Gx is an interface between Access Gateway functioning as Traffic Plane
Function (TPF) and the Charging Rule Function (CRF). It is based on the Diameter Base Protocol (DIABASE) and the
Diameter Credit Control Application (DCCA) standard. The GGSN/TPF acts as the client where as the CRF contains
the Diameter server functionality.
The AGW is required to perform query, in reply to which the servers provision certain policy or rules that are enforced
at the AGW for that particular subscriber session. The CRF analyzes the IP flow data, which in turn has been retrieved
from the Session Description Protocol (SDP) data exchanged during IMS session establishment.
Important: In addition to standard Gx interface functionality, the Gx interface implemented here provides
support of SBLP with additional AVPs in custom DPCA dictionaries. For more information on customer-specific
support contact your Cisco account representative. In view of required flow bandwidth and QoS, the system provides
enhanced support for use of Service Based Local Policy (SBLP) to provision and control the resources used by the IMS
subscriber. SBLP is based on the dynamic parameters such as the media/traffic flows for data transport, network
conditions and static parameters, such as subscriber configuration and category. It also provides Flow-based Charging
(FBC) mechanism to charge the subscriber dynamically based on content usage. With this additional functionality, the
Cisco Systems Gateway can act as an Enhanced Policy Decision Function (E-PDF).
Supported Networks and Platforms
This feature is supported on all chassis with StarOS Release 8.0 or later running GGSN service for the core network
services.
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Rel. 6 Gx Interface ▀
License Requirements
The Rel. 6 Gx interface support is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.
Supported Standards
The Rel 6. Gx interface support is based on the following standards and request for comments (RFCs):
 3GPP TS 29.210, Charging rule provisioning over Gx interface
Important: Note that Charging rule provisioning over Gx interface functionality is not
supported in 14.0 and later releases.
 RFC 3588, Diameter Base Protocol; September 2003
 RFC 4006, Diameter Credit-Control Application; August 2005
In addition to the above RFCs and standards, IMS Authorization partially supports 3GPP TS 29.212 for Policy and
Charging Control over Gx reference point functionality.
How it Works
This section describes the IMS authorization and dynamic policy support in GPRS/UMTS networks.
The following figure and table explain the IMS authorization process between a system and IMS components that is
initiated by the MN.
In the case of GGSN, the DPCA is the Gx interface to the Control and Charging Rule Function (CRF). In this context
CRF will act as Enhanced Policy Decision Function (E-PDF). The CRF may reside in Proxy-Call Session Control
Function (P-CSCF) or on stand-alone system.
The interface between IMSA with CRF is the Gx interface, and between Session Manager and Online Charging Service
(OCS) is the Gy interface.
Note that the IMS Authorization (IMSA) service and Diameter Policy Control Application (DPCA) are part of Session
Manager on the system, and separated in the following figure for illustration purpose only.
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Figure 37. Rel. 6 Gx IMS Authorization Call Flow
Table 22.
Rel. 6 Gx IMS Authorization Call flow Description
Step
Description
1
IMS subscriber (MN) sends request for primary PDP context activation/creation.
2
Session manager allocates IP address to MN.
3
Session manager sends IMS authorization request to IMS Authorization service (IMSA).
4
IMSA creates a session with the CRF on the basis of CRF configuration.
5
IMSA sends request to DPCA module to issue the authorization request to selected CRF.
6
DPCA sends a CCR-initial message to the selected CRF. This message includes the IP address allocated to MN.
7
CCA message sent to DPCA. If a preconfigured rule set for the PDP context is provided in CRF, it sends that charging
rules to DPCA in CCA message.
8
DPCA module calls the callback function registered with it by IMSA.
9
After processing the charging rules, IMSA sends Policy Authorization Complete message to session manager.
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Step
Description
10
The rules received in CCA message are used for dynamic rule configuration structure and session manager sends the
message to ECS.
11
ECS installs the rules and performs credit authorization by sending CCR-Initial to Online Charging System (OCS) with
CC-Request-Type set to INITIAL_REQUEST to open the credit control session. This request includes the active rule base
ID and 3GPP specific attributes (for example, APN, QoS and so on).
12
OCS returns a CCA-Initial message to activate the statically configured rulebase and includes preemptive credit quotas.
13
ECS responds to session manager with the response message for dynamic rule configuration.
14
On the basis of response for the PDP context authorization, Session Manager sends the response to the MN and
activates/rejects the call.
Configuring Rel. 6 Gx Interface
To configure Rel. 6 Gx interface functionality:
Step 1
Configure the IMS Authorization Service at the context level for an IMS subscriber in GPRS/UMTS network as
described in the Configuring IMS Authorization Service at Context Level section.
Step 2
Verify your configuration, as described in the Verifying IMS Authorization Service Configuration section.
Step 3
Configure an APN within the same context to use the IMS Authorization service for an IMS subscriber as described in
the Applying IMS Authorization Service to an APN section.
Step 4
Verify your configuration as described in the Verifying Subscriber Configuration section.
Step 5
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Important: Commands used in the configuration examples in this section provide base functionality to
the extent that the most common or likely commands and/or keyword options are presented. In many cases,
other optional commands and/or keyword options are available. Refer to the Command Line Interface
Reference for complete information regarding all commands.
Configuring IMS Authorization Service at Context Level
Use the following example to configure IMS Authorization Service at context level for IMS subscribers in
GPRS/UMTS networks:
configure
context <context_name>
ims-auth-service <imsa_service_name>
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p-cscf table { 1 | 2 } row-precedence <precedence_value> { address <ip_address>
| ipv6-address <ipv6_address> }
p-cscf discovery { table { 1 | 2 } [ algorithm { ip -address-modulus | msisdnmodulus | round-robin } ] | diameter-configured }
policy-control
diameter origin endpoint <endpoint_name>
diameter dictionary <dictionary>
failure-handling cc-request-type { any-request | initial-request | terminaterequest | update-request } { diameter-result-code { any-error | <result_code> [ to
<end_result_code> ] } } { continue | retry-and-terminate | terminate }
diameter host-select row-precedence <precedence_value> table { 1 | 2 } host
<host_name> [ realm <realm_name> ] [ secondary host <host_name> [ realm <realm_name> ] ]
diameter host-select reselect subscriber-limit <subscriber_limit> timeinterval <duration>
diameter host-select table { 1 | 2 } algorithm { ip -address-modulus | msisdnmodulus | round-robin }
end
Notes:
 <context_name> must be the name of the context where you want to enable IMS Authorization Service.
 <imsa_service_name> must be the name of the IMS Authorization Service to be configured for the Gx
interface authentication.
 A maximum of 16 authorization services can be configured globally in a system. There is also a system limit for
maximum number of total configured services.
 Secondary P-CSCF IP address can be configured in the P-CSCF table. Refer to the Command Line Interface
Reference for more information on the p-cscf table command.
 To enable Rel. 6 Gx interface support, specific Diameter dictionary must be configured. For information on the
Diameter dictionary to use, contact your Cisco account representative.
 Optional: To configure the quality of service (QoS) update timeout for a subscriber, in the IMS Authorization
Service Configuration Mode, enter the following command:
qos-update-timeout <timeout_duration>
Important: This command is obsolete in release 11.0 and later releases.
 Optional: To configure signalling restrictions, in the IMS Authorization Service Configuration Mode, enter the
following commands:
signaling-flag { deny | permit }
signaling-flow permit server-address <ip_address> [ server-port { <port_number> |
range <start_number> to <end_number> } ] [ description <string> ]
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 Optional: To configure action on packets that do not match any policy gates in the general purpose PDP context,
in the IMS Authorization Service Configuration Mode, enter the following command:
traffic-policy general-pdp-context no-matching-gates direction { downlink | uplink
} { forward | discard }
 Optional: To configure the algorithm to select Diameter host table, in the Policy Control Configuration Mode,
enter the following command:
diameter host-select table { 1 | 2 } algorithm { ip -address-modulus | msisdnmodulus | round-robin }
Verifying IMS Authorization Service Configuration
To verify the IMS Authorization Service configuration:
Step 1
Change to the context where you enabled IMS Authorization Service by entering the following command:
context <context_name>
Step 2
Verify the IMS Authorization Service’s configurations by entering the following command:
show ims-authorization service name <imsa_service_name>
Applying IMS Authorization Service to an APN
After configuring IMS Authorization service at the context-level, an APN must be configured to use the IMS
Authorization service for an IMS subscriber.
Use the following example to apply IMS Authorization service functionality to a previously configured APN within the
context configured in the Configuring IMS Authorization Service at Context Level section.
configure
context <context_name>
apn <apn_name>
ims-auth-service <imsa_service_name>
end
Notes:
 <context_name> must be the name of the context in which the IMS Authorization service was configured.
 <imsa_service_name> must be the name of the IMS Authorization Service configured for IMS authentication
in the context.
Verifying Subscriber Configuration
Verify the IMS Authorization Service configuration for subscriber(s) by entering the following command:
show subscribers ims-auth-service <imsa_service_name>
<imsa_service_name> must be the name of the IMS Authorization Service configured for IMS authentication.
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Rel. 7 Gx Interface
Rel. 7 Gx interface support is available on the Cisco ASR chassis running StarOS 8.1 or StarOS 9.0 and later releases
for the following products:
 GGSN
 IPSG
This section describes the following topics:
 Introduction
 Terminology and Definitions
 How it Works
 Configuring Rel. 7 Gx Interface
 Gathering Statistics
Introduction
For IMS deployment in GPRS/UMTS networks the system uses Rel. 7 Gx interface for policy-based admission control
support and flow-based charging. The Rel. 7 Gx interface supports enforcing policy control features like gating,
bandwidth limiting, and so on, and also supports flow-based charging. This is accomplished via dynamically
provisioned Policy Control and Charging (PCC) rules. These PCC rules are used to identify Service Data Flows (SDF)
and do charging. Other parameters associated with the rules are used to enforce policy control.
The PCC architecture allows operators to perform service-based QoS policy, and flow-based charging control. In the
PCC architecture, this is accomplished mainly by the Policy and Charging Enforcement Function (PCEF)/Cisco
Systems GGSN and the Policy and Charging Rules Function (PCRF).
In GPRS/UMTS networks, the client functionality lies with the GGSN, therefore in the IMS authorization scenario it is
also called the Gateway. In the following figure, Gateway is the Cisco Systems GGSN, and the PCEF function is
provided by Enhanced Charging Service (ECS). The Rel 7. Gx interface is implemented as a Diameter connection. The
Gx messages mostly involve installing/modifying/removing dynamic rules and activating/deactivating predefined rules.
The Rel. 7 Gx reference point is located between the Gateway and the PCRF. This reference point is used for
provisioning and removal of PCC rules from the PCRF to the Gateway, and the transmission of traffic plane events from
the Gateway to the PCRF. The Gx reference point can be used for charging control, policy control, or both by applying
AVPs relevant to the application. The following figure shows the reference points between various elements involved in
the policy and charging architecture.
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Figure 38.
PCC Logical Architecture
Within the Gateway, the IMSA and DPCA modules handle the Gx protocol related functions (at the SessMgr) and the
policy enforcement and charging happens at ECS. The Gy protocol related functions are handled within the DCCA
module (at the ECS). The following figure shows the interaction between components within the Gateway.
Figure 39.
PCC Architecture within Cisco PCEF
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Supported Networks and Platforms
This feature is supported on all chassis with StarOS Release 8.1 and later running GGSN service for the core network
services.
License Requirements
The Rel. 7 Gx interface support is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.
Supported Standards
The Rel 7. Gx interface support is based on the following standards and RFCs:
 3GPP TS 23.203 V7.6.0 (2008-03): 3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects; Policy and charging control architecture (Release 7)
 3GPP TS 29.212 V7.8.0 (2009-03): 3rd Generation Partnership Project; Technical Specification Group Core
Network and Terminals; Policy and Charging Control over Gx reference point (Release 7)
 3GPP TS 29.213 V7.4.0 (2008-03): 3rd Generation Partnership Project; Technical Specification Group Core
Network and Terminals; Policy and Charging Control signalling flows and QoS parameter mapping; (Release
7)
 RFC 3588, Diameter Base Protocol; September 2003
 RFC 4006, Diameter Credit-Control Application; August 2005
Terminology and Definitions
This section describes features and terminology pertaining to Rel. 7 Gx functionality.
Policy Control
The process whereby the PCRF indicates to the PCEF how to control the IP-CAN bearer.
Policy control comprises the following functions:
 Binding: Binding is the generation of an association between a Service Data Flow (SDF) and the IP CAN bearer
(for GPRS a PDP context) transporting that SDF.
The QoS demand in the PCC rule, as well as the SDF template are input for the bearer binding. The selected
bearer will have the same QoS Class as the one indicated by the PCC rule.
Depending on the type of IP-CAN and bearer control mode, bearer binding can be executed either by the
PCRF, or both PCRF and PCEF.
 For UE-only IP-CAN bearer establishment mode, the PCRF performs bearer binding. When the PCRF
performs bearer binding, it indicates the bearer (PDP context) by means of Bearer ID. The Bearer ID
uniquely identifies the bearer within the PDP session.
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 For UE/NW IP-CAN bearer establishment mode, the PCRF performs the binding of the PCC rules for
user controlled services, while the PCEF performs the binding of the PCC rules for the network controlled services.
 Gating Control: Gating control is the blocking or allowing of packets, belonging to an SDF, to pass through to
the desired endpoint. A gate is described within a PCC rule and gating control is applied on a per SDF basis.
The commands to open or close the gate leads to the enabling or disabling of th e passage for corresponding IP
packets. If the gate is closed, all packets of the related IP flows are dropped. If the gate is opened, the packets
of the related IP flows are allowed to be forwarded.
 Event Reporting: Event reporting is the notification of and reaction to application events to trigger new
behavior in the user plane as well as the reporting of events related to the resources in the Gateway (PCEF).
 Event triggers may be used to determine which IP-CAN session modification or specific event causes
the PCEF to re-request PCC rules. Although event trigger reporting from PCEF to PCRF can apply for
an IP CAN session or bearer depending on the particular event, provisioning of event triggers will be
done at session level.
Note that in 11.0 and later releases, RAR with unknown event triggers are silently ignored and
responded with DIAMETER_SUCCESS. In earlier releases, when unknown event triggers were
received in the RAR command from PCRF, invalid AVP result code was set in the RAA command.
 The Event Reporting Function (ERF) receives event triggers from PCRF during the Provision of PCC
Rules procedure and performs event trigger detection. When an event matching the received event
trigger occurs, the ERF reports the occurred event to the PCRF. If the prov ided event triggers are
associated with certain parameter values then the ERF includes those values in the response back to
the PCRF. The Event Reporting Function is located in the PCEF.
In StarOS releases prior to 14.0, SUCCESSFUL_RESOURCE_ALLOCATION ( 22 ) event trigger
was sent for rules irrespective of successful installation. In 14.0 and later releases,
SUCCESSFUL_RESOURCE_ALLOCATION ( 22 ) event trigger will be sent under the following
conditions:
 When a rule is installed successfully (and the event trigger is armed by PCRF and resourceallocation-notification is enabled).
 On partial failure, i.e. , when two or more rules are installed and at least one of the rules were
successfully installed. (and the event trigger is armed by PCRF and resource-allocationnotification is enabled).
On complete failure, i.e., none of the rules were installed, the event-trigger
SUCCESSFUL_RESOURCE_ALLOCATION ( 22 ) will not be sent.
Important: In this release, event triggers “IP-CAN_CHANGE” and
“MAX_NR_BEARERS_REACHED” are not supported.
 QoS Control: QoS control is the authorization and enforcement of the maximum QoS that is authorized for a
SDF or an IP-CAN bearer or a QoS Class Identifier (QCI). In case of an aggregation of multiple SDFs (for
GPRS a PDP context), the combination of the authorized QoS information of the individual SDFs is provided
as the authorized QoS for this aggregate.
 QoS control per SDF allows the PCC architecture to provide the PCEF with the authorized QoS to be
enforced for each specific SDF.
 The enforcement of the authorized QoS of the IP-CAN bearer may lead to a downgrading or upgrading
of the requested bearer QoS by the Gateway (PCEF) as part of a UE-initiated IP-CAN bearer
establishment or modification. Alternatively, the enforcement of the authorized QoS may, depending
on operator policy and network capabilities, lead to network-initiated IP-CAN bearer establishment or
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modification. If the PCRF provides authorized QoS for both, the IP-CAN bearer and PCC rule(s), the
enforcement of authorized QoS of the individual PCC rules takes place first.
 QoS authorization information may be dynamically provisioned by the PCRF, or it can be a predefined
PCC rule in the PCEF. In case the PCRF provides PCC rules dynamically, authorized QoS
information for the IP-CAN bearer (combined QoS) may be provided. For a predefined PCC rule
within the PCEF, the authorized QoS information takes affect when the PCC rule is activated. The
PCEF combines the different sets of authorized QoS information, that is the information received
from the PCRF and the information corresponding to the predefined PCC rules. The PCRF knows the
authorized QoS information of the predefined PCC rules and takes this information into account when
activating them. This ensures that the combined authorized QoS of a set of PCC rules that are
activated by the PCRF is within the limitations given by the subscription and operator policies
regardless of whether these PCC rules are dynamically provided, predefined, or both.
Important: In this release, QoS Resource Reservation is not supported.
Supported Features:
 Provisioning and Policy Enforcement of Authorized QoS: The PCRF may provide authorized QoS to the PCEF.
The authorized QoS provides appropriate values for resources to be enforced.
 Provisioning of “Authorized QoS” Per IP CAN Bearer: The authorized QoS per IP-CAN bearer is used if the
bearer binding is performed by the PCRF.
 Policy Enforcement for “Authorized QoS” per IP CAN Bearer: The PCEF is responsible for enforcing the
policy-based authorization, that is to ensure that the requested QoS is in-line with the “Authorized QoS” per IP
CAN Bearer.
 Policy Provisioning for Authorized QoS Per SDF: The provisioning of authorized QoS per SDF is a part of PCC
rule provisioning procedure.
 Policy Enforcement for Authorized QoS Per SDF: If an authorized QoS is defined for a PCC rule, the
PCEF limits the data rate of the SDF corresponding to that PCC rule not to exceed the maximum
authorized bandwidth for the PCC rule by discarding packets exceeding the limit.
 Upon deactivation or removal of a PCC rule, the PCEF frees the resources reserved for that PCC rule. If
the PCRF provides authorized QoS for both the IP-CAN bearer and PCC rule(s), the enforcement of
authorized QoS of the individual PCC rules takes place first.
Important: In this release, coordination of authorized QoS scopes in mixed mode (BCM = UE_NW) is not
supported.
 Provisioning of Authorized QoS Per QCI: If the PCEF performs the bearer binding, the PCRF may
provision an authorized QoS per QCI for non-GBR bearer QCI values. If the PCRF performs the
bearer binding the PCRF does not provision an authorized QoS per QCI. The PCRF does not
provision an authorized QoS per QCI for GBR bearer QCI values.
 Policy Enforcement for Authorized QoS per QCI: The PCEF can receive an authorized QoS per QCI
for non GBR-bearer QCI values.
 Other Features:
 Bearer Control Mode Selection: The PCEF may indicate, via the Gx reference point, a request for
Bearer Control Mode (BCM) selection at IP-CAN session establishment or IP-CAN session
modification (as a consequence of an SGSN change). It will be done using the “PCC Rule Request”
procedure.
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If the Bearer-Control-Mode AVP is not received from PCRF, the IP-CAN session is not terminated.
The value negotiated between UE/SGSN/GGSN is considered as the BCM. The following values are
considered for each of the service types:
 GGSN: The negotiated value between UE/SGSN/GGSN is considered.
In the following scenarios UE_ONLY is chosen as the BCM:
Scenario 1:
 UE-> UE_ONLY
 SGSN-> UE_ONLY
 GGSN-> UE_ONLY
 PCRF-> NO BCM
Scenario 2:
 UE-> UE_ONLY
 SGSN-> UE_ONLY
 GGSN-> Mixed
 PCRF-> NO BCM
 GTP-PGW: BCM of UE_NW is considered.
 IPSG: BCM of UE_ONLY is considered.
 HSGW/SGW/PDIF/FA/PDSN/HA/MIPV6HA: BCM of NONE is considered.
 PCC Rule Error Handling: If the installation/activation of one or more PCC rules fails, the PCEF
includes one or more Charging-Rule-Report AVP(s) in either a CCR or an RAA command for the
affected PCC rules. Within each Charging-Rule-Report AVP, the PCEF identifies the failed PCC
rule(s) by including the Charging-Rule-Name AVP(s) or Charging-Rule-Base-Name AVP(s),
identifies the failed reason code by including a Rule-Failure-Code AVP, and includes the PCC-RuleStatus AVP.
If the installation/activation of one or more new PCC rules (that is, rules that were not previously
successfully installed) fails, the PCEF sets the PCC-Rule-Status to INACTIVE for both the PUSH and
the PULL modes.
If a PCC rule was successfully installed/activated, but can no longer be enforced by the PCEF, the
PCEF sends the PCRF a new CCR command and include a Charging-Rule-Report AVP. The PCEF
includes the Rule-Failure-Code AVP within the Charging-Rule-Report AVP and sets the PCC-RuleStatus to INACTIVE.
 Time of the Day Procedures: PCEF performs PCC rule request as instructed by the PCRF.
Revalidation-Time when set by the PCRF, causes the PCEF to trigger a PCRF interaction to request
PCC rules from the PCRF for an established IP CAN session. The PCEF stops the timer once the
PCEF triggers a REVALIDATION_TIMEOUT event.
Important: In 11.0 and later releases, Rule-Activation-Time / Rule-Deactivation-Time / Revalidation-Time AVP
is successfully parsed only if its value corresponds to current time or a later time than the current IPSG time, else the
AVP and entire message is rejected. In earlier releases the AVP is successfully parsed only if its value corresponds to a
later time than the current IPSG time, else the AVP and entire message is rejected.
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Charging Control
Charging Control is the process of associating packets belonging to a SDF to a charging key, and applying online
charging and/or offline charging, as appropriate. Flow-based charging handles differentiated charging of the bearer
usage based on real time analysis of the SDFs. In order to allow for charging control, the information in the PCC rule
identifies the SDF and specifies the parameters for charging control. The PCC rule information may depend on
subscription data.
In the case of online charging, it is possible to apply an online charging action upon PCEF events (for example, re authorization upon QoS change).
It is possible to indicate to the PCEF that interactions with the charging systems are not required for a PCC rule, that is
to perform neither accounting nor credit control for this SDF, and then no offline charging information is generated.
Supported Features:
 Provisioning of Charging-related Information for the IP-CAN Session.
 Provisioning of Charging Addresses: Primary or secondary event charging function name (Online Charging
Server (OCS) addresses or the peer names).
Important: In this release, provisioning of primary or secondary charging collection function
name (Offline Charging Server (OFCS) addresses) over Gx is not supported.
 Provisioning of Default Charging Method: In this release, the default charging method is sent in CCR-I message.
For this, new AVPs Online/Offline are sent in CCR-I message based on the configuration.
Charging Correlation
For the purpose of charging correlation between SDF level and application level (for example, IMS) as well as on -line
charging support at the application level, applicable charging identifiers and IP-CAN type identifiers are passed from
the PCRF to the AF, if such identifiers are available.
For IMS bearer charging, the IP Multimedia Core Network (IM CN) subsystem and the Packet Switched (PS) domain
entities are required to generate correlated charging data.
In order to achieve this, the Gateway provides the GGSN Charging Identifier (GCID) associated with the PDP context
along with its address to the PCRF. The PCRF in turn sends the IMS Charging Identifier (ICID), which is provided by
the P-CSCF, to the Gateway. The Gateway generates the charging records including the GCID as well as the ICID if
received from PCRF, so that the correlation of charging data can be done with the billing system.
PCRF also provides the flow identifier, which uniquely identifies an IP flow in an IMS session.
Policy and Charging Control (PCC) Rules
A PCC rule enables the detection of an SDF and provides parameters for policy control and/or charging control. The
purpose of the PCC rule is to:
 Detect a packet belonging to an SDF.
 Select downlink IP CAN bearers based on SDF filters in the PCC rule.
 Enforce uplink IP flows are transported in the correct IP CAN bearer using the SDF filters within the
PCC rule.
 Identify the service that the SDF contributes to.
 Provide applicable charging parameters for an SDF.
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 Provide policy control for an SDF.
The PCEF selects a PCC rule for each packet received by evaluating received packets against SDF filters of PCC rules
in the order of precedence of the PCC rules. When a packet matches a SDF filter, the packet matching process for that
packet is completed, and the PCC rule for that filter is applied.
There are two types of PCC rules:
 Dynamic PCC Rules: Rules dynamically provisioned by the PCRF to the PCEF via the Gx interface. These PCC
rules may be either predefined or dynamically generated in the PCRF. Dynamic PCC rules can be installed,
modified, and removed at any time.
 Predefined PCC Rule: Rules preconfigured in the PCEF by the operators. Predefined PCC rules can be activated
or deactivated by the PCRF at any time. Predefined PCC rules within the PCEF may be grouped allowing the
PCRF to dynamically activate a set of PCC rules over the Gx reference point.
Important: A third type of rule, the static PCC rule can be preconfigured in the chassis by the operators. Static
PCC rules are not explicitly known in the PCRF, and are not under control of the PCRF. Static PCC rules are bound to
general purpose bearer with no Gx control.
A PCC rule consists of:
 Rule Name: The rule name is used to reference a PCC rule in the communication between the PCEF and PCRF.
 Service Identifier: The service identifier is used to identify the service or the service component the SDF re lates
to.
 Service Data Flow Filter(s): The service flow filter(s) is used to select the traffic for which the rule applies.
 Precedence: For different PCC rules with overlapping SDF filter, the precedence of the rule determines which of
these rules is applicable. When a dynamic PCC rule and a predefined PCC rule have the same priority, the
dynamic PCC rule takes precedence.
 Gate Status: The gate status indicates whether the SDF, detected by the SDF filter(s), may pass (gate is open) or
will be discarded (gate is closed) in uplink and/or in downlink direction.
 QoS Parameters: The QoS information includes the QoS class identifier (authorized QoS class for the SDF), the
Allocation and Retention Priority (ARP), and authorized bitrates for uplink and downlink.
Important: In earlier releases, ECS used only the Priority-Level part of ARP byte for bearer
binding, (along with QCI). Now the entire ARP byte is used for bearer binding (along with QCI).
Since the capability and vulnerability bits are optional in a dynamic rule, if a dynamic rule is
received without these flags, it is assumed that the capability bit is set to 1 (disabled) and
vulnerability bit is set to 0 (enabled). For predefined rules, currently configuring these two flags is
not supported, so as of now all predefined rules are assumed to have capability bit set to 1 (disabled)
and vulnerability bit set to 0 (enabled).
 Charging key (rating group)
 Other charging parameters: The charging parameters define whether online and offline charging interfaces are
used, what is to be metered in offline charging, on what level the PCEF will report the usage related to the rule,
and so on.
Important: In this release, configuring the Metering Method and Reporting Level for dynamic PCC rules is not
supported.
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PCC rules also include Application Function (AF) record information for enabling charging correlation between the
application and bearer layer if the AF has provided this information via the Rx interface. For IMS, this includes the IMS
Charging Identifier (ICID) and flow identifiers.
In releases prior to 14.0, there were only 10 PCC rules that were recovered per bearer in the event of a session manager
crash. In 14.0 and later releases, this limit has been increased to 24. That is, up to 24 PCC rules can be recovere d post
ICSR.
With the increase in the limit of PCC rules that can be recovered, the rules are not lost and hence the charging applied to
the end users are not impacted.
PCC Procedures over Gx Reference Point
Request for PCC rules
The PCEF, via the Gx reference point, requests for PCC rules in the following instances:
 At IP-CAN session establishment.
 At IP-CAN session modification.
PCC rules can also be requested as a consequence of a failure in the PCC rule installation/activation or enforcement
without requiring an event trigger.
Provisioning of PCC rules
The PCRF indicates, via the Rel. 7 Gx reference point, the PCC rules to be applied at the PCEF. This may be using one
of the following procedures:
 PULL (provisioning solicited by the PCEF): In response to a request for PCC rules being made by the PCEF, the
PCRF provisions PCC rules in the CC-Answer.
 PUSH (unsolicited provisioning): The PCRF may decide to provision PCC rules without obtaining a request
from the PCEF. For example, in response to information provided to the PCRF via the Rx reference point, or in
response to an internal trigger within the PCRF. To provision PCC rules without a request from the PCEF, the
PCRF includes these PCC rules in an RA-Request message. No CCR/CCA messages are triggered by this RARequest.
For each request from the PCEF or upon unsolicited provision the PCRF provisions zero o r more PCC rules. The PCRF
may perform an operation on a single PCC rule by one of the following means:
 To activate or deactivate a PCC rule that is predefined at the PCEF, the PCRF provisions a reference to this PCC
rule within a Charging-Rule-Name AVP and indicates the required action by choosing either the ChargingRule-Install AVP or the Charging-Rule-Remove AVP.
 To install or modify a PCRF-provisioned PCC rule, the PCRF provisions a corresponding Charging-RuleDefinition AVP within a Charging-Rule-Install AVP.
 To remove a PCC rule which has previously been provisioned by the PCRF, the PCRF provisions the name of
this rule as value of a Charging-Rule-Name AVP within a Charging-Rule-Remove AVP.
 If the PCRF performs the bearer binding, the PCRF may move previously installed or activated PCC rules from
one IP CAN bearer to another IP CAN bearer.
Important: In 11.0 and later releases, the maximum valid length for a charging rule name is 63 bytes. When the
length of the charging rule name is greater than 63 bytes, a charging rule report with RESOURCES_LIMITATION as
Rule-Failure-Code is sent. This charging rule report is sent only when the length of the rule name is lesser than 128
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characters. When the charging rule name length is greater than or equal to 128 characters no charging rule report will be
sent. In earlier releases, the length of the charging rule name constructed by PCRF was limited to 32 bytes.
Releases prior to 14.0, when PCRF has subscribed to Out of Credit trigger, on session connect when one rule validation
fails and also when an Out of Credit was received from OCS for another rule, P-GW was trying to report these failures
in different CCR-U to PCRF. However, the second CCR-U of Out of credit was getting dropped internally.
In 14.0 and later releases, on session connect, P-GW combines the rule failure and out of credit in the same CCR-U and
sends to PCRF.
Selecting a PCC Rule for Uplink IP Packets
If PCC is enabled, the PCEF selects the applicable PCC rule for each received uplink IP packet within an IP CAN
bearer by evaluating the packet against uplink SDF filters of PCRF-provided or predefined active PCC rules of this IP
CAN bearer in the order of the precedence of the PCC rules.
Important: When a PCRF-provided PCC rule and a predefined PCC rule have the same precedence, the uplink
SDF filters of the PCRF-provided PCC rule is applied first.
Important: In 11.0 and later releases, IMSA and ECS allow the PCRF to install two (or more) dynamic rules
with the same precedence value. In earlier releases, for two distinct dynamic rules having the same precedence the
second rule used to be rejected.
When a packet matches an SDF filter, the packet matching process for that packet is completed, and the PCC rule for
that filter is applied. Uplink IP packets which do not match any PCC rule of the corresponding IP CAN bearer are
discarded.
Selecting a PCC Rule and IP CAN Bearer for Downlink IP Packets
If PCC is enabled, the PCEF selects a PCC rule for each received downlink IP packet within an IP CAN session by
evaluating the packet against downlink SDF filters of PCRF-provided or predefined active PCC rules of all IP CAN
bearers of the IP CAN session in the order of the precedence of the PCC rules.
Important: When a PCRF-provided PCC rule and a predefined PCC rule have the same precedence, the
downlink SDF filters of the PCRF-provided PCC rule are applied first.
When a packet matches a SDF filter, the packet matching process for that packet is completed, and the PCC rule for that
filter is applied. The Downlink IP Packet is transported within the IP CAN bearer where the selected PCC rule is
mapped. Downlink IP packets that do not match any PCC rule of the IP CAN session are discarded.
The following procedures are also supported:
 Indication of IP-CAN Bearer Termination Implications
 Indication of IP-CAN Session Termination: When the IP-CAN session is being terminated (for example, for
GPRS when the last PDP Context within the IP-CAN session is being terminated) the PCEF contacts the
PCRF.
 Request of IP-CAN Bearer Termination: If the termination of the last IP CAN bearer within an IP CAN session
is requested, the PCRF and PCEF apply the “Request of IP-CAN Session Termination” procedure.
 Request of IP-CAN Session Termination: If the PCRF decides to terminate an IP CAN session due to an internal
trigger or trigger from the SPR, the PCRF informs the PCEF. The PCEF acknowledges to the PCRF and
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instantly removes/deactivates all the PCC rules that have been previously installed or activated on that IP-CAN
session.
The PCEF applies IP CAN specific procedures to terminate the IP CAN session. For GPRS, the GGSN send a PDP
context deactivation request with the teardown indicator set to indicate that the termination of the entire IP-CAN session
is requested. Furthermore, the PCEF applies the “Indication of IP CAN Session Termination” procedure.
In 12.0 and later releases, volume or rule information obtained from PCRF is discarded if the subscriber is going down.
Volume Reporting Over Gx
This section describes the 3GPP Rel. 9 Volume Reporting over Gx feature, which is supported by all products
supporting Rel. 7 Gx interface.
License Requirements
The Volume Reporting over Gx is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.
Important: In 12.0 and later releases, no separate license is required for Charging over Gx / Volume Reporting
over Gx feature. This feature can be enabled as part of "Policy Interface" license.
Supported Standards
The Volume Reporting over Gx feature is based on the following standard:
3GPP TS 29.212 V9.5.0 (2010-06): 3rd Generation Partnership Project; Technical Specification Group Core Network
and Terminals; Policy and Charging Control over Gx reference point (Release 9).
Feature Overview
The Volume Reporting over Gx feature provides PCRF the capability to make real-time decisions based on the data
usage by subscribers.
Important: Volume Reporting over Gx is applicable only for volume quota.
Important: In release 10.0, only total data usage reporting is supported, uplink/downlink level reporting is not
supported. In 10.2 and later releases, it is supported.
Important: The PCEF only reports the accumulated usage since the last report for usage monitoring and not from
the beginning.
Important: If the usage threshold is set to zero (infinite threshold), no further threshold events will be generated
by PCEF, but monitoring of usage will continue and be reported at the end of the session.
Important: In 12.2 and later releases, usage reporting on bearer termination is supported.
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The following steps explain how Volume Reporting over Gx works:
1. PCEF after receiving the message from PCRF parses the usage monitoring related AVPs, and sends the
information to IMSA.
2. IMSA updates the information to ECS.
3. Once the ECS is updated with the usage monitoring information from PCRF, the PCEF (ECS) starts tracking the
data usage.
4. For session-level monitoring, the ECS maintains the amount of data usage.
5. For PCC rule monitoring, usage is monitored with the monitoring key as the unique identifier. Each node
maintains the usage information per monitoring key. When the data traffic is passed, the usage is checked
against the usage threshold values and reported as described in the Usage Reporting section.
6. The PCEF continues to track data usage after the threshold is reached and before a new threshold is provided by
the PCRF. If a new usage threshold is not provided by the PCRF in the acknowledgement of an IP-CAN
Session modification where its usage was reported, then usage monitoring does not continue in the PCEF for
that IP CAN session.
Usage Monitoring
 Usage Monitoring at Session Level: PCRF subscribes to the session-level volume reporting over Gx by sending
the Usage-Monitoring-Information AVP with the usage threshold level set in Granted-Service-Unit AVP and
Usage-Monitoring-Level AVP set to SESSION_LEVEL(0). After the AVPs are parsed by DPCA, IMSA
updates the information to ECS. Once ECS is updated usage monitoring is started and constantly checked with
the usage threshold whenever the data traffic is present. In 11.0 and later releases, Monitoring Key at session
level is supported.
In 12.0 and later releases, enabling and disabling session usage in a single message from PCRF is supported.
This is supported only if the monitoring key is associated at session level.
In 12.0 and later releases, monitoring of usage based on input/output octet threshold levels is supported. Usage
is reported based on the enabled threshold level. If multiple levels are enabled, usage will be reported on all the
enabled levels even if only one of the levels is breached. Monitoring will be stopped on the missing threshold
levels in the response for the usage report from PCRF (expected to provide the complete set again if PCRF
wants to continue monitoring on the multiple levels enabled earlier).
Total threshold level along with UL/DL threshold level in the GSU AVP is treated as an error and only tot al
threshold level is accepted.
 Usage Monitoring at Flow Level: PCRF subscribes to the flow-level volume reporting over Gx by sending the
Usage-Monitoring-Information AVP with the usage threshold level set in Granted-Service-Unit AVP and
Usage-Monitoring-Level AVP set to PCC_RULE_LEVEL(1). Monitoring Key is mandatory in case of a flowlevel monitoring since the rules are associated with the monitoring key and enabling/disabling of usage
monitoring at flow level can be controlled by PCRF using it. After the AVPs are parsed by DPCA, IMSA
updates the information to ECS. Once ECS is updated usage monitoring is started and constantly checked with
the usage threshold whenever the data traffic is present.
Usage monitoring is supported for static, predefined rules, and dynamic rule definitions.
 Usage Monitoring for Static Rules: In the case of static rules, the usage reporting on last rule removal
associated with the monitoring key is not applicable. In this case only the usage monitoring
information is received from the PCRF.
 Usage Monitoring for Predefined Rules: If the usage monitoring needs to be enabled for the predefined
rules, PCRF sends the rule and the usage monitoring information containing the monitoring key and
the usage threshold. The Monitoring key should be same as the one pre-configured in PCEF for that
predefined rule. There can be multiple rules associated with the same monitoring key. Hence enabling
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a particular monitoring key would result in the data being tracked for multiple rules having the same
monitoring key. After DPCA parses the AVPs IMSA updates the information to ECS. Once ECS is
updated usage monitoring is started and constantly checked with the usage threshold whenever the
data traffic is present.
 Usage Monitoring for Dynamic Rules: If the usage monitoring needs to be enabled for dynamic
ruledefs, PCRF provides the monitoring key along with a charging rule definition and the usage
monitoring information containing the monitoring key and the usage threshold. This would result in
the usage monitoring being done for all the rules associated with that monitoring key. After DPCA
parses the AVPs, IMSA updates the information to ECS. Once ECS is updated, the usage monitoring
is started and constantly checked with the usage threshold whenever the data traffic is present.
Monitoring key for dynamic ruledef is dynamically assigned by PCRF which is the only difference
with predefined rules in case of usage monitoring.
In releases prior to 15.0, when threshold breach happens for multiple monitoring keys at the same time, only one of the
monitoring key’s usage is reported and the rest of the monitoring keys’ usage is reported in CCR-T (threshold set to
infinity). On Tx expiry/TCP link error, unreported usage is stored at ECS and reported only on session te rmination.
In 15.0 and later releases, only one of the monitoring key’s usage is reported first. Upon receiving successful response
from PCRF, the rest of the monitoring keys’ usage is reported to PCRF. On Tx expiry/TCP link error, unreported usage
is stored at ECS. Any future successful interaction with PCRF for the session will send unreported UMI to PCRF.
Usage Reporting
Usage at subscriber/flow level is reported to PCRF under the following conditions:
 Usage Threshold Reached: PCEF records the subscriber data usage and checks if the usage threshold provided
by PCRF is reached. This is done for both session and rule level reporting.
For session-level reporting, the actual usage volume is compared with the usage volume threshold.
For rule-level reporting the rule that hits the data traffic is used to find out if the monitoring key is associated
with it, and based on the monitoring key the data usage is checked. Once the condition is met, it reports the
usage information to IMSA and continues monitoring. IMSA then triggers the CCR-U if “USAGE_REPORT”
trigger is enabled by the PCRF. The Usage-Monitoring-Information AVP is sent in this CCR with the “UsedService-Unit” set to the amount of data usage by subscriber.
If PCRF does not provide a new usage threshold in the usage monitoring information as a result of CCR from
PCEF when the usage threshold is reached, the usage monitoring is stopped at PCEF and no usage status is
reported.
In the non-standard Volume Reporting over Gx implementation, usage monitoring will be stopped once the
threshold is breached, else the monitoring will continue. There will be no further usage reporting until the CCA
is received.
 Usage Monitoring Disabled: If the PCRF explicitly disables the usage monitoring with Usage-MonitoringSupport AVP set to USAGE_MONITORING_DISABLED, the PCEF stops monitoring and reports the usage
information (when the monitoring was enabled) to PCRF if the usage monitoring is disabled by PCRF as a
result of CCR from PCEF which is not related to reporting usage, other external triggers, or a PCRF internal
trigger. If the PCRF does not provide a new usage threshold as a result of CCR from PCEF when the usage
threshold is reached, the usage monitoring is stopped at PCEF and no further usage status is reported.
 IP CAN Session Termination: When the IP CAN session is terminated, the accumulated subscriber usage
information is reported to PCRF in the CCR-T from PCEF. If PCC usage level information is enabled by
PCRF, the PCC usage will also be reported.
 PCC Rule Removal: When the PCRF deactivates the last PCC rule associated with a usage monitoring key, the
PCEF sends a CCR with the data usage for that monitoring key. If the PCEF reports the last PCC rule
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associated with a usage monitoring key is inactive, the PCEF reports the accumulated usage for that monitoring
key within the same CCR command if the Charging-Rule-Report AVP was included in a CCR command;
otherwise, if the Charging-Rule-Report AVP was included in an RAA command, the PCEF sends a new CCR
command to report accumulated usage for the usage monitoring key. In 12.0 and later releases, usage reporting
on last rule deactivation using rule deactivation time set by PCRF is supported.
Releases prior to 14.0, when PCC rule was tried to be removed while waiting for access side update bearer
response, the charging rules were not removed. In 14.0 and later releases, on receiving message from PCRF,
