Extreme Control Center NS-A-20 Installation Guide

®
Extreme Control Center NSA-20 Installation Guide
9034971
Published April 2016
Copyright © 2016 All rights reserved.
Legal Notice
Extreme Networks, Inc. reserves the right to make changes in specifications and other information
contained in this document and its website without prior notice. The reader should in all cases
consult representatives of Extreme Networks to determine whether any such changes have been
made.
The hardware, firmware, software or any specifications described or referred to in this document
are subject to change without notice.
Trademarks
Extreme Networks and the Extreme Networks logo are trademarks or registered trademarks of
Extreme Networks, Inc. in the United States and/or other countries.
All other names (including any product names) mentioned in this document are the property of
their respective owners and may be trademarks or registered trademarks of their respective
companies/owners.
For additional information on Extreme Networks trademarks, please see:
www.extremenetworks.com/company/legal/trademarks/
Support
For product support, including documentation, visit: www.extremenetworks.com/documentation/
For information, contact:
Extreme Networks, Inc.
145 Rio Robles
San Jose, California 95134
USA
Table of Contents
About This Guide....................................................................................................................... 4
Text Conventions...................................................................................................................................................................4
Related Publications............................................................................................................................................................ 5
Getting Help.............................................................................................................................................................................5
Providing Feedback to Us................................................................................................................................................ 6
Chapter 1: Appliance Overview and Setup.............................................................................7
Kit Contents............................................................................................................................................................................. 7
Specifications.......................................................................................................................................................................... 7
Front Panel Features........................................................................................................................................................... 9
Back Panel Features...........................................................................................................................................................10
Removing and Installing the Front Bezel.................................................................................................................. 11
Installing the Appliance into a Rack........................................................................................................................... 12
Chapter 2: Configuration.........................................................................................................14
Pre-Configuration Tasks................................................................................................................................................... 14
Configuring the Appliance..............................................................................................................................................14
Launching Extreme Control Center Applications................................................................................................19
Restoring a Database from a Windows Server to the Appliance...............................................................20
Changing Appliance Settings........................................................................................................................................ 21
Upgrading Extreme Control Center Appliance Software............................................................................... 22
Chapter 3: Reinstalling Appliance Software........................................................................ 23
Appendix A: Glossary.............................................................................................................. 25
A..................................................................................................................................................................................................25
B.................................................................................................................................................................................................. 28
C..................................................................................................................................................................................................29
D................................................................................................................................................................................................. 34
E.................................................................................................................................................................................................. 37
F................................................................................................................................................................................................... 41
G................................................................................................................................................................................................. 43
H................................................................................................................................................................................................. 44
I....................................................................................................................................................................................................45
J.................................................................................................................................................................................................. 49
L.................................................................................................................................................................................................. 49
M...................................................................................................................................................................................................51
N..................................................................................................................................................................................................55
O................................................................................................................................................................................................. 56
P.................................................................................................................................................................................................. 58
Q.................................................................................................................................................................................................. 61
R..................................................................................................................................................................................................62
S.................................................................................................................................................................................................. 65
T.................................................................................................................................................................................................. 69
U................................................................................................................................................................................................... 71
V.................................................................................................................................................................................................. 72
W................................................................................................................................................................................................ 75
X..................................................................................................................................................................................................76
Extreme Control Center® NS-A-20 Installation Guide
3
About This Guide
This document describes the installation and initial configuration of the Extreme Networks Extreme
Control Center NS-A-20 hardware appliance.
This document is intended for experienced network administrators who are responsible for
implementing and maintaining communications networks.
Text Conventions
The following tables list text conventions that are used throughout this guide.
Table 1: Notice Icons
Icon
Notice Type
Alerts you to...
General Notice
Helpful tips and notices for using the product.
Note
Important features or instructions.
Caution
Risk of personal injury, system damage, or loss of data.
Warning
Risk of severe personal injury.
New
This command or section is new for this release.
Table 2: Text Conventions
Convention
Screen displays
Description
This typeface indicates command syntax, or represents information as it appears on the
screen.
The words enter and
type
When you see the word “enter” in this guide, you must type something, and then press
the Return or Enter key. Do not press the Return or Enter key when an instruction
simply says “type.”
[Key] names
Key names are written with brackets, such as [Return] or [Esc]. If you must press two
or more keys simultaneously, the key names are linked with a plus sign (+). Example:
Press [Ctrl]+[Alt]+[Del]
Words in italicized type
Italics emphasize a point or denote new terms at the place where they are defined in
the text. Italics are also used when referring to publication titles.
Extreme Control Center® NS-A-20 Installation Guide
4
About This Guide
Related Publications
Extreme Control Center® Documentation
Extreme Control Center (ECC, formerly NetSight) documentation, including release notes, are available
at: https://extranet.extremenetworks.com/. You must have a valid customer account to access this site.
Extreme Control Center online help is available from the Help menu in all ECC software applications.
The online help provides detailed explanations of how to configure and manage your network using
ECC software applications.
For complete regulatory compliance and safety information, refer to the document Intel® Server
Products Product Safety and Regulatory Compliance.
Other Documentation
•
•
•
ExtremeXOS Command Reference Guide
ExtremeXOS Release Notes
ExtremeXOS User Guide
Getting Help
If you require assistance, you can contact Extreme Networks using one of the following methods:
•
•
•
•
Global Technical Assistance Center (GTAC) for Immediate Support
• Phone: 1-800-872-8440 (toll-free in U.S. and Canada) or 1-603-952-5000. For the Extreme
Networks support phone number in your country, visit: www.extremenetworks.com/support/
contact
• Email: support@extremenetworks.com. To expedite your message, enter the product name or
model number in the subject line.
GTAC Knowledge — Get on-demand and tested resolutions from the GTAC Knowledgebase, or
create a help case if you need more guidance.
The Hub — A forum for Extreme customers to connect with one another, get questions answered,
share ideas and feedback, and get problems solved. This community is monitored by Extreme
Networks employees, but is not intended to replace specific guidance from GTAC.
Support Portal — Manage cases, downloads, service contracts, product licensing, and training and
certifications.
Before contacting Extreme Networks for technical support, have the following information ready:
•
•
•
•
•
Your Extreme Networks service contract number and/or serial numbers for all involved Extreme
Network products
A description of the failure
A description of any action(s) already taken to resolve the problem
A description of your network environment (such as layout, cable type, other relevant environmental
information)
Network load at the time of trouble (if known)
Extreme Control Center® NS-A-20 Installation Guide
5
About This Guide
•
•
The device history (for example, if you have returned the device before, or if this is a recurring
problem)
Any related Return Material Authorization (RMA) numbers
Providing Feedback to Us
We are always striving to improve our documentation and help you work better, so we want to hear
from you! We welcome all feedback but especially want to know about:
• Content errors or confusing or conflicting information.
• Ideas for improvements to our documentation so you can find the information you need faster.
• Broken links or usability issues.
If you would like to provide feedback to the Extreme Networks Information Development team about
this document, please contact us using our short online feedback form. You can also email us directly at
internalinfodev@extremenetworks.com.
Extreme Control Center® NS-A-20 Installation Guide
6
1 Appliance Overview and Setup
Kit Contents
Specifications
Front Panel Features
Back Panel Features
Removing and Installing the Front Bezel
Installing the Appliance into a Rack
This chapter lists the components shipped with the NS-A-20 appliance, describes the front and back
panels, and provides information on appliance specifications.
For complete regulatory compliance and safety information, refer to the document Intel® Server
Products Product Safety and Regulatory Compliance, available at the following links:
http://download.intel.com/support/motherboards/server/sb/g23122003_safetyregulatory.pdf
http://extranet.extremenetworks.com/downloads/pages/NMS.aspx
If you use the extranet URL, after entering your email address and password, you will be on the Extreme
Control Center page. Follow this path to the document:
Documentation > Manuals & Release Notes > select a version > Extreme Control Appliance.
Kit Contents
The NS-A-20 appliance ships with the following components:
•
•
•
•
•
•
Extreme Networks URL card
Front bezel label
A rack mounting kit
Two rack handles and appropriate screws
AC power cord bracket and cable clamp kit
One USB flash drive
Specifications
The physical specifications for the appliance are listed in the table below. The environmental
requirements are listed in Table 4: NS-A-20 Environmental Specifications on page 8.