the rule that is meant for removal is marked and then after the access side procedure is complete the rule is
removed.
 PCRF Requested Usage Report: In 10.2 and later releases, the accumulated usage since the last report is sent
even in case of immediate reporting, the usage is reset after immediate reporting and usage monitoring
continued so that the subsequent usage report will have the usage since the current report. In earlier releases the
behavior was to accumulate the so far usage in the next report.
 Release 12.2 onwards, usage reporting on bearer termination can be added. When a bearer is deleted due to some
reason, the rules associated with the bearer will also be removed. So, the usage will be reported on the
monitoring key(s) whose associated rule is the last one that is removed because of bearer termination.
 Revalidation Timeout: In the non-standard implementation, if usage monitoring and reporting is enabled and a
revalidation timeout occurs, the PCEF sends a CCR to request PCC rules and reports all accumulated usage for
all enabled monitoring keys since the last report (or since usage reporting was enabled if the usage was not yet
reported) with the accumulated usage at IP-CAN session level (if enabled) and at service data flow level (if
enabled) This is the default behavior.
In the case of standard implementation, this must be enabled by CLI configuration.
Important: The Usage Reporting on Revalidation Timeout feature is available by default in non-standard
implementation of Volume Reporting over Gx. In 10.2 and later releases, this is configurable in the standard
implementation. This is not supported in 10.0 release for standard based volume reporting.
Once the usage is reported, the usage counter is reset to zero. The PCEF continues to track data usage from the zero
value after the threshold is reached and before a new threshold is provided by the PCRF. If a new usage threshold is not
provided by the PCRF in the acknowledgement of an IP-CAN Session modification where its usage was reported, then
usage monitoring does not continue in the PCEF for that IP CAN session and and the usage accumulated between the
CCR-CCA will be discarded.
For information on how to configure the Volume Reporting over Gx feature, see the Configuring Volume Reporting
over Gx section.
ICSR Support for Volume Reporting over Gx (VoRoGx)
In releases prior to 15.0, post the ICSR switchover, any existing session for which the PCRF has enabled volume
reporting used to continue indefinitely until the session is terminated or until CCR-U is sent for a given trigger, without
having the volume counted via Gx.
To summarize, after an ICSR switchover, volume reporting over Gx is no longer done for existing sessions. Also,
volume usage is not synced to standby chassis.
In 15.0 and later releases, volume threshold and volume usage are synced to standby chassis to support volume
reporting over Gx for existing sessions post switchover.
Without this support it cannot cause a subscriber to use higher speeds than what s/he is supposed to get, if volume
reporting is for example used to enforce fair usage; the operator may already consider this a revenue loss. It will also
severely impact roaming subscribers who are supposed to get a notification and be blocked/redirected once the limits set
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by the EU roaming regulation are reached. If a session continues now without being blocked, the operator is not allowed
to charge for data beyond the limit and will have a significant and real revenue loss (roaming partner may still charge
for the data used on their SGSNs).
How Rel. 7 Gx Works
This section describes how dynamic policy and charging control for subscribers works with Rel. 7 Gx interface support
in GPRS/UMTS networks.
The following figure and table explain the IMSA process between a system and IMS components that is initiated by the
UE.
In this example, the Diameter Policy Control Application (DPCA) is the Gx interface to the PCRF. The interface
between IMSA with PCRF is the Gx interface, and the interface between Session Manager (SessMgr) and Online
Charging Service (OCS) is the Gy interface. Note that the IMSA service and DPCA are part of SessMgr on the system
and separated in the figure for illustration purpose only.
Important: In 14.0 and later releases, the DPCA and the IMSA will be acting as one module within the Policy
Server interface application.
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Figure 40.
Rel. 7 Gx IMS Authorization Call Flow
Table 23.
Rel. 7 Gx IMS Authorization Call flow Description
Step
Description
1
UE (IMS subscriber) requests for primary PDP context activation/creation.
2
SessMgr allocates an IP address to the UE.
3
SessMgr requests IMS Authorization, if IMSA is enabled for the APN.
4
IMSA allocates resources for the IP CAN session and the bearer, and selects the PCRF to contact based on the user's
selection key (for example, msisdn).
5
IMSA requests the DPCA module to issue an auth request to the PCRF.
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Step
Description
6
DPCA sends a CCR initial message to the selected PCRF. This message includes the Context-Type AVP set to PRIMARY
and the IP address allocated to the UE. The message may include the Bearer-Usage AVP set to GENERAL. The BearerOperation is set to Establishment. The Bearer ID is included if the PCRF does the bearer binding.
7
PCRF may send preconfigured charging rules in CCA, if a preconfigured rule set for general purpose PDP context is
provided in PCRF. The dynamic rules and the authorized QoS parameters could also be included by the PCRF.
8
DPCA passes the charging rule definition, charging rule install, QoS information received from the PCRF, event triggers,
and so on, along with the Bearer ID that corresponds to the rules received from the PCRF to IMSA. IMSA stores the
information. If the Bearer ID is absent, and PCRF does the bearer binding, the rule is skipped. Whereas, if the Bearer ID is
absent and the PCEF does the bearer binding, the rule is passed onto the ECS to perform bearer binding.
9
DPCA calls the callback function registered with it by IMSA.
10
IMSA stores the bearer authorized QoS information and notifies the SessMgr. Other PCRF provided information common
to the entire PDP session (event trigger, primary/secondary OCS address, and so on) is stored within the IMSA. After
processing the information, IMSA notifies the SessMgr about the policy authorization complete.
11
If the validation of the rules fails in IMSA/DPCA, a failure is notified to PCRF containing the Charging-Rule-Report AVP.
Else, IMSA initiates creation of ECS session. The APN name, primary/secondary OCS server address, and so on are sent to
the ECS from the SessMgr.
12
ECS performs credit authorization by sending CCR(I) to OCS with CC-Request-Type set to INITIAL_REQUEST to open
the credit control session. This request includes the active Rulebase-Id (default rulebase ID from the APN/AAA) and GPRS
specific attributes (for example, APN, UMTS QoS, and so on).
13
OCS returns a CCA initial message that may activate a statically configured Rulebase and may include preemptive quotas.
14
ECS responds to SessMgr with the response message.
15
SessMgr requests IMSA for the dynamic rules.
16
IMSA sends the dynamic rules to SessMgr.
Note that, in 14.0 and later releases, the RAR messages are allowed before the session is established. In earlier releases,
until the primary PDP context is established, all RAR messages from the PCRF were reject ed.
Also note that, in 14.0 and later releases, the RAR message is rejected and RAA is sent with 3002 result code when the
recovery of dynamic rule information and audit of Session Manager are in progress. Earlier, the RAR messages were
processed by DPCA even when the recovery audit was in progress.
17
SessMgr sends the dynamic rule information to the ECS. The gate flow status information and the QoS per flow (charging
rule) information are also sent in the message.
18
ECS activates the predefined rules received, and installs the dynamic rules received. Also, the gate flow status and the QoS
parameters are updated by ECS as per the dynamic charging rules. The Gx rulebase is treated as an ECS group-of-ruledefs.
The response message contains the Charging Rule Report conveying the status of the rule provisioning at the ECS. ECS
performs PCEF bearer binding for rules without bearer ID.
19
If the provisioning of rules fails partially, the context setup is accepted, and a new CCR-U is sent to the PCRF with the
Charging-Rule-Report containing the PCC rule status for the failed rules. If the provisioning of rules fails completely, the
context setup is rejected.
20
Depending on the response for the PDP Context Authorization, SessMgr sends the response to the UE an d activates/rejects
the call. If the Charging-Rule-Report contains partial failure for any of the rules, the PCRF is notified, and the call is
activated. If the Charging-Rule-Report contains complete failure, the call is rejected.
21
Based on the PCEF bearer binding for the PCC rules at Step 18, the outcome could be one or more network -initiated PDP
context procedures with the UE (Network Requested Update PDP Context (NRUPC) / Network Requested Secondary PDP
Context Activation (NRSPCA)).
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Configuring Rel. 7 Gx Interface
To configure Rel. 7 Gx interface functionality, the IMS Authorization service must be config ured at the context level,
and then the APN configured to use the IMS Authorization service.
To configure Rel. 7 Gx interface functionality:
Step 1
Configure IMS Authorization service at the context level for IMS subscriber in GPRS/UMTS network as described in
the Configuring IMS Authorization Service at Context Level section.
Step 2
Verify your configuration as described in the Verifying the Configuration section.
Step 3
Configure an APN within the same context to use the IMS Authorization service for IMS subscriber as described in the
Applying IMS Authorization Service to an APN section.
Step 4
Verify your configuration as described in the Verifying Subscriber Configuration section.
Step 5
Optional: Configure the Volume Reporting over Gx feature as described in the Configuring Volume Reporting over Gx
section.
Step 6
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Important: Commands used in the configuration examples in this section provide base functionality to
the extent that the most common or likely commands and/or keyword options are presented. In many cases,
other optional commands and/or keyword options are available. Refer to the Command Line Interface
Reference for complete information regarding all commands.
Configuring IMS Authorization Service at Context Level
Use the following example to configure IMS Authorization service at context level for IMS subscribers in GPRS/UMTS
networks:
configure
context <context_name>
ims-auth-service <imsa_service_name>
p-cscf discovery table { 1 | 2 } algorithm { ip -address-modulus | msisdn-modulus
| round-robin }
p-cscf table { 1 | 2 } row-precedence <precedence_value> { address <ip_address>
| ipv6-address <ipv6_address> } [ secondary { address <ip_address> | ipv6-address
<ipv6_address> } ]
policy-control
diameter origin endpoint <endpoint_name>
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diameter dictionary <dictionary>
diameter request-timeout <timeout_duration>
diameter host-select table { { { 1 | 2 } algorithm { ip -address-modulus |
msisdn-modulus | round-robin } } | prefix-table { 1 | 2 } }
diameter host-select row-precedence <precedence_value> table { { { 1 | 2 }
host <host_name> [ realm <realm_id> ] [ secondary host <host_name> [ realm <realm_id> ] ]
} | { prefix-table { 1 | 2 } msisdn-prefix-from <msisdn_prefix_from> msisdn-prefix-to
<msisdn_prefix_to> host <host_name> [ realm <realm_id> ] [ secondary host <sec_host_name>
[ realm <sec_realm_id> ] algorithm { active-standby | round-robin } ] } } [ -noconfirm ]
diameter host-select reselect subscriber-limit <subscriber_limit> timeinterval <duration>
failure-handling cc-request-type { any-request | initial-request | terminaterequest | update-request } { diameter-result-code { any-error | <result_code> [ to
<end_result_code> ] } } { continue | retry-and-terminate | terminate }
end
Notes:
 <context_name> must be the name of the context where you want to enable IMS Authorization service.
 <imsa_service_name> must be the name of the IMS Authorization service to be configured for Rel. 7 Gx
interface authentication.
 A maximum of 16 authorization services can be configured globally in a system. There is also a system limit for
the maximum number of total configured services.
 To enable Rel. 7 Gx interface support, pertinent Diameter dictionary must be configured. For information on the
specific Diameter dictionary to use, contact your Cisco account representative.
 When configuring the MSISDN prefix range based PCRF selection mechanism:
To enable the Gx interface to connect to a specific PCRF for a range of subscribers configure msisdnprefix-from <msisdn_prefix_from> and msisdn-prefix-to <msisdn_prefix_to> with the
starting and ending MSISDNs respectively.
To enable the Gx interface to connect to a specific PCRF for a specific subscriber, configure both msisdnprefix-from <msisdn_prefix_from> and msisdn-prefix-to <msisdn_prefix_to> with the same
MSISDN.
In StarOS 8.1 and later releases, per MSISDN prefix range table a maximum of 128 rows can be added. In
StarOS 8.0 and earlier releases, a maximum of 100 rows can be added.
The MSISDN ranges must not overlap between rows.
 The Round Robin algorithm for PCRF selection is effective only over a large number of PCRF selections, and
not at a granular level.
 Optional: To configure the Quality of Service (QoS) update timeout for a subscriber, in the IMS Authorization
Service Configuration Mode, enter the following command:
qos-update-timeout <timeout_duration>
Important: This command is obsolete in release 11.0 and later releases.
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 Optional: To configure signalling restrictions, in the IMS Authorization Service Configuration Mode, enter the
following commands:
signaling-flag { deny | permit }
signaling-flow permit server-address <ip_address> [ server-port { <port_number> |
range <start_number> to <end_number> } ] [ description <string> ]
 Optional: To configure action on packets that do not match any policy gates in the general purpose PDP context,
in the IMS Authorization Service Configuration Mode, enter the following command:
traffic-policy general-pdp-context no-matching-gates direction { downlink | uplink
} { forward | discard }
 To configure the PCRF host destinations configured in the GGSN/PCEF, use the diameter host-select CLI
commands.
 To configure the GGSN/PCEF to use a pre-defined rule when the Gx fails, set the failure-handling ccrequest-type CLI to continue. Policies available/in use will continue to be used and there will be no
further interaction with the PCRF.
 For provisioning of default charging method, use the following configurations. For this, the AVPs Online and
Offline will be sent in CCR-I message based on the configuration.
 To send Enable Online:
configure
active-charging service <ecs_service_name>
charging-action <charging_action_name>
cca charging credit
exit
 To send Enable Offline:
configure
active-charging service <ecs_service_name>
rulebase <rulebase_name>
billing-records rf
exit
Verifying the Configuration
To verify the IMS Authorization service configuration:
Step 1
Change to the context where you enabled IMS Authorization service by entering the following command:
context <context_name>
Step 2
Verify the IMS Authorization service’s configurations by entering the following command:
show ims-authorization service name <imsa_service_name>
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Applying IMS Authorization Service to an APN
After configuring IMS Authorization service at the context-level, an APN must be configured to use the IMS
Authorization service for an IMS subscriber.
Use the following example to apply IMS Authorization service functionality to a previously configured APN within the
context configured in the Configuring Rel. 7 Gx Interface section.
configure
context <context_name>
apn <apn_name>
ims-auth-service <imsa_service_name>
active-charging rulebase <rulebase_name>
end
Notes:
 <context_name> must be the name of the context in which the IMS Authorization service was configured.
 <imsa_service_name> must be the name of the IMS Authorization service configured for IMS authentication
in the context.
 For Rel. 7 Gx, the ECS rulebase must be configured in the APN.
 ECS allows change of rulebase via Gx for PCEF binding scenarios. When the old rulebase goes away, all the
rules that were installed from that rulebase are removed. This may lead to termination of a few bearers (PDP
contexts) if they are left without any rules. If there is a Gx message that changes the rulebase, and also
activates some predefined rules, the rulebase change is made first, and the rules are activated from the new
rulebase. Also, the rulebase applies to the entire call. All PDP contexts (bearers) in one call use the same ECS
rulebase.
 For predefined rules configured in the ECS, MBR/GBR of a dynamic/predefined rule is checked before it is used
for PCEF binding. All rules (dynamic as well as predefined) have to have an MBR associated with them and all
rules with GBR QCI should have GBR also configured. So for predefined rules, one needs to configure
appropriate peak-data-rate, committed-data-rate as per the QCI being GBR QCI or non-GBR QCI. For more
information, in the ACS Charging Action Configuration Mode, see the flow limit-for-bandwidth CLI
command.
 Provided interpretation of the Gx rulebase is chosen to be ECS group-of-ruledefs, in the Active Charging Service
Configuration Mode configure the following command:
policy-control charging-rule-base-name active-charging-group-of-ruledefs
Verifying Subscriber Configuration
Verify the IMS Authorization service configuration for subscriber(s) by entering the following command:
show subscribers ims-auth-service <imsa_service_name>
<imsa_service_name> must be the name of the IMS Authorization service configured for IMS authentication.
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Configuring Volume Reporting over Gx
This section describes the configuration required to enable Volume Reporting over Gx.
To enable Volume Reporting over Gx, use the following configuration:
configure
active-charging service <ecs_service_name>
rulebase <rulebase_name>
action priority <priority> dynamic-only ruledef <ruledef_name> charging-action
<charging_action_name> monitoring-key <monitoring_key>
exit
exit
context <context_name>
ims-auth-service <imsa_service_name>
policy-control
event-update send-usage-report [ reset-usage ]
end
Notes:
 The maximum accepted monitoring key value by the PCEF is 4294967295. If the PCEF sends a greater value,
the value is converted to an Unsigned Integer value.
 The event-update CLI which enables volume usage report to be sent in event updates is available only in 10.2
and later releases. The optional keyword reset-usage enables to support delta reporting wherein the usage is
reported and reset at PCEF. If this option is not configured, the behavior is to send the usage information as
part of event update but not reset at PCEF.
Gathering Statistics
This section explains how to gather Rel. 7 Gx statistics and configuration information.
In the following table, the first column lists what statistics to gather, and the second column lists the action to perform.
Table 24.
Gathering Rel. 7 Gx Statistics and Information
Statistics/Information
Action to perform
Information and statistics specific to policy control in IMS
Authorization service.
show ims-authorization policy-control
statistics
Information and statistics specific to the authorization servers used for
IMS Authorization service.
show ims-authorization servers ims-authservice
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Statistics/Information
Action to perform
Information of all IMS Authorization service.
show ims-authorization service all
Statistics of IMS Authorization service.
show ims-authorization service statistics
Information, configuration, and statistics of sessions active in IMS
Authorization service.
show ims-authorization sessions all
Complete information, configuration, and statistics of sessions active in
IMS Authorization service.
show ims-authorization sessions full
Summarized information of sessions active in IMS Authorization
service.
show ims-authorization sessions summary
Complete statistics for active charging service sessions.
show active-charging sessions full
Information for all rule definitions configured in the service.
show active-charging ruledef all
Information for all rulebases configured in the system.
show active-charging rulebase all
Information on all group of ruledefs configured in the system.
show active-charging group-of-ruledefs
all
Information on policy gate counters and status.
show ims-authorization policy-gate {
counters | status }
This command is no longer an option in StarOS release
11.0 and beyond.
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Rel. 8 Gx Interface
Rel. 8 Gx interface support is available on the Cisco ASR chassis running StarOS 10.0 or StarOS 11.0 and later releases.
This section describes the following topics:
 HAPDSN Rel. 8 Gx Interface Support
 P-GW Rel. 8 Gx Interface Support
HA/PDSN Rel. 8 Gx Interface Support
This section provides information on configuring Rel. 8 Gx interface for HA and PDSN to support policy and charging
control for subscribers in CDMA networks.
The IMS service provides application support for transport of voice, video, and data independent of access support.
Roaming IMS subscribers in CDMA networks require apart from other functionality sufficient, uninterrupted,
consistent, and seamless user experience during an application session. It is also important that a subscriber gets charged
only for the resources consumed by the particular IMS application used.
It is recommended that before using the procedures in this section you select the configuration example that best meets
your service model, and configure the required elements for that model as described in this Administration Guide.
This section describes the following topics:
 Introduction
 Terminology and Definitions
 How it Works
 Configuring HA/PDSN Rel. 8 Gx Interface Support
 Gathering Statistics
Introduction
For IMS deployment in CDMA networks the system uses Rel. 8 Gx interface for policy-based admission control
support and flow-based charging (FBC). The Rel. 8 Gx interface supports enforcing policy control features like gating,
bandwidth limiting, and so on, and also supports FBC. This is accomplished via dynamically provisioned Policy Control
and Charging (PCC) rules. These PCC rules are used to identify Service Data Flows (SDF) and to do charging. Other
parameters associated with the rules are used to enforce policy control.
The PCC architecture allows operators to perform service-based QoS policy and FBC control. In the PCC architecture,
this is accomplished mainly by the Policy and Charging Enforcement Function (PCEF)/HA/PDSN and the Policy and
Charging Rules Function (PCRF). The client functionality lies with the HA/PDSN, therefore in the IMS Authorization
(IMSA) scenario it is also called the Gateway. The PCEF function is provided by the Enhanced Charging Service
(ECS). The Gx interface is implemented as a Diameter connection. The Gx messaging mostly involves
installing/modifying/removing dynamic rules and activating/deactivating predefined rules.
The Gx reference point is located between the Gateway/PCEF and the PCRF. This reference point is used for
provisioning and removal of PCC rules from the PCRF to the Gateway/PCEF, and the transmission of traffic plane
events from the Gateway/PCEF to the PCRF. The Gx reference point can be used for charging control, policy control, or
both by applying AVPs relevant to the application.
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The following figure shows the reference points between elements involved in the policy and charging architecture.
Figure 41.
HA/PDSN Rel. 8 Gx PCC Logical Architecture
Within the Gateway, the IMSA and DPCA modules handle the Gx protocol related functions (at the SessMgr) and the
policy enforcement and charging happens at ECS. The Gy protocol related functions are handled within the DCCA
module (at the ECS).
The following figure shows the interaction between components within the Gateway.
Figure 42.
HA/PDSN Rel. 8 Gx PCC Architecture within PCEF
License Requirements
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The HA/PDSN Rel. 8 Gx interface support is a licensed Cisco feature. A separate feature license may be required.
Contact your Cisco account representative for detailed information on specific licensing requirements. For information
on installing and verifying licenses, refer to the Managing License Keys section of the Software Management
Operations chapter in the System Administration Guide.
Supported Standards
HA/PDSN Rel 8. Gx interface support is based on the following standards and RFCs:
 3GPP TS 23.203 V8.3.0 (2008-09) 3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects; Policy and charging control architecture (Release 8)
 3GPP TS 29.212 V8.6.0 (2009-12) 3rd Generation Partnership Project; Technical Specification Group Core
Network and Terminals; Policy and Charging Control over Gx reference point (Release 8)
 3GPP TS 29.213 V8.1.1 (2008-10) 3rd Generation Partnership Project; Technical Specification Group Core
Network and Terminals; Policy and Charging Control signalling flows and QoS parameter mapping; (Release
8)
 RFC 3588, Diameter Base Protocol; September 2003
 RFC 4006, Diameter Credit-Control Application; August 2005
Terminology and Definitions
This section describes features and terminology pertaining to HA/PDSN Rel. 8 Gx functionality.
Policy Control
The process whereby the PCRF indicates to the PCEF how to control the IP-CAN session.
Policy control comprises the following functions:
 Binding
 Gating Control
 Event Reporting
 QoS Control
 Other Features
Binding
In the HA/PDSN Rel. 8 Gx implementation, since there are no bearers within a MIP session the IP-CAN Bearer concept
does not apply. Only authorized IP-CAN session is applicable.
Gating Control
Gating control is the blocking or allowing of packets belonging to an SDF, to pass through to the desired endpoint. A
gate is described within a PCC rule and gating control is applied on a per SDF basis. The commands to open or close the
gate leads to the enabling or disabling of the passage for corresponding IP packets. If the gate is closed, all packets of
the related IP flows are dropped. If the gate is open, the packets of the related IP flows are allowed to be forwarded.
Event Reporting
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Important: Unconditional reporting of event triggers from PCRF to PCEF when PCEF has not requested for is
not supported.
Important: In the HA/PDSN Rel. 8 Gx implementation, only the AN_GW_CHANGE (21) event trigger is
supported.
Event reporting is the notification of and reaction to application events to trigger new behavior in the user plane as well
as the reporting of events related to the resources in the Gateway (PCEF). Event triggers may be used to determine
which IP-CAN session modification or specific event causes the PCEF to re-request PCC rules. Event trigger reporting
from PCEF to PCRF, and provisioning of event triggers happens at IP-CAN session level.
The Event Reporting Function (ERF) located in the PCEF, receives event triggers from PCRF during the Provision of
PCC Rules procedure and performs event trigger detection. When an event matching the received event trigger occurs,
the ERF reports the occurred event to the PCRF. If the provided event triggers are associated with certain parameter
values then the ERF includes those values in the response to the PCRF.
QoS Control
Important: In the HA/PDSN Rel. 8 Gx implementation, only authorized IP-CAN Session is supported.
Provisioning of authorized QoS per IP-CAN bearer, policy enforcement for authorized QoS per QCI, and coordination
of authorized QoS scopes in mixed mode are not applicable.
QoS control is the authorization and enforcement of the maximum QoS that is authorized for an SDF. In case of an
aggregation of multiple SDFs, the combination of the authorized QoS information of the individual SDFs is provided as
the authorized QoS for this aggregate. QoS control per SDF allows the PCC architecture to provide the PCEF with the
authorized QoS to be enforced for each specific SDF.
QoS authorization information may be dynamically provisioned by the PCRF, or it can be a predefined PCC rule in the
PCEF. For a predefined PCC rule within the PCEF, the authorized QoS information takes affect when the PCC rule is
activated. The PCEF combines the different sets of authorized QoS information, that is the information received from
the PCRF and the information corresponding to the predefined PCC rules. The PCRF knows the authorized QoS
information of the predefined PCC rules and takes this information into account when activating th em. This ensures that
the combined authorized QoS of a set of PCC rules that are activated by the PCRF is within the limitations given by the
subscription and operator policies regardless of whether these PCC rules are dynamically provided, predefined, or both.
Supported features include:
 Provisioning and Policy Enforcement of Authorized QoS: The PCRF may provide authorized QoS to the PCEF.
The authorized QoS provides appropriate values for resources to be enforced.
 Policy Provisioning for Authorized QoS Per SDF: The provisioning of authorized QoS per SDF is a part of PCC
rule provisioning procedure.
 Policy Enforcement for Authorized QoS Per SDF: If an authorized QoS is defined for a PCC rule, the PCEF
limits the data rate of the SDF corresponding to that PCC rule not to exceed the maximum authorized
bandwidth for the PCC rule by discarding packets exceeding the limit.
 Upon deactivation or removal of a PCC rule, the PCEF frees the resources reserved for that PCC rule.
Other Features
This section describes some of the other features.
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PCC Rule Error Handling
If the installation/activation of one or more PCC rules fails, the PCEF communicates the failure to the PCRF by
including one or more Charging-Rule-Report AVP(s) in either a CCR or an RAA command for the affected PCC rules.
Within each Charging-Rule-Report AVP, the PCEF identifies the failed PCC rule(s) by including the Charging-RuleName AVP(s) or Charging-Rule-Base-Name AVP(s), identifies the failed reason code by including a Rule-Failure-Code
AVP, and includes the PCC-Rule-Status AVP.
If the installation/activation of one or more new PCC rules (that is, rules that were not previously successfully installed)
fail, the PCEF sets the PCC-Rule-Status to INACTIVE for both the PUSH and the PULL modes.
If a PCC rule was successfully installed/activated, but can no longer be enforced by the PCEF, the PCEF sends the
PCRF a new CCR command and includes the Charging-Rule-Report AVP. The PCEF includes the Rule-Failure-Code
AVP within the Charging-Rule-Report AVP and sets the PCC-Rule-Status to INACTIVE.
In the HA/PDSN Gx implementation, the following rule failure codes are supported:
 RATING_GROUP_ERROR (2)
 SERVICE_IDENTIFIER_ERROR (3)
 GW/PCEF_MALFUNCTION (4)
 RESOURCES_LIMITATION (5)
If the installation/activation of one or more PCC rules fails during RAR procedure, the RAA command is sent with the
Experimental-Result-Code AVP set to DIAMETER_PCC_RULE_EVENT (5142).
Time of the Day Procedures
PCEF performs PCC rule request as instructed by the PCRF. Revalidation-Time when set by the PCRF, causes the
PCEF to trigger a PCRF interaction to request PCC rules from the PCRF for an established IP-CAN session. The PCEF
stops the timer once the PCEF triggers a REVALIDATION_TIMEOUT event.
When installed, the PCC rule is inactive. If Rule-Activation-Time / Rule-Deactivation-Time is specified, then the PCEF
sets the rule active / inactive after that time.
Charging Control
Important: In the HA/PDSN Rel. 8 Gx implementation, offline charging is not supported.
Charging Control is the process of associating packets belonging to an SDF to a charging key, and applying online
charging as appropriate. FBC handles differentiated charging of the bearer usage based on real -time analysis of the
SDFs. In order to allow for charging control, the information in the PCC rule identifies the SDF and specifies the
parameters for charging control. The PCC rule information may depend on subscription data.
Online charging is supported via the Gy interface. In the case of online charging, it is possible to apply an online
charging action upon PCEF events (for example, re-authorization upon QoS change).
It is possible to indicate to the PCEF that interactions with the charging systems are not required for a PCC rule, that is
to perform neither accounting nor credit control for this SDF, then neither online nor offline charging is performed.
Supported Features:
 Provisioning of charging-related information for the IP-CAN Session
 Provisioning of charging addresses: Primary or secondary event charging function name (Online Charging
Server (OCS) addresses)
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Important: In the HA/PDSN Rel. 8 Gx implementation, provisioning of primary or
secondary charging collection function name (Offline Charging Server (OFCS) addresses) over Gx
is not supported.
 Provisioning of Default Charging Method
Charging Correlation
In the HA/PDSN Rel. 8 Gx implementation, Charging Correlation is not supported. PCRF provides the flow identifier,
which uniquely identifies an IP flow in an IMS session.
Policy and Charging Control (PCC) Rules
A PCC rule enables the detection of an SDF and provides parameters for policy control and/or charging control. The
purpose of the PCC rule is to:
 Detect a packet belonging to an SDF in case of both uplink and downlink IP flows based on SDF filters in the
PCC rule (packet rule matching).
If no PCC rule matches the packet, the packet is dropped.
 Identify the service that the SDF contributes to.
 Provide applicable charging parameters for an SDF.
 Provide policy control for an SDF.
The PCEF selects a PCC rule for each packet received by evaluating received packets against SDF filters of PCC rules
in the order of precedence of the PCC rules. When a packet matches an SDF filter, the packet matching process for that
packet is completed, and the PCC rule for that filter is applied.
There are two types of PCC rules:
 Dynamic PCC Rules: Rules dynamically provisioned by the PCRF to the PCEF via the Gx interface. These PCC
rules may be either predefined or dynamically generated in the PCRF. Dynamic PCC rules can be activated,
modified, and deactivated at any time.
 Predefined PCC Rule: Rules preconfigured in the PCEF by the operators. Predefined PCC rules can be activated
or deactivated by the PCRF at any time. Predefined PCC rules within the PCEF may be grouped allowing the
PCRF to dynamically activate a set of PCC rules over the Gx reference point.
Important: A third kind of rule, the static PCC rule can be preconfigured in the chassis by the operators. Static
PCC rules are not explicitly known in the PCRF, and are not under control of the PCRF. Static PCC rules are bound to
general purpose bearer with no Gx control.
A PCC rule consists of:
 Rule Name: The rule name is used to reference a PCC rule in the communication between the PCEF and PCRF.
 Service Identifier: The service identifier is used to identify the service or the service component the SDF relates
to.
 Service Data Flow Filter(s): The service flow filter(s) is used to select the traffic for which the rule applies.
 Precedence: For different PCC rules with overlapping SDF filter, the precedence of the rule determines which of
these rules is applicable. When a dynamic PCC rule and a predefined PCC rule have the same priority, the
dynamic PCC rule takes precedence.
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 Gate Status: The gate status indicates whether the SDF, detected by the SDF filter(s), may pass (gate is open) or
will be discarded (gate is closed) in uplink and/or in downlink direction.
 QoS Parameters: The QoS information includes the QoS class identifier (authorized QoS class for the SDF), and
authorized bitrates for uplink and downlink.
 Charging Key (rating group)
 Other charging parameters: The charging parameters define whether online charging interfaces are used, on what
level the PCEF will report the usage related to the rule, etc.
Important: Configuring the Metering Method and Reporting Level for dynamic PCC rules is not supported.
PCC rules also include Application Function (AF) record information for enabling charging correlation between the
application and bearer layer if the AF has provided this information via the Rx interface. For IMS, this includes the IMS
Charging Identifier (ICID) and flow identifiers.
In releases prior to 14.0, there were only 10 PCC rules that were recovered per bearer in the event of a session manager
crash. In 14.0 and later releases, this limit has been increased to 24. That is, up to 24 PCC rules can be recovered post
ICSR.
With the increase in the limit of PCC rules that can be recovered, the rules are not lost and hence the charging applied to
the end users are not impacted.
PCC Procedures over Gx Reference Point
Request for PCC Rules
The PCEF, via the Gx reference point, requests for PCC rules in the following instances:
 At IP-CAN session establishment
 At IP-CAN session modification
PCC rules can also be requested as a consequence of a failure in the PCC rule installation/activation or enforcement
without requiring an event trigger.
Provisioning of PCC Rules
The PCRF indicates, via the Rel. 8 Gx reference point, the PCC rules to be applied at the PCEF. This may be using one
of the following procedures:
 PULL (provisioning solicited by the PCEF): In response to a request for PCC rules being made by the PCEF, the
PCRF provisions PCC rules in the CC-Answer.
 PUSH (unsolicited provisioning): The PCRF may decide to provision PCC rules without obtaining a request
from the PCEF. For example, in response to information provided to the PCRF via the Rx reference point, or in
response to an internal trigger within the PCRF. To provision PCC rules without a request from the PCEF, the
PCRF includes these PCC rules in an RA-Request message. No CCR/CCA messages are triggered by this RARequest.
For each request from the PCEF or upon unsolicited provisioning, the PCRF provisions zero or more PCC rules. The
PCRF may perform an operation on a single PCC rule by one of the following means:
 To activate or deactivate a PCC rule that is predefined at the PCEF, the PCRF provisions a reference to this PCC
rule within a Charging-Rule-Name AVP and indicates the required action by choosing either the ChargingRule-Install AVP or the Charging-Rule-Remove AVP.
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 To install or modify a PCRF-provisioned PCC rule, the PCRF provisions a corresponding Charging-RuleDefinition AVP within a Charging-Rule-Install AVP.
 To remove a PCC rule which has previously been provisioned by the PCRF, the PCRF provisions the name of
this rule as value of a Charging-Rule-Name AVP within a Charging-Rule-Remove AVP.
Important: In 11.0 and later releases, the maximum valid length for a charging rule name is 63 bytes. When the
length of the charging rule name is greater than 63 bytes, a charging rule report with RESOURCES_LIMITATION as
Rule-Failure-Code is sent. This charging rule report is sent only when the length of the rule name is lesser than 128
characters. When the charging rule name length is greater than or equal to 128 characters no charging rule report will be
sent. In earlier releases, the length of the charging rule name constructed by PCRF was limited to 32 bytes.
Releases prior to 14.0, when PCRF has subscribed to Out of Credit trigger, on session connect when one rule validation
fails and also when an Out of Credit was received from OCS for another rule, P-GW was trying to report these failures
in different CCR-U to PCRF. However, the second CCR-U of Out of credit was getting dropped internally.
In 14.0 and later releases, on session connect, P-GW combines the rule failure and out of credit in the same CCR-U and
sends to PCRF.
Selecting a PCC Rule for Uplink IP Packets
If PCC is enabled, the PCEF selects the applicable PCC rule for each received uplink IP packet within an IP-CAN
session by evaluating the packet against uplink SDF filters of PCRF-provided or predefined active PCC rules of this IPCAN session in the order of the precedence of the PCC rules.
Important: When a PCRF-provided PCC rule and a predefined PCC rule have the same precedence, the uplink
SDF filters of the PCRF-provided PCC rule is applied first.
When a packet matches an SDF filter, the packet matching process for that packet is completed, and the PCC rul e for
that filter is applied. Uplink IP packets which do not match any PCC rule of the corresponding IP-CAN session are
discarded.
Selecting a PCC Rule for Downlink IP Packets
If PCC is enabled, the PCEF selects a PCC rule for each received downlink IP packet within an IP-CAN session by
evaluating the packet against downlink SDF filters of PCRF-provided or predefined active PCC rules of the IP-CAN
session in the order of precedence of the PCC rules.
Important: When a PCRF-provided PCC rule and a predefined PCC rule have the same precedence, the
downlink SDF filters of the PCRF-provided PCC rule are applied first.
When a packet matches an SDF filter, the packet matching process for that packet is completed, and the PCC rule for
that filter is applied. Downlink IP packets that do not match any PCC rule of the IP-CAN session are discarded.
The following procedures are also supported:
 Indication of IP-CAN Session Termination: When the IP-CAN session is being terminated the PCEF contacts the
PCRF.
 Request of IP-CAN Session Termination: If the PCRF decides to terminate an IP-CAN session due to an internal
trigger or trigger from the SPR, the PCRF informs the PCEF. The PCEF acknowledges to the PCRF and
instantly removes/deactivates all the PCC rules that have been previously installed or activated on that IP-CAN
session.
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The PCEF applies IP-CAN specific procedures to terminate the IP-CAN session. The HA/PDSN sends a MIP
Revocation Request with the teardown indicator set to indicate that the termination of the entire IP-CAN
session is requested. Furthermore, the PCEF applies the “Indication of IP-CAN Session Termination”
procedure.
 Use of the Supported-Features AVP during session establishment to inform the destination host about the
required and optional features that the origin host supports.
How it Works
This section describes how HA/PDSN Rel. 8 Gx Interface support works.
The following figure and table explain the IMS Authorization process between a system and IMS components that is
initiated by the UE.
In this example, the Diameter Policy Control Application (DPCA) is the Gx interface to the PCRF. The interface
between IMSA with PCRF is the Gx interface, and the interface between Session Manager (SessMgr) and Online
Charging Service (OCS) is the Gy interface. Note that the IMSA service and DPCA are part of SessMgr on the system
and separated in the figure for illustration purpose only.
Important: In 14.0 and later releases, the DPCA and the IMSA will be acting as one module within the Policy
Server interface application.
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Figure 43.
HA/PDSN Rel. 8 Gx IMS Authorization Call Flow
Table 25. HA/PDSN Rel. 8 Gx IMS Authorization Call flow Description
Step
Description
1
UE (IMS subscriber) requests for MIP Registration Request.
2
SessMgr allocates an IP address to the UE.
3
SessMgr requests IMS Authorization, if IMSA is enabled for the subscriber.
IMSA service can either be configured in the subscriber template, or can be received from the AAA.
4
IMSA allocates resources for the IP-CAN session, and selects the PCRF to contact based on the user's selection key (for
example, round-robin).
5
IMSA requests the DPCA module to issue an auth request to the PCRF.
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Step
Description
6
DPCA sends a CCR initial message to the selected PCRF.
7
PCRF may send preconfigured charging rules in CCA. The dynamic rules and the authorized QoS parameters could also be
included by the PCRF.
8
DPCA passes the charging rule definition, charging rule install, QoS information received from the PCRF, event triggers,
etc. IMSA stores the information.
9
DPCA calls the callback function registered with it by IMSA.
10
PCRF-provided information common to the entire IP-CAN session (event trigger, primary/secondary OCS address, etc.) is
stored within the IMSA. After processing the information, IMSA notifies the SessMgr about the policy authorization
complete.
11
If the validation of the rules fails in IMSA/DPCA, a failure is notified to PCRF containing the Charging-Rule-Report AVP.
Else, IMSA initiates creation of ECS session. The primary/secondary OCS server address, etc. are sent to the ECS from the
SessMgr.
12
ECS performs credit authorization by sending CCR(I) to OCS with CC-Request-Type set to INITIAL_REQUEST to open
the credit control session. This request includes the active Rulebase-Id (default rulebase ID from the AAA).
13
OCS returns a CCA initial message that may activate a statically configured Rulebase and may include preemptive quotas.
14
ECS responds to SessMgr with the response message.
15
SessMgr requests IMSA for the dynamic rules.
16
IMSA sends the dynamic rules to SessMgr.
Note that, in 14.0 and later releases, the RAR messages are allowed before the session is established. In earlier releases,
until the MIP session is established, all RAR messages from the PCRF were rejected.
Also note that, in 14.0 and later releases, the RAR message is rejected and RAA is sent with 3002 result code when the
recovery of dynamic rule information and audit of Session Manager are in progress. Earlier, the RAR messages were
processed by DPCA even when the recovery audit was in progress.
17
SessMgr sends the dynamic rule information to the ECS. The gate flow status information and the QoS per flow (charging
rule) information are also sent in the message.
18
ECS activates the predefined rules received, and installs the dynamic rules received. Also, the gate flow status and the QoS
parameters are updated by ECS as per the dynamic charging rules. The Gx rulebase is treated as an ECS group-of-ruledefs.
The response message contains the Charging Rule Report conveying the status of the rule provisioning at the ECS.
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If the provisioning of rules fails partially, the context setup is accepted, and a new CCR-U is sent to the PCRF with the
Charging-Rule-Report containing the PCC rule status for the failed rules. If the provisioning of rules fails completely, the
context setup is rejected.
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Depending on the response for the MIP Session Authorization, SessMgr sends the response to the UE and activates/rejects
the call. If the Charging-Rule-Report contains partial failure for any of the rules, the PCRF is notified, and the call is
activated. If the Charging-Rule-Report contains complete failure, the call is rejected.
Configuring HA/PDSN Rel. 8 Gx Interface Support
To configure HA/PDSN Rel. 8 Gx Interface functionality:
1. At the context level, configure IMSA service for IMS subscribers as described in the Configuring IMS
Authorization Service at Context Level section.
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2. Within the same context, configure the subscriber template to use the IMSA service as described in the Applying
IMS Authorization Service to Subscriber Template section.
3. Save your configuration to flash memory, an external memory device, and/or a network location using the Exec
mode command save configuration . For additional information on how to verify and save configuration
files, refer to the System Administration Guide and the Command Line Interface Reference.
Important: Commands used in the configuration examples in this section provide base functionality to the extent
that the most common or likely commands and/or keyword options are presented. In many cases, other optional
commands and/or keyword options are available. Refer to the Command Line Interface Reference for complete
information regarding all commands.
Configuring IMS Authorization Service at Context Level
Use the following example to configure IMSA service at context level for IMS subscribers:
configure
context <context_name>
ims-auth-service <imsa_service_name>
policy-control
diameter origin endpoint <endpoint_name>
diameter dictionary <dictionary>
diameter request-timeout <timeout_duration>
diameter host-select table { 1 | 2 } algorithm round -robin
diameter host-select row-precedence <precedence_value> table { 1 | 2 } host
<primary_host_name> [ realm <primary_realm_id> ] [ secondary host <secondary_host_name> [
realm <secondary_realm_id> ] ] [ -noconfirm ]
failure-handling cc-request-type { any-request | initial-request | terminaterequest | update-request } { diameter-result-code { any-error | <result_code> [ to
<end_result_code> ] } } { continue | retry-and-terminate | terminate }
exit
exit
diameter endpoint <endpoint_name> [ -noconfirm ]
origin realm <realm_name>
use-proxy
origin host <host_name> address <ip_address>
no watchdog-timeout
response-timeout <timeout_duration>
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connection timeout <timeout_duration>
connection retry-timeout <timeout_duration>
peer <primary_peer_name> [ realm <primary_realm_name> ] address <ip_address> [
port <port_number> ]
peer <secondary_peer_name> [ realm <secondary_realm_name> ] address <ip_address>
[ port <port_number> ]
end
Notes:
 <context_name> must be the name of the context where you want to enable IMSA service.
 <imsa_service_name> must be the name of the IMSA service to be configured for Rel. 8 Gx interface
authentication.
 A maximum of 16 authorization services can be configured globally in a system. There is also a system limit for
the maximum number of total configured services.
 To enable Rel. 8 Gx interface support, pertinent Diameter dictionary must be configured. For info rmation on the
specific Diameter dictionary to use, contact your Cisco account representative.
 The Round Robin algorithm for PCRF selection is effective only over a large number of PCRF selections, and
not at a granular level.
 To configure the PCRF host destinations configured in the PCEF, use the diameter host-select CLI commands.
 To configure the PCEF to use a pre-defined rule when the Gx fails, set the failure-handling cc-requesttype CLI to continue . Policies available/in use will continue to be used and there will be no further
interaction with the PCRF.
Verifying the IMSA Service Configuration
To verify the IMSA service configuration:
 Change to the context where you enabled IMSA service by entering the following command:
context <context_name>
 Verify the IMSA service’s configuration by entering the following command:
show ims-authorization service name <imsa_service_name>
Applying IMS Authorization Service to Subscriber Template
After configuring IMSA service at the context-level, within the same context subscriber template must be configured to
use the IMSA service for IMS subscribers.
Use the following example to apply IMSA service functionality to subscriber template within the context previously
configured in the Configuring IMS Authorization Service at Context Level section.
configure
context <context_name>
subscriber default
encrypted password <encrypted_password>
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ims-auth-service <imsa_service_name>
ip access-group <access_group_name> in
ip access-group <access_group_name> out
ip context-name <context_name>
mobile-ip home-agent <ip_address>
active-charging rulebase <rulebase_name>
end
Notes:
 <context_name> must be the name of the context in which the IMSA service was configured.
 <imsa_service_name> must be the name of the IMSA service configured for IMS authentication in the
context.
 The ECS rulebase must be configured in the subscriber template.
 Provided interpretation of the Gx rulebase (Charging-Rule-Base-Name AVP) from PCRF is chosen to be ECS
group-of-ruledefs, configure the following command in the Active Charging Service Configuration Mode:
policy-control charging-rule-base-name active-charging-group-of- ruledefs
Verifying the Subscriber Configuration
Verify the IMSA service configuration for subscriber(s) by entering the following command in the Exec CLI
configuration mode:
show subscribers ims-auth-service <imsa_service_name>
Notes:
<imsa_service_name> must be the name of the IMSA service configured for IMS authentication.
Gathering Statistics
This section explains how to gather Rel. 8 Gx statistics and configuration information.
In the following table, the first column lists what statistics to gather, and the second column lists the action to perform.
Table 26. Gathering HA/PDSN Rel. 8 Gx Statistics and Information
Statistics/Information
Action to perform
Information and statistics specific to policy control in IMS
Authorization service.
show ims-authorization policy-control
statistics
Information and statistics specific to the authorization servers used for
IMS Authorization service.
show ims-authorization servers ims-authservice
Information of all IMS Authorization service.
show ims-authorization service all
Statistics of IMS Authorization service.
show ims-authorization service statistics
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Statistics/Information
Action to perform
Information, configuration, and statistics of sessions active in IMS
Authorization service.
show ims-authorization sessions all
Complete information, configuration, and statistics of sessions active in
IMS Authorization service.
show ims-authorization sessions full
Summarized information of sessions active in IMS Authorization
service.
show ims-authorization sessions summary
Complete statistics for active charging service sessions.
show active-charging sessions full
Information for all rule definitions configured in the service.
show active-charging ruledef all
Information for all rulebases configured in the system.
show active-charging rulebase all
Information on all group of ruledefs configured in the system.
show active-charging group-of-ruledefs
all
Information on policy gate counters and status.
show ims-authorization policy-gate {
counters | status }
This command is no longer an option in StarOS release
11.0 and beyond.
P-GW Rel. 8 Gx Interface Support
Introduction
The Gx reference point is located between the Policy and Charging Rules Function (PCRF) and the Policy and Charging
Enforcement Function (PCEF) on the Packet Data Network (PDN) Gateway (P-GW). The Gx reference point is used for
provisioning and removal of PCC rules from the PCRF to the PCEF and the transmission of traffic plane events from
the PCEF to the PCRF. The Gx reference point can be used for charging control, policy control, or both, by applying
AVPs relevant to the application.
The PCEF is the functional element that encompasses policy enforcement and flow based charging functionality. This
functional entity is located at the P-GW. The main functions include:
 Control over the user plane traffic handling at the gateway and its QoS.
 Service data flow detection and counting, as well as online and offline charging interactions.
 For a service data flow that is under policy control, the PCEF shall allow the service data flow to pass through
the gateway if and only if the corresponding gate is open.
 For a service data flow that is under charging control, the PCEF shall allow the service data flow to pass through
the gateway if and only if there is a corresponding active PCC rule and, for online charging, the OCS has
authorized the applicable credit with that charging key.
 If requested by the PCRF, the PCEF shall report to the PCRF when the status of the related service data flow
changes.
 In case the SDF is tunnelled at the BBERF, the PCEF shall inform the PCRF about the mobility protocol
tunnelling header of the service data flows at IP-CAN session establishment.
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Terminology and Definitions
This section describes features and terminology pertaining to Rel. 8 Gx functionality.
Volume Reporting Over Gx
This section describes the 3GPP Rel. 9 Volume Reporting over Gx feature.
License Requirements
The Volume Reporting over Gx is a licensed Cisco feature. A separate feature license may be required. C ontact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.
Important: In 12.0 and later releases, no separate license is required for Charging over Gx / Volume Reporting
over Gx feature. This feature can be enabled as part of "Policy Interface" license.
Supported Standards
The Volume Reporting over Gx feature is based on the following standard:
3GPP TS 29.212 V9.5.0 (2010-06): 3rd Generation Partnership Project; Technical Specification Group Core Network
and Terminals; Policy and Charging Control over Gx reference point (Release 9).
Feature Overview
The Volume Reporting over Gx feature provides PCRF the capability to make real-time decisions based on the data
usage by subscribers.
Important: Volume Reporting over Gx is applicable only for volume quota.
Important: In release 10.0, only total data usage reporting is supported, uplink/downlink level reporting is not
supported. In 10.2 and later releases, it is supported.
Important: The PCEF only reports the accumulated usage since the last report for usage monitoring and not from
the beginning.
Important: If the usage threshold is set to zero (infinite threshold), no further threshold events will be generated
by PCEF, but monitoring of usage will continue and be reported at the end of the session.
Important: In 12.2 and later releases, usage reporting on bearer termination is supported.
The following steps explain how Volume Reporting over Gx works:
1. PCEF after receiving the message from PCRF parses the usage monitoring related AVPs, and sends the
information to IMSA.
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2. IMSA updates the information to ECS.
3. Once the ECS is updated with the usage monitoring information from PCRF, the PCEF (ECS) starts tracking the
data usage.
4. For session-level monitoring, the ECS maintains the amount of data usage.
5. For PCC rule monitoring, usage is monitored with the monitoring key as the unique identifier. Each node
maintains the usage information per monitoring key. When the data traffic is passed, the usage is checked
against the usage threshold values and reported as described in the Usage Reporting section.
6. The PCEF continues to track data usage after the threshold is reached and before a new threshold is provided by
the PCRF. If a new usage threshold is not provided by the PCRF in the acknowledgement of an IP-CAN
Session modification where its usage was reported, then usage monitoring does not continue in the PCEF for
that IP CAN session.
Usage Monitoring
 Usage Monitoring at Session Level: PCRF subscribes to the session-level volume reporting over Gx by sending
the Usage-Monitoring-Information AVP with the usage threshold level set in Granted-Service-Unit AVP and
Usage-Monitoring-Level AVP set to SESSION_LEVEL(0). After the AVPs are parsed by DPCA, IMSA
updates the information to ECS. Once ECS is updated usage monitoring is started and constantly checked with
the usage threshold whenever the data traffic is present. In 11.0 and later releases, Monitoring Key at session
level is supported.
In 12.0 and later releases, enabling and disabling session usage in a single message from PCRF is supported.
This is supported only if the monitoring key is associated at session level.
In 12.0 and later releases, monitoring of usage based on input/output octet threshold levels is supported. Usage
is reported based on the enabled threshold level. If multiple levels are enabled, usage will be reported on all the
enabled levels even if only one of the levels is breached. Monitoring will be stopped on the missing threshold
levels in the response for the usage report from PCRF (expected to provide the complete set again if PCR F
wants to continue monitoring on the multiple levels enabled earlier).
Total threshold level along with UL/DL threshold level in the GSU AVP is treated as an error and only total
threshold level is accepted.
 Usage Monitoring at Flow Level: PCRF subscribes to the flow-level volume reporting over Gx by sending the
Usage-Monitoring-Information AVP with the usage threshold level set in Granted-Service-Unit AVP and
Usage-Monitoring-Level AVP set to PCC_RULE_LEVEL(1). Monitoring Key is mandatory in case of a fl owlevel monitoring since the rules are associated with the monitoring key and enabling/disabling of usage
monitoring at flow level can be controlled by PCRF using it. After the AVPs are parsed by DPCA, IMSA
updates the information to ECS. Once ECS is updated usage monitoring is started and constantly checked with
the usage threshold whenever the data traffic is present.
Usage monitoring is supported for static, predefined rules, and dynamic rule definitions.
 Usage Monitoring for Static Rules: In the case of static rules, the usage reporting on last rule removal
associated with the monitoring key is not applicable. In this case only the usage monitoring
information is received from the PCRF.
 Usage Monitoring for Predefined Rules: If the usage monitoring needs to be enabled for the predefined
rules, PCRF sends the rule and the usage monitoring information containing the monitoring key and
the usage threshold. The Monitoring key should be same as the one pre-configured in PCEF for that
predefined rule. There can be multiple rules associated with the same monitoring key. Hence enabling
a particular monitoring key would result in the data being tracked for multiple rules having the same
monitoring key. After DPCA parses the AVPs IMSA updates the information to ECS. Once ECS is
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updated usage monitoring is started and constantly checked with the usage threshold whenever the
data traffic is present.
 Usage Monitoring for Dynamic Rules: If the usage monitoring needs to be enabled for dynamic
ruledefs, PCRF provides the monitoring key along with a charging rule definition and the usage
monitoring information containing the monitoring key and the usage threshold. This would result in
the usage monitoring being done for all the rules associated with that monitoring key. After DPCA
parses the AVPs, IMSA updates the information to ECS. Once ECS is updated, the usage monitoring
is started and constantly checked with the usage threshold whenever the data traffic is present.
Monitoring key for dynamic ruledef is dynamically assigned by PCRF which is the only difference
with predefined rules in case of usage monitoring.
In releases prior to 15.0, when threshold breach happens for multiple monitoring keys at the same time, only one of the
monitoring key’s usage is reported and the rest of the monitoring keys’ usage is reported in CCR-T (threshold set to
infinity). On Tx expiry/TCP link error, unreported usage is stored at ECS and reported only on session termination.
In 15.0 and later releases, only one of the monitoring key’s usage is reported first. Upon receiving successful response
from PCRF, the rest of the monitoring keys’ usage is reported to PCRF. On Tx expiry/TCP link error, unreported usage
is stored at ECS. Any future successful interaction with PCRF for the session will send unreported UMI to PCRF.
Usage Reporting
Usage at subscriber/flow level is reported to PCRF under the following conditions:
 Usage Threshold Reached: PCEF records the subscriber data usage and checks if the usage threshold provided
by PCRF is reached. This is done for both session and rule level reporting.
For session-level reporting, the actual usage volume is compared with the usage volume threshold.
For rule-level reporting the rule that hits the data traffic is used to find out if the monitoring key is associated
with it, and based on the monitoring key the data usage is checked. Once the condition is met, it reports the
usage information to IMSA and continues monitoring. IMSA then triggers the CCR-U if “USAGE_REPORT”
trigger is enabled by the PCRF. The Usage-Monitoring-Information AVP is sent in this CCR with the “UsedService-Unit” set to the amount of data usage by subscriber.
If PCRF does not provide a new usage threshold in the usage monitoring information as a result of CCR from
PCEF when the usage threshold is reached, the usage monitoring is stopped at PCEF and no usage status is
reported.
In the non-standard Volume Reporting over Gx implementation, usage monitoring will be stopped once the
threshold is breached, else the monitoring will continue. There will be no further usage reporting until the CCA
is received.
 Usage Monitoring Disabled: If the PCRF explicitly disables the usage monitoring with Usage-MonitoringSupport AVP set to USAGE_MONITORING_DISABLED, the PCEF stops monitoring and reports t he usage
information (when the monitoring was enabled) to PCRF if the usage monitoring is disabled by PCRF as a
result of CCR from PCEF which is not related to reporting usage, other external triggers, or a PCRF internal
trigger. If the PCRF does not provide a new usage threshold as a result of CCR from PCEF when the usage
threshold is reached, the usage monitoring is stopped at PCEF and no further usage status is reported.
 IP CAN Session Termination: When the IP CAN session is terminated, the accumulated subscriber usage
information is reported to PCRF in the CCR-T from PCEF. If PCC usage level information is enabled by
PCRF, the PCC usage will also be reported.
 PCC Rule Removal: When the PCRF deactivates the last PCC rule associated with a usage monitoring key, the
PCEF sends a CCR with the data usage for that monitoring key. If the PCEF reports the last PCC rule
associated with a usage monitoring key is inactive, the PCEF reports the accumulated usage for that monitoring
key within the same CCR command if the Charging-Rule-Report AVP was included in a CCR command;
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otherwise, if the Charging-Rule-Report AVP was included in an RAA command, the PCEF sends a new CCR
command to report accumulated usage for the usage monitoring key. In 12.0 and later releases, usage reporting
on last rule deactivation using rule deactivation time set by PCRF is supported.
Releases prior to 14.0, when PCC rule was tried to be removed while waiting for access side update bearer
response, the charging rules were not removed. In 14.0 and later releases, on receiving message from PCRF,
the rule that is meant for removal is marked and then after the access side procedure is complete the rule is
removed.
 PCRF Requested Usage Report: In 10.2 and later releases, the accumulated usage since the last report is sent
even in case of immediate reporting, the usage is reset after immediate reporting and usage monitoring
continued so that the subsequent usage report will have the usage since the current report. In earlier releases the
behavior was to accumulate the so far usage in the next report.
 Release 12.2 onwards, usage reporting on bearer termination can be added. When a bearer is deleted due to some
reason, the rules associated with the bearer will also be removed. So, the usage will be reported on the
monitoring key(s) whose associated rule is the last one that is removed because of bearer termination.
 Revalidation Timeout: In the non-standard implementation, if usage monitoring and reporting is enabled and a
revalidation timeout occurs, the PCEF sends a CCR to request PCC rules and reports all accumulated usage for
all enabled monitoring keys since the last report (or since usage reporting was enabled if the usage was not yet
reported) with the accumulated usage at IP-CAN session level (if enabled) and at service data flow level (if
enabled) This is the default behavior.
In the case of standard implementation, this must be enabled by CLI configuration.
Important: The Usage Reporting on Revalidation Timeout feature is available by default in non-standard
implementation of Volume Reporting over Gx. In 10.2 and later releases, this is configurable in the standard
implementation. This is not supported in 10.0 release for standard based volume reporting.
Once the usage is reported, the usage counter is reset to zero. The PCEF continues to track data usage from the zero
value after the threshold is reached and before a new threshold is provided by the PCRF. If a new usage threshold is not
provided by the PCRF in the acknowledgement of an IP-CAN Session modification where its usage was reported, then
usage monitoring does not continue in the PCEF for that IP CAN session and and the usage accumulated between the
CCR-CCA will be discarded.
For information on how to configure the Volume Reporting over Gx feature, see the Configuring Volume Reporting
over Gx section.
ICSR Support for Volume Reporting over Gx (VoRoGx)
In releases prior to 15.0, post the ICSR switchover, any existing session for which the PCRF has enabled volume
reporting used to continue indefinitely until the session is terminated or until CCR-U is sent for a given trigger, without
having the volume counted via Gx.
To summarize, after an ICSR switchover, volume reporting over Gx is no longer done for existing sessions. Also,
volume usage is not synced to standby chassis.
In 15.0 and later releases, volume threshold and volume usage are synced to standby chassis to support volume
reporting over Gx for existing sessions post switchover.
Without this support it cannot cause a subscriber to use higher speeds than what s/he is supposed to get, if volume
reporting is for example used to enforce fair usage; the operator may already consider this a revenue loss. It will also
severely impact roaming subscribers who are supposed to get a notification and be blocked/redirected once the limits set
by the EU roaming regulation are reached. If a session continues now without being blocked, the operator is not allowed
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to charge for data beyond the limit and will have a significant and real revenue loss (roaming partner may still charge
for the data used on their SGSNs).
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Rel. 9 Gx Interface
Rel. 9 Gx interface support is available on the Cisco ASR chassis running StarOS 12.2 and later releases.
P-GW Rel. 9 Gx Interface Support
Introduction
The Gx reference point is located between the Policy and Charging Rules Function (PCRF) and the Policy and Charging
Enforcement Function (PCEF) on the Packet Data Network (PDN) Gateway (P-GW). The Gx reference point is used for
provisioning and removal of PCC rules from the PCRF to the PCEF and the transmission of traffic plane events from
the PCEF to the PCRF. The Gx reference point can be used for charging control, policy control, or both, by applying
AVPs relevant to the application.
The PCEF is the functional element that encompasses policy enforcement and flow based charging functionality. This
functional entity is located at the P-GW. The main functions include:
 Control over the user plane traffic handling at the gateway and its QoS.
 Service data flow detection and counting, as well as online and offline charging interactions.
 For a service data flow that is under policy control, the PCEF shall allow the service data flow to pass through
the gateway if and only if the corresponding gate is open.
 For a service data flow that is under charging control, the PCEF shall allow the service data flow to pass through
the gateway if and only if there is a corresponding active PCC rule and, for online charging, the OCS has
authorized the applicable credit with that charging key.
 If requested by the PCRF, the PCEF shall report to the PCRF when the status of the related service da ta flow
changes.
 In case the SDF is tunnelled at the BBERF, the PCEF shall inform the PCRF about the mobility protocol
tunnelling header of the service data flows at IP-CAN session establishment.
Terminology and Definitions
This section describes features and terminology pertaining to Rel. 9 Gx functionality.
Volume Reporting Over Gx
This section describes the 3GPP Rel. 9 Volume Reporting over Gx feature.
License Requirements
The Volume Reporting over Gx is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.
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Important: In 12.0 and later releases, no separate license is required for Charging over Gx / Volume Reporting
over Gx feature. This feature can be enabled as part of "Policy Interface" license.
Supported Standards
The Volume Reporting over Gx feature is based on the following standard:
3GPP TS 29.212 V9.5.0 (2010-06): 3rd Generation Partnership Project; Technical Specification Group Core Network
and Terminals; Policy and Charging Control over Gx reference point (Release 9).
Feature Overview
The Volume Reporting over Gx feature provides PCRF the capability to make real-time decisions based on the data
usage by subscribers.
Important: Volume Reporting over Gx is applicable only for volume quota.
Important: In release 10.0, only total data usage reporting is supported, uplink/downlink level reporting is not
supported. In 10.2 and later releases, it is supported.
Important: The PCEF only reports the accumulated usage since the last report for usage monitoring and not from
the beginning.
Important: If the usage threshold is set to zero (infinite threshold), no further threshold events will b e generated
by PCEF, but monitoring of usage will continue and be reported at the end of the session.
Important: In 12.2 and later releases, usage reporting on bearer termination is supported.
The following steps explain how Volume Reporting over Gx works:
1. PCEF after receiving the message from PCRF parses the usage monitoring related AVPs, and sends the
information to IMSA.
2. IMSA updates the information to ECS.
3. Once the ECS is updated with the usage monitoring information from PCRF, the PCEF (ECS) starts t racking the
data usage.
4. For session-level monitoring, the ECS maintains the amount of data usage.
5. For PCC rule monitoring, usage is monitored with the monitoring key as the unique identifier. Each node
maintains the usage information per monitoring key. When the data traffic is passed, the usage is checked
against the usage threshold values and reported as described in the Usage Reporting section.
6. The PCEF continues to track data usage after the threshold is reached and before a new threshold is provided by
the PCRF. If a new usage threshold is not provided by the PCRF in the acknowledgement of an IP-CAN
Session modification where its usage was reported, then usage monitoring does not continue in the PCEF for
that IP CAN session.
Usage Monitoring
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 Usage Monitoring at Session Level: PCRF subscribes to the session-level volume reporting over Gx by sending
the Usage-Monitoring-Information AVP with the usage threshold level set in Granted-Service-Unit AVP and
Usage-Monitoring-Level AVP set to SESSION_LEVEL(0). After the AVPs are parsed by DPCA, IMSA
updates the information to ECS. Once ECS is updated usage monitoring is started and constantly checked with
the usage threshold whenever the data traffic is present. In 11.0 and later releases, Monitoring Key at session
level is supported.
In 12.0 and later releases, enabling and disabling session usage in a single message from PCRF is supported.
This is supported only if the monitoring key is associated at session level.
In 12.0 and later releases, monitoring of usage based on input/output octet threshold levels is supported. Usage
is reported based on the enabled threshold level. If multiple levels are enabled, usage will be reported on all the
enabled levels even if only one of the levels is breached. Monitoring will be stopped on the missing threshold
levels in the response for the usage report from PCRF (expected to provide the complete set again if PCRF
wants to continue monitoring on the multiple levels enabled earlier).
Total threshold level along with UL/DL threshold level in the GSU AVP is treated as an error and only total
threshold level is accepted.
 Usage Monitoring at Flow Level: PCRF subscribes to the flow-level volume reporting over Gx by sending the
Usage-Monitoring-Information AVP with the usage threshold level set in Granted-Service-Unit AVP and
Usage-Monitoring-Level AVP set to PCC_RULE_LEVEL(1). Monitoring Key is mandatory in case of a flowlevel monitoring since the rules are associated with the monitoring key and enabling/disabling of usage
monitoring at flow level can be controlled by PCRF using it. After the AVPs are parsed by DPCA, IMSA
updates the information to ECS. Once ECS is updated usage monitoring is started and constantly checked with
the usage threshold whenever the data traffic is present.
Usage monitoring is supported for static, predefined rules, and dynamic rule definitions.
 Usage Monitoring for Static Rules: In the case of static rules, the usage reporting on last rule removal
associated with the monitoring key is not applicable. In this case only the usage monitoring
information is received from the PCRF.
 Usage Monitoring for Predefined Rules: If the usage monitoring needs to be enabled for the predefined
rules, PCRF sends the rule and the usage monitoring information containing the mo nitoring key and
the usage threshold. The Monitoring key should be same as the one pre-configured in PCEF for that
predefined rule. There can be multiple rules associated with the same monitoring key. Hence enabling
a particular monitoring key would result in the data being tracked for multiple rules having the same
monitoring key. After DPCA parses the AVPs IMSA updates the information to ECS. Once ECS is
updated usage monitoring is started and constantly checked with the usage threshold whenever the
data traffic is present.
 Usage Monitoring for Dynamic Rules: If the usage monitoring needs to be enabled for dynamic
ruledefs, PCRF provides the monitoring key along with a charging rule definition and the usage
monitoring information containing the monitoring key and the usage threshold. This would result in
the usage monitoring being done for all the rules associated with that monitoring key. After DPCA
parses the AVPs, IMSA updates the information to ECS. Once ECS is updated, the usage monitoring
is started and constantly checked with the usage threshold whenever the data traffic is present.
Monitoring key for dynamic ruledef is dynamically assigned by PCRF which is the only difference
with predefined rules in case of usage monitoring.
In releases prior to 15.0, when threshold breach happens for multiple monitoring keys at the same time, only one of the
monitoring key’s usage is reported and the rest of the monitoring keys’ usage is reported in CCR-T (threshold set to
infinity). On Tx expiry/TCP link error, unreported usage is stored at ECS and reported only on session termination.
In 15.0 and later releases, only one of the monitoring key’s usage is reported first. Upon receiving successful response
from PCRF, the rest of the monitoring keys’ usage is reported to PCRF. On Tx expiry/TCP link error, unreported usage
is stored at ECS. Any future successful interaction with PCRF for the session will send unreported UMI to PCRF.
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Usage Reporting
Usage at subscriber/flow level is reported to PCRF under the following conditions:
 Usage Threshold Reached: PCEF records the subscriber data usage and checks if the usage threshold provided
by PCRF is reached. This is done for both session and rule level reporting.
For session-level reporting, the actual usage volume is compared with the usage volume threshold.
For rule-level reporting the rule that hits the data traffic is used to find out if the monitoring key is associated
with it, and based on the monitoring key the data usage is checked. Once the condition is met, it reports the
usage information to IMSA and continues monitoring. IMSA then triggers the CCR-U if “USAGE_REPORT”
trigger is enabled by the PCRF. The Usage-Monitoring-Information AVP is sent in this CCR with the “UsedService-Unit” set to the amount of data usage by subscriber.
If PCRF does not provide a new usage threshold in the usage monitoring information as a result of CCR from
PCEF when the usage threshold is reached, the usage monitoring is stopped at PCEF and no usage status is
reported.
In the non-standard Volume Reporting over Gx implementation, usage monitoring will be stopped once the
threshold is breached, else the monitoring will continue. There will be no further usage reporting until the CCA
is received.
 Usage Monitoring Disabled: If the PCRF explicitly disables the usage monitoring with Usage-MonitoringSupport AVP set to USAGE_MONITORING_DISABLED, the PCEF stops monitoring and reports the usage
information (when the monitoring was enabled) to PCRF if the usage monitoring is disabled by PCRF as a
result of CCR from PCEF which is not related to reporting usage, other external triggers, or a PCRF internal
trigger. If the PCRF does not provide a new usage threshold as a result of CCR from PCEF when the usage
threshold is reached, the usage monitoring is stopped at PCEF and no further usage status is reported.
 IP CAN Session Termination: When the IP CAN session is terminated, the accumulated subscriber usage
information is reported to PCRF in the CCR-T from PCEF. If PCC usage level information is enabled by
PCRF, the PCC usage will also be reported.
 PCC Rule Removal: When the PCRF deactivates the last PCC rule associated with a usage monitoring key, the
PCEF sends a CCR with the data usage for that monitoring key. If the PCEF reports the last PCC rule
associated with a usage monitoring key is inactive, the PCEF reports the accumulated usage for that monitoring
key within the same CCR command if the Charging-Rule-Report AVP was included in a CCR command;
otherwise, if the Charging-Rule-Report AVP was included in an RAA command, the PCEF sends a new CCR
command to report accumulated usage for the usage monitoring key. In 12.0 and later releases, usage reporting
on last rule deactivation using rule deactivation time set by PCRF is supported.
Releases prior to 14.0, when PCC rule was tried to be removed while waiting for access side update bearer
response, the charging rules were not removed. In 14.0 and later releases, on receiving message from PCRF,
the rule that is meant for removal is marked and then after the access side procedure is complete the rule is
removed.
 PCRF Requested Usage Report: In 10.2 and later releases, the accumulated usage since the last report is sent
even in case of immediate reporting, the usage is reset after immediate reporting and usage monitoring
continued so that the subsequent usage report will have the usage since the current report. In earlier releases the
behavior was to accumulate the so far usage in the next report.
 Release 12.2 onwards, usage reporting on bearer termination can be added. When a bearer is deleted due to some
reason, the rules associated with the bearer will also be removed. So, the usage will be reported on the
monitoring key(s) whose associated rule is the last one that is removed because of bearer termination.
 Revalidation Timeout: In the non-standard implementation, if usage monitoring and reporting is enabled and a
revalidation timeout occurs, the PCEF sends a CCR to request PCC rules and reports all accumulated usage for
all enabled monitoring keys since the last report (or since usage reporting was enabled if the usage was not yet
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reported) with the accumulated usage at IP-CAN session level (if enabled) and at service data flow level (if
enabled) This is the default behavior.
In the case of standard implementation, this must be enabled by CLI configuration.
Important: The Usage Reporting on Revalidation Timeout feature is available by default in non-standard
implementation of Volume Reporting over Gx. In 10.2 and later releases, this is configurable in the standard
implementation. This is not supported in 10.0 release for standard based volume reporting.
Once the usage is reported, the usage counter is reset to zero. The PCEF continues to track data usage from the zero
value after the threshold is reached and before a new threshold is provided by the PCRF. If a new usage threshold is not
provided by the PCRF in the acknowledgement of an IP-CAN Session modification where its usage was reported, then
usage monitoring does not continue in the PCEF for that IP CAN session and and the usage accumulated between the
CCR-CCA will be discarded.
For information on how to configure the Volume Reporting over Gx feature, see the Configuring Volume Reporting
over Gx section.
ICSR Support for Volume Reporting over Gx (VoRoGx)
In releases prior to 15.0, post the ICSR switchover, any existing session for which the PCRF has enabled volume
reporting used to continue indefinitely until the session is terminated or until CCR-U is sent for a given trigger, without
having the volume counted via Gx.
To summarize, after an ICSR switchover, volume reporting over Gx is no longer done for existing sessions. Also,
volume usage is not synced to standby chassis.
In 15.0 and later releases, volume threshold and volume usage are synced to standby chassis to support volume
reporting over Gx for existing sessions post switchover.
Without this support it cannot cause a subscriber to use higher speeds than what s/he is supposed to get, if vo lume
reporting is for example used to enforce fair usage; the operator may already consider this a revenue loss. It will also
severely impact roaming subscribers who are supposed to get a notification and be blocked/redirected once the limits set
by the EU roaming regulation are reached. If a session continues now without being blocked, the operator is not allowed
to charge for data beyond the limit and will have a significant and real revenue loss (roaming partner may still charge
for the data used on their SGSNs).
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Assume Positive for Gx
In a scenario where both the primary and secondary PCRF servers are overloaded, the PCRF returns an error to P-GW
and HSGW. Current behavior for the P-GW and HSGW is to terminate the session if both primary and secondary return
a failure or timeout.
This feature is developed to enhance this behavior by applying local policy on the GW to ensure that the subscriber
session continues. P-GW / HSGW should implement Assume Positive feature to handle errors and based on the event
type implement specific rules.
Important: Use of Gx Assume Positive requires that a valid license key be installed. Contact your Cisco account
representative for information on how to obtain a license.
The failure handling behavior is enhanced to ensure that the subscriber service is maintained in case of PCRF
unavailability. It is also required that the GW reduces the traffic towards the PCRF when receiving a Diameter Too
Busy (3004) by stopping the transmission and reception of Diameter messages (CCRs and RARs) to and from the PCRF
for a configurable amount of time.
In case of any of the following failures with PCRF, the GW chooses to apply failure handling which results in
subscriber termination or to allow browsing without any more policy enforcement.
 TCP link failure
 Application Timer (Tx) expiry
 Result code based failures
In 14.1 and later releases, the PCRF is allowed to fall back to Local Policy for all connection level failures, result
code/experimental result code failures. Local Policy may choose to allow the subscriber for a configured amount of
time. During this time any subscriber/internal event on the call would be handled from Local Policy. After the expiry of
the timer, the subscriber session can be either terminated or else PCRF can be retried. Note that the retry attempt to
PCRF happens only when the timer-expiry event is configured as reconnect-to-server .
The fallback support is added to the failure handling template and the local policy service needs to be associated to IMS
Authorization service.
Once the local policy is applied, all PCRF enabled event triggers shall be disabled. Wh en the subscriber session is with
the local-policy, the GW skips sending of CCR-T and cleans up the session locally.
For a session that was created with active Gx session, the GW sends the CCR-T to primary and on failure sends the
CCR-T to the secondary PCRF. If the CCR-T returns a failure from both primary and secondary or times out, the GW
cleans up the session locally.
Fallback to Local Policy is done in the following scenarios:
 Tx timer expiry
 Diabase Error
 Result Code Error (Permanent/Transient)
 Experimental Result Code
 Response Timeout
The following points are applicable only in the scenario where reconnect to PCRF is attempted.
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 If the subscriber falls back to local-policy because of CCR-I failure, CCR-I will be sent to the PCRF after the
timer expiry. On successful CCA-I call will be continued with PCRF or else the call will be continued with
local-policy and retry-count will be incremented.
 If the subscriber falls back to local-policy because of the CCR-U failure, IMS Authorization application waits for
some event change to happen or to receive an RAR from PCRF.
 In case of event change after the timer expiry, CCR-U will be sent to PCRF. On successful CCA-U message, call
will be continued with PCRF or else call will be with local-policy and retry-count will be incremented.
 If RAR is received after the timer-expiry the call will be continued with the PCRF. On expiry of maximum of
retries to connect to PCRF, call will be disconnected.
Default Policy on CCR-I Failure
The following parameters are supported for local configuration on P-GW. The configuration parameters are
configurable per APN and per RAT Type.
The following fields for a Default Bearer Charging Rule are configurable per APN and per RAT Type:
 Rule Name
 Rating Group
 Service ID
 Online Charging
 Offline Charging
 QCI
 ARP
 Priority Level
 QCI
 QVI
 Max-Requested-Bandwidth
 UL
 DL
Flow Description and Flow Status are not configurable but the default value will be set to Any to Any and Flow Status
will be set to Enabled.
The following command level fields are configurable per APN and per RAT Type:
 AMBR
 UL
 DL
 QCI
 ARP
 Priority Level
 QCI
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 QVI
Gx Back off Functionality
This scenario is applicable when Primary PCRF cluster is unavailable but the secondary PCRF is available to handle
new CCR-I messages.
When the chassis receives 3004 result-code then back-off timer will be started for the peer and when the timer is
running no messages will be sent to that peer.
The timer will be started only when the value is being configured under endpoint configuration.
Releases prior to 15.0, when the IP CAN session falls back to local policy it remained with local policy until the
termination timer expires or the subscriber disconnects. Also, the RAR message received when the local-policy timer
was running got rejected with the cause "Unknown Session ID".
In 15.0 and later releases, P-GW/GGSN provides a fair chance for the subscriber to reconnect with PCRF in the event of
CCR failure. To support this feature, configurable validity and peer backoff timers are introduced in the Local Policy
Service and Diameter endpoint configuration commands. Also, the RAR received when the local-policy timer is running
will be rejected with the cause "DIAMETER_UNABLE_TO_DELIVER".
Configuring Gx Assume Positive Feature
To configure Gx Assume Positive functionality:
Step 1
At the global configuration level, configure Local Policy service for subscribers as described in the Configuring Local
Policy Service at Global Configuration Level section.
Step 2
At the global configuration level, configure the failure handling template to use the Local Policy service as described in
the Configuring Failure Handling Template at Global Configuration Level section.
Step 3
Within the IMS Authorization service, associate local policy service and failure handling template as described in the
Associating Local Policy Service and Failure Handling Template section.
Step 4
Verify your configuration as described in the Verifying Local Policy Service Configuration section.
Step 5
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Important: Commands used in the configuration examples in this section provide base functionality to
the extent that the most common or likely commands and/or keyword options are presented. In many cases,
other optional commands and/or keyword options are available. Refer to the Command Line Interface
Reference for complete information regarding all commands.
Configuring Local Policy Service at Global Configuration Level
Use the following example to configure Local Policy Service at global configuration level for subscribers:
configure
local-policy-service
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ruledef 2G_RULE
condition priority 1 apn match .*
exit
ruledef all-plmn
condition priority 1 serving-plmn match .*
exit
actiondef 2G_UPDATE
action priority 1 activate-ambr uplink 18000 downlink 18000
action priority 2 reject-requested-qos
exit
actiondef action1
action priority 2 allow-requested-qos
exit
actiondef allow
action priority 1 allow-session
exit
actiondef delete
action priority 1 terminate-session
exit
actiondef lp_fall
action priority 1 reconnect-to-server
exit
actiondef time
action priority 1 start-timer timer duration 10
exit
eventbase default
rule priority 1 event fallback ruledef 2G_RULE actiondef time continue
rule priority 2 event new-call ruledef 2G_RULE actiondef action1
rule priority 3 event location-change ruledef 2G_RULE actiondef action1
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rule priority 5 event timer-expiry ruledef 2G_RULE actiondef lp_fall
rule priority 6 event request-qos default-qos-change ruledef 2G_RULE
actiondef allow
end
Notes:
 On occurrence of some event, event will be first matched based on the priority under the eventbase default. For
the matched rule and if the corresponding ruledef satisfies, then specific action will be taken.
Configuring Failure Handling Template at Global Configuration Level
Use the following example to configure failure handling template at global configuration level:
configure
failure-handling-template <template_name>
msg-type any failure-type any action continue local-fallback
end
Notes:
 When the TCP link failure, Application Timer (Tx) expiry, or Result code based failure happens, the associated
failure-handling will be considered and if the failure-handling action is configured as local-fallback, then call
will fall back to local-fallback mode.
Associating Local Policy Service and Failure Handling Template
Use the following example to associate local policy service and failure handling template:
configure
context <context_name>
ims-auth-service <service_name>
associate local-policy-service <lp_service_name>
associate failure-handling <failure-handling-template-name>
end
Verifying Local Policy Service Configuration
To verify the local policy service configuration, use this command:
show local-policy statistics service <service_name>
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Time Reporting Over Gx
This section describes the Time Reporting over Gx feature supported for GGSN in this release.
License Requirements
No separate license is required for Time Reporting over Gx feature. This feature can be enabled as part of "Policy
Interface" license.
Contact your Cisco account representative for detailed information on specific licensing requirements. For information
on installing and verifying licenses, refer to the Managing License Keys section of the Software Management
Operations chapter in the System Administration Guide.
Feature Overview
This non-standard Time Usage Reporting over Gx feature is similar to Volume Usage Reporting over Gx. PCRF
provides the time usage threshold for entire session or particular monitoring key in CCA or RAR. When the given
threshold breached usage report will be sent to PCRF in CCR. This time threshold is independent of data traffic. Apart
from the usage threshold breach there are other scenarios where usage report will be send to PCRF.
Important: Time reporting over Gx is applicable only for time quota.
Important: The PCEF only reports the accumulated time usage since the last report for time monitoring and not
from the beginning.
Important: If the time usage threshold is set to zero (infinite threshold), no further threshold events will be