Table 3: NS-A-20 Physical Specifications
Processor
Processor type
Dual Intel® Xeon® E5-2620 processors
Processor speed
2.0 GHz
Internal cache
15 MB per processor
Extreme Control Center® NS-A-20 Installation Guide
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Appliance Overview and Setup
Table 3: NS-A-20 Physical Specifications (continued)
System bus speed
7.20 GT/s (Gigatransfers per second)
System bus type
QPI (Quick Path Interconnect)
Memory
Architecture
1333MHz Dual Ranked Registered (RDIMM) ECC DDR3
Memory module sockets
Twenty-four 240-pin
Memory module capacities
2 GB RDIMMs
Minimum RAM (included)
24 GB (six 4 GB RDIMMs)
Maximum RAM
48 GB (twenty-four 2 GB RDIMMs)
Drives
Hard drives
Two 1 TB 7200 RPM hard drives configured at RAID 1
Connectors
Back
NIC
Four RJ-45
Serial
9-pin, DTE, 16550-compatible
USB
Three 4-pin, USB 2.0-compliant
Video
15-pin VGA
Front
USB
Two 4-pin, USB 2.0-compliant
Power
AC power supply (per power supply)
Redundant power supply
Wattage
750 watts
Input voltage
100 – 127 V at 50/60 Hz 8.2 A
200 – 240 V at 50/60 Hz 4.4 A
Output voltage
62.0A at 12 V
2.1A at 12 VSB
Physical
Height
4.45 cm (1.75 in.)
Width
43.0 cm (16.93 in.)
Depth
70.99 cm (27.95 in.)
Weight (maximum configuration)
26.1 kg (57.54 lb.)
Table 4: NS-A-20 Environmental Specifications
Parameter
Limits
Operating temperature
+10°C to +35°C with the maximum rate of change not to exceed
10°C per hour
Storage temperature
-40°C to +70°C
Extreme Control Center® NS-A-20 Installation Guide
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Appliance Overview and Setup
Table 4: NS-A-20 Environmental Specifications (continued)
Parameter
Limits
Storage humidity
90%, non-condensing at 35°C
Vibration, unpackaged
5 Hz to 500 Hz, 2.20 g RMS random
Shock, operating
Half sine, 2 g peak, 11 milliseconds
Shock, unpackaged
Trapezoidal, 25 g, velocity change 136 inches/second (40 lbs to <
80 lbs)
Shock, packaged
Non-palletized free fall in height 24 inches (40 lbs to < 80 lbs)
ESD
+/-12 KV except I/O port +/- 8 KV per Intel® Environmental test
specification
Estimated thermal dissipation
1550 BTU/Hr
Front Panel Features
The following figure shows the NS-A-20 appliance front panel features. Figure 2: Front Control Panel on
page 9 shows the front control panel.
Figure 1: NS-A-20 Front Panel Features
A
System label pull-out
C
Front control panel (see Figure 2: Front Control
Panel on page 9)
B
USB 2.0 ports
D
Hard disk drive bays
Figure 2: Front Control Panel
A
System ID button w/integrated LED
F
System status LED
B
NMI button (recessed, tool required for use)
G
Power button w/integrated LED
C
Mgmt port activity LED
H
Hard drive activity LED
Extreme Control Center® NS-A-20 Installation Guide
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Appliance Overview and Setup
D
Not used
I
Not used
E
System cold reset button
J
Not used
Hard Drive LED Indicator Patterns
The hard drive has two LED indicators visible from the front of the system: one is a green LED for disk
activity, and the other is amber and indicates hard drive status. The LEDs have the following states, as
described in the tables below.
Table 5: Hard Drive Activity LED Indicator Patterns
Hard Drive Condition
Activity LED Patterns
Power on and drive spinning up or spinning down
Off
Power on with drive activity
Blinking green
Table 6: Hard Drive Status LED Indicator Patterns
Hard Drive Condition
Status LED Patterns
No access or no fault
Off
Hard drive fault has occurred
Solid amber
Back Panel Features
The figure below shows the NS-A-20 appliance back panel.
Figure 3: NS-A-20 Back Panel
A
Power supply module #1
G
Video connector
B
Power supply module #2
H
Not used
C
eth0, Mgmt Port, 1 GbE RJ45
I
USB 2.0 ports
D
eth1
J
Not used
E
eth2
K
Not used
F
eth3
L
Not used
The following table describes the LEDs for the RJ45 management port.
Extreme Control Center® NS-A-20 Installation Guide
10
Appliance Overview and Setup
Table 7: RJ45 Port LEDs (Management Port)
LED Type
LED Pattern
Status Indication
Network speed (right)
Off
10 Mbps
Amber
100 Mbps
Green
1000 Mbps
Off
No link
Solid Green
Active link
Blinking Green
Data traffic activity
Link activity (left)
Power Supply Status Indicator Patterns
The appliance has two power supplies, supplying hot-pluggable power redundancy. The system
distributes the power load across both power supplies to maximize efficiency.
Each power supply has a single bi-color LED to indicate power supply status, as described in the table
below.
Table 8: Power Supply Status LED Indicator Patterns
Power Supply Condition
LED Pattern
Output on and OK
Green
No AC power to all power supplies
Off
AC present / Only 12VSB on (PS off) or PS in cold redundant state
1Hz blinking green
AC power cord unplugged or AC power lost. With a 2nd PS in parallel still with AC input
power
Amber
Power supply warning events where PS continues to operate — high temp, high power,
high current, slow fan
1Hz blinking amber
Power supply critical event causing a shutdown, failure, OCP, OVP, fan fail
Amber
Power supply firmware updating
2Hz blinking green
Removing and Installing the Front Bezel
The NS-A-20 appliance comes with an optional front panel bezel that can be attached to the front of
the chassis by snapping the bezel onto the chassis handles. A key lock allows you to lock the bezel in
place so that front panel controls cannot be used. You can still monitor system status indicators with the
bezel in place.
Removing the Front Bezel
To remove the front bezel:
1
Unlock the bezel if it is locked.
Extreme Control Center® NS-A-20 Installation Guide
11
Appliance Overview and Setup
2 Remove the left end of the front bezel from rack handle.
3 Rotate the front bezel counterclockwise to release the latches on the right end from the rack handle.
Installing the Front Bezel
Note
Before installing the bezel, you must install the rack handles. See Installing the Appliance into
a Rack on page 12.
To install the front bezel:
1 Lock the right end of the front bezel to the rack handle.
2 Rotate the front bezel clockwise till the left end clicks into place.
3 Lock the bezel, if needed.
Installing the Appliance into a Rack
A rack mounting kit and installation guide are included with the NS-A-20 appliance. The rack mounting
kit allows you to install the appliance into a four-post rack cabinet. Refer to the installation guide for
complete installation instructions.
If you are table mounting the appliance, ensure at least 6 cm of clearance on all sides of the appliance
for proper ventilation.
If you are installing the appliance in a rack:
1
Install the rack handles by aligning a rack handle with the two holes on each side of the appliance
and attaching each handle to the appliance with two screws as shown in the figure below.
Figure 4: Installing the Rack Handles
2 Read the installation guide included with the rack mounting kit.
3 Install the rails and mount the controller in the rack as instructed.
Torque Values
The table below describes the recommended torque values to use when installing the appliance using
standard threaded fastener machine screws and bolts.
Extreme Control Center® NS-A-20 Installation Guide
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Appliance Overview and Setup
Table 9: Recommended Torque Values by Screw Size
Screw Size
Torque in Pounds
Bit Size
English
Metric
-%5
Nominal
+%5
N/A
N/A
1.42
1.5
1.57
0
2 – 56
1.5
2.85
3.0
3.15
0
4 – 40
2.5
4.75
5.0
5.25
0/1
6 – 32
3.5
8.55
9.0
9.45
1
8 – 32
4.5
17.10
18.0
18.90
2
10 – 32
5
30.40
32.0
33.60
2
1/4 – 20
6.5
63.65
67.0
70.35
3
Extreme Control Center® NS-A-20 Installation Guide
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2 Configuration
Pre-Configuration Tasks
Configuring the Appliance
Launching Extreme Control Center Applications
Restoring a Database from a Windows Server to the Appliance
Changing Appliance Settings
Upgrading Extreme Control Center Appliance Software
Once you have installed the appliance into a rack, you need to connect a monitor and a USB keyboard,
connect the power cord and network cable, and power it on (see Figure 1: NS-A-20 Front Panel Features
on page 9 and Figure 3: NS-A-20 Back Panel on page 10).
After the appliance boots and the appliance installation is complete, you must go through the initial
configuration process described in this chapter.
This chapter also includes information on how to change your appliance settings following your initial
configuration and how to upgrade the Extreme Control Center application software. For information on
reinstalling the Extreme Control Center appliance software, see Reinstalling Appliance Software on
page 23.
Pre-Configuration Tasks
Ensure that you have the following information prior to executing the configuration steps in the next
section:
•
•
•
•
•
Appliance hostname, IP address, and netmask
Default gateway IP address
Name server IP address and domain name
NIS (Network Information Services) server IP address
Network Time Protocol (NTP) server IP address
In addition, you will need to obtain the appropriate Extreme Control Center software license prior to
launching the Extreme Control Center applications. You will be prompted to enter a license when you
launch the application. (When you purchased Extreme Control Center, you received a Licensed Product
Entitlement ID. This Entitlement ID allows you to generate a product license. Refer to the instructions
included with the Entitlement ID that was sent to you.)
Configuring the Appliance
After the initial appliance installation is complete, use the following steps to configure the appliance to
run the Extreme Control Center appliance software:
Extreme Control Center® NS-A-20 Installation Guide
14
Configuration
1
Login as root with no password, and press [Enter].
The following screen appears:
=================================================================
Extreme Networks - Extreme Control Center Suite Appliance
Welcome to the Extreme Control Center Appliance Setup
=================================================================
Please enter the information as it is requested to continue with the
configuration. Typically a default value is displayed in brackets.
Pressing the [enter] key without entering a new value will use the
bracketed value and proceed to the next item.
If a default value cannot be provided, the prompt will indicate that
the item is either (Required) or (Optional). The [enter] key may be
pressed without entering data for (Optional) items. A value must be
entered for (Required) items.
At the end of the setup process, the existing settings will be
displayed and opportunity will be provided to correct any errors.
=================================================================
Press [enter] to begin setup or CTRL-C to exit:
2 Press [Enter] to begin the setup. The Root Password Configuration screen appears:
=================================================================
Root Password Configuration
=================================================================
There is currently no password set in the system administrator
account (root). It is recommended that you set one that is
active the first time the machine is rebooted.
=================================================================
Would you like to set a root password (y/n) [y]?
Note
You must set a new root password. This new root password will be used by the initial user
when logging in to the Extreme Control Center applications.
3 Press [Enter] to set a new root password. Enter the new password as prompted.
Enter new UNIX password:
Retype new UNIX password:
Password updated successfully.
4 After you create the new root password, a screen appears where you can specify a user other than
root to run the Extreme Control Center server, if desired. This user becomes the admin user for the
server.
=================================================================
Select the user to run the server as
=================================================================
Do you want to use an existing user? (y/n) [y]
Extreme Control Center® NS-A-20 Installation Guide
15
Configuration
5 Enter y to use an existing user if you already have a user defined on the machine and enter the user
name. Leave the name set to root if you do not want to specify another user. Accept your selection.
Enter n to create a new "netsight" user (netsight is the user name) and enter the password for this
new user. Re-enter the password and then accept your selection.
6 In the Extreme Control Suite Appliance Network Configuration screen, enter the requested
configuration information and press [Enter].
If you plan to use DNS, enter the IP address of the name server. If you are using a name server, you
must enter a domain name for the appliance. If you are using an NIS server to authenticate users
logging into the appliance, make sure the NIS domain name is valid or users may not be able to log
in to the Extreme Control Center applications.
=================================================================
Extreme Control Center Suite Appliance Network Configuration
=================================================================
Enter
Enter
Enter
Enter
Enter
Enter
the
the
the
the
the
the
hostname for the appliance (Required):
IP address for <hostname> [192.168.1.10]:
IP netmask [255.255.255.0]:
gateway address [192.168.1.1]:
IP address of the name server (Optional):
domain name for <hostname> (Optional):
Do you want to use NIS (y/n) [n]? y
Enter the IP address of the NIS server:
Enter the NIS domain name (Required):
7 In the Confirm Network Settings screen, you can accept the current configuration or modify the
settings.
=================================================================
Confirm Network Settings
=================================================================
These are the settings you have entered. Enter 0 or any key other
than a valid selection to continue.If you need to make a change,
enter the appropriate number now or run the /usr/postinstall/
dnetconfig script at a later time.
=================================================================
0. Accept settings and continue
1. Hostname:
<hostname>
2. IP address:
192.168.1.10
3. Netmask:
255.255.255.0
4. Gateway:
192.168.1.1
5. Nameserver:
6. Domain name: <domain name>
7. NIS Server/Domain:
Enter selection [0]:
Extreme Control Center® NS-A-20 Installation Guide
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Configuration
8 In the SNMP Configuration screen, enter the requested information for each line and press [Enter].
=================================================================
SNMP Configuration
=================================================================
The following information will be used to configure SNMP management
of this device. The SNMP information entered here must be used to
contact this device with remote management applications such as
Extreme Control Center Console.
=================================================================
Please enter the SNMP user name [snmpuser]:
Please enter the SNMP authentication credential [snmpauthcred]:
Please enter the SNMP privacy credential [snmpprivcred]:
9 In the Configure Date and Time Settings screen, select whether you want to use an external Network
Time Protocol (NTP) server. Enter y to use NTP, and enter your NTP server IP address(es). Enter n to
configure the date and time manually and proceed to step 11 on page 18.
=================================================================
Configure Date And Time Settings
=================================================================
The appliance date and time can be set manually or using an external
Network Time Protocol (NTP) server. It is strongly recommended that
NTP is used to configure the date and time to ensure accuracy of time
values for SNMP communications and logged events. Up to 5 server IP
addresses may be entered if NTP is used.
=================================================================
Do you want to use NTP (y/n) [y]? y
Please enter a NTP Server IP Address (Required): 144.131.10.120
Would you like to add another server (y/n) [n]? y
Please enter a NTP Server IP Address (Required): 144.131.10.121
Would you like to add another server (y/n) [n]? n
10 In the NTP Servers validate selection screen, enter 0 to accept the current settings and proceed to
the Set Time Zone screen at step 13 on page 18.
=================================================================
NTP Servers
=================================================================
These are the currently specified NTP servers. Enter 0 or any key
other than a valid selection to complete NTP configuration and
continue.
If you need to make a change, enter the appropriate number from the
choices listed below.
144.131.10.120
144.131.10.121
0. Accept the current settings
1. Restart NTP server selection
2. Set date and time manually
=================================================================
Enter selection [0]: 0
Extreme Control Center® NS-A-20 Installation Guide
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Configuration
11 If you answered no to using an NTP server to set date and time, set the date and time in the Set Date
and Time screen.
=================================================================
Set Date And Time
=================================================================
The current system date and time is:
Thu Oct 28 09:34:08 2013
Please enter the values for date and time as directed where input is
expected in the following format:
MM
- 2 digit month of year
DD
- 2 digit day of month
YYYY - 4 digit year
hh
- 2 digit hour of day using a 24 hour clock
mm
- 2 digit minute of hour
ss
- 2 digit seconds
=================================================================
Please enter the month [10]:
Please enter the day of the month [28]:
Please enter the year [2013]:
Please enter the hour of day [09]:
Please enter the minutes [34]:
Please enter the seconds [08]:
12 In the Use UTC screen, select whether you want the system clock to be set to use UTC.
=================================================================
Use UTC
=================================================================
The system clock can be set to use UTC. Specifying no for using UTC,
sets the hardware clock using localtime.
=================================================================
Do you want to use UTC (y/n) [n]?
13 In the Set Time Zone screen, select the appropriate time zone and press [Enter].
=================================================================
Set Time Zone
=================================================================
You will now be asked to enter the time zone information for this
system. Available time zones are stored in files in the /usr/share/
zoneinfo directory. Please select from one of the following example
time zones:
1. US Eastern
2. US Central
3. US Mountain
4. US Pacific
5. Other - Shows a graphical list
=================================================================
Enter selection [1]:
Extreme Control Center® NS-A-20 Installation Guide
18
Configuration
14 The Modify Settings screen summarizes the settings you have entered and provides an opportunity
to modify the settings, if desired. Enter 0 to accept the settings.
================================================================
Modify Settings
=================================================================
All of the information needed to complete the installation of the
Extreme Control Center Appliance has been entered. Enter 0 or any key
other than a valid selection to continue. If you need to make a
change, enter the appropriate number from the choices listed below.
=================================================================
0. Accept settings and continue
1. Set the root user password
2. Set user to run server as
3. Set hostname and network settings
4. Set SNMP settings
5. Set the system time
6. Modify all settings
Enter selection [0]:
The Extreme Control Center appliance software is automatically installed. This could take a few minutes.
When the installation is complete, you’ll see the following screen.
=================================================================
Extreme Networks - Extreme Control Center Suite Appliance - Setup
Complete
=================================================================
Setup of the Extreme Control Center Appliance is now complete. The
appliance is now operational and ready to accept remote connections.
Details of the installation are located in the /var/log/install
directory.
=================================================================
Launching Extreme Control Center Applications
Now that you have configured the Extreme Control Center appliance, you are ready to access the
Extreme Control Center Launch Page and run the applications from a remote client machine.
Extreme Control Center® NS-A-20 Installation Guide
19
Configuration
1
Open a browser window on the remote client machine and enter the Extreme Control Center Launch
page URL in the following format:
http://<servername>:8080/
where <servername> is the Extreme Control Center appliance IP address or hostname, and 8080
is the required port number. For example,
http://10.20.30.40:8080/
The Extreme Control Center Launch Page opens.