generated by PCEF, but monitoring of usage will continue and be reported at the end of the session.
Important: Time usage reporting on bearer termination is supported. When a bearer is deleted due to some
reason, the rules associated with the bearer will also be removed. So, the usage will be reported on the monitoring key(s)
whose associated rule is the last one that is removed because of bearer termination.
The following steps explain how Time Reporting over Gx works:
1. PCEF after receiving the message from PCRF parses the time monitoring related AVPs, and sends the
information to IMSA.
2. IMSA updates the information to ECS.
3. Once the ECS is updated with the time monitoring information from PCRF, the PCEF (ECS) starts tracking the
time usage.
4. For session-level monitoring, the ECS maintains the amount of time usage.
5. For PCC rule monitoring, usage is monitored with the monitoring key as the unique identifier. Each node
maintains the time usage information per monitoring key.
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6. The PCEF continues to track time usage after the threshold is reached and before a new threshold is provided by
the PCRF. If a new usage threshold is not provided by the PCRF in the acknowledgement of an IP-CAN
Session modification where its usage was reported, then time monitoring does not continue in the PCEF for
that IP CAN session.
Limitations
This section lists the limitations for Time Reporting over Gx in this release.
 Only integer monitoring key will be supported like Volume Reporting over Gx
 If the same monitoring key is used for both time and data volume monitoring then disabling monitoring key will
disable both time and data usage monitoring.
 If the same monitoring key is used for both time and data usage monitoring and if an immediate report request is
received, then both time and volume report of that monitoring key will be sent.
Usage Monitoring
Two levels of time usage reporting are supported:
 Usage Monitoring at Session Level
 Usage Monitoring at Flow Level
Usage Monitoring at Session Level
PCRF subscribes to the session level time reporting over Gx by sending the Usage-Monitoring-Information AVP with
the usage threshold level set in Granted-Service-Unit AVP and Usage-Monitoring-Level AVP set to SESSION_LEVEL
(0).
Usage Monitoring at Flow Level
PCRF subscribes to the flow level time reporting over Gx by sending the Usage-Monitoring-Information AVP with the
usage threshold level set in Granted-Service-Unit AVP and Usage-Monitoring-Level AVP set to
PCC_RULE_LEVEL(1). Monitoring Key is mandatory in case of a flow level monitoring since the rules are associated
with the monitoring key and enabling or disabling of usage monitoring at flow level can be controlled by PCRF using it.
Usage monitoring is supported for both predefined rules and dynamic rule definition.
Usage Monitoring for Predefined and Static Rules
If the usage monitoring needs to be enabled for the predefined rules, PCRF sends the rule and the usage monitoring
information containing the monitoring key and the usage threshold. The monitoring key should be same as the one pre configured in PCEF for that predefined rule. There can be multiple rules associated with the same monitoring key.
Hence enabling a particular monitoring key would result in the time being tracked for multiple rules having the same
monitoring key. Similarly, usage monitoring information is sent from PCRF for the static rules also.
Usage Monitoring for Dynamic Ruledefs
If the usage monitoring needs to be enabled for dynamic ruledefs, PCRF provides the monitoring key along with a
charging rule definition and the usage monitoring information containing th e monitoring key and the usage threshold.
This results in the usage monitoring being done for all the rules associated with that monitoring key.
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Usage Reporting
Time usage at subscriber/flow level is reported to PCRF under the following conditions:
 Usage Threshold Reached: PCEF records the subscriber usage and checks if the usage threshold provided by
PCRF is reached. Once the condition is met, it reports the usage information to IMSA and continues
monitoring. IMSA then triggers the CCR-U if "USAGE_REPORT" trigger is enabled by PCRF. The UsageMonitoring-Information AVP is sent in this CCR with the "CC-Time" in "Used-Service-Unit" set to track the
time usage of the subscriber.
 Usage Monitoring Disabled: If PCRF explicitly disables the usage monitoring with Usage-Monitoring-Support
AVP set to USAGE_MONITORING_DISABLED, PCEF stops monitoring and reports the usage information
(when the monitoring was enabled) to PCRF if the usage monitoring is disabled by PCRF as a result of CCR
from PCEF which is not related to reporting usage, other external triggers, or a PCRF internal trigger.
 IP CAN Session Termination: When the IP CAN session is terminated, the accumulated subscriber usage
information is reported to PCRF in the CCR-T from PCEF.
 PCC Rule Removal: When the PCRF deactivates the last PCC rule associated with a usage monitoring key,
PCEF sends a CCR with the usage time for that monitoring key. If the PCEF reports the last PCC rule
associated with a usage monitoring key is inactive, the PCEF reports the accumulated usage for that monitoring
key within the same CCR command if the Charging-Rule-Report AVP was included in a CCR command;
otherwise, if the Charging-Rule-Report AVP was included in an RAA command, the PCEF sends a new CCR
command to report accumulated usage for the usage monitoring key.
 PCRF Requested Usage Report: When PCRF provides the Usage-Monitoring-Information with the UsageMonitoring-Report set to USAGE_MONITORING_REPORT_REQUIRED, PCEF sends the time usage
information. If the monitoring key is provided by PCRF, time usage for that monitoring key is notified to
PCRF regardless of usage threshold. If the monitoring key is not provided by PCRF, time usage for all enabled
monitoring keys is notified to PCRF.
 Event Based Reporting: The event based reporting can be enabled through the CLI command event-update
send-usage-report events . When an event like sgsn change, qos change or revalidation-timeout is
configured under this CLI, time usage report is generated whenever that event happens.
Once the usage is reported, the usage counter is reset to zero. The PCEF continues to track time usage from the zero
value after the threshold is reached and before a new threshold is provided by the PCRF. If a new usage threshold is not
provided by the PCRF in the acknowledgement of an IP-CAN Session modification where its usage was reported, then
time usage monitoring does not continue in the PCEF for that IP CAN session.
For information on how to configure the Time Reporting over Gx feature, see the Configuring Time Reporting over Gx
section.
Configuring Time Reporting over Gx
This section describes the configuration required to enable Time Reporting over Gx.
To enable Time Reporting over Gx, use the following configuration:
configure
active-charging service <ecs_service_name>
rulebase <rulebase_name>
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action priority <priority> dynamic-only ruledef <ruledef_name> charging-action
<charging_action_name> monitoring-key <monitoring_key>
exit
exit
context <context_name>
ims-auth-service <imsa_service_name>
policy-control
event-update send-usage-report [ reset-usage ]
end
Notes:
 The configuration for enabling Time Reporting over Gx is same as the Volume Reporting over Gx configuration.
If a time threshold is received from PCRF then Time monitoring is done, and if a volume threshold is received
then Volume monitoring will be done.
 The maximum accepted monitoring key value by the PCEF is 4294967295. If the PCEF sends a greater value ,
the value is converted to an Unsigned Integer value.
 The event-update CLI enables time usage report to be sent in event updates. The optional keyword resetusage enables to support delta reporting wherein the usage is reported and reset at PCEF. If this option is not
configured, the behavior is to send the time usage information as part of event update but not reset at PCEF.
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Appendix E
Gy Interface Support
This chapter provides an overview of the Gy interface and describes how to configure the Gy interface.
Gy interface support is available on the Cisco system running StarOS 9.0 or later releases for the following products:
 GGSN
 HA
 IPSG
 PDSN
 P-GW
It is recommended that before using the procedures in this chapter you select the configuration example that best meets
your service model, and configure the required elements for that model as described in the administration guide for the
product that you are deploying.
This chapter describes the following topics:
 Introduction
 Features and Terminology
 Configuring Gy Interface Support
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Introduction
The Gy interface is the online charging interface between the PCEF/GW (Charging Trigger Function (CTF)) and the
Online Charging System (Charging-Data-Function (CDF)).
The Gy interface makes use of the Active Charging Service (ACS) / Enhanced Charging Service (ECS) for real -time
content-based charging of data services. It is based on the 3GPP standards and relies on quo ta allocation. The Online
Charging System (OCS) is the Diameter Credit Control server, which provides the online charging data to the
PCEF/GW. With Gy, customer traffic can be gated and billed in an online or prepaid style. Both time - and volumebased charging models are supported. In these models differentiated rates can be applied to different services based on
ECS shallow- or deep-packet inspection.
In the simplest possible installation, the system will exchange Gy Diameter messages over Diameter TCP links between
itself and one prepay server. For a more robust installation, multiple servers would be used. These servers may
optionally share or mirror a single quota database so as to support Gy session failover from one server to the other. For a
more scalable installation, a layer of proxies or other Diameter agents can be introduced to provide features such as
multi-path message routing or message and session redirection features.
The following figure shows the Gy reference point in the policy and charging architecture.
Figure 44.
PCC Logical Architecture
The following figure shows the Gy interface between CTF/Gateway/PCEF/Client running ECS and OCS (CDF/Server).
Within the PCEF/GW, the Gy protocol functionality is handled in the DCCA module (at the ECS).
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Figure 45.
Gy Architecture
License Requirements
The Gy interface support is a licensed Cisco feature. A separate feature license may be required. Contact your Cisco
account representative for detailed information on specific licensing requirements. For information on installing and
verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in the
System Administration Guide.
Supported Standards
Gy interface support is based on the following standards:
 IETF RFC 4006: Diameter Credit Control Application; August 2005
 3GPP TS 32.299 V9.6.0 (2010-12) 3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects; Telecommunication management; Charging management; Diameter charging applications
(Release 9)
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Features and Terminology
This section describes features and terminology pertaining to Gy functionality.
Charging Scenarios
Important: Online charging for events (“Immediate Event Charging” and “Event Charging with Reservation”) is
not supported. Only “Session Charging with Reservation” is supported.
Session Charging with Reservation
Session Charging with Unit Reservation is used for credit control of sessions.
Decentralized Unit Determination and Centralized Rating
In this scenario, the CTF requests the reservation of units prior to session supervision. An account debit operation is
carried out following the conclusion of session termination.
Centralized Unit Determination and Centralized Rating
In this scenario, the CTF requests the OCS to reserve units based on the session identifiers specified by the CTF. An
account debit operation is carried out following the conclusion of session.
Decentralized Unit Determination and Decentralized Rating
Important: Decentralized Rating is not supported in this release. Decentralized Unit determination is done using
CLI configuration.
In this scenario, the CTF requests the OCS to assure the reservation of an amount of the specified number of monetary
units from the subscriber's account. An account debit operation that triggers the deduction of the amount from the
subscriber's account is carried out following the conclusion of session establishment.
Basic Operations
Important: Immediate Event Charging is not supported in this release. “Reserve Units Request” and “Reserve
Units Response” are done for Session Charging and not for Event Charging.
Online credit control uses the basic logical operations “Debit Units” and “Reserve Units”.
 Debit Units Request; sent from CTF to OCS: After receiving a service request from the subscriber, the CTF
sends a Debit Units Request to the OCS. The CTF may either specify a service identifier (centralised unit
determination) or the number of units requested (decentralised unit determination). For refund purpose, the
CTF sends a Debit Units Request to the OCS as well.
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 Debit Units Response; sent from OCS to CTF: The OCS replies with a Debit Unit s Response, which informs the
CTF of the number of units granted as a result of the Debit Units Request. This includes the case where the
number of units granted indicates the permission to render the requested service. For refund purpose, the OCS
replies with a Debit Units Response.
 Reserve Units Request; sent from CTF to OCS: Request to reserve a number of units for the service to be
provided by an CTF. In case of centralised unit determination, the CTF specifies a service identifier in the
Reserve Unit Request, and the OCS determines the number of units requested. In case of decentralised unit
determination, the number of units requested is specified by the CTF.
 Reserve Units Response; sent from OCS to CTF: Response from the OCS which informs the CTF of t he number
of units that were reserved as a result of the “Reserve Units Request”.
Session Charging with Unit Reservation (SCUR) use both the “Debit Units” and “Reserve Units” operations. SCUR
uses the Session Based Credit Control procedure specified in RFC 4006. In session charging with unit reservation, when
the “Debit Units” and “Reserve Units” operations are both needed, they are combined in one message.
Important: Cost-Information, Remaining-Balance, and Low-Balance-Indication AVPs are not supported.
The consumed units are deducted from the subscriber's account after service delivery. Thus, the reserved and consumed
units are not necessarily the same. Using this operation, it is also possible for the CTF to modify the current reservation,
including the return of previously reserved units.
Re-authorization
The server may specify an idle timeout associated with a granted quota. Alternatively, the client may have a
configurable default value. The expiry of that timer triggers a re-authorization request.
Mid-session service events (re-authorisation triggers) may affect the rating of the current service usage. The server may
instruct the credit control client to re-authorize the quota upon a number of different session related triggers that can
affect the rating conditions.
When a re-authorization is trigger, the client reports quota usage. The reason for the quota being reported is notified to
the server.
Threshold based Re-authorization Triggers
The server may optionally include an indication to the client of the remaining quota threshold that triggers a quota reauthorization.
Termination Action
The server may specify to the client the behavior on consumption of the final granted units; this is known as termination
action.
Diameter Base Protocol
The Diameter Base Protocol maintains the underlying connection between the Diameter Client and the Diameter Server.
The connection between the client and server is TCP based. There are a series of message exchanges to check the status
of the connection and the capabilities.
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 Capabilities Exchange Messages: Capabilities Exchange Messages are exchanged between the diameter peers to
know the capabilities of each other and identity of each other.
 Capabilities Exchange Request (CER): This message is sent from the client to the server to know the
capabilities of the server.
 Capabilities Exchange Answer (CEA): This message is sent from the server to the client in response to
the CER message.
Important: Acct-Application-Id is not parsed and if sent will be ignored by the PCEF/GW. In
case the Result-Code is not DIAMETER_SUCCESS, the connection to the peer is closed.
 Device Watchdog Request (DWR): After the CER/CEA messages are exchanged, if there is no more traffic
between peers for a while, to monitor the health of the connection, DWR message is sent from the client. The
Device Watchdog timer (Tw) is configurable in PCEF/GW and can vary from 6 through 30 seconds. A very
low value will result in duplication of messages. The default value is 30 seconds. On two consecutive expiries
of Tw without a DWA, the peer is taken to be down.
Important: DWR is sent only after Tw expiry after the last message that came from the
server. Say if there is continuous exchange of messages between the peers, DWR might not be sent
if (Current Time - Last message received time from server) is less than Tw.
 Device Watchdog Answer (DWA): This is the response to the DWR message from the server. This is used to
monitor the connection state.
 Disconnect Peer Request (DPR): This message is sent to the peer to inform to shutdown the connection.
PCEF/GW only receives this message. There is no capability currently to send the message to the diameter
server.
 Disconnect Peer Answer (DPA): This message is the response to the DPR request from the peer. On receiving
the DPR, the peer sends DPA and puts the connection state to “DO NOT WANT TO TALK TO YOU” state
and there is no way to get the connection back except for reconfiguring the peer again.
A timeout value for retrying the disconnected peer must be provided.
 Tw Timer Expiry Behavior: The connection between the client and the server is taken care by the DIABASE
application. When two consecutive Tw timers are expired, the peer state is set to idle and the connection is
retried to be established. All the active sessions on the connection are then transferred to the secondary
connection if one is configured. All new session activations are also tried on the secondary connection.
There is a connection timeout interval, which is also equivalent to Tw timer, wherein after a CER has been sent
to the server, if there is no response received while trying to reestablish connection, the connection is closed
and the state set to idle.
Diameter Credit Control Application
The Diameter Credit Control Application (DCCA) is a part of the ECS subsystem. For every prepaid customer with
Diameter Credit Control enabled, whenever a session comes up, the Diameter server is contacted and quota for the
subscriber is fetched.
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Quota Behavior
Various forms of quotas are present that can be used to charge the subscriber in an efficient way. Various quota
mechanisms provide the end user with a variety of options to choose from and better handling of quotas for the service
provider.
Time Quotas
The Credit-Control server can send the CC-Time quota for the subscriber during any of the interrogation of client with
it. There are also various mechanisms as discussed below which can be used in conjunction with time quota to derive
variety of methods for customer satisfaction.
 Quota Consumption Time: The server can optionally indicate to the client that the quota consumption must be
stopped after a period equal to the “Quota Consumption Time” in which no packets are received or at session
termination, whichever is sooner. The idle period equal to the Quota Consumption Time is included in the
reported usage. The quota is consumed normally during gaps in traffic of duration less than or equal to the
Quota-Consumption-Time. Quota consumption resumes on receipt of a further packet belonging to the service
data flow.
If packets are allowed to flow during a CCR (Update)/CCA exchange, and the Quota-Consumption-Time AVP
value in the provided quota is the same as in the previously provided quota, then the Quota-Consumption-Time
runs normally through this procedure. For example, if 5 seconds of a 10 second QCT timer have passed when a
CCR(U) is triggered, and the CCA(U) returns 2 seconds later, then the QCT timer will expire 3 seconds after
the receipt of the CCA and the remaining unaccounted 5 seconds of usage will be recorded against the new
quota even though no packets were transmitted with the new quota.
A locally configurable default value in the client can be used if the server doesn't send the QCT in the CCA.
 Combinational Quota: Discrete-Time-Period (DTP) and Continuous-Time-Period (CTP) defines mechanisms
that extends and generalize the Quota-Consumption-Time for consuming time-quota.
 Both DTP and CTP uses a “base-time-interval” that is used to create time-envelopes of quota used.
 Instead of consuming the quota linearly, DTP and CTP consumes the granted quota discretely in chunks
of base-time-interval at the start of the each base-time-interval.
 Selection of one of this algorithm is based on the “Time-Quota-Mechanism” AVP sent by the server in
CCA.
 Reporting usage can also be controlled by Envelope-Reporting AVP sent by the server in CCA during
the quota grant. Based on the value of this AVP, the usage can be reported either as the usage per
envelope or as usual cumulative usage for that grant.
 Discrete-Time-Period: The base-time-interval defines the length of the Discrete-Time-Period. So each timeenvelope corresponds to exactly one Discrete-Time-Period. So when a traffic is detected, an envelope of size
equal to Base-Time-Interval is created. The traffic is allowed to pass through the time-envelope. Once the
traffic exceeds the base-time-interval another new envelope equal to the base-time-interval is created. This
continues till the quota used exceeds the quota grant or reaches the threshold limit for that quota.
 Continuous-Time-Period: Continuous time period mechanism constructs time envelope out of consecutive basetime intervals in which the traffic occurred up to and including a base time interval which contains no traffic.
Therefore the quota consumption continues within the time envelope, if there was traffic in the previous base
time interval. After an envelope has closed, then the quota consumption resumes only on the first traffic
following the closure of the envelope. The envelope for CTP includes the last base time interval which contains
no traffic.
The size of the envelope is not constant as it was in Parking meter. The end of the envelope can only be
determined retrospectively.
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 Quota Hold Time: The server can specify an idle timeout associated with a granted quota using the Quota Holding-Time AVP. If no traffic associated with the quota is observed for this time, the client understands that
the traffic has stopped and the quota is returned to the server. The client starts the quota holding timer when
quota consumption ceases. This is always when traffic ceases, i.e. the timer is re-started at the end of each
packet. It applies equally to the granted time quota and to the granted volume quota. The timer is stopped on
sending a CCR and re-initialized on receiving a CCA with the previous used value or a new value of QuotaHolding-Time if received.
Alternatively, if this AVP is not present, a locally configurable default value in the client is used. A QuotaHolding-Time value of zero indicates that this mechanism is not used.
 Quota Validity Time: The server can optionally send the validity time for the quota duri ng the interrogation with
the client. The Validity-Time AVP is present at the MSCC level and applies equally to the entire quota that is
present in that category. The quota gets invalidated at the end of the validity time and a CCR -Update is sent to
the server with the Used-Service-Units AVP and the reporting reason as VALIDITY_TIME. The entire quota
present in that category will be invalidated upon Quota-Validity-Time expiry and traffic in that category will
be passed or dropped depending on the configuration, till a CCA-Update is received with quota for that
category.
Validity-Time of zero is invalid. Validity-Time is relative and not absolute.
Volume Quota
The server sends the CC-Total-Octets AVP to provide volume quota to the subscriber. DCCA currently supports only
CC-Total-Octets AVP, which applies equally to uplink and downlink packets. If the total of uplink and downlink
packets exceeds the CC-Total-Octets granted, the quota is assumed to be exhausted.
If CC-Input-Octets and/or CC-Output-Octets is provided, the quota is counted against CC-Input-Octets and/or CCOutput-Octets respectively.
Important: Restricting usages based on CC-Input-Octets and CC_Output-Octets is not supported in this release.
Units Quota
The server can also send a CC-Service-Specific-Units quota which is used to have packets counted as units. The number
of units per packet is a configurable option.
Granting Quota
Gy implementation assumes that whenever the CC-Total-Octets AVP is present, volume quota has been granted for both
uplink and downlink.
If the Granted-Service-Unit contains no data, Gy treats it as an invalid CCA.
If the values are zero, it is assumed that no quota was granted.
If the AVP contains the sub AVPs without any data, it is assumed to be infinite quota.
Additional parameters relating to a category like QHT, QCT is set for the category after receiving a valid volume or
time grant.
If a default quota is configured for the subscriber, and subscriber traffic is received it is counted against the default
quota. The default quota is applicable only to the initial request and is not regranted during the course of the session. If
subscriber disconnects and reconnects, the default quota will be applied again for the initial request.
Requesting Quota
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Quotas for a particular category type can be requested using the Requested-Service-Unit AVP in the CCR. The MSCC
is filled with the Rating-Group AVP which corresponds to the category of the traffic and Requested-Service-Unit (RSU)
AVP without any data.
The Requested-Service-Unit can contain the CC AVPs used for requesting specific quantity of time or volume grant. Gy
CLI can be used to request quota for a category type.
Alternatively quota can also be requested from the server preemptively for a particular category in CCR - I. When the
server grants preemptive quota through the Credit control answer response, the quota will be used only when traffic is
hit for that category. Quota can be preemptively requested from the Credit Control server from the CLI.
In 12.3 and earlier releases, when no pre-emptive quota request is present in CCR-I, on hitting server unreachable state
for initial request, MSCC AVP with RSU is present in the CCR-I on server retries. Release 14.0 onwards, the MSCC
AVP is skipped in the CCR-I on server retries. Corresponding quota usage will be reported in the next CCR-U (MSCC
AVP with USU and RSU).
Reporting Quota
Quotas are reported to the server for number of reasons including:
 Threshold
 QHT Expiry
 Quota Exhaustion
 Rating Condition Change
 Forced Reauthorization
 Validity Time Expiry
 Final during Termination of Category Instance from Server
For the above cases except for QHT and Final, the Requested-Service-Unit AVP is present in the CCR.
Reporting Reason is present in CCR to let the server know the reason for the reporting of Quota. The Reporting-Reason
AVP can be present either in MSCC level or at Used Service Unit (USU) level depending on whether the reason applies
to all quotas or to single quota.
When one of these conditions is met, a CCR Update is sent to the server containing a Multiple-Services-Credit-Control
AVP(s) indicating the reason for reporting usage in the Reporting-Reason and the appropriate value(s) for Trigger,
where appropriate. Where a threshold was reached, the DCCA still has the amount of quota available to it defined by the
threshold.
For all other reporting reasons the client discards any remaining quota and either discards future user traffic matching
this category or allows user traffic to pass, or buffers traffic according to configuration.
For Reporting-Reason of Rating Condition Change, Gy requires the Trigger Type AVP to be present as part of the CCR
to indicate which trigger event caused the reporting and re-authorization request.
For Reporting-Reason of end user service denied, this happens when a category is blacklisted by the credit control
server, in this case a CCR-U is sent with used service unit even if the values as zero. When more quota is received from
the server for that particular category, the blacklisting is removed.
If a default quota has been set for the subscriber then the usage from the default quota is deducted from the initial GSU
received for the subscriber for the Rating Group or Rating Group and Service ID combination.
Default Quota Handling
 If default quota is set to 0, no data is passed/reported.
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 If default quota is configured and default quota is not exhausted before OCS responds with quota, trafic is
passed. Initial default quota used is counted against initial quota allocated. If quota allocated is less than the
actual usage then actual usage is reported and additional quota requested. If no additional quota is available
then traffic is denied.
 If default quota is not exhausted before OCS responds with denial of quota, gateway blocks traffic after OCS
response. Gateway will report usage on default quota even in this case in CCR-U (FINAL) or CCR-T.
 if default quota is consumed before OCS responds, if OCS is not declared dead (see definition in use case 1
above) then traffic is blocked until OCS responds.
Thresholds
The Gy client supports the following threshold types:
 Volume-Quota-Threshold
 Time-Quota-Threshold
 Units-Quota-Threshold
A threshold is always associated with a particular quota and a particular quota type. in the Multiple-Services-CreditControl AVP, the Time-Quota-Threshold, Volume-Quota-Threshold, and Unit-Quota-Threshold are optional AVPs.
They are expressed as unsigned numbers and the units are seconds for time quota, octets for volume quota and units for
service specific quota. Once the quota has reached its threshold, a request for more quotas is triggered toward the server.
User traffic is still allowed to flow. There is no disruption of traffic as the user still has valid quota.
The Gy sends a CCR Update with a Multiple-Services-Credit-Control AVP containing usage reported in one or more
User-Service-Unit AVPs, the Reporting-Reason set to THRESHOLD and the Requested-Service-Unit AVP without
data.
When quota of more than one type has been assigned to a category, each with its own threshold, then the th reshold is
considered to be reached once one of the unit types has reached its threshold even if the other unit type has not been
consumed.
When reporting volume quota, the DCCA always reports uplink and downlink separately using the CC-Input-Octets
AVP and the CC-Output-Octets AVP, respectively.
On receipt of more quotas in the CCA the Gy discard any quota not yet consumed since sending the CCR. Thus the
amount of quota now available for consumption is the new amount received less any quota that may have b een
consumed since last sending the CCR.
Conditions for Reauthorization of Quota
Quota is re-authorized/requested from the server in case of the following scenarios:
 Threshold is hit
 Quota is exhausted
 Validity time expiry
 Rating condition change:
 Cellid change: Applicable only to GGSN and P-GW implementations.
 LAC change: Applicable only to GGSN and P-GW implementations.
 QoS change
 RAT change
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 SGSN/Serving-Node change: Applicable only to GGSN and P-GW implementations.
Discarding or Allowing or Buffering Traffic to Flow
Whenever Gy is waiting for CCA from the server, there is a possibility of traffic for that particular traffic type to be
encountered in the Gy. The behavior of what needs to be done to the packet is determined by the configuration. Based
on the configuration, the traffic is either allowed to pass or discarded or buffered while waiting for CCA from the
server.
This behavior applies to all interrogation of client with server in the following cases:
 No quota present for that particular category
 Validity timer expiry for that category
 Quota exhausted for that category
 Forced Reauthorization from the server
In addition to allowing or discarding user traffic, there is an option available in case of quota exhausted or no quota
circumstances to buffer the traffic. This typically happens when the server has been requested for more quota, but a
valid quota response has not been received from the server, in this case the user traffic is buffered and on reception of
valid quota response from the server the buffered traffic is allowed to pass through.
Procedures for Consumption of Time Quota
 QCT is zero: When QCT is deactivated, the consumption is on a wall-clock basis. The consumption is
continuous even if there is no packet flow.
 QCT is active: When QCT is present in the CCA or locally configured for the session, then the consumption of
quota is started only at the time of first packet arrival. The quota is consumed normally till last packet arrival
plus QCT time and is passed till the next packet arrival.
If the QCT value is changed during intermediate interrogations, then the new QCT comes into effect from the
time the CCA is received. For instance, if the QCT is deactivated in the CCA, then quota consumptions resume
normally even without any packet flow. Or if the QCT is activated from deactivation, then the quota
consumption resume only after receiving the first packet after CCA.
 QHT is zero: When QHT is deactivated, the user holds the quota indefinitely in case there is no further usage
(for volume quota and with QCT for time quota). QHT is active between the CCA and the next CCR.
 QHT is non-zero: When QHT is present in CCA or locally configured for the session, then after a idle time of
QHT, the quota is returned to the server by sending a CCR-Update and reporting usage of the quota. On receipt
of CCR-U, the server does not grant quota. QHT timer is stopped on sending the CCR and is restarted only if
QHT is present in the CCA.
QHT timer is reset every time a packet arrives.
Envelope Reporting
The server may determine the need for additional detailed reports identifying start time and end times of specific
activity in addition to the standard quota management. The server controls this by sending a CCA with Envelope Reporting AVP with the appropriate values. The DCCA client, on receiving the command, will monitor for traffic for a
period of time controlled by the Quota-Consumption-Time AVP and report each period as a single envelope for each
Quota-Consumption-Time expiry where there was traffic. The server may request envelope reports for just time or time
and volume. Reporting the quota back to the server, is controlled by Envelope AVP with Envelope -Start-Time and
Envelope-End-Time along with usage information.
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Credit Control Request
Credit Control Request (CCR) is the message that is sent from the client to the server to request quota and authorization.
CCR is sent before the establishment of MIP session, and at the termination of the MIP session. It can be sent during
service delivery to request more quotas.
 Credit Control Request - Initial (CCR-I)
 Credit Control Request - Update (CCR-U)
 Credit Control Request - Terminate (CCR-T)
 Credit Control Answer (CCA)
 Credit Control Answer - Initial (CCA-I)
 Credit Control Answer - Update (CCA-U)
If the MSCC AVP is missing in CCA-Update it is treated as invalid CCA and the session is terminated.
 Credit Control Answer - Terminate (CCA-T)
The following figure depicts the call flow for a simple call request in the GGSN/P-GW/IPSG Gy implementation.
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Figure 46.
Gy Call Flow for Simple Call Request for GGSN/P-GW/IPSG
The following figure depicts the call flow for a simple call request in the HA Gy implementation.
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Figure 47.
Gy Call Flow for Simple Call Request for HA
Tx Timer Expiry Behavior
A timer is started each time a CCR is sent out from the system, and the response has to arrive within Tx time. The
timeout value is configurable in the Diameter Credit Control Configuration mode.
In case there is no response from the Diameter server for a particular CCR, within Tx time period, and if there is an
alternate server configured, the CCR is sent to the alternate server after Tw expiry as described in “Tw Timer expiry
behavior” section.
It also depends on the Credit-Control-Session-Failover AVP value for the earlier requests. If this AVP is present and is
coded to FAILOVER_SUPPORTED then the credit-control message stream is moved to the secondary server, in case it
is configured. If the AVP value is FAILOVER_NOT SUPPORTED, then the call is dropped in case of failures, even if a
secondary server is configured.
Redirection
In the Final-Unit-Indication AVP, if the Final-Action is REDIRECT or Redirect-Server AVP is present at command
level, redirection is performed.
The redirection takes place at the end of consumption of quota of the specified category. The GY sends a CCR-Update
without any RSU or Rating-Group AVP so that the server does not give any more quotas.
If the Final-Action AVP is RESTRICT_ACCESS, then according to the settings in Restriction -Filter-Rule AVP or
Filter-Id AVP. GY sends CCR-Update to the server with used quota.
Triggers
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The Diameter server can provide with the triggers for which the client should reauthorize a particular category. The
triggers can be configured locally as well but whatever trigger is present in the CCA from the server will have
precedence.
Important: In this release, Gy triggers are not supported for HA.
The trigger types that are supported are:
 SGSN/Serving-Node Change
 QoS Change - Any
 RAT Change
 LAC Change
 CellID Change
On any event as described in the Trigger type happens, the client reauthorizes quota with the server. The reporting
reason is set as RATING_CONDITION_CHANGE.
Tariff Time Change
The tariff change mechanism applies to each category instance active at the time of the tariff change whenever the
server indicated it should apply for this category.
The concept of dual coupon is supported. Here the server grants two quotas, which is accompanied by a Tariff-TimeChange, in this case the first granted service unit is used until the tariff change time, once the tariff change time is
reached the usage is reported up to the point and any additional usage is not accumulated, and then the second granted
service unit is used.
If the server expects a tariff change to occur within the validity time of the quota it is granting, then it includes the
Tariff-Time-Change AVP in the CCA. The DCCA report usage, which straddles the change time by sending two
instances of the Used-Service-Unit AVP, one with Tariff-Change-Usage set to UNIT_BEFORE_TARIFF_CHANGE,
and one with Tariff-Change-Usage set to UNIT_AFTER_TARIFF_CHANGE, and this independently of the type of
units used by application. Both Volume and Time quota are reported in this way.
The Tariff time change functionality can as well be done using Validity-Time AVP, where in the Validity-Time is set to
Tariff Time change and the client will reauthorize and get quota at Validity-Time expiry. This will trigger a lot of
reauthorize request to the server at a particular time and hence is not advised.
Tariff-Time-Usage AVP along with the Tariff-Time-Change AVP in the answer message to the client indicates that the
quotas defined in Multiple-Services-Credit-Control are to be used before or after the Tariff Time change. Two separate
quotas are allocated one for before Tariff-Time-Change and one for after Tariff-Time-Change. This gives the flexibility
to the operators to allocate different quotas to the users for different periods of time. In this case, the DCCA should not
send the Before-Usage and After-Usage counts in the update messages to the server. When Tariff-Time-Change AVP is
present without Tariff-Time-Usage AVP in the answer message, then the quota is used as in single quota mechanism
and the client has to send before usage and after usage quotas in the updates to the server.
Important: In this release, Gy does not support UNIT_INDETERMINATE value.
Final Unit Indication
The Final-Unit-Indication AVP can be present in the CCA from the server to indicate that the given quota is the final
quota from the server and the corresponding action as specified in the AVP needs to be taken.
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Final Unit Indication at Command Level
Gy currently does not support FUI AVP at command level. If this AVP is present at command level it is ignored. If the
FUI AVP is present at command level and the Final-Unit-Action AVP set to TERMINATE, Gy sends a CCR-Terminate
at the expiry of the quota, with all quotas in the USU AVP.
Important: FUI AVP at command level is only supported for Terminate action.
Final Unit Indication at MSCC Level
If the Final-Unit-Indication AVP is present at MSCC level, and if the Final-Unit-Action AVP is set to TERMINATE, a
CCR-Update is sent at the expiry of the allotted quota and report the usage of the category that is terminated.
For information on redirection cases refer to Redirection section.
Credit Control Failure Handling
CCFH AVP defines what needs to be done in case of failure of any type between the client and the server. The CCFH
functionality can be defined in configuration but if the CCFH AVP is present in the CCA, it takes precedence. CCFH
AVP gives flexibility to have different failure handling.
Gy supports the following Failure Handling options:
 TERMINATE
 CONTINUE
 RETRY AND TERMINATE
CCFH with Failover Supported
In case there is a secondary server is configured and if the CC-Session-Failover AVP is set to
FAILOVER_SUPPORTED, the following behavior takes place:
 Terminate: On any Tx expiry for the CCR-I the message is discarded and the session is torn down. In case of
CCR-Updates and Terminates the message is sent to the secondary server after response timeout and the
session is proceeded with the secondary server. In case there is a failure with the secondary server too, the
session is torn down.
 Continue: On any Tx expiry, the message is sent to the secondary server after response timeout and the session is
proceeded with the secondary server. In case there is a failure with the secondary server too, the session is still
established, but without quota management.
 Retry and Terminate: On any Tx expiry, the message is sent to the secondary server after the response timeout.
In case there is a failure with secondary server too, the session is taken down.
CCFH with Failover Not Supported
In case there is a secondary server configured and if the CC-Session-Failover AVP is set to
FAILOVER_NOT_SUPPORTED, the following behavior takes place as listed below. Same is the case if there is no
secondary server configured on the system.
 Terminate: On any Tx expiry, the session is taken down.
 Continue: On any Tx expiry, the session is still established, but without quota management.
 Retry and Terminate: On any Tx expiry, the session is taken down.
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Failover Support
The CC-Session-Failover AVP and the Credit-Control-Failure-Handling (CCFH) AVP may be returned by the CC
server in the CCA-I, and are used by the DCCA to manage the failover procedure. If they are present in the CCA they
override the default values that are locally configured in the system.
If the CC-Session-Failover is set to FAILOVER_NOT_SUPPORTED, a CC session will never be moved to an
alternative Diameter Server.
If the value of CC-Session-Failover is set to FAILOVER_SUPPORTED, then the Gy attempts to move the CC session
to the alternative server when it considers a request to have failed, i.e:
 On receipt of result code “DIAMETER_UNABLE_TO_DELIVER”, “DIAMETER_TOO_BUSY”, or
“DIAMETER_LOOP_DETECTED”.
 On expiry of the request timeout.
 On expiry of Tw without receipt of DWA, if the server is connected directly to the client.
The CCFH determines the behavior of the client in fault situations. If the Tx timer expires then based on the CCFH
value the following actions are taken:
 CONTINUE: Allow the MIP session and user traffic for the relevant category or categories to continue,
regardless of the interruption (delayed answer). Note that quota management of other categories is not affected.
 TERMINATE: Terminate the MIP session, which affects all categories.
 RETRY_AND_TERMINATE: Allow the MIP session and user traffic for the relevant category or categories to
continue, regardless of the interruption (delayed answer). The client retries to send the CCR when it determines
a failure-to-send condition and if this also fails, the MIP session is then terminated.
After the failover action has been attempted, and if there is still a failure to send or temporary error, depending on the
CCFH action, the following action is taken:
 CONTINUE: Allow the MIP session to continue.
 TERMINATE: Terminate the MIP session.
 RETRY_AND_TERMINATE: Terminate the MIP session.
Recovery Mechanisms
DCCA supports a recovery mechanism that is used to recover sessions without much loss of data in case of Session
Manager failures. There is a constant check pointing of Gy data at regular intervals and at important events like update,
etc.
For more information on recovery mechanisms, please refer to the System Administration Guide.
Error Mechanisms
Unsupported AVPs
All unsupported AVPs from the server with “M” bit set are ignored.
Invalid Answer from Server
If there is an invalid answer from the server, Gy action is dependent on the CCFH setting:
 In case of continue, the MIP session context is continued without further control from Gy.
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 In case of terminate and retry-and-terminate, the MIP session is terminated and a CCR-T is sent to the diameter
server.
Result Code Behavior
 DIAMETER_RATING_FAILED: On reception of this code, Gy discards all traffic for that category and does
not request any more quota from the server. This is supported at the MSCC level and not at the command level.
 DIAMETER_END_USER_SERVICE_DENIED: On reception of this code, Gy temporarily blacklists the
category and further traffic results in requesting new quota from the server. This is supported at the MSCC
level and not at the command level.
 DIAMETER_CREDIT_LIMIT_REACHED: On reception of this code, Gy discards all traffic for t hat category
and waits for a configured time, after which if there is traffic for the same category requests quota from the
server. This is supported at the MSCC level and not at the command level.
 DIAMETER_CREDIT_CONTROL_NOT_APPLICABLE: On reception of th is code, Gy allows the session to
establish, but without quota management. This is supported only at the command level and not at the MSCC
level.
 DIAMETER_USER_UNKNOWN: On reception of this code, DCCA does not allow the credit control session to
get established, the session is terminated. This result code is supported only at the command level and not at
the MSCC level.
For all other permanent/transient failures, Gy action is dependent on the CCFH setting.
Supported AVPs
The Gy functionality supports the following AVPs:
 Supported Diameter Credit Control AVPs specified in RFC 4006:
 CC-Input-Octets (AVP Code: 412):
Gy supports this AVP only in USU.
 CC-Output-Octets (AVP Code: 414):
Gy supports this AVP only in USU.
 CC-Request-Number (AVP Code: 415)
 CC-Request-Type (AVP Code: 416):
Gy currently does not support EVENT_REQUEST value.
 CC-Service-Specific-Units (AVP Code: 417)