2 Launch your Extreme Control Center applications by clicking on the names or icons of any of the
listed applications.
A login window appears.
3 Log in as root with the same password you defined in step 3 on page 15 or as the user you specified
in step 4 on page 15.
This is because the Extreme Control Center Server has a single pre-defined user that is the user who
performed the installation. Once the initial user has logged in, additional users can be defined.
The first time you attempt to launch an Extreme Control Center application, you will be prompted for
the license text you received when you generated your Extreme Control Center product license.
For more information on the Extreme Control Center Launch page, access the Online Help by clicking
on Help in the right corner of the Launch Page banner. In the Online Help Table of Contents, select
Installation Guide and then read the section titled "Remote Client Launch."
Restoring a Database from a Windows Server to the Appliance
This section describes several Extreme Control Center configuration changes that are required if you are
moving your Extreme Control Center installation from a Windows platform system to the appliance. The
steps are performed after restoring your database to the new appliance. (For information on restoring a
database, see the Server Information section in the Extreme Control Center Suite-Wide Tools User
Guide.)
Changing Console
Use the following instructions to change the location of syslog and trap information to the new location
on the appliance.
Changing Syslog Location
Change the Syslog Log Manager to point to the new location on the appliance. This will allow the
display of syslog information in the Syslog Event View tab.
1
From the Console menu bar, select Tools > Alarm/Event > Event View Manager.
2 Click on the Syslog entry under Available Log Managers, and click the Edit button.
The Log Manager Parameters window opens.
3 Change the path in the Log Directory field to /var/log/messages.
4 Change the Pattern to Red Hat LINUX Syslog Pattern.
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Configuration
5 Click OK.
Changing Traps Location
Change the Traps Log Manager to point to the new location on the appliance. This will allow the display
of trap information in the Traps Event View tab.
1 From the Console menu bar, select Tools > Alarm/Event > Event View Manager.
2 Click on the Traps entry under Available Log Managers, and click the Edit button.
The Log Manager Parameters window opens.
3 Change the path in the Log Directory field to %logdir%/traps.
4 Click OK.
Changing Inventory Manager
If you are using Inventory Manager, you must change the Data Storage Directory path to point to the
new location on the appliance. The Data Storage Directory is where all Inventory Manager data is stored,
including capacity planning reports, configuration templates, archived configurations, and property files.
1 From the Inventory Manager menu bar, select Tools > Options.
2 Expand the Inventory Manager options folder and select Data Storage Directory Path.
3 Change the path to the correct new location.
On a default Linux install, the path would be:
/usr/local/Extreme_Networks/NetSight/appdata/InventoryMgr/
4 Click OK.
Changing Appliance Settings
Use these steps if you need to change your Extreme Control Center appliance settings following your
initial appliance configuration.
Changing Basic Network Configuration
To change basic network configuration settings such as hostname and appliance IP address, enter the
following command at the appliance CLI:
/usr/postinstall/dnetconfig
This will start the network configuration script and allow you to make the required changes. You must
reboot the appliance for the new settings to take effect.
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Configuration
Changing SNMP Configuration
To change SNMP configuration settings such as system contact, system location, Trap Server, SNMP
Trap Community String, SNMP User, SNMP Authentication, and SNMP Privacy credentials, enter the
following command at the appliance CLI:
/usr/postinstall/snmpconfig
This will start the SNMP configuration script and allow you to make the required changes.
Changing Date and Time Settings
To enable or disable NTP for appliance date and time, or to manually set the date and time on the
appliance, enter the following command at the appliance CLI:
/usr/postinstall/dateconfig
This will start the date and time configuration script and allow you to change the settings.
Upgrading Extreme Control Center Appliance Software
Upgrades to the Extreme Control Center appliance software are available on the NMS web page.
1
On a system with an internet connection, go to the Extreme Control Center (NetSight) Downloads
web page to download the Appliance Image 64-bit upgrade file to your system: http://
extranet.extremenetworks.com/downloads/pages/NMS.aspx
2 Enter your email address and password.
3
4
5
6
7
You will be on the Extreme Control Center page.
Click on the Software tab and select a version of Extreme Control Center. Scroll down to see the
appliance images.
Use FTP, SCP, or a shared mount point, to copy the upgrade file to the Extreme Control Center
appliance.
SSH to the appliance.
Cd to the directory where you downloaded the upgrade file.
Change the permissions on the upgrade file by entering the following command:
chmod 755 NetSight_Suite_<version>_install.bin
8 Run the install program by entering the following command:
./NetSight_Suite_<version>_install.bin
The upgrade automatically begins.
The Extreme Control Center Server will be restarted automatically when the upgrade is complete.
Because your Extreme Control Center appliance settings were migrated, you are not required to
perform any configuration on the appliance following the upgrade.
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3 Reinstalling Appliance Software
Use the procedure in this chapter to reinstall the appliance software, in the event a software reinstall
becomes necessary. Be aware that this procedure reformats the hard drive and reinstalls all the
appliance software, the operating system, and all related Linux packages.
You will need to connect a monitor and a USB keyboard to the appliance prior to performing these
steps.
1
On a Windows platform system, go to the Extreme Control Center (NetSight) web page to
download the Appliance Image 64-bit file to your system: http://extranet.extremenetworks.com/
downloads/pages/NMS.aspx
After entering your email address and password, you will be on the Extreme Control Center page.
Click on the Software tab and select a version of Extreme Control Center. Scroll down to the
Appliance Image 64-bit (ZIP) file and extract the file to a directory on your system.
2 Insert the USB flash drive that came with the appliance into the USB port on your system and note
the drive letter it is assigned.
3 Open a command prompt window and cd to the directory where you extracted the file.
4 Type make_disk.bat <drive letter>:.
Note
Because the reinstall procedure reformats the drive, be sure you have specified the correct
drive letter.
5 Press [Enter].
The files will be copied to the USB flash drive. When the copy is complete you will see the message:
Successfully installed into <drive letter>: Press any key to continue.
6 Remove the USB flash drive from your system.
7 Insert the USB flash drive into a USB port on the appliance (see Figure 1: NS-A-20 Front Panel
Features on page 9).
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Reinstalling Appliance Software
8 Boot the appliance from the USB drive using either of these two methods.
•
Method 1:
1
2
3
4
•
Press the power button, and then press F6 to go to the Boot Menu.
Select the USB drive on the menu.
The appliance starts booting from the USB flash drive.
When the boot is complete, the Appliance Installation screen appears and the installation
begins.
Method 2:
1
2
3
4
5
6
Press the power button, and then press F2 to go to the BIOS setup.
Use the arrow keys to navigate to the Boot Options menu.
Ensure that the USB flash drive is listed as Boot Option #1 at the top.
Save changes and exit.
The appliance starts booting from the USB flash drive.
When the boot is complete, the Appliance Installation screen appears and the installation
begins.
9 After the installation completes, reboot the appliance and remove the USB flash drive.
10 Proceed to Configuration on page 14, and follow the instructions for configuring the appliance.
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A Glossary
A
B
C
D
E
F
G
H
I
J
L
M
N
O
P
Q
R
S
T
U
V
W
X
A
AAA
Authentication, authorization, and accounting. A system in IP-based networking to control which
computer resources specific users can access and to keep track of the activity of specific users over the
network.
ABR
Area border router. In OSPF, an ABR has interfaces in multiple areas, and it is responsible for exchanging
summary advertisements with other ABRs.
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Glossary
ACL
Access Control List. A mechanism for filtering packets at the hardware level. Packets can be classified
by characteristics such as the source or destination MAC, IP addresses, IP type, or QoS queue. Once
classified, the packets can be forwarded, counted, queued, or dropped.
ACMI
Asynchronous Chassis Management Interface.
ad-hoc mode
An 802.11 networking framework in which devices or stations communicate directly with each other,
without the use of an access point (AP).
AES
Advanced Encryption Standard. AES is an algorithm for encryption that works at multiple network
layers simultaneously. As a block cipher, AES encrypts data in fixed-size blocks of 128 bits; AES is also a
privacy transform for IPSec and Internet Key Exchange (IKE). Created by the National Institute of
Standards and Technology (NIST), the standard has a variable key length—it can specify a 128-bit key
(the default), a 192-bit key, or a 256-bit key.
For the WPA2/802.11i implementation of AES, a 128-bit key length is used. AES encryption includes four
stages that make up one round. Each round is then iterated 10, 12, or 14 times depending upon the bitkey size. For the WPA2/802.11i implementation of AES, each round is iterated 10 times.