 CC-Session-Failover (AVP Code: 418)
 CC-Time (AVP Code: 420):
Gy does not support this AVP in RSU.
 CC-Total-Octets (AVP Code: 421):
Gy does not support this AVP in RSU.
 Credit-Control-Failure-Handling (AVP Code: 427)
 Final-Unit-Action (AVP Code: 449):
Supported at Multiple-Services-Credit-Control grouped AVP level and not at command level.
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 Final-Unit-Indication (AVP Code: 430):
Fully supported at Multiple-Services-Credit-Control grouped AVP level and partially supported
(TERMINATE) at command level.
 Granted-Service-Unit (AVP Code: 431)
 Multiple-Services-Credit-Control (AVP Code: 456)
 Multiple-Services-Indicator (AVP Code: 455)
 Rating-Group (AVP Code: 432)
 Redirect-Address-Type (AVP Code: 433):
Gy currently supports only URL (2) value.
 Redirect-Server (AVP Code: 434)
 Redirect-Server-Address (AVP Code: 435)
 Requested-Service-Unit (AVP Code: 437)
 Result-Code (AVP Code: 268)
 Service-Context-Id (AVP Code: 461)
 Service-Identifier (AVP Code: 439)
 Subscription-Id (AVP Code: 443)
 Subscription-Id-Data (AVP Code: 444)
 Subscription-Id-Type (AVP Code: 450)
 Tariff-Change-Usage (AVP Code: 452):
Gy does NOT support UNIT_INDETERMINATE (2) value.
 Tariff-Time-Change (AVP Code: 451)
 Used-Service-Unit (AVP Code: 446):
Gy sends only incremental counts for all the AVPs from the last CCA-U.
 User-Equipment-Info (AVP Code: 458)
 User-Equipment-Info-Type (AVP Code: 459):
Gy currently supports only IMEISV value.
Cisco GGSN and P-GW support IMEISV by default.
 User-Equipment-Info-Value (AVP Code: 460)
 Validity-Time (AVP Code: 448)
 Supported 3GPP specific AVPs specified in 3GPP TS 32.299:
 3GPP-Charging-Characteristics (AVP Code: 13)
 3GPP-Charging-Id (AVP Code: 2)
 3GPP-GGSN-MCC-MNC (AVP Code: 9)
 3GPP-GPRS-QoS-Negotiated-Profile (AVP Code: 5)
 3GPP-IMSI-MCC-MNC (AVP Code: 8)
 3GPP-NSAPI (AVP Code: 10)
 3GPP-PDP-Type (AVP Code: 3)
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 3GPP-RAT-Type (AVP Code: 21)
 3GPP-Selection-Mode (AVP Code: 12)
 3GPP-Session-Stop-Indicator (AVP Code: 11)
 3GPP-SGSN-MCC-MNC (AVP Code: 18)
 3GPP-User-Location-Info (AVP Code: 22)
 Base-Time-Interval (AVP Code: 1265)
 Charging-Rule-Base-Name (AVP Code: 1004)
 Envelope (AVP Code: 1266)
 Envelope-End-Time (AVP Code: 1267)
 Envelope-Reporting (AVP Code: 1268)
 Envelope-Start-Time (AVP Code: 1269)
 GGSN-Address (AVP Code: 847)
 Offline-Charging (AVP Code: 1278)
 PDP-Address (AVP Code: 1227)
 PDP-Context-Type (AVP Code: 1247)
This AVP is present only in CCR-I.
 PS-Information (AVP Code: 874)
 Quota-Consumption-Time (AVP Code: 881):
This optional AVP is present only in CCA.
 Quota-Holding-Time (AVP Code: 871):
This optional AVP is present only in the CCA command. It is contained in the Multiple-ServicesCredit-Control AVP. It applies equally to the granted time quota and to the granted volume quota.
 Reporting-Reason (AVP Code: 872):
Gy currently does not support the POOL_EXHAUSTED (8) value. It is used in case of credit -pooling
which is currently not supported.
 Service-Information (AVP Code: 873):
Only PS-Information is supported.
 SGSN-Address (AVP Code: 1228)
 Time-Quota-Mechanism (AVP Code: 1270):
The Gy server may include this AVP in an Multiple-Services-Credit-Control AVP when granting time
quota.
 Time-Quota-Threshold (AVP Code: 868)
 Time-Quota-Type (AVP Code: 1271)
 Trigger (AVP Code: 1264)
 Trigger-Type (AVP Code: 870)
 Unit-Quota-Threshold (AVP Code: 1226)
 Volume-Quota-Threshold (AVP Code: 869)
 Supported Diameter AVPs specified in 3GPP TS 32.299 V8.1.0:
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 Auth-Application-Id (AVP Code: 258)
 Destination-Host (AVP Code: 293)
 Destination-Realm (AVP Code: 283)
 Disconnect-Cause (AVP Code: 273)
 Error-Message (AVP Code: 281)
 Event-Timestamp (AVP Code: 55)
 Failed-AVP (AVP Code: 279)
 Multiple-Services-Credit-Control (AVP Code: 456)
 Origin-Host (AVP Code: 264)
 Origin-Realm (AVP Code: 296)
 Origin-State-Id (AVP Code: 278)
 Redirect-Host (AVP Code: 292)
 Redirect-Host-Usage (AVP Code: 261)
 Redirect-Max-Cache-Time (AVP Code: 262)
 Rating-Group (AVP Code: 432)
 Result-Code (AVP Code: 268)
 Route-Record (AVP Code: 282)
 Session-Id (AVP Code: 263)
 Service-Context-Id (AVP Code: 461)
 Service-Identifier (AVP Code: 439)
 Supported-Vendor-Id (AVP Code: 265)
 Termination-Cause (AVP Code: 295)
 Used-Service-Unit (AVP Code: 446)
 User-Name (AVP Code: 1)
Unsupported AVPs
This section lists the AVPs that are NOT supported.
 NOT Supported Credit Control AVPs specified in RFC 4006:
 CC-Correlation-Id
 CC-Money
 CC-Sub-Session-Id
 CC-Unit-Type (AVP Code: 454)
 Check-Balance-Result
 Cost-Information (AVP Code: 423)
 Cost-Unit (AVP Code: 445)
 Credit-Control
 Currency-Code (AVP Code: 425)
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 Direct-Debiting-Failure-Handling (AVP Code: 428)
 Exponent (AVP Code: 429)
 G-S-U-Pool-Identifier (AVP Code: 453)
 G-S-U-Pool-Reference (AVP Code: 457)
 Requested-Action (AVP Code: 436)
 Service-Parameter-Info (AVP Code: 440)
 Service-Parameter-Type (AVP Code: 441)
 Service-Parameter-Value (AVP Code: 442)
 Unit-Value (AVP Code: 424)
 Value-Digits (AVP Code: 447)
 NOT supported Diameter AVPs specified in 3GPP TS 32.299 V8.1.0:
 Acct-Application-Id (AVP Code: 259)
 Error-Reporting-Host (AVP Code: 294)
 Experimental-Result (AVP Code: 297)
 Experimental-Result-Code (AVP Code: 298)
 Proxy-Host
 Proxy-Info
 Proxy-State
 NOT supported 3GPP-specific AVPs specified in 3GPP TS 32.299 V8.1.0:
 3GPP-CAMEL-Charging-Info (AVP Code: 24)
 3GPP-MS-TimeZone (AVP Code: 23)
 3GPP-PDSN-MCC-MNC
 Authorised-QoS
 Access-Network-Information
 Adaptations
 Additional-Content-Information
 Additional-Type-Information
 Address-Data
 Address-Domain
 Addressee-Type
 Address-Type
 AF-Correlation-Information
 Alternate-Charged-Party-Address
 Application-provided-Called-Party-Address
 Application-Server
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 Application-Server-Information
 Applic-ID
 Associated-URI
 Aux-Applic-Info
 Bearer-Service
 Called-Asserted-Identity
 Called-Party-Address
 Calling-Party-Address
 Cause-Code
 Charged-Party
 Class-Identifier
 Content-Class
 Content-Disposition
 Content-Length
 Content-Size
 Content-Type
 Data-Coding-Scheme
 Deferred-Location-Event-Type
 Delivery-Report-Requested
 Destination-Interface
 Domain-Name
 DRM-Content
 Early-Media-Description
 Event
 Event-Type
 Expires
 File-Repair-Supported
 IM-Information
 IMS-Charging-Identifier (ICID)
 IMS-Communication-Service-Identifier
 IMS-Information
 Incoming-Trunk-Group-ID
 Interface-Id
 Interface-Port
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 Interface-Text
 Interface-Type
 Inter-Operator-Identifier
 LCS-APN
 LCS-Client-Dialed-By-MS
 LCS-Client-External-ID
 LCS-Client-ID
 LCS-Client-Name
 LCS-Client-Type
 LCS-Data-Coding-Scheme
 LCS-Format-Indicator
 LCS-Information
 LCS-Name-String
 LCS-Requestor-ID
 LCS-Requestor-ID-String
 Location-Estimate
 Location-Estimate-Type
 Location-Type
 Low-Balance-Indication
 MBMS-Information
 MBMS-User-Service-Type
 Media-Initiator-Flag
 Media-Initiator-Party
 Message-Body
 Message-Class
 Message-ID
 Message-Size
 Message-Type
 MMBox-Storage-Requested
 MM-Content-Type
 MMS-Information
 Node-Functionality
 Number-Of-Participants
 Number-Of-Received-Talk-Bursts
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 Number-Of-Talk-Bursts
 Originating-IOI
 Originator
 Originator-Address
 Originator-Interface
 Originator-SCCP-Address
 Outgoing-Trunk-Group-ID
 Participant-Access-Priority
 Participants-Group
 Participants-Involved
 PDG-Address
 PDG-Charging-Id
 PoC-Change-Condition
 PoC-Change-Time
 PoC-Controlling-Address
 PoC-Group-Name
 PoC-Information
 PoC-Server-Role
 PoC-Session-Id
 PoC-Session-Initialtion-Type
 PoC-Session-Type
 PoC-User-Role
 PoC-User-Role-IDs
 PoC-User-Role-info-Units
 Positioning-Data
 Priority
 PS-Append-Free-Format-Data (AVP Code: 867):
The PCEF/GW ignores this AVP if no PS free format data is stored for the online charging session.
 PS-Free-Format-Data (AVP Code: 866)
 PS-Furnish-Charging-Information (AVP Code: 865)
 RAI (AVP Code: 909)
 Read-Reply-Report-Requested
 Received-Talk-Burst-Time
 Received-Talk-Burst-Volume
 Recipient-Address
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 Recipient-SCCP-Address
 Refund-Information
 Remaining-Balance
 Reply-Applic-ID
 Reply-Path-Requested
 Requested-Party-Address
 Role-of-node
 SDP-Answer-Timestamp
 SDP-Media-Component
 SDP-Media-Description
 SDP-Media-Name
 SDP-Offer-Timestamp
 SDP-Session-Description
 SDP-TimeStamp
 Served-Party-IP-Address
 Service-Generic-Information
 Service-ID
 Service-Specific-Data
 Service-Specific-Info
 Service-Specific-Type
 SIP-Method
 SIP-Request-Timestamp
 SIP-Response-Timestamp
 SM-Discharge-Time
 SM-Message-Type
 SM-Protocol-Id
 SMSC-Address
 SMS-Information
 SMS-Node
 SM-Status
 SM-User-Data-Header
 Submission-Time
 Talk-Burst-Exchange
 Talk-Burst-Time
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 Talk-Burst-Volume
 Terminating-IOI
 Time-Stamps
 Token-Text
 Trunk-Group-ID
 Type-Number
 User-Participating-Type
 User-Session-ID
 WAG-Address
 WAG-PLMN-Id
 WLAN-Information
 WLAN-Radio-Container
 WLAN-Session-Id
 WLAN-Technology
 WLAN-UE-Local-IPAddress
PLMN and Time Zone Reporting
For some implementations of online charging, the OCS requires the PCEF to reporting location-specific subscriber
information. For certain subscriber types, subscriber information such as PLMN, Time Zone, and ULI can be sent over
the Gy interface as the subscriber changes location, time zone, and serving networks to provide accurate online charging
services. Such information can be reported independently from time and volume-based reporting.
PLMN and Time Zone Reporting feature is enabled to support location event reporting based on triggers from Gx, when
the following conditions are met:
 Session-based Gy is not initiated due to the absence of charging-actions in rulebase with Credit-Control enabled
or due to delayed Gy session initiation.
 PLMN and Time Zone Reporting feature is either enabled in the credit control group or through the use of
triggers received from Gx.
If session-based Gy initiation fails or the session goes offline due to configuration or network issues, event -based Gy
session will not be initiated.
Important: Note that the failure-handling will not be supported for event-based Gy.
Though, in event-based Gy, multiple events can be reported independently and simultaneously this is presently not
supported. If an event occurs when the CCA-Event (CCA-E) of the previously reported event is awaited, then the new
event is queued and reported only when a CCA-E is received or the message is timed out.
To enable the PLMN and Time Zone Reporting feature, the PCRF shall send the Trigger AVP (Trigger Type 1, Trigger
Type 2) at the command level in a CCA.
The Event-based Gy session will be terminated in the following scenarios:
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 On termination of the bearer/subscriber (subscriber level Gy).
 Initiation of session-based Gy session (delayed session initiation).
 Once the CCR-E transaction is complete and there are no further events to report.
For information on how to configure this feature, refer to the Gy Interface Support chapter in the administration guide
for the product that uses the Gy interface functionality.
Interworking between Session-based Gy and Event-based Gy
If both session-based Gy and event-based Gy mode are activated, then session-based Gy will take precedence i.e. all the
events will be reported through CCR-U if the corresponding triggers are enabled. Event-based Gy mode will be active
only when session-based Gy has been disabled and has never been activated previously for this session during its
lifetime.
OCS Unreachable Failure Handling Feature
The OCS Unreachable Failure Handling feature is required to handle when OCS goes down or unavailable. This feature
is otherwise noted as Assume Positive for Gy.
The OCS is considered unavailable/unreachable in the following scenarios:
 PCEF transmits a CCR-U or CCR-I message but no response is received before the specified timeout
 Diameter Watchdog request times out to the current RDR, causing the TCP connection state to be marked down
 Diameter command-level error codes received in a CCA
 If the PCEF is unable to successfully verify transmission of a CCR-T, the PCEF will not assign interim quota,
because the user has disconnected.
In 15.0 and later releases, the error result codes can be configured using the CLI command servers-unreachable
behavior-triggers initial-request { result-code { any-error | result-code [ to endresult-code ] } } to trigger the server unreachable mode. The same is applicable for the update request also. For
more information on the CLI command, see the Credit Control Configuration Mode Commands chapter of the
Command Line Interface Reference. However, if the CLI command no servers-unreachable behaviortriggers { initial-request | update-request } result-code { any-error | result-code [ to
end-result-code ] } is configured, then the default set of hard-coded error codes are applicable.
The default set is:
 UNABLE_TO_DELIVER
3002
 UNABLE_TOO_BUSY
3004
 LOOP_DETECTED
3005
 ELECTION_LOST
4003
 Permanent failures
5001-5999 except 5002, 5003 and 5031.
In 12.2 and later releases, existing failure handling mechanism is enhanced such that the subscriber can be allowed to
browse for a pre-configured amount of interim-volume and/or interim-time if OCS becomes unreachable due to
transport connection failure or gives an impression that OCS is unreachable owing to slow response for Diameter
request messages.
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The purpose of this feature is to support Gy based data sessions in the event of an OCS outage. Diameter client allows
the user's data session to continue for some fixed quota and then retries the OCS server to restore normal functionality.
This feature adds more granularity to the existing failure handling mechanism.
With the implementation of this feature, Gy reporting during outages is supported. A temporary time and/or volume
quota is assigned to the user in the event of an OCS outage which will be used during the outage period.
When the OCS returns to service, the GW reports all used quota back to OCS and continues with n ormal Gy reporting.
For each DCCA-service, CLI control is available for the following options:
 Interim quota volume (in bytes) and quota time (seconds). Both values will apply simultaneously, if configured
together and if either quota time or quota volume is exhausted, the Diameter client retries the OCS.
 Option to limit the number of times a session can be assigned a temporary quota. If the user exceeds this amount,
the session will be terminated/converted to postpaid.
The quota value is part of the dcca-service configuration, and will apply to all subscribers using that dcca-service. The
temporary quota will be specified in volume (bytes) and/or time (seconds) to allow enforcement of both quota tracking
mechanisms individually or simultaneously.
When a user consumes the interim total quota or time configured for use during failure handling scenarios, the GW
retries the OCS server to determine if functionality has been restored. In the event that services have been restored,
quota assignment and tracking will proceed as per standard usage reporting procedures. Data used during the outage will
be reported to the OCS.
In the event that the OCS services have not been restored, the GW re-allocates the configured amount of quota and/or
time to the user. The GW reports all accumulated used data back to OCS when OCS is back online. If multiple retries
and interim allocations occur, the GW reports quota used during all allocation intervals. This cycle will continue until
OCS services have been successfully restored, or the maximum number of quota assignments has been exhausted.
Support for OCS unreachable CLI commands is added under Diameter Credit Control Configuration mode.
For the P-GW/XGW/GGSN, this behavior will apply to all APNs and subscribers that have onlin e charging enabled by
the PCRF. In the HA, this behavior will apply to all users that have online charging enabled by the AAA. Settings will
be applied to the dcca-service.
In Release 15.0, the following enhancements are implemented as part of the Assume Positive Gy feature:
 Configurable per error code treatment to enter assume positive mode
 Graceful session restart upon receipt of a 5002 error
Important: Note that the Graceful session restart feature is customer specific. For more information
contact your Cisco account representative.
Configurable per Error Code Treatment
This feature allows the customers to configure error result codes using the CLI command “ servers-unreachable
behavior-triggers ” that will trigger entering assume positive mode on the fly for CCR-Initial and CCR-Update
messages. CCR-Terminate message is currently not supported.
Any error result codes from the range 3xxx to 5xxx can be specified using the CLI commands. This feature has been
implemented to provide more flexibility and granularity in the way assume positive mode is triggered for error result
codes.
Graceful Session Restart
Graceful session restart upon receipt of a 5002 error code is supported for server retried CCR-U messages during
assume positive state. Also, any unreported usage from the time, server retried CCR-U sent till CCA-I is received, will
be reported immediately by triggering CCR-U with usages for the same.
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Important: Note that the Graceful session restart feature is customer specific. For more information
contact your Cisco account representative.
Any pending updates are aborted once CCA-U with 5002 is received from the server. Also CCR-U is triggered
immediately following session restart only if there are any unreported usages pending.
Important: When the server responds with 5002 error result code, it does not include any granted service units
for the requested rating groups.
For more information on the commands introduced in support of this feature, see the Credit Control Configuration
Mode Command chapter in the Command Line Interface Reference.
Backpressure
Diameter base (Diabase) maintains an outbound stream. When an application wants to write a message into a socket, the
message handle of those messages are stored in the outbound stream. Only on receiving the response to the
corresponding request, the stored message handle is removed from the outbound stream. In order to rate-limit the
message transactions based on the responses received from the server, ASR5k maintains a limit on the number of
messages stored in the outbound stream. This is done using "max-outstanding <>" CLI (default value is 256). If the
number of messages created by the application exceeds the max-outstanding limit, diabase sends a 'Backpressure'
indication to the application to wait till it receives a decongestion indication from diabase to try again.
On receiving a response from the server, the corresponding request message handle will be removed from the outbound
stream, creating a slot for another message to be written by the application. In order to intimate this slot availability,
decongestion notification is sent to the registered application. The application in turn loops through all sessions and
processes the pending trigger to be sent.
When the application loops through the sessions in the system, it traverse the sessions in a sorted order and checks each
session whether it has to send a pending CCR-Initial or CCR-Terminate or CCR-Update. When the first session gets the
slot to fill the outbound stream, it writes the message into the stream. Now the slot gets back into filled state, reaching
the max-outstanding limit again. So the rest of the sessions will still continue to be in backpressured state.
Backpressured request like Credit-Control-Initial and Credit-Control-Terminate are given higher priority over CreditControl-Update as they are concerned with the creation or termination of a session. So on top of the decongestion
notification, DCCA has some internal timers which periodically try to send the message out. So in case of heavy
backpressure condition, the probability of CCR-I or CCR-T being sent out is more than CCR-U.
Gy Backpressure Enhancement
This feature facilitates maintaining a list of DCCA sessions that hit backpressure while creating a message i.e.,
backpressured list, eliminating the current polling procedure. This will maintain a single queue for all types of messages
(CCR-I, CCR-U, CCR-T, CCR-E) that are backpressured. The messages will be sent in FIFO order from the queue.
After processing a session from the backpressure queue DCCA will check for the congestion status of the peer and
continue only if the peer has empty slots in the outstanding message queue to accommodate further CCRs.
Releases prior to 16.0, the gateway has a max-outstanding configuration to manage a number of messages that are
waiting for response from OCS. When the max-outstanding is configured to a low value, then the frequency to be in
congested state is very high.
CPU utilization is very high if the max-outstanding count is low and network is congested.
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In 16.0 and later releases, all DCCA sessions associated with the CCR messages that are triggered BACKPRESSURE
(when max-outstanding has been reached) will be queued in backpressure list which is maintained per ACS manager
instance (credit-control) level.
This list will not have any specific configurable limits on the number of sessions that will be queued in it. This is
because there is an inherent limit that is already present which is dependent on the number of subscriber/DCCA
sessions.
With this new separate backpressured list, CPU utilization will come down under high backpressure case.
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Configuring Gy Interface Support
To configure Gy interface support:
Step 1
Configure the core network service as described in this Administration Guide.
Step 2
Configure Gy interface support as described in the relevant section:
Configuring GGSN / P-GW / IPSG Gy Interface Support
Configuring HA / PDSN Gy Interface Support
Step 3
Configure Event-based Gy support as described in the Configuring PLMN and Time Zone Reporting section.
Step 4
Optional. Configure OCS Unreachable Failure Handling Feature or Assume Positive for Gy Feature as described in the
Configuring Server Unreachable Feature section.
Step 5
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Important: Commands used in the configuration examples in this section provide base functionality to
the extent that the most common or likely commands and/or keyword options are presented. In many cases,
other optional commands and/or keyword options are available. Refer to the Command Line Interface
Reference for complete information regarding all commands.
Configuring GGSN / P-GW / IPSG Gy Interface Support
To configure the standard Gy interface support for GGSN/P-GW/IPSG, use the following configuration:
configure
context <context_name>
diameter endpoint <endpoint_name>
origin realm <realm>
origin host <diameter_host> address <ip_address>
peer <peer> realm <realm> address <ip_address>
exit
exit
active-charging service <ecs_service_name>
credit-control [ group <cc_group_name> ]
diameter origin endpoint <endpoint_name>
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diameter peer-select peer <peer> realm <realm>
diameter pending-timeout <timeout_period>
diameter session failover
diameter dictionary <dictionary>
failure-handling initial-request continue
failure-handling update-request continue
failure-handling terminate-request continue
exit
exit
context <context_name>
apn <apn_name>
selection-mode sent-by-ms
ims-auth-service <service>
ip access-group <access_list_name> in
ip access-group <access_list_name> out
ip context-name <context_name>
active-charging rulebase <rulebase_name>
credit-control-group <cc_group_name>
end
Notes:
 For information on configuring IP access lists, refer to the Access Control Lists chapter in the System
Administration Guide.
 For more information on configuring ECS ruledefs, refer to the ACS Ruledef Configuration Mode Commands
chapter in the Command Line Interface Reference.
 For more information on configuring ECS charging actions, refer to the ACS Charging Action Configuration
Mode Commands chapter in the Command Line Interface Reference.
 For more information on configuring ECS rulebases, refer to the ACS Rulebase Configuration Mode Commands
chapter in the Command Line Interface Reference.
Configuring HA / PDSN Gy Interface Support
To configure HA / PDSN Gy interface support, use the following configuration:
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configure
context <context_name>
diameter endpoint <endpoint_name>
origin realm <realm>
origin host <diameter_host> address <ip_address>
peer <peer> realm <realm> address <ip_address>
exit
exit
active-charging service <ecs_service_name>
ruledef <ruledef_name>
ip any-match = TRUE
exit
charging-action <charging_action_name>
content-id <content_id>
cca charging credit rating-group <rating_group>
exit
rulebase <rulebase_name>
action priority <action_priority> ruledef <ruledef_name> charging-action
<charging_action_name>
exit
credit-control [ group <cc_group_name> ]
diameter origin endpoint <endpoint_name>
diameter peer-select peer <peer> realm <realm>
diameter pending-timeout <timeout>
diameter session failover
diameter dictionary <dictionary>
failure-handling initial-request continue
failure-handling update-request continue
failure-handling terminate-request continue
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pending-traffic-treatment noquota buffer
pending-traffic-treatment quota-exhausted buffer
exit
exit
context <context_name>
subscriber default
ip access-group <acl_name> in
ip access-group <acl_name> out
ip context-name <context_name>
active-charging rulebase <rulebase_name>
credit-control-group <cc_group_name>
end
Notes:
 For information on configuring IP access lists, refer to the Access Control Lists chapter in the Systems
Administration Guide.
 For more information on configuring ECS ruledefs, refer to the ACS Ruledef Configuration Mode Commands
chapter in the Command Line Interface Reference.
 For more information on configuring ECS charging actions, refer to the ACS Charging Action Configuration
Mode Commands chapter in the Command Line Interface Reference.
 For more information on configuring ECS rulebases, refer to the ACS Rulebase Configuration Mode Commands
chapter in the Command Line Interface Reference.
Configuring PLMN and Time Zone Reporting
PLMN and Time Zone Reporting feature requires a credit-control group to be defined in the APN or subscriber
configuration or there must be a default credit-control group configured. The following CLI commands are available to
enable/disable PLMN and Time Zone Reporting feature:
To enable PLMN and Time Zone Reporting through subscriber-template, use the following configuration:
configure
context <context_name>
subscriber name <subscriber_name>
dns primary <primary_ipaddress>
dns secondary <secondary_ipaddress>
ip access-group test in
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ip access-group test out
ip context-name <context_name>
credit-control-client event-based-charging
active-charging rulebase <rulebase_name>
exit
end
Notes:
 The credit-control-client event-based-charging command should be used to enable PLMN and
Time Zone Reporting.
For more information on configuring PLMN and Time Zone Reporting feature, refer to the Command Line
Interface Reference.
To enable PLMN and Time Zone Reporting through APN template, use the following configuration:
configure
context <context_name>
apn <apn_name>
selection-mode sent-by-ms
accounting-mode none
ip access-group test in
ip access-group test out
ip context-name <context_name>
ip address pool name<pool_name>
credit-control-client event-based-charging
active-charging rulebase <rulebase_name>
exit
end
Rest of the parameters needed for Event-based Gy such as dictionary, endpoint will be picked from the credit-control
group.
In a scenario where the triggers are configured through the CLI command and another set of triggers are also received
from Gx, then the triggers from Gx will have a higher priority.
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Configuring Server Unreachable Feature
The Server Unreachable feature requires a failure handling behavior to be defined in the Diameter Credit Control
configuration. The following CLI commands are available to enable/disable OCS Unreachable Failure Handling feature:
To enable OCS Unreachable Failure Handling feature, use the following configuration:
configure
require active-charging
active-charging service <service_name>
credit-control
servers-unreachable { initial-request | update-request } { continue |
terminate } [ { after-interim-volume <bytes> | after-interim-time <seconds> } +
server-retries <retry_count> ]
servers-unreachable behavior-triggers { initial-request | updaterequest } transport-failure [ response-timeout | tx-expiry ]
servers-unreachable behavior-triggers initial-request { result-code {
any-error | result-code [ to end-result-code ] } }
servers-unreachable behavior-triggers update-request { result-code {
any-error | result-code [ to end-result-code ] } }
end
Notes:
 This CLI command “ servers-unreachable { initial-request | update-request } { continue
| terminate } [ { after-interim-volume ... ” allows configuring interim-volume and interim-time
in the following ways:
 after-interim-volume <bytes> alone followed by server-retries.
 after-interim-time <secs> alone followed by server-retries.
 after-interim-volume <bytes> after-interim-time <secs> followed by server-retries.
 This CLI command “ servers-unreachable behavior-triggers” is used to trigger the serversunreachable failure handling at either Tx expiry or Response timeout (This CLI is similar to retry-after-txexpiry in “failure-handling update-request continue retry-after-tx-expiry ” command.).
 This CLI command “ servers-unreachable behavior-triggers initial-request { result-code
{ any-error | result-code [ to end-result-code ] } } ” is used to trigger the serversunreachable failure handling based on the configured Diameter error result codes.
For more information on configuring this feature, refer to the Command Line Interface Reference.
Gathering Statistics
This section explains how to gather Gy related statistics and configuration information.
In the following table, the first column lists what statistics to gather, and the second column lists the action to perform.
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Statistics/Information
Action to perform
Complete statistics for ECS sessions.
show active-charging sessions full
Detailed information for the Active
Charging Service (ACS)
show active-charging service all
Information on all rule definitions
configured in the service.
show active-charging ruledef all
Information on all charging actions
configured in the service.
show active-charging charging-action all
Information on all rulebases configured in
the service.
show active-charging rulebase all
Statistics of the Credit Control
application, DCCA.
show active-charging credit-control statistics
States of the Credit Control application's
sessions, DCCA.
show active-charging credit-control session-states [ rulebase
<rulebase_name> ] [ content-id <content_id> ]
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ICAP Interface Support
This chapter provides information on configuring the external Active Content Filtering servers for a core network
service subscriber. This chapter also describes the configuration and commands that are used to implement this feature.
It is recommended that you select the configuration example that best meets your service model, and configure the
required elements for that model, as described in respective product Administration Guide, before using the procedures
in this chapter.
The following products currently support ICAP interface functionality:
 GGSN
 P-GW
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ICAP Interface Support Overview
This feature supports streamlined ICAP interface to leverage Deep Packet Inspection (DPI) to enable external
application servers to provide their services without performing DPI, and without being inserted in the data flow. For
example with an external Active Content Filtering (ACF) Platform.
A high-level view of the streamlined ICAP interface support for external ACF is shown in the following figure:
Figure 48.
High-Level View of Streamlined ICAP Interface with external ACF
The system with ECS is configured to support DPI and the system uses this capability for content charging as well.
WAP and HTTP traffic is content filtered over the ICAP interface. RTSP traffic that contains adult content can also be
content filtered on the ICAP interface. Only the RTSP Request packets will be considered for content filtering over the
ICAP interface.
If a subscriber initiates a WAP (WAP1.x or WAP2.0) or Web session, the subsequent GET/POST request is detected by
the DPI function. The URL of the GET/POST request is extracted and passed, along with subscriber identification
information and the subscriber request, in an ICAP message to the application server. The application server checks the
URL on the basis of its category and other classifications like, type, access level, content category and decides if the
request should be authorized, blocked, or redirected by answering to the GET/POST with:
 A 200 OK message if the request is accepted.
 A 302 Redirect message in case of redirection. This redirect message includes the URL to which the subscriber
must be redirected.
 Deny-response code 200 for RTSP requests is not supported. Only 403 “Forbidden” deny -response code will be
supported.
Depending on the response received, the system with ECS will either pass the request unmodified, or discard the
message and respond to the subscriber with the appropriate redirection or block message.
Content charging is performed by the Active Charging Service (ACS) only after the request has been controlled by the
application server. This guarantees the appropriate interworking between the external application and content -based
billing. In particular, this guarantees that charging will be applied to the appropriate request in case of redirection, and
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that potential charging-based redirections (i.e. Advice of Charge, Top Up page, etc.) will not interfere with the decisions
taken by the application server.
Functions of the ACF include:
 Retrieval of subscriber policies based on the subscriber identity passed in the ICAP message
 Determining the appropriate action (permit, deny, redirect) to take for the type of content based on subscriber
profile
 Communication of the action (permit, deny, or redirect) decision for the URL back to the ACS module
Failure Action on Retransmitted Packets
ICAP rating is enabled for retransmitted packet when default ICAP failure action was taken on an ICAP request for that
flow. ICAP default failure action is taken on the pending ICAP request for a connection when the connection needs to
be reset and there is no other redundant connection available. For example, in the ICAP request timeout and ICAP
connection timeout scenarios. In these cases the retransmitted packet in the uplink direction is sent for ICAP rating
again.
In case of WAP CO, uplink retransmitted packet for the WAP transactions for which ICAP failure action was taken will
be sent for ICAP rating. WSP header of the retransmitted packet is not parsed by the WSP analyzer. The URL received
in the previous packet for that transaction is used for ICAP rating. If failure action was taken on multiple WTP
transactions for the same flow (case: WTP concatenated GET request) then uplink retransmitted packet for each of the
transaction is sent for rating again.
In case of HTTP, uplink retransmitted packets for the HTTP flow on which ICAP failure action is taken is sent for ICAP
rating. The URL present in the current secondary session (last uplink request) is used for ICAP rating. However, if there
were multiple outstanding ICAP request for the same flow (pipelined request) then for the retransmitted packet the URL
that will be sent for rating will be that of the last GET request.
Retransmission in various cases of failure-action taken on re-transmitted packets when the ICAP response is not
received for the original request and the retransmitted request comes in:
 WSP CO:
 Permit: The uplink packet is sent for ICAP rating and depending on the ICAP response the WTP
transaction is allowed/blocked. It is possible that the WAP gateway sends the response for the
permitted GET request. Hence, there is a race condition and the subscriber may be able to view the
web page even thought the rating was redirect or content insert.
 Content Insert: The retransmitted packet is not sent for ICAP rating.
 Redirect: The retransmitted packet is not sent for ICAP rating.
 Discard: The uplink packet is sent for ICAP rating and depending on the ICAP response the WTP
transaction is allowed/blocked.
 Terminate flow: The uplink packet is sent for ICAP rating and depending on the ICAP response t he
WTP transaction is allowed or blocked. The WAP gateway may send an Abort transaction for this
GET request if the WSP disconnect packet sent while terminating the flow is received by the WAP
gateway.
 HTTP:
 Permit: The uplink packet is sent for ICAP rating and depending on the ICAP response the last HTTP
GET request. It is possible that the HTTP server sends the response for the permitted GET request.
Hence there is a race condition and the subscriber may be able to view the web page even thought the
rating was redirect or content insert.
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 Content Insert: Retransmitted packets are dropped and not charged.
 Redirect: Retransmitted packets are dropped and not charged.
 Discard: The uplink packet is sent for ICAP rating and depending on the ICAP response the WTP
transaction allowed/blocked.
 Terminate flow: Retransmitted packets are dropped and not charged.
 RTSP:
The following scenarios describe the failure actions where an RTSP request is received from the client. If
ICAP is enabled, then the request goes to the ICAP server for content filtering.
 Allow: If the failure action configured is “allow”, the RTSP request packet is sent out after applying the
appropriate disposition action. Here, the flow remains the same as in the case if the ICAP response
received is 200 OK.
 Content Insert: If the failure action configured is “content-insertion <string of size 1 to 128>”, then this
failure action for RTSP request will not be supported. Instead the failure action “Discard” for such an
RTSP request will be supported.
 Redirect-URL: If the failure action configured is “redirect-url <string of size 1 to 128>”, then a TCP
FIN_ACK packet with an RTSP “302 Moved Temporarily” response header is inserted towards the
client containing the said URL for redirection. A TCP RST packet is inserted towards the server. The
underlying TCP connection is thus closed. If the RTSP client wants to retry to the redirected URL, the
opening of a new TCP connection must be initiated.
 Discard: If the failure action configured is “discard”, then the RTSP request packet received from the
client is quietly discarded and no notification is sent to the client.
 Terminate flow: If the failure action configured is “terminate-flow”, then the TCP connection is torn
down by injecting a TCP FIN-ACK towards the client and a RST packet towards the server. However,
no notification will be sent to the RTSP client and the server regarding this flow termination.
Supported Networks and Platforms
This feature supports ST16 and Cisco Chassis for the core network services configured on the system.
License Requirements
External Content Filtering Server support through Internet Content Adaptation Protocol (ICAP) interface is a licensed
Cisco feature. A separate feature license may be required. Contact your Cisco account representative for detailed
information on specific licensing requirements.
For information on installing and verifying licenses, refer to the Managing License Keys section of the Software
Management Operations chapter in the System Administration Guide.
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Configuring ICAP Interface Support
This section describes how to configure the Content Filtering Server Group (CFSG) through Internet Content
Adaptation Protocol (ICAP) interface between ICAP client and ACF server (ICAP server).
Important: This section provides the minimum instruction set for configuring external content filtering servers
on ICAP interface on the system. For more information on commands that configure additional parameters and options,
refer to CFSG Configuration Mode Commands chapter in Command Line Interface Reference.
To configure the system to provide ICAP interface support for external content filtering servers:
Step 1
Create the Content Filtering Server Group and create ICAP interface with origin (local) IP address of chassis by
applying the example configuration in the Creating ICAP Server Group and Address Binding section.
Step 2
Specify the active content filtering server (ICAP server) IP addresses and configure other parameters for ICAP server
group by applying the example configuration in the Configuring ICAP Server and Other Parameters section.
Step 3
Configure the content filtering mode to external content filtering server group mode in ECS rule base by applying the
example configuration in the Configuring ECS Rulebase for ICAP Server Group section.
Step 4
Optional. Configure the charging action to forward HTTP/RTSP/WAP GET request to external content filtering servers
on ICAP interface in Active Charging Configuration mode by applying the example configuration in the Configuring
Charging Action for ICAP Server Group section.
Step 5
Verify your ICAP interface and external content filtering server group configuration by following the steps in the
Verifying the ICAP Server Group Configuration section.
Step 6
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Creating ICAP Server Group and Address Binding
Use the following example to create the ICAP server group and bind the IP addresses:
configure
context <icap_ctxt_name> [ -noconfirm ]
content-filtering server-group <icap_svr_grp_name> [ -noconfirm ]
origin address <ip_address>
end
Notes:
 <ip_address> is local IP address of the CFSG endpoint.
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Configuring ICAP Server and Other Parameters
Use the following example to configure the active content filtering (ICAP server) and other related parameters:
configure
context <icap_context_name>
content-filtering server-group <icap_server_grp_name>
icap server <ip_address> [ port <port_number> ] [ max <max_msgs>] [ priority
<priority> ] [ standby ]
deny-message <msg_string>
response-timeout <timeout>
connection retry-timeout <retry_timeout>
failure-action { allow | content-insertion <content_string> | discard |
redirect-url <url> | terminate-flow }
dictionary { custom1 | custom2 | custom3 | standard }
end
Notes:
 In 8.1 and later releases, a maximum of five ICAP servers can be configured per Content Filtering Server Group.
In release 8.0, only one ICAP Server can be configured per Content Filtering Server Group.
 The standby keyword can be used to configure the ICAP server as standby. A maximum of ten active and
standby ICAP servers per Content Filtering Server Group can be configured. The active and standby servers
under the same server group can be configured to work in active-standby mode.
 The maximum outstanding request per ICAP connection configured using the optional max <max_msgs>
keyword is limited to one. Therefore, any other value configured using the max keyword will be ignored.
 Optional. To configure the ICAP URL extraction behavior, in the Content Filtering Server Group configuration
mode, enter the following command:
url-extraction { after-parsing | raw }
By default, percent-encoded hex characters in URLs sent from the ACF client to the ICAP server will be
converted to corresponding ASCII characters and sent.
Configuring ECS Rulebase for ICAP Server Group
Use the following example to configure the content filtering mode to ICAP server mode in the ECS rulebase for content
filtering:
configure
require active-charging [ optimized-mode ]
active-charging service <acs_svc_name> [ -noconfirm ]
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rulebase <rulebase_name> [ -noconfirm ]
content-filtering mode server-group <cf_server_group>
end
Notes:
 In release 8.1, the optimized-mode keyword enables ACS in the Optimized mode, wherein ACS functionality
is managed by SessMgrs. In release 8.1, ACS must be enabled in the Optimized mode.
 In release 8.3, the optimized-mode keyword is obsolete. With or without this keyword ACS is always enabled
in Optimized mode.
 In release 8.0 and release 9.0 and later, the optimized-mode keyword is not available.
Configuring Charging Action for ICAP Server Group
Use the following example to configure the charging action to forward HTTP/WAP GET request to ICAP server for
content processing:
configure
active-charging service <acs_svc_name>
charging-action <charging_action_name> [ -noconfirm ]
content-filtering processing server-group
end
Verifying the ICAP Server Group Configuration
This section explains how to display and review the configurations after saving them in a .cfg file and also to retrieve
errors and warnings within an active configuration for a service.
Important: All commands listed here are under Exec mode. Not all commands are available on all platforms.
These instructions are used to verify the configuration for this feature.
Step 1
Verify your ICAP Content Filtering Server Group configuration by entering the following command in Exec Mode:
show content-filtering server-group
The following is a sample output. In this example, an ICAP Content Filtering server group named
icap_cfsg1 was configured.
Content Filtering Group:
icap_cfsg1
Context:
icap1
Origin Address:
1.2.3.4
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ICAP Address(Port):
1.2.3.4(1344)
Max Outstanding:
256
Priority:
1
Response Timeout:
Timeout:
30(secs)
30(secs)
Connection Retry
Dictionary:
standard
Timeout Action:
terminate-flow
Deny Message:
"Service Not Subscribed"
URL-extraction:
after-parsing
Content Filtering Group Connections: NONE
Total content filtering groups matching specified criteria:
Step 2
Verify any configuration error in your configuration by entering the following command in Exec Mode:
show configuration errors
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Appendix G
L2TP Access Concentrator
This chapter describes the Layer 2 Tunneling Protocol (L2TP) Access Concentrator (LAC) functionality support on
Cisco® ASR 5x00 chassis and explains how it is configured.
The product Administration Guides provide examples and procedures for configuration of basic services on the system.
It is recommended that you select the configuration example that best meets your service model, and configure the
required elements for that model, as described in the respective product Administration Guide, before using the
procedures in this chapter.
Important: The L2TP Access Concentrator is a licensed Cisco feature. A separate feature license may be
required. Contact your Cisco account representative for detailed information on specific licensing requirements. For
information on installing and verifying licenses, refer to the Managing License Keys section of the Software
Management Operations chapter in the System Administration Guide.
When enabled though the session license and feature use key, the system supports L2TP for encapsulation of data
packets between it and one or more L2TP Network Server (LNS) nodes. In the system, this optional packet
encapsulation, or tunneling, is performed by configuring L2TP Access Concentrator (LAC) services within contexts.
Important: The LAC service uses UDP ports 13660 through 13668 as the source port for sending packets to the
LNS.
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▀ Applicable Products and Relevant Sections
Applicable Products and Relevant Sections
The LAC feature is supported for various products. The following table indicates the products on which the feature is
supported and the relevant sections within the chapter that pertain to that product.
Applicable Product(s)
PDSN/FA/HA
GGSN/SGSN/FA/PGW
ASN GW
Refer to Sections

Supported LAC Service Configurations for PDSN Simple IP

Supported LAC Service Configuration for Mobile IP

Configuring Subscriber Profiles for L2TP Support

RADIUS and Subscriber Profile Attributes Used

Configuring Local Subscriber Profiles for L2TP Support

Tunneling All Subscribers in a Specific Context Without Using RADIUS Attributes

Configuring LAC Services

Modifying PDSN Services for L2TP Support

Supported LAC Service Configurations for the GGSN

Supported LAC Service Configuration for Mobile IP

Configuring Subscriber Profiles for L2TP Support

RADIUS and Subscriber Profile Attributes Used

Configuring Local Subscriber Profiles for L2TP Support

Configuring LAC Services

Modifying APN Templates to Support L2TP

Supported LAC Service Configuration for Mobile IP

Configuring Subscriber Profiles for L2TP Support


RADIUS and Subscriber Profile Attributes Used

Configuring Local Subscriber Profiles for L2TP Support

Tunneling All Subscribers in a Specific Context Without Using RADIUS Attributes
Configuring LAC Services
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Supported LAC Service Configurations for PDSN Simple IP ▀
Supported LAC Service Configurations for PDSN Simple IP
LAC services can be applied to incoming PPP sessions using one of the following methods:
 Attribute-based tunneling: This method is used to encapsulate PPP packets for only specific users, identified
during authentication. In this method, the LAC service parameters and allowed LNS nodes that may be
communicated with are controlled by the user profile for the particular subscriber. The user profile can be
configured locally on the system or remotely on a RADIUS server.
 PDSN Service-based compulsory tunneling: This method of tunneling is used to encapsulate all incoming PPP
traffic from the R-P interface coming into a PDSN service, and tunnel it to an LNS peer for authentication. It
should be noted that this method does not consider subscriber configurations, since all auth entication is
performed by the peer LNS.
Each LAC service is bound to a single system interface configured within the same system context. It is recommended
that this context be a destination context as displayed in the following figure.
Figure 49.
LAC Service Configuration for SIP
Attribute-based Tunneling
This section describes the working of attribute-based tunneling and its configuration.
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How The Attribute-based L2TP Configuration Works
The following figure and the text that follows describe how Attribute-based tunneling is performed using the system.
Figure 50.
Attribute-based L2TP Session Processing for SIP
1. A subscriber session from the PCF is received by the PDSN service over the R-P interface.
2. The PDSN service attempts to authenticate the subscriber. The subscriber could be configured either locally or
remotely on a RADIUS server. Figure above shows subscriber authentication using a RADIUS AAA server.
3. The RADIUS server returns an Access-Accept message, which includes attributes indicating that session data is
to be tunneled using L2TP, and the name and location of the LAC service to use. An attribute could also be
provided indicating the LNS peer to connect to.
4. The PDSN service receives the information and then forwards the packets to the LAC service, configured within
the Destination context.
5. The LAC service, upon receiving the packets, encapsulates the information and forwards it to the appropriate
PDN interface for delivery to the LNS.
6. The encapsulated packets are sent to the peer LNS through the packet data network where they will be unencapsulated.
Configuring Attribute-based L2TP Support for PDSN Simple IP
This section provides a list of the steps required to configure attribute-based L2TP support for use with PDSN Simple IP
applications. Each step listed refers to a different section containing the specific instructions for completing the required
procedure.
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Important: These instructions assume that the system was previously configured to support subscriber data
sessions as a PDSN.
Step 1
Configure the subscriber profiles according to the information and instructions located in the Configuring Subscriber
Profiles for L2TP Support section of this chapter.
Step 2
Configure one or more LAC services according to the information and instructions located in the Configuring LAC
Services section of this chapter.
Step 3
Configure the PDSN service(s) with the tunnel context location according to the instructions located in the Modifying
PDSN Services for L2TP Support section of this chapter.
Step 4
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
PDSN Service-based Compulsory Tunneling
This section describes the working of service-based compulsory tunneling and its configuration.
How PDSN Service-based Compulsory Tunneling Works
PDSN Service-based compulsory tunneling enables wireless operators to send all PPP traffic to remote LNS peers over
an L2TP tunnel for authentication. This means that no PPP authentication is performed by the system.
Accounting start and interim accounting records are still sent to the local RADIUS server configured in the system’s
AAA Service configuration. When the L2TP session setup is complete, the system starts its call counters and signals the
RADIUS server to begin accounting. The subscriber name for accounting records is based on the NAI-constructed name
created for each session.
PDSN service-based compulsory tunneling requires the modification of one or more PDSN services and the
configuration of one or more LAC services.
The following figure and the text that follows describe how PDSN service-based compulsory tunneling is performed
using the system.
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Figure 51.
PDSN Service-based Compulsory Tunneling Session Processing
1.
A subscriber session from the PCF is received by the PDSN service over the R-P interface.
2.
The PDSN service detects its tunnel-type parameter is configured to L2TP and its tunnel-context parameter is
configured to the Destination context.
3.
The PDSN forwards all packets for the session to a LAC service configured in the Destination context. If multiple LAC
services are configured, session traffic will be routed to each using a round-robin algorithm.
4.
The LAC service initiates an L2TP tunnel to one of the LNS peers listed as part of its configuration.
5.
Session packets are passed to the LNS over a packet data network for authentication.
6.
The LNS authenticates the session and returns an Access-Accept to the PDSN.
7.
The PDSN service initiates accounting for the session using a constructed NAI.
Session data traffic is passed over the L2TP tunnel established in step 4.
Configuring L2TP Compulsory Tunneling Support for PDSN Simple IP
This section provides a list of the steps required to configure L2TP compulsory tunneling support for use with PDSN
Simple IP applications. Each step listed refers to a different section containing the specific instructions for completing
the required procedure.
Important: These instructions assume that the system was previously configured to support subscriber data
sessions as a PDSN.
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Supported LAC Service Configurations for PDSN Simple IP ▀
Step 1
Configure one or more LAC services according to the information and instructions located in the Configuring LAC
Services section of this chapter.
Step 2
Configure the PDSN service(s) according to the instructions located in the Modifying PDSN Services for L2TP Support
section of this chapter.
Step 3
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
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Supported LAC Service Configurations for the GGSN and P-GW
As mentioned previously, L2TP is supported through the configuration of LAC services on the system. Each LAC
service is bound to a single system interface configured within the same system destination context as displayed in
following figure.
Figure 52.
GGSN LAC Service Configuration
LAC services are applied to incoming subscriber PDP contexts based on the configuration of attributes either in the
GGSN/’s Access Point Name (APN) templates or in the subscriber’s profile. Subscriber profiles can be configured
locally on the system or remotely on a RADIUS server.
LAC service also supports domain-based L2TP tunneling with LNS. This method is used to create multiple tunnels
between LAC and LNS on the basis of values received in “Tunnel-Client-Auth-ID” or “Tunnel-Server-Auth-ID”
attribute received from AAA Server in Access-Accept as a key for tunnel selection and creation. When the LAC needs
to establish a new L2TP session, it first checks if there is any existing L2TP tunnel with the peer LNS based on the
value of key “Tunnel-Client-Auth-ID” or “Tunnel-Server-Auth-ID” attribute. If no such tunnel exists for the key, it will
create a new Tunnel with the LNS.
If LAC service needs to establish a new tunnel for new L2TP session with LNS and the tunnel create request fails
because maximum tunnel creation limit is reached, LAC will try other LNS addresses received from AAA server in
Access-Accept message. If all available peer-LNS are exhausted, LAC service will reject the call
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Supported LAC Service Configurations for the GGSN and P-GW ▀
L2TP tunnel parameters are configured within the APN template and are applied to all subscribers accessing the APN.
However, L2TP operation will differ depending on the subscriber’s PDP context type as described below:
 Transparent IP: The APN template’s L2TP parameter settings will be applied to the session.
 Non-transparent IP: Since authentication is required, L2TP parameter attributes in the subscriber profile (if
configured) will take precedence over the settings in the APN template.
 PPP: The APN template’s L2TP parameter settings will be applied and all of the subscriber’s PPP packets will
be forwarded to the specified LNS.
More detailed information is located in the sections that follow.
Transparent IP PDP Context Processing with L2TP Support
The following figure and the text that follows describe how transparent IP PDP contexts are processed when L2TP
tunneling is enabled.
Figure 53.
Transparent IP PDP Context Call Processing with L2TP Tunneling
1.
A Create PDP Context Request message for a subscriber session is sent from the SGSN to the GGSN service over the Gn
interface. The message contains information such as the PDP Type, APN, and charging characteristics.
2.
The GGSN determines whether or not it is configured with an APN identical to the one specified in the message. If so, it
determines how to process the session based on the configuration of the APN.
The APN configuration indicates such things as the IP address of the LNS, the system destination context in which a LAC
service is configured, and the outbound username and password that will be used by the LNS to authenticate incoming
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sessions. If no outbound information is configured, the subscriber’s International Mobile Subscriber Identity (IMSI) is
used as the username at the peer LNS.
1. The GGSN returns an affirmative Create PDP Context Response to the SGSN over the Gn interface.
2. The GGSN passes data received from the MS to a LAC service.
3. The LAC service encapsulates the IP packets and forwards it to the appropriate Gi interface for delivery to the
LNS.
4. The LNS un-encapsulates the packets and processes them as needed. The processing includes IP address
allocation.
Non-transparent IP PDP Context Processing with L2TP Support
The following figure and the text that follows describe how non-transparent IP PDP contexts are processed when L2TP
tunneling is enabled.
Figure 54.
Non-transparent IP PDP Context Call Processing with L2TP Tunneling
1. A Create PDP Context Request message for a subscriber session is sent from the SGSN to the GGSN service
over the Gn interface. The message contains information such as the PDP Type, APN, and charging
characteristics.
2. The GGSN determines whether or not it is configured with an APN identical to the one specified in the message.
If so, it determines how to process the session based on the configuration of the APN.
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The APN configuration indicates such things as the IP address of the LNS, the system destination context in
which a LAC service is configured, and the outbound username and password that will be used by the LNS to
authenticate incoming sessions. If no outbound information is configured, the subscriber’s username is sent to
the peer LNS.
3. The GGSN service authenticates the subscriber. The subscriber could be configured either locally or remotely on
a RADIUS server. Figure above shows subscriber authentication using a RADIUS AAA server.
As part of the authentication, the RADIUS server returns an Access-Accept message.
The message may include attributes indicating that session data is to be tunneled using L2TP, and the name and
location of the LAC service to use. An attribute could also be provided indicating the LNS peer to connect to.
If these attributes are supplied, they take precedence over those specified in the APN template.
4. The GGSN returns an affirmative Create PDP Context Response to the SGSN over the Gn interface.
5. The GGSN passes data received from the MS to a LAC service.
6. The LAC service encapsulates the IP packets and forwards it to the appropriate Gi interface for delivery to the
LNS.
7. The LNS un-encapsulates the packets and processes them as needed.The processing includes authentication and
IP address allocation.
PPP PDP Context Processing with L2TP Support
The following figure and the text that follows describe how non-transparent IP PDP contexts are processed when L2TP
tunneling is enabled.
Figure 55.
PPP PDP Context Call Processing with L2TP Tunneling
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1. A Create PDP Context Request message for a subscriber session is sent from the SGSN to the GGSN service
over the Gn interface. The message contains information such as the PDP Type, APN, and charging
characteristics.
2. The GGSN determines whether or not it is configured with an APN identical to the one specified in the message.
If so, it determines how to process the session based on the configuration of the APN.
The APN configuration indicates such things as the IP address of the LNS, the system destination context in
which a LAC service is configured.
Note that L2TP support could also be configured in the subscriber’s profile. If the APN is not configured for
L2TP tunneling, the system will attempt to authenticate the subscriber.The tunneling parameters in the
subscriber’s profile would then be used to determine the peer LNS.
3. The GGSN returns an affirmative Create PDP Context Response to the SGSN over the Gn interface.
4. The GGSN passes the PPP packets received from the MS to a LAC service.
5. The LAC service encapsulates the PPP packets and forwards it to the appropriate Gi interface for delivery to the
LNS.
6. The LNS un-encapsulates the packets and processes them as needed. The processing includes PPP termination,
authentication (using the username/password provided by the subscriber), and IP address allocation.
Configuring the GGSN or P-GW to Support L2TP
This section provides a list of the steps required to configure the GGSN or P-GW to support L2TP. Each step listed
refers to a different section containing the specific instructions for completing the required procedure.
Important: These instructions assume that the system was previously configured to support subscriber data
sessions as a GGSN or P-GW.
1. Configure the APN template to support L2TP tunneling according to the information and instructions located in
the Modifying APN Templates to Support L2TP section of this chapter.
Important: L2TP tunneling can be configured within individual subscriber profiles as
opposed/or in addition to configuring support with an APN template. Subscriber profile
configuration is described in the Configuring Subscriber Profiles for L2TP Support section of this
chapter.
2. Configure one or more LAC services according to the information and instructions located in the Configuring
LAC Services section of this chapter.
3. Save your configuration to flash memory, an external memory device, and/or a network location using the Exec
mode command save configuration . For additional information on how to verify and save configuration
files, refer to the System Administration Guide and the Command Line Interface Reference.
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Supported LAC Service Configuration for Mobile IP ▀
Supported LAC Service Configuration for Mobile IP
LAC services can be applied to incoming MIP sessions using attribute-based tunneling. Attribute-based tunneling is
used to encapsulate PPP packets for specific users, identified during authentication. In this method, the LAC service
parameters and allowed LNS nodes that may be communicated with are controlled by the user profile for the particular
subscriber. The user profile can be configured locally on the system or remotely on a RADIUS server.
Each LAC service is bound to a single system interface within the same system context. It is recommended that this
context be a destination context as displayed in figure below.
Figure 56.
LAC Service Configuration for MIP
How The Attribute-based L2TP Configuration for MIP Works
The following figure and the text that follows describe how Attribute-based tunneling for MIP is performed using the
system.
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Figure 57.
Attribute-based L2TP Session Processing for MIP
1. A subscriber session from the FA is received by the HA service over the Pi interface.
2. The HA service attempts to authenticate the subscriber. The subscriber could be configured either locally or
remotely on a RADIUS server. Figure above shows subscriber authentication using a RADIUS AAA server.
3. The RADIUS server returns an Access-Accept message, which includes attributes indicating that session data is
to be tunneled using L2TP, and the name and location of the LAC service to use. An attribute could also be
provided indicating the LNS peer to connect to.
4. The HA service receives the information and then forwards the packets to the LAC service, configured within
the Destination context.
5. The LAC service, upon receiving the packets, encapsulates the information and forwards it to the appropriate
PDN interface for delivery to the LNS.
6. The encapsulated packets are sent to the peer LNS through the packet data network where they will be un encapsulated.
Configuring Attribute-based L2TP Support for HA Mobile IP
This section provides a list of the steps required to configure attribute-based L2TP support for use with HA Mobile IP
applications. Each step listed refers to a different section containing the specific instructions for completing the required
procedure.
Important: These instructions assume that the system was previously configured to support subscriber data
sessions as an HA.
Step 1
Configure the subscriber profiles according to the information and instructions located in the Configuring Subscriber
Profiles for L2TP Support section of this chapter.
Step 2
Configure one or more LAC services according to the information and instructions located in the Configuring LAC
Services section of this chapter.
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Step 3
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
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Configuring Subscriber Profiles for L2TP Support
This section provides information and instructions on the following procedures:
 RADIUS and Subscriber Profile Attributes Used
 Configuring Local Subscriber Profiles for L2TP Support
 Configuring Local Subscriber
 Verifying the L2TP Configuration
Important: Since the instructions for configuring subscribers differ between RADIUS server applications, this
section only provides the individual attributes that can be added to the subscriber profile. Refer to the documentation
that shipped with your RADIUS server for instructions on configuring subscribers.
RADIUS and Subscriber Profile Attributes Used
Attribute-based L2TP tunneling is supported through the use of attributes configured in subscriber profiles stored either
locally on the system or remotely on a RADIUS server. The following table describes the attributes used in support of
LAC services. These attributes are contained in the standard and VSA dictionaries.
Table 27. Subscriber Attributes for L2TP Support
RADIUS
Attribute
Local
Subscriber
Attribute
Description
Variable
TunnelType
tunnel l2tp
Specifies the type of tunnel to be used for the
subscriber session
L2TP
TunnelServerEndpoint
tunnel l2tp
peer-address
Specifies the IP address of the peer LNS to
connect tunnel to.
IPv4 address in dotted-decimal format,
enclosed in quotation marks
TunnelPassword
tunnel l2tp
secret
Specifies the shared secret between the LAC and
LNS.
Alpha and or numeric string from 1 to 63
characters, enclosed in quotation marks
TunnelPrivateGroup-ID
tunnel l2tp
tunnelcontext
Specifies the name of the destination context
configured on the system in which the LAC
service(s) to be used are located.
Alpha and or numeric string from 1 to 63
characters, enclosed in quotation marks
Important: If the LAC service
and egress interface are configured in
the same context as the core service or
HA service, this attribute is not needed.
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RADIUS
Attribute
Local
Subscriber
Attribute
Description
Variable
TunnelPreference
tunnel l2tp
preference
Configures the priority of each peer LNS when
multiple LNS nodes are configured.
Integer from 1 to 65535
Important: This attribute is
only used when the loadbalancetunnel-peers parameter or SN-TunnelLoad-Balancing attribute configured
to prioritized.
SN-TunnelLoadBalancing
ClientEndpoint
loadbalancetunnel- peer
local-address
A vendor-specific attribute (VSA) used to
provides a selection algorithm defining how an
LNS node is selected by the RADIUS server
when multiple LNS peers are configured within
the subscriber profile.
Specifies the IP address of a specific LAC service
configured on the system that to use to facilitate
the subscriber’s L2TP session.
This attribute is used when multiple LAC services
are configured.