AES-CCMP
Advanced Encryption Standard - Counter-Mode/CBC-MAC Protocol. CCM is a new mode of operation
for a block cipher that enables a single key to be used for both encryption and authentication. The two
underlying modes employed in CCM include Counter mode (CTR) that achieves data encryption and
Cipher Block Chaining Message Authentication Code (CBC-MAC) to provide data integrity.
alternate port
In RSTP, the alternate port supplies an alternate path to the root bridge and the root port.
AP (access point)
In wireless technology, access points are LAN transceivers or "base stations" that can connect to the
regular wired network and forward and receive the radio signals that transmit wireless data.
area
In OSPF, an area is a logical set of segments connected by routers. The topology within an area is
hidden from the rest of the autonomous system (AS).
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Glossary
ARP
Address Resolution Protocol. ARP is part of the TCP/IP suite used to dynamically associate a device's
physical address (MAC address) with its logical address (IP address). The system broadcasts an ARP
request, containing the IP address, and the device with that IP address sends back its MAC address so
that traffic can be transmitted.
AS
Autonomous system. In OSPF, an AS is a connected segment of a network topology that consists of a
collection of subnetworks (with hosts attached) interconnected by a set of routes. The subnetworks and
the routers are expected to be under the control of a single administration. Within an AS, routers may
use one or more interior routing protocols and sometimes several sets of metrics. An AS is expected to
present to other autonomous systems an appearance of a coherent interior routing plan and a
consistent picture of the destinations reachable through the AS. An AS is identified by a unique 16-bit
number.
ASBR
Autonomous system border router. In OSPF, an ASBR acts as a gateway between OSPF and other
routing protocols or other autonomous systems.
association
A connection between a wireless device and an access point.
asynchronous
See ATM.
ATM
Asynchronous transmission mode. A start/stop transmission in which each character is preceded by a
start signal and followed by one or more stop signals. A variable time interval can exist between
characters. ATM is the preferred technology for the transfer of images.
autobind
In STP, autobind (when enabled) automatically adds or removes ports from the STPD. If ports are
added to the carrier VLAN, the member ports of the VLAN are automatically added to the STPD. If
ports are removed from the carrier VLAN, those ports are also removed from the STPD.
autonegotiation
As set forth in IEEE 802.3u, autonegotation allows each port on the switch—in partnership with its link
partner—to select the highest speed between 10 Mbps and 100 Mbps and the best duplex mode.
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Glossary
B
backbone area
In OSPF, a network that has more than one area must have a backbone area, configured as 0.0.0.0. All
areas in an autonomous system (AS) must connect to the backbone area.
backup port
In RSTP, the backup port supports the designated port on the same attached LAN segment. Backup
ports exist only when the bridge is connected as a self-loop or to a shared media segment.
backup router
In VRRP, the backup router is any VRRP router in the VRRP virtual router that is not elected as the
master. The backup router is available to assume forwarding responsibility if the master becomes
unavailable.
BDR
Backup designated router. In OSPF, the system elects a designated router (DR) and a BDR. The BDR
smooths the transition to the DR, and each multi-access network has a BDR. The BDR is adjacent to all
routers on the network and becomes the DR when the previous DR fails. The period of disruption in
transit traffic lasts only as long as it takes to flood the new LSAs (which announce the new DR). The
BDR is elected by the protocol; each hello packet has a field that specifies the BDR for the network.
BGP
Border Gateway Protocol. BGP is a router protocol in the IP suite designed to exchange network
reachability information with BGP systems in other autonomous systems. You use a fully meshed
configuration with BGP.
BGP provides routing updates that include a network number, a list of ASs that the routing information
passed through, and a list of other path attributes. BGP works with cost metrics to choose the best
available path; it sends updated router information only when one host has detected a change, and only
the affected part of the routing table is sent.
BGP communicates within one AS using Interior BGP (IBGP) because BGP does not work well with IGP.
Thus the routers inside the AS maintain two routing tables: one for the IGP and one for IBGP. BGP uses
exterior BGP (EBGP) between different autonomous systems.
bi-directional rate shaping
A hardware-based technology that allows you to manage bandwidth on Layer 2 and Layer 3 traffic
flowing to each port on the switch and to the backplane, per physical port on the I/O module. The
parameters differ across platforms and modules.
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Glossary
blackhole
In the Extreme Networks implementation, you can configure the switch so that traffic is silently
dropped. Although this traffic appears as received, it does not appear as transmitted (because it is
dropped).
BOOTP
Bootstrap Protocol. BOOTP is an Internet protocol used by a diskless workstation to discover its own IP
address, the IP address of a BOOTP server on the network, and a file that can be loaded into memory to
boot the machine. Using BOOTP, a workstation can boot without a hard or floppy disk drive.
BPDU
Bridge protocol data unit. In STP, a BPDU is a packet that initiates communication between devices.
BPDU packets contain information on ports, addresses, priorities, and costs and they ensure that the
data ends up where it was intended to go. BPDU messages are exchanged across bridges to detect
loops in a network topology. The loops are then removed by shutting down selected bridge interfaces
and placing redundant switch ports in a backup, or blocked, state.
bridge
In conventional networking terms, bridging is a Layer 2 function that passes frames between two
network segments; these segments have a common network layer address. The bridged frames pass
only to those segments connected at a Layer 2 level, which is called a broadcast domain (or VLAN). You
must use Layer 3 routing to pass frames between broadcast domains (VLANs).
In wireless technology, bridging refers to forwarding and receiving data between radio interfaces on
APs or between clients on the same radio. So, bridged traffic can be forwarded from one AP to another
AP without having to pass through the switch on the wired network.
broadcast
A broadcast message is forwarded to all devices within a VLAN, which is also known as a broadcast
domain. The broadcast domain, or VLAN, exists at a Layer 2 level; you must use Layer 3 routing to
communicate between broadcast domains, or VLANs. Thus, broadcast messages do not leave the
VLAN. Broadcast messages are identified by a broadcast address.
BSS
Basic Service Set. A wireless topology consisting of one access point connected to a wired network and
a set of wireless devices. Also called an infrastructure network. See also IBSS.
C
captive portal
A browser-based authentication mechanism that forces unauthenticated users to a web page.
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Glossary
carrier VLAN
In STP, carrier VLANs define the scope of the STPD, including the physical and logical ports that belong
to the STPD as well as the 802.1Q tags used to transport EMISTP- or PVST+-encapsulated BPDUs. Only
one carrier VLAN can exist in any given STPD.
CCM
In CFM, connectivity check messages are CFM frames transmitted periodically by a MEP to ensure
connectivity across the maintenance entities to which the transmitting MEP belongs. The CCM
messages contain a unique ID for the specified domain. Because a failure to receive a CCM indicates a
connectivity fault in the network, CCMs proactively check for network connectivity.
CDR
Call Data (Detail) Record
. In Internet telephony, a call detail record is a data record that contains information related to a
telephone call, such as the origination and destination addresses of the call, the time the call started and
ended, the duration of the call, the time of day the call was made and any toll charges that were added
through the network or charges for operator services, among other details of the call.
In essence, call accounting is a database application that processes call data from your switch (PBX,
iPBX, or key system) via a CDR (call detail record) or SMDR (station message detail record) port. The
call data record details your system's incoming and outgoing calls by thresholds, including time of call,
duration of call, dialing extension, and number dialed. Call data is stored in a PC database.
CEP
Customer Edge Port. Also known as Selective Q-in-Q or C-tagged Service Interface. CEP is a role that is
configured in software as a CEP VMAN port, and connects a VMAN to specific CVLANs based on the
CVLAN CVID. The CNP role, which is configured as an untagged VMAN port, connects a VMAN to all
other port traffic that is not already mapped to the port CEP role.
CA certificate
A certificate identifying a certificate authority. A CA certificate can be used to verify that a certificate
issued by the certificate authority is legitimate.
certificate
A document that identifies a server or a client (user), containing a public key and signed by a certificate
authority.
Certificate Authority (CA)
A trusted third-party that generates and signs certificates. A CA may be a commercial concern, such as
GoDaddy or GeoTrust. A CA may also be an in-house server for certificates used within an enterprise.
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Glossary
certificate chain
An ordered set of certificates which can be used to verify the identity of a server or client. It begins with
a client or server certificate, and ends with a certificate that is trusted.
certificate issuer
The certificate authority that generated the certificate.
Certificate Signing Request (CSR)
A document containing identifiers, options, and a public key, that is sent to a certificate authority in
order to generate a certificate.
certificate subject
The server or client identified by the certificate.
client certificate
A certificate identifying a client (user). A client certificate can be used in conjunction with, or in lieu of, a
username and password to authenticate a client.
CFM
Connectivity Fault Management allows an ISP to proactively detect faults in the network for each
customer service instance individually and separately. CFM comprises capabilities for detecting,
verifying, and isolating connectivity failures in virtual bridged LANs.