Random - Random LNS selection
order, the Tunnel-Preference
attribute is not used in determining
which LNS to select.

Balanced - LNS selection is
sequential balancing the load across
all configured LNS nodes, the
Tunnel-Preference attribute is not
used in determining which LNS to
select.

Prioritized - LNS selection is
made based on the priority assigned
in the Tunnel-Preference attribute.
IPv4 address in dotted decimal notation.
(xxx.xxx.xxx.xxx)
RADIUS Tagging Support
The system supports RADIUS attribute tagging for tunnel attributes. These “tags” organize together multiple attributes
into different groups when multiple LNS nodes are defined in the user profile. Tagging is useful to ensure that the
system groups all the attributes used for a specific server. If attribute tagging is not supported by your specific RADIUS
server, the system implicitly organizes the attributes in the order that they are listed in the access accept packet.
Configuring Local Subscriber Profiles for L2TP Support
This section provides information and instructions for configuring local subscriber profiles on the system to support
L2TP.
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Important: The configuration of RADIUS-based subscriber profiles is not discussed in this document. Please
refer to the documentation supplied with your RADIUS server for further information.
Important: This section provides the minimum instruction set for configuring local subscriber profile for L2TP
support on the system. For more information on commands that configure additional parameters and options, refer to the
LAC Service Configuration Mode Commands chapter in the Command Line Interface Reference.
To configure the system to provide L2TP support to subscribers:
Step 1
Configure the “Local” subscriber with L2TP tunnel parameters and the load balancing parameters with action by
applying the example configuration in the Configuring Local Subscriber section.
Step 2
Verify your L2TP configuration by following the steps in the Verifying the L2TP Configuration section.
Step 3
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Configuring Local Subscriber
Use the following example to configure the Local subscriber with L2TP tunnel parameters. Optionally you can
configure load balancing between multiple LNS servers:
configure
context <ctxt_name> [-noconfirm]
subscriber name <subs_name>
tunnel l2tp peer-address <lns_ip_address> [ preference <integer> | [ encrypted ]
secret <secret_string> | tunnel-context <context_name> | local-address <local_ip_address>
}
load-balancing { random | balanced | prioritized }
end
Notes:
 <ctxt_name > is the system context in which you wish to configure the subscriber profile.
 <lns_ip_address > is the IP address of LNS server node and <local_ip_address > is the IP address of
system which is bound to LAC service.
Verifying the L2TP Configuration
These instructions are used to verify the L2TP configuration.
Step 1
Verify that your L2TP configurations were configured properly by entering the following command in Exec Mode in
specific context:
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show subscriber configuration username user_name
The output of this command is a concise listing of subscriber parameter settings as configured.
Tunneling All Subscribers in a Specific Context Without Using RADIUS Attrib utes
As with other services supported by the system, values for subscriber profile attributes not returned as part of a
RADIUS Access-Accept message can be obtained using the locally configured profile for the subscriber named default.
The subscriber profile for default must be configured in the AAA context (i.e. the context in which AAA functionality is
configured).
As a time saving feature, L2TP support can be configured for the subscriber named default with no additional
configuration for RADIUS-based subscribers. This is especially useful when you have separate source/AAA contexts
for specific subscribers.
To configure the profile for the subscriber named default, follow the instructions above for configuring a local
subscriber and enter the name default.
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Configuring LAC Services
Important: Not all commands, keywords and functions may be available. Functionality is dependent on platform
and license(s).
This section provides information and instructions for configuring LAC services on the system allowing it to
communicate with peer LNS nodes.
Important: This section provides the minimum instruction set for configuring LAC service support on the
system. For more information on commands that configure additional parameters and options, refer to the LAC Service
Configuration Mode Commands chapter in the Command Line Interface Reference.
To configure the LAC services on system:
Step 1
Configure the LAC service on system and bind it to an IP address by applying the example configuration in the
Configuring LAC Service section.
Step 2
Optional. Configure LNS peer information if the Tunnel-Service-Endpoint attribute is not configured in the subscriber
profile or PDSN compulsory tunneling is supported by applying the example configuration in the Configuring LNS Peer
section.
Step 3
Verify your LAC configuration by following the steps in the Verifying the LAC Service Configuration section.
Step 4
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Configuring LAC Service
Use the following example to create the LAC service and bind the service to an IP address:
configure
context <dst_ctxt_name> [-noconfirm]
lac-service <service_name>
bind address <ip_address>
end
Notes:
 <dst_ctxt_name > is the destination context where you want to configure the LAC service.
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Configuring LNS Peer
Use the following example to configure the LNS peers and load balancing between multiple LNS peers:
configure
context <dst_ctxt_name> [ -noconfirm ]
lac-service <service_name>
tunnel selection-key tunnel-server-auth-id
peer-lns <ip_address> [encrypted] secret <secret> [crypto-map <map_name>
{[encrypted] isakmp-secret <secret> }] [description <text>] [ preference <integer>]
load-balancing { random | balanced | prioritized }
end
Notes:
 <dst_ctxt_name > is the destination context where the LAC service is configured.
Verifying the LAC Service Configuration
These instructions are used to verify the LAC service configuration.
Step 1
Verify that your LAC service configurations were configured properly by entering the following command in Exec
Mode in specific context:
show lac-service name service_name
The output given below is a concise listing of LAC service parameter settings as configured.
Service name: vpn1
Context:
isp1
Bind:
Done
Local IP Address:
192.168.2.1
First Retransmission Timeout:
1 (secs)
Max Retransmission Timeout:
8 (secs)
Max Retransmissions:
5
Max Sessions:
500000
Max Sessions Per Tunnel:
512
Data Sequence Numbers:
Enabled
Max Tunnels: 32000
Tunnel Authentication: Enabled
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▀ Configuring LAC Services
Keep-alive interval:
60
Max Tunnel Challenge Length:
16
Proxy LCP Authentication:
Enabled
Load Balancing:
Random
Service Status:
Started
Newcall Policy:
None
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Modifying PDSN Services for L2TP Support ▀
Modifying PDSN Services for L2TP Support
PDSN service modification is required for compulsory tunneling and optional for attribute-based tunneling.
For attribute-based tunneling, a configuration error could occur such that upon successful authentication, the system
determines that the subscriber session requires L2TP but can not determine the name of the context in which the
appropriate LAC service is configured from the attributes supplied. As a precautionary, a parameter has been added to
the PDSN service configuration options that will dictate the name of the context to use. It is strongly recommended that
this parameter be configured.
This section contains instructions for modifying the PDSN service configuration for either compulsory or attributebased tunneling.
Important: This section provides the minimum instruction set for modifying PDSN service for L2TP support on
the system. For more information on commands that configure additional parameters and options, refer to the LAC
Service Configuration Mode Commands chapter in the Command Line Interface Reference.
To configure the LAC services on system:
Step 1
Modify the PDSN service to support L2TP by associating LAC context and defining tunnel type by applying the
example configuration in the Modifying PDSN Service section.
Step 2
Verify your configuration to modify PDSN service by following the steps in the Verifying the PDSN Service for L2TP
Support section.
Step 3
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Modifying PDSN Service
Use the following example to modify the PDSN service to support L2TP by associating LAC context and defining
tunnel type:
configure
context <source_ctxt_name> [ -noconfirm ]
pdsn-service <pdsn_service_name>
ppp tunnel-context <lac_context_name>
ppp tunnel-type { l2tp | none }
end
Notes:
 <source_ctxt_name > is the name of the source context containing the PDSN service, which you want to
modify for L2TP support.
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▀ Modifying PDSN Services for L2TP Support
 <pdsn_service_name > is the name of the pre-configured PDSN service, which you want to modify for L2TP
support.
 <lac_context_name > is typically the destination context where the LAC service is configured.
Verifying the PDSN Service for L2TP Support
These instructions are used to verify the PDSN service configuration.
Step 1
Verify that your PDSN is configured properly by entering the following command in Exec Mode in specific context:
show pdsn-service name pdsn_service_name
The output of this command is a concise listing of PDSN service parameter settings as configured.
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Modifying APN Templates to Support L2TP ▀
Modifying APN Templates to Support L2TP
This section provides instructions for adding L2TP support for APN templates configured on the system.
Important: This section provides the minimum instruction set for configuring LAC service support on the
system. For more information on commands that configure additional parameters and options, refer to the LAC Service
Configuration Mode Commands chapter in the Command Line Interface Reference.
To configure the LAC services on system:
Step 1
Modify the APN template to support L2TP with LNS server address and other parameters by applying the example
configuration in the Assigning LNS Peer Address in APN Template section.
Step 2
Optional. If L2TP will be used to tunnel transparent IP PDP contexts, configure the APN’s outbound username and
password by applying the example configuration in the Configuring Outbound Authentication section.
Step 3
Verify your APN configuration by following the steps in the Verifying the APN Configuration section.
Step 4
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Assigning LNS Peer Address in APN Template
Use following example to assign LNS server address with APN template:
configure
context <dst_ctxt_name> [-noconfirm]
apn <apn_name>
tunnel l2tp [ peer-address <lns_address> [ [ encrypted ] secret <l2tp_secret> ]
[ preference <integer> ] [ tunnel-context <l2tp_context_name> ] [ local-address
<local_ip_address> ] [ crypto-map <map_name> { [ encrypted ] isakmp-secret
<crypto_secret> } ]
end
Notes:
 <dst_ctxt_name > is the name of system destination context in which the APN is configured.
 <apn_name > is the name of the pre-configured APN template which you want to modify for the L2TP support.
 <lns_address > is the IP address of LNS server node and <local_ip_address > is the IP address of system
which is bound to LAC service.
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▀ Modifying APN Templates to Support L2TP
Configuring Outbound Authentication
Use the following example to configure the LNS peers and load balancing between multiple LNS peers:
configure
context <dst_ctxt_name> [ -noconfirm ]
apn <apn_name>
outbound { [ encrypted ] password <pwd> | username <name> }
end
Notes:
 <dst_ctxt_name > is the destination context where APN template is is configured.
 <apn_name > is the name of the pre-configured APN template which you want to modify for the L2TP support.
Verifying the APN Configuration
These instructions are used to verify the APN configuration.
Step 1
Verify that your APN configurations were configured properly by entering the following command in Exec Mode in
specific context:
show apn name apn_name
The output is a concise listing of APN parameter settings as configured.
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Appendix H
Mobile IP Registration Revocation
This chapter describes Registration Revocation for Mobile-IP and Proxy Mobile-IP and explains how it is configured.
The product administration guides provide examples and procedures for configuration of basic services on the system. It
is recommended that you select the configuration example that best meets your service model and configure the required
elements for that model, as described in this administration guide before using the procedures in this chapter.
Important: This license is enabled by default; however, not all features are supported on all platforms and other
licenses may be required for full functionality as described in this chapter.
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▀ Overview
Overview
Registration Revocation is a general mechanism whereby either the HA or the FA providing Mobile IP functionality to
the same mobile node can notify the other mobility agent of the termination of a binding. This functionality provides the
following benefits:
 Timely release of Mobile IP resources at the FA and/or HA
 Accurate accounting
 Timely notification to mobile node of change in service
Mobile IP Registration Revocation can be triggered at the FA by any of the following:
 Session terminated with mobile node for whatever reason
 Session renegotiation
 Administrative clearing of calls
 Session Manager software task outage resulting in the loss of FA sessions (sessions that could not be recovered)
Important: Registration Revocation functionality is also supported for Proxy Mobile IP. However, only the HA
can initiate the revocation for Proxy-MIP calls.
Mobile IP Registration Revocation can be triggered at the HA by any of the following:
 Administrative clearing of calls
 Inter-Access Gateway handoff. This releases the binding at the previous access gateway/FA
 Session Manager software task outage resulting in the loss of FA sessions (for sessions that could not be
recovered)
 Session Idle timer expiry (when configured to send Revocation)
 Any other condition under which a binding is terminated due to local policy (duplicate IMSI detected, duplicate
home address requested, etc.)
The FA and the HA negotiate Registration Revocation support when establishing a Mobile IP call. Revocation support
is indicated to the Mobile Node (MN) from the FA by setting the 'X' bit in the Agent Advertisement to MN. However
the MN is not involved in negotiating the Revocation for a call or in the Revocation process. It only gets notified about
it. The X bit in the Agent Advertisements is just a hint to the MN that revocation is supported at the FA but is not a
guarantee that it can be negotiated with the HA
At the FA, if revocation is enabled and a FA-HA SPI is configured, the Revocation Support extension is appended to the
RRQ received from the MN and protected by the FA-HA Authentication Extension. At the HA, if the RRQ is accepted,
and the HA supports revocation, the HA responds with an RRP that includes the Revocation Support extension.
Revocation support is considered to be negotiated for a binding when both sides have included a Revocation Support
Extension during a successful registration exchange.
Important: The Revocation Support Extension in the RRQ or RRP must be protected by the FA-HA
Authentication Extension. Therefore, an FA-HA SPI must be configured at the FA and the HA for this to succeed.
If revocation is enabled at the FA, but an FA-HA SPI is not configured at the FA for a certain HA, then FA does not
send Revocation Support Extension for a call to that HA. Therefore, the call may come up without Revocation support
negotiated.
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Overview ▀
If the HA receives an RRQ with Revocation Support Extension, but not protected by FA-HA Auth Extension, it will be
rejected with “FA Failed Authentication” error.
If the FA receives a RRP with Revocation Support Extension, but not protected by FA-HA Auth Extension, it will be
rejected with “HA Failed Authentication” error.
Also note that Revocation support extension is included in the initial, renewal or handoff RRQ/RRP messages. The
Revocation extension is not included in a Deregistration RRQ from the FA and the HA will ignore them in any
Deregistration RRQs received.
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▀ Configuring Registration Revocation
Configuring Registration Revocation
Support for MIP Registration Revocation requires the following configurations:
 FA service(s): Registration Revocation must be enabled and operational parameters optionally configured.
 HA service(s): Registration Revocation must be enabled and operational parameters optionally configured.
Important: These instructions assume that the system was previously configured to support subscriber data
sessions for a core network service with FA and/or an HA according to the instructions described in the respective
product Administration Guide.
Important: Commands used in the configuration samples in this section provide base functionality to the extent
that the most common or likely commands and/or keyword options are presented. In many cases, other optional
commands and/or keyword options are available. Refer to the Command Line Interface Reference for complete
information regarding all commands.
Configuring FA Services
Configure FA services to support MIP Registration Revocation by applying the following example configuration:
configure
context <context_name>
fa-service <fa_service_name>
revocation enable
revocation max-retransmission <number>
revocation retransmission-timeout <time>
end
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
Configuring HA Services
Configure HA services to support MIP Registration Revocation by applying the following example configuration:
configure
context <context_name>
ha-service <ha_service_name>
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Configuring Registration Revocation ▀
revocation enable
revocation max-retransmission <number>
revocation retransmission-timeout <time>
end
Save your configuration to flash memory, an external memory device, and/or a network location using the Exec mode
command save configuration . For additional information on how to verify and save configuration files, refer to the
System Administration Guide and the Command Line Interface Reference.
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Appendix I
Multi-Protocol Label Switching (MPLS) Support
This chapter describes the system’s support for BGP/MPLS VPN and explains how it is configured. The product
administration guides provide examples and procedures for configuration of basic services on specific systems. It is
recommended that you select the configuration example that best meets your service model and configure the required
elements for that model, as described in the respective product administration guide, before using the procedures in this
chapter.
When enabled through a feature license key, the system supports MPLS to provide a VPN connectivity from the system
to the corporate’s network.
Important: This release provides BGP/MPLS VPN for directly connected PE routers only.
MP-BGP is used to negotiate the routes and segregate the traffic for the VPNs. The network node learns the VPN routes
from the connected Provider Edge (PE), while the PE populates its routing table with the routes provided by the network
functions.
This chapter includes following sections:
 Overview
 Supported Standards
 Supported Networks and Platforms
 Licenses
 Benefits
 Configuring BGP/MPLS VPN with Static Labels
 Configuring BGP/MPLS VPN with Dynamic Labels
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▀ Overview
Overview
As seen in the following scenario, the chassis can be deployed as a router while supporting BGP/MPLS-VPN in a
network.
 Chassis as MPLS-Customer Edge (MPLS-CE) connecting to Provider Edge (PE)
 Chassis as MPLS-Customer Edge (MPLS-CE) connecting to Autonomous System Border Router (ASBR)
Chassis as MPLS-CE Connecting to PE
Figure 58.
Chassis as MPLS-CE Connected to PE
The system in this scenario uses static/dynamic MPLS labels for ingress and egress traffic. For configuration
information on static label, refer to the Configuring BGP/MPLS VPN with Static Labels section and refer Configuring
BGPMPLS VPN with Dynamic Labels for dynamic lable configuration.
The system is in a separate autonomous system (AS) from the Provider Edge (PE). It communicates with the PE and all
VPN routes are exchanged over MP-BGP. Routes belonging to different VPNs are logically separated, using separate
virtual route forwarding tables (VRFs).
Routes for each VPN are advertised as VPN-IPv4 routes, where route distinguishers are prepended to regular IPv4
routes to allow them to be unique within the routing table. Route targets added to the BGP extended community
attributes identify different VPN address spaces. The particular upstream BGP peer routing domain (VPN), from which
a route is to be imported by the downstream peer into an appropriate VRF, is identified with an extended community in
the advertised NLRI.
A unique label is also received or advertised for every VPN route.
The Customer Edge (CE) also advertises routes to the PE using NLRIs that include route distinguishers to differentiate
VPNs, an extended community to identify VRFs, and a MPLS-lable, which will later be used to foward data traffic.
There is a single MPLS-capable link between the CE and the PE. MP-BGP communicates across this link as a TCP
session over IP. Data packets are sent bidirectionally as MPLS encapsulated packets.
This solution does not use any MPLS protocols. The MPLS label corresponding to the immediate upstream neighbor
can be statically configured on the downstream router, and similarly in the reverse direction.
When forwarding subscriber packets in the upstream direction to the PE, the CE encapsulates packets with M PLS
headers that identify the upstream VRF (the label sent with the NLRI) and the immediate next hop. When the PE
receives a packet it swaps the label and forward.
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Overview ▀
The CE does not run any MPLS protocol (LDP or RSVP-TE).
When receiving data packets in the downstream direction from the PE, the label is checked to identify the destination
VRF. Then the packet is de-encapsulated into an IP packet and sent to the session subsystem for processing.
Important: MPLS ping/trace route debugging facilities are not supported.
Chassis as MPLS-CE Connected to ASBR
Figure 59.
Chassis as MPLS-CE Connected to ASBR
The system in this scenario uses static/dynamic MPLS labels for ingress and egress traffic. For configuration
information on static label, refer to the Configuring BGP/MPLS VPN with Static Labels section and refer Configuring
BGPMPLS VPN with Dynamic Labels for dynamic lable configuration.
This scenario differs from the MPLS-CE with PE scenario in terms of peer functionality even though MPLS-CE
functionality does not change. Like the MPLS-CE with PE scenario, MPLS-CE system maintains VRF routes in various
VRFs and exchanges route information with peer over MP-eBGP session.
The peer in this scenario is not a PE router but an Autonomous System Border Router (ASBR). The ASBR does not
need to maintain any VRF configuration. The PE routers use IBGP to redistribute labeled VPN-IPv4 routes either to an
ASBR or to a route reflector (of which the ASBR is a client). The ASBR then uses the eBGP to redistribute those
labeled VPN-IPv4 routes to an MPLS-CE in another AS. Because of the eBGP connection, the ASBR changes the nexthop and labels the routes learned from the iBGP peers before advertising to the MPLS-CE. The MPLS-CE is directly
connected to the eBGP peering and uses only the the MP-eBGP to advertise and learn routes. The MPLS-CE
pushes/pops a single label to/from the ASBR, which is learned over the MP-eBGP connection. This scenario avoids the
configuration of VRFs on the PE, which have already been configured on the MPLS-CE.
Engineering Rules
 Up to 250 virtual routing tables per context.
 Up to 5000 “host routes” spread across multiple VRFs per BGP process. Limited to 6000 pool routes per chassis.
 Up to 1024 VRFs per chassis.
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▀ Supported Standards
Supported Standards
Support for the following standards and requests for comments (RFCs) have been added with this interface support:
 RFC 4364, BGP/MPLS IP VPNs
 RFC 3032, MPLS Label Stack Encoding
Important: One or more sections of above mentioned IETF are partially supported for this feature. For more
information on Statement of Compliance, contact your Cisco account representative.
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Supported Networks and Platforms ▀
Supported Networks and Platforms
This feature supports all ASR5x00 platforms with StarOS Release 9.0 or later running with network function services.
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▀ Licenses
Licenses
Multi-protocol label switching (MPLS) is a licensed Cisco feature. A separate feature license may be required. Contact
your Cisco account representative for detailed information on specific licensing requirements. For information on
installing and verifying licenses, refer to the Managing License Keys section of the Software Management Operations
chapter in the System Administration Guide.
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Benefits ▀
Benefits
MPLS provides networks with a more efficient way to manage applications and move information between locations.
MPLS prioritizes network traffic, so administrators can specify which applications should move across the network
ahead of others.
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▀ Configuring BGP/MPLS VPN with Static Labels
Configuring BGP/MPLS VPN with Static Labels
This section describes the procedures required to configure the system as an MPLS-CE to interact with a PE with static
MPLS label support.
The base configuration, as described in the Routing chapter in this guide, must be completed prior to attempt the
configuration procedure described below.
Important: The feature described in this chapter is a licensed Cisco feature. A separate feature license may be
required. Contact your Cisco account representative for detailed information on specific licensing requirements.
Important: Commands used in the configuration samples in this section provide base functionality to the extent
that the most common or likely commands and/or keyword options are presented. In many cases, other optional
commands and/or keyword options are available. Refer to the Command Line Interface Reference for complete
information regarding all commands.
To configure the system for BGP/MPLS VPN:
Step 1
Create a VRF on the router and assign a VRF name by applying the example configurati on in the Create VRF with
Route-distinguisher and Route-target section.
Step 2
Set the neighbors and address family to exchange routing information and establish BGP peering with a peer router by
applying the example configuration in the Set Neighbors and Enable VPNv4 Route Exchange section.
Step 3
Configure the address family and redistribute the connected routes domains into BGP by applying the example
configuration in the Configure Address Family and Redistribute Connected Routes section. This takes any routes from
another protocol and redistributes them to BGP neighbors using the BGP protocol.
Step 4
Configure IP Pools with MPLS labels for input and output by applying the example configuration in the Configure IP
Pools with MPLS Labels section.
Step 5
Optional. Bind DHCP service to work with MPLS labels for input and output in corporate networks by applying the
example configuration in the Bind DHCP Service for Corporate Servers section.
Step 6
Optional. Bind AAA/RADIUS server group in corporate network to work with MPLS labels for input and output by
applying the example configuration in the Bind AAA Group for Corporate Servers section.
Step 7
Save your configuration as described in the System Administration Guide.
Create VRF with Route-distinguisher and Route-target
Use this example to first create a VRF on the router and assign a VRF name. The second ip vrf command creates the
route-distinguisher and route-target.
configure
context <context_name> -noconfirm
ip vrf <vrf_name>
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router bgp <as_number>
ip vrf <vrf_name>
route-distinguisher {<as_value> | <ip_address>} <rt_value>
route-target export {<as_value> | <ip_address>} <rt_value>
end
Set Neighbors and Enable VPNv4 Route Exchange
Use this example to set the neighbors and address family to exchange VPNv4 routing information with a peer router.
configure
context <context_name>
router bgp <as_number>
neighbor <ip_address> remote-as <AS_num>
address-family vpnv4
neighbor <ip_address> activate
neighbor <ip_address> send-community both
exit
interface <bind_intfc_name>
ip address <ip_addr_mask_combo>
end
Configure Address Family and Redistributed Connected Routes
Use this example to configure the address-family and to redistribute the connected routes or IP pools into BGP.
This takes any routes from another protocol and redistributes them using the BGP protocol.
configure
context <context_name>
router bgp <as_number>
address-family ipv4 <type> vrf <vrf_name>
redistribute connected
end
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▀ Configuring BGP/MPLS VPN with Static Labels
Configure IP Pools with MPLS Labels
Use this example to configure IP Pools with MPLS labels for input and output.
configure
context <context_name> -noconfirm
ip pool <name> <ip_addr_mask_combo> private vrf <vrf_name> mpls-label input
<in_label_value> output <out_label_value1> nexthop-forwarding-address
<ip_addr_bgp_neighbor>
end
Bind DHCP Service for Corporate Servers
Use this example to bind DHCP service with MPLS labels for input and output in Corporate network.
configure
context <dest_ctxt_name>
interface <intfc_name> loopback
ip vrf forwarding <vrf_name>
ip address <bind_ip_address subnet_mask>
exit
dhcp-service <dhcp_svc_name>
dhcp ip vrf <vrf_name>
bind address <bind_ip_address> [ nexthop-forwarding-address
<nexthop_ip_address> [ mpls-label input <in_mpls_label_value> output
<out_mpls_label_value1> [ <out_mpls_label_value2> ]]]
dhcp server <ip_address>
end
Notes:
 To ensure proper operation, DHCP functionality should be configured within a destination context.
 Optional keyword nexthop-forwarding-address <ip_address > mpls-label input
<in_mpls_label_value> output < <out_mpls_label_value1> applies DHCP over MPLS traffic.
Bind AAA Group for Corporate Servers
Use this example to bind AAA server groups with MPLS labels for input and output in Corporate network.
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Configuring BGP/MPLS VPN with Static Labels ▀
configure
context <dest_ctxt_name>
aaa group <aaa_grp_name>
radius ip vrf <vrf_name>
radius attribute nas-ip-address address <nas_address> nexthop-forwardingaddress <ip_address> mpls-label input <in_mpls_label_value> output <
<out_mpls_label_value1>
radius server <ip_address> encrypted key <encrypt_string> port
<iport_num>
end
Notes:
 aaa_grp_name is a pre-configured AAA server group configured in Context Configuration mode. Refer AAA
Interface Administration Reference for more information on AAA group configuration.
 Optional keyword nexthop-forwarding-address <ip_address > mpls-label input
<in_mpls_label_value> output < <out_mpls_label_value1> associates AAA group for MPLS
traffic.
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▀ Configuring BGP/MPLS VPN with Dynamic Labels
Configuring BGP/MPLS VPN with Dynamic Labels
This section describes the procedures required to configure the system as an MPLS-CE to interact with a PE with
dynamic MPLS label support.
The base configuration, as described in the Routing chapter in this guide, must be completed prior to attempt the
configuration procedure described below.
Important: The features described in this chapter is an enhanced feature and need enhanced feature license. This
support is only available if you have purchased and installed particular feature support license on your chassis.
Important: Commands used in the configuration samples in this section provide base functionality to the extent
that the most common or likely commands and/or keyword options are presented. In many cases, other optional
commands and/or keyword options are available. Refer to the Command Line Interface Reference for complete
information regarding all commands.
To configure the system for BGP/MPLS VPN:
Step 1
Create a VRF on the router and assign a VRF name by applying the example configuration in the Create VRF with
Route-distinguisher and Route-target section.
Step 2
Set the neighbors and address family to exchange routing information and establish BGP peering with a peer router by
applying the example configuration in the Set Neighbors and Enable VPNv4 Route Exchange section.
Step 3
Configure the address family and redistribute the connected routes domains into BGP by applying the example
configuration in the Configure Address Family and Redistribute Connected Routes section. This takes any routes from
another protocol and redistributes them to BGP neighbors using the BGP protocol.
Step 4
Configure IP Pools with dynamic MPLS labels by applying the example configuration in the Configure IP Pools with
MPLS Labels section.
Step 5
Optional. Bind DHCP service to work with dynamic MPLS labels in corporate networks by applying the example
configuration in the Bind DHCP Service for Corporate Servers section.
Step 6
Optional. Bind AAA/RADIUS server group in corporate network to work with dynamic MPLS labels by applying the
example configuration in the Bind AAA Group for Corporate Servers section.
Step 7
Optional. Modify the configured IP VRF, which is configured to support basic MPLS functionality, for mapping
between DSCP bit value and experimental (EXP) bit value in MPLS header for ingress and egress traffic by applying
the example configuration in the DSCP and EXP Bit Mapping section.
Step 8
Save your configuration as described in the System Administration Guide.
Create VRF with Route-distinguisher and Route-target
Use this example to first create a VRF on the router and assign a VRF name. The second ip vrf command creates the
route-distinguisher and route-target.
configure
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Configuring BGP/MPLS VPN with Dynamic Labels ▀
context <context_name> -noconfirm
ip vrf <vrf_name>
router bgp <as_number>
ip vrf <vrf_name>
route-distinguisher {<as_value> | <ip_address>} <rt_value>
route-target export {<as_value> | <ip_address>} <rt_value>
route-target import {<as_value> | <ip_address>} <rt_value>
end
Notes:
 If export and improt route targets are the same, alternate command route-target both {<as_value > |
<ip_address > } <rt_value > can be used in place of route-target import and route-target
export commands.
Set Neighbors and Enable VPNv4 Route Exchange
Use this example to set the neighbors and address family to exchange VPNv4 routing information with a peer router.
configure
context <context_name>
mpls bgp forwarding
router bgp <as_number>
neighbor <ip_address> remote-as <AS_num>
address-family vpnv4
neighbor <ip_address> activate
neighbor <ip_address> send-community both
exit
interface <bind_intfc_name>
ip address <ip_addr_mask_combo>
end
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▀ Configuring BGP/MPLS VPN with Dynamic Labels
Configure Address Family and Redistributed Connected Routes
Use this example to configure the address-family and to redistribute the connected routes or IP pools into BGP.
This takes any routes from another protocol and redistributes them using the BGP protocol.
configure
context <context_name>
router bgp <as_number>
address-family ipv4 <type> vrf <vrf_name>
redistribute connected
end
Configure IP Pools with MPLS Labels
Use this example to configure IP Pools with dynamic MPLS labels.
configure
context <context_name> -noconfirm
ip pool <name> <ip_addr_mask_combo> private vrf <vrf_name>
end
Bind DHCP Service for Corporate Servers
Use this example to bind DHCP service with dynamic MPLS labels in Corporate network.
configure
context <dest_ctxt_name>
interface <intfc_name> loopback
ip vrf forwarding <vrf_name>
ip address <bind_ip_address subnet_mask>
exit
dhcp-service <dhcp_svc_name>
dhcp ip vrf <vrf_name>
bind address <bind_ip_address>
dhcp server <ip_address>
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Configuring BGP/MPLS VPN with Dynamic Labels ▀
end
Notes:
 To ensure proper operation, DHCP functionality should be configured within a destination context.
Bind AAA Group for Corporate Servers
Use this example to bind AAA server groups with dynamic MPLS labels in Corporate network.
configure
context <dest_ctxt_name>
aaa group <aaa_grp_name>
radius ip vrf <vrf_name>
radius attribute nas-ip-address address <nas_address>
radius server <ip_address> encrypted key <encrypt_string> port
<iport_num>
end
Notes:
 aaa_grp_name is a pre-configured AAA server group configured in Context Configuration mode. Refer AAA
Interface Administration Reference for more information on AAA group configuration.
DSCP and EXP Bit Mapping
Use this example to modify the configured IP VRF to support QoS mapping.
configure
context <context_name>
ip vrf <vrf_name>
mpls map-dscp-to-exp dscp <dscp_bit_value> exp <exp_bit_value>
mpls map-exp-to-dscp exp <exp_bit_value> dscp <dscp_bit_value>
end
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Appendix J
Proxy-Mobile IP
This chapter describes system support for Proxy Mobile IP and explains how it is configured. The product
administration guides provide examples and procedures for configuration of basic services on the system. It is
recommended that you select the configuration example that best meets your service model before using the procedures
in this chapter.
Proxy Mobile IP provides a mobility solution for subscribers with mobile nodes (MNs) capable of supporting only
Simple IP.
This chapter includes the following sections:
 Overview
 How Proxy Mobile IP Works in 3GPP2 Network
 How Proxy Mobile IP Works in 3GPP Network
 How Proxy Mobile IP Works in WiMAX Network
 How Proxy Mobile IP Works in a WiFi Network with Multiple Authentication
 Configuring Proxy Mobile-IP Support
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▀ Overview
Overview
Proxy Mobile IP provides mobility for subscribers with MNs that do not support the Mobile IP protocol stack.
Important: Proxy Mobile IP is a licensed Cisco feature. A separate feature license may be required. Contact your
Cisco account representative for detailed information on specific licensing requirements. For information on installing
and verifying licenses, refer to the Managing License Keys section of the Software Management Operations chapter in
the System Administration Guide.
The Proxy Mobile IP feature is supported for various products. The following table indicates the products on which the
feature is supported and the relevant sections within the chapter that pertain to that product.
Table 28.
Applicable Products and Relevant Sections
Applicable Product(s)
PDSN
GGSN
Refer to Sections

Proxy Mobile IP in 3GPP2 Service

How Proxy Mobile IP Works in 3GPP2 Network

Configuring FA Services

Configuring Proxy MIP HA Failover

Configuring HA Services

Configuring Subscriber Profile RADIUS Attributes

RADIUS Attributes Required for Proxy Mobile IP

Configuring Local Subscriber Profiles for Proxy-MIP on a PDSN

Configuring Default Subscriber Parameters in Home Agent Context

Proxy Mobile IP in 3GPP Service

How Proxy Mobile IP Works in 3GPP Network

Configuring FA Services

Configuring Proxy MIP HA Failover

Configuring HA Services

Configuring Subscriber Profile RADIUS Attributes

RADIUS Attributes Required for Proxy Mobile IP

Configuring Default Subscriber Parameters in Home Agent Context

Configuring APN Parameters
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Overview ▀
Applicable Product(s)
ASN GW
PDIF
Refer to Sections

Proxy Mobile IP in WiMAX Service

How Proxy Mobile IP Works in WiMAX Network

Configuring FA Services

Configuring Proxy MIP HA Failover

Configuring HA Services

Configuring Subscriber Profile RADIUS Attributes

RADIUS Attributes Required for Proxy Mobile IP

Configuring Default Subscriber Parameters in Home Agent Context

How Proxy Mobile IP Works in a WiFi Network with Multiple Authentication

Configuring FA Services

Configuring Proxy MIP HA Failover

Configuring HA Services

Configuring Subscriber Profile RADIUS Attributes

RADIUS Attributes Required for Proxy Mobile IP

Configuring Default Subscriber Parameters in Home Agent Context
Proxy Mobile IP in 3GPP2 Service
For subscriber sessions using Proxy Mobile IP, R-P and PPP sessions get established between the MN and the PDSN as
they would for a Simple IP session. However, the PDSN/FA performs Mobile IP operations with an HA (identified by
information stored in the subscriber’s profile) on behalf of the MN (i.e. the MN is only responsible for maintaining the
Simple IP PPP session with PDSN).
The MN is assigned an IP address by either the PDSN/FA or the HA. Regardless of its source, the address is stored in a
mobile binding record (MBR) stored on the HA. Therefore, as the MN roams through the service provider’s network,
each time a hand-off occurs, the MN will continue to use the same IP address stored in the MBR on the HA.
Note that unlike Mobile IP-capable MNs that can perform multiple sessions over a single PPP link, Proxy Mobile IP
allows only a single session over the PPP link. In addition, simultaneous Mobile and Simple IP sessions will not be
supported for an MN by the FA that is currently facilitating a Proxy Mobile IP session for the MN.
The MN is assigned an IP address by either the HA, a AAA server, or on a static-basis. The address is stored in a mobile
binding record (MBR) stored on the HA. Therefore, as the MN roams through the service provider’s network, each time
a hand-off occurs, the MN will continue to use the same IP address stored in the MBR on the HA.
Proxy Mobile IP in 3GPP Service
For IP PDP contexts using Proxy Mobile IP, the MN establishes a session with the GGSN as it normally would.
However, the GGSN/FA performs Mobile IP operations with an HA (identified by information stored in the subscriber’s
profile) on behalf of the MN (i.e. the MN is only responsible for maintaining the IP PDP context with the GGSN, no
Agent Advertisement messages are communicated with the MN).
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The MN is assigned an IP address by either the HA, a AAA server, or on a static-basis. The address is stored in a mobile
binding record (MBR) stored on the HA. Therefore, as the MN roams through the service provider’s network, each time
a hand-off occurs, the MN will continue to use the same IP address stored in the MBR on the HA.
Proxy Mobile IP can be performed on a per-subscriber basis based on information contained in their user profile, or for
all subscribers facilitated by a specific APN. In the case of non-transparent IP PDP contexts, attributes returned from the
subscriber’s profile take precedence over the configuration of the APN.
Proxy Mobile IP in WiMAX Service
For subscriber sessions using Proxy Mobile subscriber sessions get established between the MN and the ASN GW as
they would for a Simple IP session. However, the ASN GW/FA performs Mobile IP operations with an HA (identified
by information stored in the subscriber’s profile) on behalf of the MN (i.e. the MN is only responsible for maintaining
the Simple IP subscriber session with ASN GW).
The MN is assigned an IP address by either the ASN GW/FA or the HA. Regardless of its source, the address is stored
in a mobile binding record (MBR) stored on the HA. Therefore, as the MN roams through the service provider’s
network, each time a hand-off occurs, the MN will continue to use the same IP address stored in the MBR on the HA.
Note that unlike Mobile IP-capable MNs that can perform multiple sessions over a single session link, Proxy Mobile IP
allows only a single session over the session link. In addition, simultaneous Mobile and Simple IP sessions will not be
supported for an MN by the FA that is currently facilitating a Proxy Mobile IP session for the MN.
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How Proxy Mobile IP Works in 3GPP2 Network
This section contains call flows displaying successful Proxy Mobile IP session setup scenarios. There are multiple
scenarios that are dependant on how the MN receives an IP address. The following scenarios are described:
 Scenario 1: The AAA server that authenticates the MN at the PDSN allocates an IP address to the MN. Note
that the PDSN does not allocate an address from its IP pools.
 Scenario 2: The HA assigns an IP address to the MN from one of its locally configured dynamic pools.
Scenario 1: AAA server and PDSN/FA Allocate IP Address
The following figure and table display and describe a call flow in which the M N receives its IP address from the AAA
server and PDSN/FA.
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Figure 60.
AAA/PDSN Assigned IP Address Proxy Mobile IP Call Flow
Table 29. AAA/PDSN Assigned IP Address Proxy Mobile IP Call Flow Description
Step
Description
1
Mobile Node (MN) secures a traffic channel over the airlink with the RAN through the BSC/PCF.
2
The PCF and PDSN/FA establish the R-P interface for the session.
3
The PDSN/FA and MN negotiate Link Control Protocol (LCP).
4
Upon successful LCP negotiation, the MN sends a PPP Authentication Request message to the PDSN/FA.
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Step
Description
5
The PDSN/FA sends an Access Request message to the RADIUS AAA server.
6
The RADIUS AAA server successfully authenticates the subscriber and returns an Access Accept message to the
PDSN/FA. The Accept message may contain various attributes to be assigned to the MN including the MN’s Home
Address (IP address) and the IP address of the HA to use.
7
The PDSN/FA sends a PPP Authentication Response message to the MN.
8
The MN sends an Internet Protocol Control Protocol (IPCP) Configuration Request message to the PDSN/FA with an MN
address of 0.0.0.0.
9
The PDSN/FA forwards a Proxy Mobile IP Registration Request message to the HA. The message includes fields such as
the MN’s home address, the IP address of the FA (the care-of-address), and the FA-HA extension (security parameter index
(SPI)).
10
While the FA is communicating with the HA, the MN may send additional IPCP Configuration Request messages.
11
The HA responds with a Proxy Mobile IP Registration Response after validating the home address against it’s pool. The
HA also creates a mobile binding record (MBR) for the subscriber session.
12
The MN and the PDSN/FA negotiate IPCP. The result is that the MN is assigned the home address originally specified by
the AAA server.
13
While the MN and PDSN/FA are negotiating IPCP, the HA and AAA server initiate accounting.
14
Upon completion of the IPCP negotiation, the PDSN/FA and AAA server initiate accounting fully establishing the session
allowing the MN to send/receive data to/from the PDN.
15
Upon completion of the session, the MN sends an LCP Terminate Request message to the PDSN to end the PPP session.
16
The PDSN/FA sends a Proxy Mobile IP De-registration Request message to the HA.
17
The PDSN/FA send an LCP Terminate Acknowledge message to the MN ending the PPP session.
18
The HA sends a Proxy Mobile IP De-Registration Response message to the FA terminating the Pi interface
19
The PDSN/FA and the PCF terminate the R-P session.
20
The HA and the AAA server stop accounting for the session.
21
The PDSN and the AAA server stop accounting for the session.
Scenario 2: HA Allocates IP Address
The following figure and table display and describe a call flow in which the MN receives its IP address from the HA.
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Figure 61.
HA Assigned IP Address Proxy Mobile IP Call Flow
Table 30. HA Assigned IP Address Proxy Mobile IP Call Flow Description
Step
Description
1
Mobile Node (MN) secures a traffic channel over the airlink with the RAN through the BSC/PCF.
2
The PCF and PDSN/FA establish the R-P interface for the session.
3
The PDSN/FA and MN negotiate Link Control Protocol (LCP).
4
Upon successful LCP negotiation, the MN sends a PPP Authentication Request message to the PDSN/FA.
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Step
Description
5
The PDSN/FA sends an Access Request message to the RADIUS AAA server.
6
The RADIUS AAA server successfully authenticates the subscriber and returns an Access Accept message to the
PDSN/FA. The Accept message may contain various attributes to be assigned to the MN including the IP address of the
HA to use.
7
The PDSN/FA sends a PPP Authentication Response message to the MN.
8
The MN sends an Internet Protocol Control Protocol (IPCP) Configuration Request message to the PDSN/FA with an MN
address of 0.0.0.0.
9
The PDSN/FA forwards a Proxy Mobile IP Registration Request message to the HA. The message includes fields such as a
Home Address indicator of 0.0.0.0, the IP address of the FA (the care-of-address), the IP address of the FA (the care-ofaddress), and the FA-HA extension (security parameter index (SPI)).
10
While the FA is communicating with the HA, the MN may send additional IPCP Configuration Request messages.
11
The HA responds with a Proxy Mobile IP Registration Response. The response includes an IP address from one of its
locally configured pools to assign to the MN (its Home Address). The HA also creates a mobile binding record (MBR) for
the subscriber session.
12
The MN and the PDSN/FA negotiate IPCP. The result is that the MN is assigned the home address originally specified by
the AAA server.
13
While the MN and PDSN/FA are negotiating IPCP, the HA and AAA server initiate accounting.
14
Upon completion of the IPCP negotiation, the PDSN/FA and AAA server initiate accounting fully establishing the session
allowing the MN to send/receive data to/from the PDN.
15
Upon completion of the session, the MN sends an LCP Terminate Request message to the PDSN to end the PPP session.
16
The PDSN/FA sends a Proxy Mobile IP De-registration Request message to the HA.
17
The PDSN/FA send an LCP Terminate Acknowledge message to the MN ending the PPP session.
18
The HA sends a Proxy Mobile IP De-Registration Response message to the FA terminating the Pi interface
19
The PDSN/FA and the PCF terminate the R-P session.
20
The HA and the AAA server stop accounting for the session.
21
The PDSN and the AAA server stop accounting for the session.
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How Proxy Mobile IP Works in 3GPP Network
This section contains call flows displaying successful Proxy Mobile IP session setup scenarios in 3GPP network.
The following figure and the text that follows describe a a sample successful Proxy Mobile IP session setup call flow in
3GGP service.
Figure 62.
Proxy Mobile IP Call Flow in 3GPP
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Table 31. Proxy Mobile IP Call Flow in 3GPP Description
Step
Description
1
The mobile station (MS) goes through the process of attaching itself to the GPRS/UMTS network.
2
The terminal equipment (TE) aspect of the MS sends AT commands to the mobile terminal (MT) aspect of the MS to place
it into PPP mode.
The Link Control Protocol (LCP is then used to configure the Maximum-Receive Unit size and the authentication protocol
(Challenge-Handshake Authentication Protocol (CHAP), Password Authentication Protocol (PAP), or none). If CHAP or
PAP is used, the TE will authenticate itself to the MT, which, in turn, stores the authentication information.
Upon successful authentication, the TE sends an Internet Protocol Control Protocol (IPCP) Configure-Request message to
the MT. The message will either contain a static IP address to use or request that one be dynamically assigned.
3
The MS sends an Activate PDP Context Request message that is received by an SGSN. The message contains information
about the subscriber such as the Network layer Service Access Point Identifier (NSAPI), PDP Type, PDP Address, Access
Point Name (APN), quality of service (QoS) requested, and PDP configuration options.
4
The SGSN authenticates the request message and sends a Create PDP Context Request message to a GGSN using the
GPRS Tunneling Protocol (GTPC, “C” indicates the control signalling aspect of the protocol). The recipient GGSN is
selected based on either the request of the MS or is automatically selected by the SGSN. The message consists of various
information elements including: PDP Type, PDP Address, APN, charging characteristics, and tunnel endpoint identifier
(TEID, if the PDP Address was static).
5
The GGSN determines if it can facilitate the session (in terms of memory or CPU resources, configuration, etc.) and creates
a new entry in its PDP context list and provides a Charging ID for the session.
From the APN specified in the message, the GGSN determines whether or not the subscriber is to be authenticated, if Proxy
Mobile IP is to be supported for the subscriber, and if so, the IP address of the HA to contact.
Note that Proxy Mobile IP support can also be determined by attributes in the user’s profile. Attributes in the user’s profile
supersede APN settings.
If authentication is required, the GGSN attempts to authenticate the subscriber locally against profiles stored in memory or
send a RADIUS Access-Request message to a AAA server.
6
If the GGSN authenticated the subscriber to a AAA server, the AAA server responds with a RADIUS Access-Accept
message indicating successful authentication and any attributes for handling the subscriber PDP context.
7
If Proxy Mobile IP support was either enabled in the APN or in the subscrib er’s profile, the GGSN/FA forwards a Proxy
Mobile IP Registration Request message to the specified HA. The message includes such things as the MS’s home address,
the IP address of the FA (the care-of-address), and the FA-HA extension (security parameter index (SPI)).
8
The HA responds with a Proxy Mobile IP Registration Response. The response includes an IP address from one of its
locally configured pools to assign to the MS (its Home Address). The HA also creates a mobile binding record (MBR) for
the subscriber session.
9
The HA sends an RADIUS Accounting Start request to the AAA server which the AAA server responds to.
10
The GGSN replies with an affirmative Create PDP Context Response using GTPC. The response will contain information
elements such as the PDP Address representing either the static address requested by the MS or the address assigned by the
GGSN, the TEID used to reference PDP Address, and PDP configuration options specified by the GGSN.
11
The SGSN returns an Activate PDP Context Accept message to the MS. The message includes response to the
configuration parameters sent in the initial request.
12
The MT, will respond to the TE’s IPCP Config-request with an IPCP Config-Ack message.
The MS can now send and receive data to or from the PDN until the session is closed or times out. Note that for Mobile IP,
only one PDP context is supported for the MS.
13
The FA periodically sends Proxy Mobile IP Registration Request Renewal messages to the HA. The HA sends responses
for each request.
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Step
Description
14
The MS can terminate the data session at any time. To terminate the session, the MS sends a Deactivate PDP Context
Request message that is received by the SGSN.
15
The SGSN sends a Delete PDP Context Request message to the GGSN facilitating the data session. The message includes
the information elements necessary to identify the PDP context (i.e., TEID, and NSAPI).
16
The GGSN removes the PDP context from memory and the FA sends a Proxy Mobile IP Deregistration Request message to
the HA.
17
The GGSN returns a Delete PDP Context Response message to the SGSN.
18
The HA replies to the FA with a Proxy Mobile IP Deregistration Request Response.
19
The HA sends an RADIUS Accounting Stop request to the AAA server which the AAA server responds to.
20
The SGSN returns a Deactivate PDP Context Accept message to the MS.
21
The GGSN delivers the GGSN Charging Detail Records (G-CDRs) to a charging gateway (CG) using GTP Prime (GTPP).
Note that, though not shown in this example, the GGSN could optionally be configured to send partial CDRs while the PDP
context is active.
22
For each accounting message received from the GGSN, the CG responds with an acknowledgement.
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How Proxy Mobile IP Works in WiMAX Network
This section contains call flows displaying successful Proxy Mobile IP session setup scenarios. There are multiple
scenarios that are dependant on how the MN receives an IP address. The following scenarios are described:
 Scenario 1: The AAA server that authenticates the MN at the ASN GW allocates an IP address to the MN. Note
that the ASN GW does not allocate an address from its IP pools.
 Scenario 2: The HA assigns an IP address to the MN from one of its locally configured dynamic pools.
Scenario 1: AAA server and ASN GW/FA Allocate IP Address
The following figure and table display and describe a call flow in which the MN receives its IP address from the AAA
server and ASN GW/FA.
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Figure 63.
AAA/ASN GW Assigned IP Address Proxy Mobile IP Call Flow
Table 32. AAA/ASN GW Assigned IP Address Proxy Mobile IP Call Flow Description
Step
Description
1
Mobile Node (MN) secures a traffic channel over the airlink with the BS.
2
The BS and ASN GW/FA establish the R6 interface for the session.
3
The ASN GW/FA and MN negotiate Link Control Protocol (LCP).
4
Upon successful LCP negotiation, the MN sends a PPP Authentication Request message to the ASN GW/FA.
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Step
Description
5
The ASN GW/FA sends an Access Request message to the RADIUS AAA server.
6
The RADIUS AAA server successfully authenticates the subscriber and returns an Access Accept message to the ASN
GW/FA. The Accept message may contain various attributes to be assigned to the MN including the MN’s Home Address
(IP address) and the IP address of the HA to use.
7
The ASN GW/FA sends a EAP Authentication Response message to the MN.
8
The MN sends an Internet Protocol Control Protocol (IPCP) Configuration Request message to the ASN GW/FA with an
MN address of 0.0.0.0.
9
The ASN GW/FA forwards a Proxy Mobile IP Registration Request message to the HA. The message includes fields such
as the MN’s home address, the IP address of the FA (the care-of-address), and the FA-HA extension (security parameter
index (SPI)).
10
While the FA is communicating with the HA, the MN may send additional IPCP Configuration Request messages.
11
The HA responds with a Proxy Mobile IP Registration Response after validating the home address against it’s pool. The
HA also creates a mobile binding record (MBR) for the subscriber session.
12
The MN and the ASN GW/FA negotiate IPCP. The result is that the MN is assigned the home address originally specified
by the AAA server.
13
While the MN and ASN GW/FA are negotiating IPCP, the HA and AAA server initiate accounting.
14
Upon completion of the IPCP negotiation, the ASN GW/FA and AAA server initiate accounting fully establishing the
session allowing the MN to send/receive data to/from the PDN.
15
Upon completion of the session, the MN sends an LCP Terminate Request message to the ASN GW to end the subscriber
session.
16
The PDSN/FA sends a Proxy Mobile IP De-registration Request message to the HA.
17
The ASN GW/FA send an LCP Terminate Acknowledge message to the MN ending the subscriber session.
18
The HA sends a Proxy Mobile IP De-Registration Response message to the FA terminating the R3 interface
19
The ASN GW/FA and the BS terminate the R6 session.
20
The HA and the AAA server stop accounting for the session.
21
The ASN GW and the AAA server stop accounting for the session.
Scenario 2: HA Allocates IP Address
The following figure and table display and describe a call flow in which the MN receives its IP address from the HA.
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Figure 64.
HA Assigned IP Address Proxy Mobile IP Call Flow
Table 33. HA Assigned IP Address Proxy Mobile IP Call Flow Description
Step
Description
1
Mobile Node (MN) secures a traffic channel over the airlink with the BS.
2
The BS and ASN GW/FA establish the R6 interface for the session.
3
The ASN GW/FA and MN negotiate Link Control Protocol (LCP).
4
Upon successful LCP negotiation, the MN sends an EAP Authentication Request message to the ASN GW/FA.
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Step
Description
5
The ASN GW/FA sends an Access Request message to the RADIUS AAA server.
6
The RADIUS AAA server successfully authenticates the subscriber and returns an Access Accept message to the ASN
GW/FA. The Accept message may contain various attributes to be assigned to the MN including the IP address of the HA
to use.
7
The ASN GW/FA sends an EAP Authentication Response message to the MN.
8
The MN sends an Internet Protocol Control Protocol (IPCP) Configuration Request message to the ASN GW/FA with an
MN address of 0.0.0.0.
9
The ASN GW/FA forwards a Proxy Mobile IP Registration Request message to the HA. The message includes fields such
as a Home Address indicator of 0.0.0.0, the IP address of the FA (the care-of-address), the IP address of the FA (the careof-address), and the FA-HA extension (security parameter index (SPI)).
10
While the FA is communicating with the HA, the MN may send additional IPCP Configuration Request messages.
11
The HA responds with a Proxy Mobile IP Registration Response. The response includes an IP address from one of its
locally configured pools to assign to the MN (its Home Address). The HA also creates a mobile binding record (MBR) for
the subscriber session.
12
The MN and the ASN GW/FA negotiate IPCP. The result is that the MN is assigned the home address originally specified
by the AAA server.
13
While the MN and ASN GW/FA are negotiating IPCP, the HA and AAA server initiate accounting.
14
Upon completion of the IPCP negotiation, the ASN GW/FA and AAA server initiate accounting fully establishing the
session allowing the MN to send/receive data to/from the PDN.
15
Upon completion of the session, the MN sends an LCP Terminate Request message to the ASN GW to end the subscriber
session.
16
The ASN GW/FA sends a Proxy Mobile IP De-registration Request message to the HA.
17
The ASN GW/FA send an LCP Terminate Acknowledge message to the MN ending the PPP session.
18
The HA sends a Proxy Mobile IP De-Registration Response message to the FA terminating the R3 interface
19
The ASN GW/FA and the BS terminate the R6 session.
20
The HA and the AAA server stop accounting for the session.
21
The ASN GW and the AAA server stop accounting for the session.
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How Proxy Mobile IP Works in a WiFi Network with Multiple
Authentication
Proxy-Mobile IP was developed as a result of networks of Mobile Subscribers (MS) that are not capable of Mobile IP
operation. In this scenario a PDIF acts a mobile IP client and thus implements Proxy-MIP support.
Although not required or necessary in a Proxy-MIP network, this implementation uses a technique called Multiple
Authentication. In Multi-Auth arrangements, the device is authenticated first using HSS servers. Once the device is
authenticated, then the subscriber is authenticated over a RADIUS interface to AAA servers. This supports existing EVDO servers in the network.
The MS first tries to establish an IKEv2 session with the PDIF. The MS uses the EAP-AKA authentication method for
the initial device authentication using Diameter over SCTP over IPv6 to communicate with HSS servers. After the
initial Diameter EAP authentication, the MS continues with EAP MD5/GTC authentication.
After successful device authentication, PDIF then uses RADIUS to communicate with AAA servers for the subscriber
authentication. It is assumed that RADIUS AAA servers do not use EAP methods and hence RADIUS messages do not
contain any EAP attributes.
Assuming a successful RADIUS authentication, PDIF then sets up the IPSec Child SA tunnel using a Tunnel Inner
Address (TIA) for passing control traffic only. PDIF receives the MS address from the Home Agent, and passes it on to
the MS through the final AUTH response in the IKEv2 exchange.
When IPSec negotiation finishes, the PDIF assigns a home address to the MS and establishes a CHILD SA to pass data.
The initial TIA tunnel is torn down and the IP address returned to the address pool.The PDIF then generates a RADIUS
accounting START message.
When the session is disconnected, the PDIF generates a RADIUS accounting STOP message.
The following figures describe a Proxy-MIP session setup using CHAP authentication (EAP-MD5), but also addresses a
PAP authentication setup using EAP-GTC when EAP-MD5 is not supported by either PDIF or MS.
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Figure 65.
Proxy-MIP Call Setup using CHAP Authentication
Table 34. Proxy-MIP Call Setup using CHAP Authentication
Step
Description
1
On connecting to WiFi network, MS first send DNS query to get PDIF IP address
2
MS receives PDIF address from DNS
3
MS sets up IKEv2/IPSec tunnel by sending IKE_SA_INIT Request to PDIF. MS includes SA, KE, Ni, NATDETECTION Notify payloads in the IKEv2 exchange.
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Step
Description
4
PDIF processes the IKE_SA_INIT Request for the appropriate PDIF service (bound by the destination IP address in the
IKEv2 INIT request). PDIF responds with IKE_SA_INIT Response with SA, KE, Nr payloads and NAT-Detection Notify
payloads. If multiple-authentication support is configured to be enabled in the PDIF service, PDIF will include
MULTIPLE_AUTH_SUPPORTED Notify payload in the IKE_SA_INIT Response. PDIF will start the IKEv2 setup timer
after sending the IKE_SA_INIT Response.
5
On receiving successful IKE_SA_INIT Response from PDIF, MS sends IKE_ AUTH Request for the first EAP-AKA
authentication. If the MS is capable of doing multiple-authentication, it will include MULTI_AUTH_SUPPORTED
Notify payload in the IKE_AUTH Request. MS also includes IDi payload which contains the NAI, SA, TSi, TSr, CP
(requesting IP address and DNS address) payloads. MS will not include AUTH payload to indicate that it will use EAP
methods.
6
On receiving IKE_AUTH Request from MS, PDIF sends DER message to Diameter AAA server. AAA servers are
selected based on domain profile, default subscriber template or default domain configurations. PDIF includes Multiple Auth-Support AVP, EAP-Payload AVP with EAP-Response/Identity in the DER. Exact details are explained in the
Diameter message sections. PDIF starts the session setup timer on receiving IKE_AUTH Request from MS.
7
PDIF receives DEA with Result-Code AVP specifying to continue EAP authentication. PDIF takes EAP-Payload AVP
contents and sends IKE_ AUTH Response back to MS in the EAP payload. PDIF allows IDr and CERT configurations in
the PDIF service and optionally includes IDr and CERT payloads (depending upon the configuration). PDIF optionally
includes AUTH payload in IKE_AUTH Response if PDIF service is configured to do so.
8
MS receives the IKE_AUTH Response from PDIF. MS processes the exchange and sends a new IKE_AUTH Request
with EAP payload. PDIF receives the new IKE_AUTH Request from MS and sends DER to AAA server. This DER
message contains the EAP-Payload AVP with EAP-AKA challenge response and challenge received from MS.
9
The AAA server sends the DEA back to the PDIF with Result-Code AVP as “success.” The EAP-Payload AVP message
also contains the EAP result code with “success.” The DEA also contains the IMSI for the user, which is included in the
Callback-Id AVP. PDIF uses this IMSI for all subsequent session management functions such as duplicate session
detection etc. PDIF also receives the MSK from AAA, which is used for further key computation.
10
PDIF sends the IKE_AUTH Response back to MS with the EAP payload.
11
MS sends the final IKE_AUTH Request for the first authentication with the AUTH p ayload computed from the keys. If
the MS plans to do the second authentication, it will include ANOTHER_AUTH_FOLLOWS Notify payload also.
12
PDIF processes the AUTH request and responds with the IKE_AUTH Response with the AUTH payload computed from
the MSK. PDIF does not assign any IP address for the MS pending second authentication. Nor will the PDIF include any
configuration payloads.
a. If PDIF service does not support Multiple-Authentication and ANOTHER_AUTH_FOLLOWS Notify payload is
received, then PDIF sends IKE_AUTH Response with appropriate error and terminate the IKEv2 session by sending
INFORMATIONAL (Delete) Request.b. If ANOTHER_AUTH_FOLLOWS Notify payload is not present in the
IKE_AUTH Request, PDIF allocates the IP address from the locally configured pools. However, if proxy-miprequired is enabled, then PDIF initiates Proxy-MIP setup to HA by sending P-MIP RRQ. When PDIF receives the
Proxy-MIP RRP, it takes the Home Address (and DNS addresses if any) and sends the IKE_AUTH Response back to MS
by including CP payload with Home Address and DNS addresses. In either case, IKEv2 setup will finish at this stage and
IPSec tunnel gets established with a Tunnel Inner Address (TIA).
13
MS does the second authentication by sending the IKE_AUTH Request with IDi payload to include the NAI. This NAI
may be completely different from the NAI used in the first authentication.
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Step
Description
14
On receiving the second authentication IKE_AUTH Request, PDIF checks the configured second authentication methods.
The second authentication may be either EAP-MD5 (default) or EAP-GTC. The EAP methods may be either EAPPassthru or EAP-Terminated.
a. If the configured method is EAP-MD5, PDIF sends the IKE_AUTH Response with EAP payload including
challenge.b. If the configured method is EAP-GTC, PDIF sends the IKE_AUTH Response with EAP-GTC.c. MS
processes the IKE_AUTH Response:
 If the MS supports EAP-MD5, and the received method is EAP-MD5, then the MS will take the challenge,
compute the response and send IKE_AUTH Request with EAP payload including Challenge and Response.

If the MS does not support EAP-MD5, but EAP-GTC, and the received method is EAP-MD5, the MS sends
legacy-Nak with EAP-GTC.
15(a) PDIF receives the new IKE_AUTH Request from MS.
If the original method was EAP-MD5 and MD5 challenge and response is received, PDIF sends RADIUS Access Request
with corresponding attributes (Challenge, Challenge Response, NAI, IMSI etc.).
15(b) If the original method was EAP-MD5 and legacy-Nak was received with GTC, the PDIF sends IKE_AUTH Response
with EAP-GTC.
16
PDIF receives Access Accept from RADIUS and sends IKE_AUTH Response with EAP success.
17
PDIF receives the final IKE_AUTH Request with AUTH payload.
18
PDIF checks the validity of the AUTH payload and initiates Proxy-MIP setup request to the Home Agent if proxy-miprequired is enabled. The HA address may be received from the RADIUS server in the Access Accept (Step 16) or may
be locally configured. PDIF may also remember the HA address from the first authentication received in the final DEA
message.
19
If proxy-mip-required is disabled, PDIF assigns the IP address from the local pool.
20
PDIF received proxy-MIP RRP and gets the IP address and DNS addresses.
21
PDIF sets up the IPSec tunnel with the home address. On receiving the IKE_AUTH Response MS also sets up the IPSec
tunnel using the received IP address. PDIF sends the IKE_AUTH Response back to MS by including the CP payload with
the IP address and optionally the DNS addresses. This completes the setup.
22
PDIF sends a RADIUS Accounting start message.
Important: For Proxy-MIP call setup using PAP, the first 14 steps are the same as for CHAP authentication.
However, here they deviate because the MS does not support EAP-MD5 authentication, but EAP-GTC. In response to
the EAP-MD5 challenge, the MS instead responds with legacy-Nak with EAP-GTC. The diagram below picks up at this
point.
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Figure 66.
Proxy-MIP Call Setup using PAP Authentication
Table 35. Proxy-MIP Call Setup using PAP Authentication
Step
Description
15
MS is not capable of CHAP authentication but PAP authentication, and the MS returns the EAP payload to indicate that it
needs EAP-GTC authentication.
16
PDIF then initiates EAP-GTC procedure, and requests a password from MS.
17
MS includes an authentication password in the EAP payload to PDIF.
18
Upon receipt of the password, PDIF sends a RADIUS Access Request which includes NAI in the User-Name attribute and
PAP-password.
19
Upon successful authentication, the AAA server returns a RADIUS Access Accept message, which may include FramedIP-Address attribute.
20
The attribute content in the Access Accept message is encoded as EAP payload with EAP success when PDIF sends the
IKE_AUTH Response to the MS.
21
The MS and PDIF now have a secure IPSec tunnel for communication.
22
Pdif sends an Accounting START message.
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Configuring Proxy Mobile-IP Support
Support for Proxy Mobile-IP requires that the following configurations be made:
Important: Not all commands and keywords/variables may be supported. This depends on the platform type and
the installed license(s).
 FA service(s): Proxy Mobile IP must be enabled, operation parameters must be configured, and FA-HA security
associations must be specified.
 HA service(s): FA-HA security associations must be specified.
 Subscriber profile(s): Attributes must be configured to allow the subscriber(s) to use Proxy Mobile IP. These
attributes can be configured in subscriber profiles stored locally on the system or remotely on a RADIUS AAA
server.
 APN template(s): Proxy Mobile IP can be supported for every subscriber IP PDP context facilitated by a
specific APN template based on the configuration of the APN.
Important: These instructions assume that the system was previously configured to support
subscriber data sessions as a core network service and/or an HA according to the instructions
described in the respective product administration guide.
Configuring FA Services
Use this example to configure an FA service to support Proxy Mobile IP:
configure
context <context_name>
fa-service <fa_service_name>
proxy-mip allow
proxy-mip max-retransmissions <integer>
proxy-mip retransmission-timeout <seconds>
proxy-mip renew-percent-time percentage
fa-ha-spi remote-address { ha_ip_address | ip_addr_mask_combo } spi-number
number { encrypted secret enc_secret | secret secret } [ description string ][ hashalgorithm { hmac-md5 | md5 | rfc2002-md5 } | replay-protection { timestamp | nonce } |
timestamp-tolerance tolerance ]
authentication mn-ha allow-noauth
end
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Notes:
 The proxy-mip max-retransmissions command configures the maximum number re-try attempts that the
FA service is allowed to make when sending Proxy Mobile IP Registration Requests to the HA.
 proxy-mip retransmission-timeout configures the maximum amount of time allowed by the FA for a
response from the HA before re-sending a Proxy Mobile IP Registration Request message.
 proxy-mip renew-percent-time configures the amount of time that must pass prior to the FA sending a
Proxy Mobile IP Registration Renewal Request.
Example
If the advertisement registration lifetime configured for the FA service is 900 seconds and the renew-time is
configured to 50%, then the FA requests a lifetime of 900 seconds in the Proxy MIP registration request. If
the HA grants a lifetime of 600 seconds, then the FA sends the Proxy Mobile IP Registration Renewal
Request message after 300 seconds have passed.
 Use the fa-ha-spi remote-address command to modify configured FA-HA SPIs to support Proxy Mobile
IP. Refer to the Command Line Interface Reference for the full command syntax.
Important: Note that FA-HA SPIs must be configured for the Proxy-MIP feature to work,
while it is optional for regular MIP.
 Use the authentication mn-ha allow-noauth command to configure the FA service to allow
communications from the HA without authenticating the HA.
Verify the FA Service Configuration
Use the following command to verify the configuration of the FA service:
show fa-service name <fa_service_name>
Notes:
 Repeat this example as needed to configure additional FA services to support Proxy-MIP.
 Save your configuration to flash memory, an external memory device, and/or a network location using the Exec
mode command save configuration . For additional information on how to verify and save configuration
files, refer to the System Administration Guide and the Command Line Interface Reference.
Proceed to the optional Configuring Proxy MIP HA Failover section to configure Proxy MIP HA Failover support or
skip to the Configuring HA Services section to configure HA service support for Proxy Mobile IP.
Configuring Proxy MIP HA Failover
Use this example to configure Proxy Mobile IP HA Failover:
Important: This configuration in this section is optional.
When configured, Proxy MIP HA Failover provides a mechanism to use a specified alternate Home Agent for the
subscriber session when the primary HA is not available. Use the following configuration example to configure the
Proxy MIP HA Failover:
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configure
context <context_name>
fa-service <fa_service_name>
proxy-mip ha-failover [ max-attempts <max_attempts> | num-attemptsbefore-switching <num_attempts> | timeout <seconds> ]
Notes:
 Save your configuration to flash memory, an external memory device, and/or a network location using the Exec
mode command save configuration . For additional information on how to verify and save configuration
files, refer to the System Administration Guide and the Command Line Interface Reference.
Configuring HA Services
Use the following configuration example to configure HA services to support Proxy Mobile IP.
configure
context <context_name>
ha-service <ha_service_name>
Important: Note that FA-HA SPIs must be configured for the Proxy MIP feature to work while it is optional for
regular MIP. Also note that the above syntax assumes that FA-HA SPIs were previously configured as part of the HA
service as described in respective product Administration Guide. The replay-protection and timestamptolerance keywords should only be configured when supporting Proxy Mobile IP.
fa-ha-spi remote-address <fa_ip_address> spi-number <number> { encrypted secret
<enc_secret> | secret <secret> } [ description <string> ] [ hash-algorithm { hmac-md5 |
md5 | rfc2002-md5 } ] replay-protection { timestamp | nonce } | timestamp-tolerance
<tolerance> ]
authentication mn-ha allow-noauth
authentication mn-aaa allow-noauth
end
Notes:
 Repeat this example as needed to configure additional HA services to support Proxy-MIP.
 Save your configuration to flash memory, an external memory device, and/or a network location using the Exec
mode command save configuration . For additional information on how to verify and save configuration
files, refer to the System Administration Guide and the Command Line Interface Reference.
To verify the configuration of the HA service:
context <context_name>
show ha-service name <ha_service_name>
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Configuring Subscriber Profile RADIUS Attributes
In order for subscribers to use Proxy Mobile IP, attributes must be configured in their user profile or in an APN for
3GPP service. As mentioned previously, the subscriber profiles can be located either locally on the system or remotely
on a RADIUS AAA server.
This section provides information on the RADIUS attributes that must be used and instructions for configuring locally
stored profiles/APNs in support of Proxy Mobile IP.
Important: Instructions for configuring RADIUS-based subscriber profiles are not provided in this document.
Please refer to the documentation supplied with your server for further information.
RADIUS Attributes Required for Proxy Mobile IP
The following table describes the attributes that must be configured in profiles stored on RADIUS AAA servers in order
for the subscriber to use Proxy Mobile IP.
Table 36.
Required RADIUS Attributes for Proxy Mobile IP
Attribute
Description
SN-SubscriberPermission
OR
SN1-SubscriberPermission
Indicates the services allowed to be delivered to the subscriber.
For Proxy Mobile IP, this attribute must be set to Simple IP.
SN-Proxy-MIP
OR
SN1-Proxy-MIP
SN-SimultaneousSIP-MIP
OR
SN1SimultaneousSIP-MIP
Specifies if the configured service will perform compulsory Proxy-MIP
tunneling for a Simple-IP subscriber.
This attribute must be enabled to support Proxy Mobile IP.
Indicates whether or not a subscriber can simultaneously access both
Simple IP and Mobile IP services.
Important: Regardless of the configuration of this
attribute, the FA facilitating the Proxy Mobile IP session will
not allow simultaneous Simple IP and Mobile IP sessions for
the MN.
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Values

None (0)

Simple IP (0x01)

Mobile IP (0x02)

Home Agent
Terminated Mobile IP
(0x04)

Disabled - do not
perform compulsory
Proxy-MIP (0)

Enabled - perform
compulsory ProxyMIP (1)

Disabled (0)

Enabled (1)
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Attribute
Description
Values
SN-PDSNHandoff- Req-IPAddr
OR
SN1-PDSNHandoff- Req-IPAddr
Specifies whether or not the system should reject and terminate the
subscriber session when the proposed address in IPC