Chalet
A web-based user interface for setting up and viewing information about a switch, removing the need
to enter common commands individually in the CLI.
CHAP
Challenge-Handshake Authentication Protocol. One of the two main authentication protocols used to
verify a user's name and password for PPP Internet connections. CHAP is more secure than because it
performs a three-way handshake during the initial link establishment between the home and remote
machines. It can also repeat the authentication anytime after the link has been established.
checkpointing
Checkpointing is the process of copying the active state configurations from the primary MSM to the
backup MSM on modular switches.
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Glossary
CIDR
Classless Inter-Domain Routing. CIDR is a way to allocate and specify the Internet addresses used in
interdomain routing more flexibly than with the original system of IP address classes. This address
aggregation scheme uses supernet addresses to represent multiple IP destinations. Rather than
advertise a separate route for each destination, a router uses a supernet address to advertise a single
route representing all destinations. RIP does not support CIDR; BGP and OSPF support CIDR.
CIST
Common and Internal Spanning Tree. In an MSTP environment, the CIST is a single spanning tree
domain that connects MSTP regions. The CIST is responsible for creating a loop-free topology by
exchanging and propagating BPDUs across MSTP regions. You can configure only one CIST on each
switch.
CIST regional root bridge
Within an MSTP region, the bridge with the lowest path cost to the CIST root bridge is the CIST regional
root bridge If the CIST root bridge is inside an MSTP region, that same bridge is the CIST regional root
for that region because it has the lowest path cost to the CIST root. If the CIST root bridge is outside an
MSTP region, all regions connect to the CIST root through their respective CIST regional roots.
CIST root bridge
In an MSTP environment, the bridge with the lowest bridge ID becomes the CIST root bridge. The bridge
ID includes the bridge priority and the MAC address. The CIST root bridge can be either inside or
outside an MSTP region. The CIST root bridge is unique for all regions and non-MSTP bridges, regardless
of its location.
CIST root port
In an MSTP environment, the port on the CIST regional root bridge that connects to the CIST root bridge
is the CIST root port. The CIST root port is the master port for all MSTIs in that MSTP region, and it is the
only port that connects the entire region to the CIST root bridge.
CLEAR-flow
CLEAR-Flow allows you to specify certain types of traffic to perform configured actions on. You can
configure the switch to take an immediate, preconfigured action to the specified traffic or to send a
copy of the traffic to a management station for analysis. CLEAR-Flow is an extension to ACLs, so you
must be familiar with ACL policy files to apply CLEAR-Flow.
CLI
Command line interface. You can use the CLI to monitor and manage the switch or wireless appliance.
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Glossary
cluster
In BGP, a cluster is formed within an AS by a route reflector and its client routers.
collision
Two Ethernet packets attempting to use the medium simultaneously. Ethernet is a shared media, so
there are rules for sending packets of data to avoid conflicts and protect data integrity. When two
nodes at different locations attempt to send data at the same time, a collision will result. Segmenting
the network with bridges or switches is one way of reducing collisions in an overcrowded network.
CNA
Converged Network Analyzer. This application suite, available from Avaya, allows the server to
determine the best possible network path. The CNA Agent is a software piece of the entire CNA
application that you install on Extreme Networks devices. You use the CNA Agent software only if you
are using the Avaya CNA solution, and the CNA Agent cannot function unless you also obtain the rest of
the CNA application from Avaya.
CNP
Customer Network Port.
combo port
Also known as a combination port. On some Extreme Networks devices (such as the Summit X450 aseries switch), certain ports can be used as either copper or fiber ports.
combo link
In EAPS, the common link is the physical link between the controller and partner nodes in a network
where multiple EAPS share a common link between domains.
control VLAN
In EAPS, the control VLAN is a VLAN that sends and receives EAPS messages. You must configure one
control VLAN for each EAPS domain.
controller node
In EAPS, the controller node is that end of the common line that is responsible for blocking ports if the
common link fails, thereby preventing a superloop.
CoS
Class of Service. Specifying the service level for the classified traffic type. For more information, see
QoS in the ExtremeXOS User Guide.
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Glossary
CRC
Cyclic Redundancy Check. This simple checksum is designed to detect transmission errors. A decoder
calculates the CRC for the received data and compares it to the CRC that the encoder calculated, which
is appended to the data. A mismatch indicates that the data was corrupted in transit.
CRC error
Cyclic redundancy check error. This is an error condition in which the data failed a checksum test used
to trap transmission errors. These errors can indicate problems anywhere in the transmission path.
CSPF
Constrained shortest path first. An algorithm based on the shortest path first algorithm used in OSPF,
but with the addition of multiple constraints arising from the network, the LSP, and the links. CSPF is
used to minimize network congestion by intelligently balancing traffic.
CVID
CVLAN ID. The CVID represents the CVLAN tag for tagged VLAN traffic. (See CVLAN.)
CVLAN
Customer VLAN.
D
DAD
Duplicate Address Detection. IPv6 automatically uses this process to ensure that no duplicate IP
addresses exist. For more information, see Duplicate Address Detection in the ExtremeXOS User Guide.
datagram
See packet.
dBm
An abbreviation for the power ratio in decibels (dB) of the measured power referenced to one milliwatt.
DCB
Data Center Bridging is a set of IEEE 802.1Q extensions to standard Ethernet, that provide an
operational framework for unifying Local Area Networks (LAN), Storage Area Networks (SAN) and
Inter-Process Communication (IPC) traffic between switches and endpoints onto a single transport
layer.
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Glossary
DCBX
The Data Center Bridging eXchange protocol is used by DCB devices to exchange DCB configuration
information with directly connected peers.
decapsulation
See tunelling.
default encapsulation mode
In STP, default encapsulation allows you to specify the type of BPDU encapsulation to use for all ports
added to a given STPD, not just to one individual port. The encapsulation modes are:
• 802.1d—This mode is used for backward compatibility with previous STP versions and for
compatibility with third-party switches using IEEE standard 802.1d.
• EMISTP—Extreme Multiple Instance Spanning Tree Protocol (EMISTP) mode is an extension of STP
that allows a physical port to belong to multiple STPDs by assigning the port to multiple VLANs.
• PVST+—This mode implements PVST+ in compatibility with third-party switches running this version
of STP.
designated port
In STP, the designated port provides the shortest path connection to the root bridge for the attached
LAN segment. Each LAN segment has only one designated port.
destination address
The IP or MAC address of the device that is to receive the packet.
Device Manager
The Device Manager is an Extreme Networks-proprietary process that runs on every node and is
responsible for monitoring and controlling all of the devices in the system. The Device Manager is useful
for system redundancy.
device server
A specialized, network-based hardware device designed to perform a single or specialized set of server
functions. Print servers, terminal servers, remote access servers, and network time servers are examples
of device servers.
DF
Don't fragment bit. This is the don't fragment bit carried in the flags field of the IP header that indicates
that the packet should not be fragmented. The remote host will return ICMP notifications if the packet
had to be split anyway, and these are used in MTU discovery.
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Glossary
DHCP
Dynamic Host Configuration Protocol. DHCP allows network administrators to centrally manage and
automate the assignment of IP addresses on the corporate network. DHCP sends a new IP address
when a computer is plugged into a different place in the network. The protocol supports static or
dynamic IP addresses and can dynamically reconfigure networks in which there are more computers
than there are available IP addresses.
DiffServ
Differentiated Services. Defined in RFC 2474 and 2475, DiffServ is an architecture for implementing
scalable service differentiation in the Internet. Each IP header has a DiffServ (DS) field, formerly known
as the Type of Service (TOS) field. The value in this field defines the QoS priority the packet will have
throughout the network by dictating the forwarding treatment given to the packet at each node.
DiffServ is a flexible architecture that allows for either end-to-end QoS or intra-domain QoS by
implementing complex classification and mapping functions at the network boundary or access points.
In the Extreme Networks implementation, you can configure the desired QoS by replacing or mapping
the values in the DS field to egress queues that are assigned varying priorities and bandwidths.
directory agent (DA)
A method of organizing and locating the resources (such as printers, disk drives, databases, e-mail
directories, and schedulers) in a network. Using SLP, networking applications can discover the existence,
location and configuration of networked devices. With Service Location Protocol, client applications are
'User Agents' and services are advertised by 'Service Agents'.
The User Agent issues a multicast 'Service Request' (SrvRqst) on behalf of the client application,
specifying the services required. The User Agent will receive a Service Reply (SrvRply) specifying the
location of all services in the network which satisfy the request.
For larger networks, a third entity, called a 'Directory Agent', receives registrations from all available
Service Agents. A User Agent sends a unicast request for services to a Directory Agent (if there is one)
rather than to a Service Agent.
(SLP version 2, RFC 2608, updating RFC 2165)
diversity antenna and receiver
The AP has two antennae. Receive diversity refers to the ability of the AP to provide better service to a
device by receiving from the user on which ever of the two antennae is receiving the cleanest signal.
Transmit diversity refers to the ability of the AP to use its two antenna to transmit on a specific antenna
only, or on a alternate antennae. The antennae are called diversity antennae because of this capability of
the pair.
DNS
Domain Name Server. This system is used to translate domain names to IP addresses. Although the
Internet is based on IP addresses, names are easier to remember and work with. All these names must
be translated back to the actual IP address and the DNS servers do so.
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Glossary
domain
In CFM, a maintenance domain is the network, or part of the network, that belongs to a single
administration for which connectivity faults are managed.
DoS attack
Denial of Service attacks occur when a critical network or computing resource is overwhelmed so that
legitimate requests for service cannot succeed. In its simplest form, a DoS attack is indistinguishable
from normal heavy traffic. ExtremeXOS software has configurable parameters that allow you to defeat
DoS attacks. For more information, see DoS Protection in the ExtremeXOS User Guide.
DR
Designated router. In OSPF, the DR generates an LSA for the multi-access network and has other
special responsibilities in the running of the protocol. The DR is elected by the OSPF protocol.
DSSS
Direct-Sequence Spread Spectrum. A transmission technology used in Local Area Wireless Network
(LAWN) transmissions where a data signal at the sending station is combined with a higher data rate bit
sequence, or chipping code, that divides the user data according to a spreading ratio. The chipping
code is a redundant bit pattern for each bit that is transmitted, which increases the signal's resistance to
interference. If one or more bits in the pattern are damaged during transmission, the original data can
be recovered due to the redundancy of the transmission. (Compare with FHSS.)
DTIM
DTIM delivery traffic indication message (in 802.11 standard).
dynamic WEP
The IEEE introduced the concept of user-based authentication using per-user encryption keys to solve
the scalability issues that surrounded static WEP. This resulted in the 802.1x standard, which makes use
of the IETF's Extensible Authentication Protocol (EAP), which was originally designed for user
authentication in dial-up networks. The 802.1x standard supplemented the EAP protocol with a
mechanism to send an encryption key to a Wireless AP. These encryption keys are used as dynamic
WEP keys, allowing traffic to each individual user to be encrypted using a separate key.
E
EAPS
Extreme Automatic Protection Switching. This is an Extreme Networks-proprietary version of the
Ethernet Automatic Protection Switching protocol that prevents looping Layer 2 of the network. This
feature is discussed in RFC 3619.
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Glossary
EAPS domain
An EAPS domain consists of a series of switches, or nodes, that comprise a single ring in a network. An
EAPS domain consists of a master node and transit nodes. The master node consists of one primary and
one secondary port. EAPS operates by declaring an EAPS domain on a single ring.
EAPS link ID
Each common link in the EAPS network must have a unique link ID. The controller and partner shared
ports belonging to the same common link must have matching link IDs, and not other instance in the
network should have that link ID.
EAP-TLS/EAP-TTLS
EAP-TLS Extensible Authentication Protocol - Transport Layer Security. A general protocol for
authentication that also supports multiple authentication methods, such as token cards, Kerberos, onetime passwords, certificates, public key authentication and smart cards.
IEEE 802.1x specifies how EAP should be encapsulated in LAN frames.
In wireless communications using EAP, a user requests connection to a WLAN through an access point,
which then requests the identity of the user and transmits that identity to an authentication server such
as RADIUS. The server asks the access point for proof of identity, which the access point gets from the
user and then sends back to the server to complete the authentication.
EAP-TLS provides for certificate-based and mutual authentication of the client and the network. It relies
on client-side and server-side certificates to perform authentication and can be used to dynamically
generate user-based and session-based WEP keys.
EAP-TTLS (Tunneled Transport Layer Security) is an extension of EAP-TLS to provide certificate-based,
mutual authentication of the client and network through an encrypted tunnel, as well as to generate
dynamic, per-user, per-session WEP keys. Unlike EAP-TLS, EAP-TTLS requires only server-side
certificates.
(See also PEAP.)
EBGP
Exterior Border Gateway Protocol. EBGP is a protocol in the IP suite designed to exchange network
reachability information with BGP systems in other autonomous systems. EBGP works between
different ASs.
ECMP
Equal Cost Multi Paths. This routing algorithm distributes network traffic across multiple highbandwidth OSPF, BGP, IS-IS, and static routes to increase performance. The Extreme Networks
implementation supports multiple equal cost paths between points and divides traffic evenly among
the available paths.
edge ports
In STP, edge ports connect to non-STP devices such as routers, endstations, and other hosts.
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Glossary
edge safeguard
Loop prevention and detection on an edge port configured for RSTP is called edge safeguard.
Configuring edge safeguard on RSTP edge ports can prevent accidental or deliberate misconfigurations
(loops) resulting from connecting two edge ports together or from connecting a hub or other non-STP
switch to an edge port. Edge safeguard also limits the impact of broadcast storms that might occur on
edge ports. This advanced loop prevention mechanism improves network resiliency but does not
interfere with the rapid convergence of edge ports. For more information about edge safeguard, see
Configuring Edge Safeguard in the ExtremeXOS User Guide.
EDP
Extreme Discovery Protocol. EDP is a protocol used to gather information about neighbor Extreme
Networks switches. Extreme Networks switches use EDP to exchange topology information.
EEPROM
Electrically erasable programmable read-only memory. EEPROM is a memory that can be electronically
programmed and erased but does not require a power source to retain data.
EGP
Exterior Gateway Protocol. EGP is an Internet routing protocol for exchanging reachability information
between routers in different autonomous systems. BGP is a more recent protocol that accomplishes this
task.
election algorithm
In ESRP, this is a user-defined criteria to determine how the master and slave interact. The election
algorithm also determines which device becomes the master or slave and how ESRP makes those
decisions.
ELRP
Extreme Loop Recovery Protocol. ELRP is an Extreme Networks-proprietary protocol that allows you to
detect Layer 2 loops.
ELSM
Extreme Link Status Monitoring. ELSM is an Extreme Networks-proprietary protocol that monitors
network health. You can also use ELSM with Layer 2 control protocols to improve Layer 2 loop recovery
in the network.
EMISTP
Extreme Multiple Instance Spanning Tree Protocol. This Extreme Networks-proprietary protocol uses a
unique encapsulation method for STP messages that allows a physical port to belong to multiple STPDs.
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Glossary
EMS
Event Management System. This Extreme Networks-proprietary system saves, displays, and filters
events, which are defined as any occurrences on a switch that generate a log message or require action.
encapsulation mode
Using STP, you can configure ports within an STPD to accept specific BPDU encapsulations. The three
encapsulation modes are:
• 802.1D—This mode is used for backward compatibility with previous STP versions and for
compatibility with third-party switches using IEEE standard 802.1D.
EMISTP—Extreme
Multiple Instance Spanning Tree Protocol mode is an extension of STP that allows
•
a physical port to belong to multiple STPDs by assigning the port to multiple VLANs.
PVST+—This
mode implements PVST+ in compatibility with third-party switches running this version
•
of STP.
EPICenter
See Ridgeline.
ESRP
Extreme Standby Router Protocol. ESRP is an Extreme Networks-proprietary protocol that provides
redundant Layer 2 and routing services to users.
ESRP-aware device
This is an Extreme Networks device that is not running ESRP itself but that is connected on a network
with other Extreme Networks switches that are running ESRP. These ESRP-aware devices also fail over.
ESRP domain
An ESRP domain allows multiple VLANs to be protected under a single logical entity. An ESRP domain
consists of one domain-master VLAN and zero or more domain-member VLANs.
ESRP-enabled device
An ESRP-enabled device is an Extreme Networks switch with an ESRP domain and ESRP enabled.
ESRP-enabled switches include the ESRP master and slave switches.
ESRP extended mode
ESRP extended mode supports and is compatible only with switches running ExtremeXOS software
exclusively.
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Glossary
ESRP group
An ESRP group runs multiple instances of ESRP within the same VLAN (or broadcast domain). To
provide redundancy at each tier, use a pair of ESRP switches on the group.
ESRP instance
You enable ESRP on a per domain basis; each time you enable ESRP is an ESRP instance.
ESRP VLAN
A VLAN that is part of an ESRP domain, with ESRP enabled, is an ESRP VLAN.
ESS
Extended Service Set. Several Basic Service Sets (BSSs) can be joined together to form one logical
WLAN segment, referred to as an extended service set (ESS). The SSID is used to identify the ESS. (See
BSS and SSID.)
ethernet
This is the IEEE 802.3 networking standard that uses carrier sense multiple access with collision
detection (CSMA/CD). An Ethernet device that wants to transmit first checks the channel for a carrier,
and if no carrier is sensed within a period of time, the device transmits. If two devices transmit
simultaneously, a collision occurs. This collision is detected by all transmitting devices, which
subsequently delay their retransmissions for a random period. Ethernet runs at speeds from 10 Mbps to
10 Gbps on full duplex.
event
Any type of occurrence on a switch that could generate a log message or require an action. For more,
see syslog.
external table
To route traffic between autonomous systems, external routing protocols and tables, such as EGP and
BGP, are used.
F
fabric module (FM)
For more information about available fabric modules, see Understanding Fabric Modules in the
BlackDiamond X8 series Switches Hardware Installation Guide.
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Glossary
fast convergence
In EAPS, Fast Convergence allows convergence in the range of 50 milliseconds. This parameter is
configured for the entire switch, not by EAPS domain.
fast path
This term refers to the data path for a packet that traverses the switch and does not require processing
by the CPU. Fast path packets are handled entirely by ASICs and are forwarded at wire speed rate.
FDB
Forwarding database. The switch maintains a database of all MAC address received on all of its ports
and uses this information to decide whether a frame should be forwarded or filtered. Each FDB entry
consists of the MAC address of the sending device, an identifier for the port on which the frame was
received, and an identifier for the VLAN to which the device belongs. Frames destined for devices that
are not currently in the FDB are flooded to all members of the VLAN. For some types of entries, you
configure the time it takes for the specific entry to age out of the FDB.
FHSS
Frequency-Hopping Spread Spectrum. A transmission technology used in Local Area Wireless Network
(LAWN) transmissions where the data signal is modulated with a narrowband carrier signal that 'hops'
in a random but predictable sequence from frequency to frequency as a function of time over a wide
band of frequencies. This technique reduces interference. If synchronized properly, a single logical
channel is maintained. (Compare with DSSS.)
FIB
Forwarding Information Base. On BlackDiamond 8800 series switches and Summit family switches, the
Layer 3 routing table is referred to as the FIB.
fit, thin, and fat APs
A thin AP architecture uses two components: an access point that is essentially a stripped-down radio
and a centralized management controller that handles the other WLAN system functions. Wired
network switches are also required.
A fit AP, a variation of the thin AP, handles the RF and encryption, while the central management
controller, aware of the wireless users' identities and locations, handles secure roaming, quality of
service, and user authentication. The central management controller also handles AP configuration and
management.
A fat (or thick) AP architecture concentrates all the WLAN intelligence in the access point. The AP
handles the radio frequency (RF) communication, as well as authenticating users, encrypting
communications, secure roaming, WLAN management, and in some cases, network routing.
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Glossary
frame
This is the unit of transmission at the data link layer. The frame contains the header and trailer
information required by the physical medium of transmission.
FQDN
Fully Qualified Domain Name. A 'friendly' designation of a computer, of the general form computer.
[subnetwork.].organization.domain. The FQDN names must be translated into an IP address in order for
the resource to be found on a network, usually performed by a DNS.
full-duplex
This is the communication mode in which a device simultaneously sends and receives over the same
link, doubling the bandwidth. Thus, a full-duplex 100 Mbps connection has a bandwidth of 200 Mbps,
and so forth. A device either automatically adjusts its duplex mode to match that of a connecting device
or you can configure the duplex mode; all devices at 1 Gbps or higher run only in full-duplex mode.
FTM
Forwarding Table Manager.
FTP
File Transfer Protocol.
G
gateway
In the wireless world, an access point with additional software capabilities such as providing NAT and
DHCP. Gateways may also provide VPN support, roaming, firewalls, various levels of security, etc.
gigabit ethernet
This is the networking standard for transmitting data at 1000 Mbps or 1 Gbps. Devices can transmit at
multiples of gigabit Ethernet as well.
gratuitous ARP
When a host sends an ARP request to resolve its own IP address, it is called gratuitous ARP. For more
information, see Gratuitous ARP Protection in the ExtremeXOS User Guide.
GUI
Graphical User Interface.
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Glossary
H
HA
Host Attach. In ExtremeXOS software, HA is part of ESRP that allows you to connect active hosts
directly to an ESRP switch; it allows configured ports to continue Layer 2 forwarding regardless of their
ESRP status.
half-duplex
This is the communication mode in which a device can either send or receive data, but not
simultaneously. (Devices at 1 Gbps or higher do not run in half-duplex mode; they run only in full-duplex
mode.)
header
This is control information (such as originating and destination stations, priority, error checking, and so
forth) added in front of the data when encapsulating the data for network transmission.
heartbeat message
A UDP data packet used to monitor a data connection, polling to see if the connection is still alive.
In general terms, a heartbeat is a signal emitted at regular intervals by software to demonstrate that it is
still alive. In networking, a heartbeat is the signal emitted by a Level 2 Ethernet transceiver at the end of
every packet to show that the collision-detection circuit is still connected.
hitless failover
In the Extreme Networks implementation on modular switches, hitless failover means that designated
configurations survive a change of primacy between the two MSMs with all details intact. Thus, those
features run seamlessly during and after control of the system changes from one MSM to another.
host
1
A computer (usually containing data) that is accessed by a user working on a remote terminal,
connected by modems and telephone lines.
2 A computer that is connected to a TCP/IP network, including the Internet. Each host has a unique IP
address.
HTTP
Hypertext Transfer Protocol is the set of rules for transferring files (text, graphic images, sound, video,
and other multimedia files) on the World Wide Web. A Web browser makes use of HTTP. HTTP is an
application protocol that runs on top of the TCP/IP suite of protocols. (RFC 2616: Hypertext Transfer
Protocol -- HTTP/1.1)
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Glossary
HTTPS
Hypertext Transfer Protocol over Secure Socket Layer, or HTTP over SSL, is a web protocol that encrypts
and decrypts user page requests as well as the pages that are returned by the Web server. HTTPS uses
Secure Socket Layer (SSL) as a sublayer under its regular HTTP application layering. (HTTPS uses port
443 instead of HTTP port 80 in its interactions with the lower layer, TCP/IP.) SSL uses a 40-bit key size
for the RC4 stream encryption algorithm, which is considered an adequate degree of encryption for
commercial exchange.
I
IBGP
Interior Border Gateway Protocol. IBGP is the BGP version used within an AS.
IBSS
Independent Basic Service Set (see BSS). An IBSS is the 802.11 term for an ad-hoc network. See ad-hoc
mode.
ICMP
Internet Control Message Protocol. ICMP is the part of the TCP/IP protocol that allows generation of
error messages, test packets, and operating messages. For example, the ping command allows you to
send ICMP echo messages to a remote IP device to test for connectivity. ICMP also supports traceroute,
which identifies intermediate hops between a given source and destination.
ICV
ICV (Integrity Check Value) is a 4-byte code appended in standard WEP to the 802.11 message.
Enhanced WPA inserts an 8-byte MIC just before the ICV. (See WPA and MIC.)
IEEE
Institute of Electrical and Electronic Engineers. This technical professional society fosters the
development of standards that often become national and international standards. The organization
publishes a number of journals and has many local chapters and several large societies in special areas.
IETF
Internet Engineering Task Force. The IETF is a large, open, international community of network
designers, operators, vendors, and researchers concerned with the evolution of the Internet architecture
and the smooth operation of the Internet. The technical work of the IETF is done in working groups,
which are organized by topic.
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Glossary
IGMP
Internet Group Management Protocol. Hosts use IGMP to inform local routers of their membership in
multicast groups. Multicasting allows one computer on the Internet to send content to multiple other
computers that have identified themselves as interested in receiving the originating computer's content.
When all hosts leave a group, the router no longer forwards packets that arrive for the multicast group.
IGMP snooping
This provides a method for intelligently forwarding multicast packets within a Layer 2 broadcast
domain. By “snooping” the IGMP registration information, the device forms a distribution list that
determines which endstations receive packets with a specific multicast address. Layer 2 switches listen
for IGMP messages and build mapping tables and associated forwarding filters. IGMP snooping also
reduces IGMP protocol traffic.
IGP
Interior Gateway Protocol. IGP refers to any protocol used to exchange routing information within an
AS. Examples of Internet IGPs include RIP and OSPF.
inline power
According to IEEE 802.3 af, inline power refers to providing an AC or DC power source through the
same cable as the data travels. It allows phones and network devices to be placed in locations that are
not near AC outlets. Most standard telephones use inline power.
infrastructure mode
An 802.11 networking framework in which devices communicate with each other by first going through
an access point. In infrastructure mode, wireless devices can communicate with each other or can
communicate with a wired network. (See ad-hoc mode and BSS.)
intermediate certificate
A certificate in the middle of a certificate chain, that bridges the trust relationship between the server
certificate and the trusted certificate.
IP
Internet Protocol. The communications protocol underlying the Internet, IP allows large, geographically
diverse networks of computers to communicate with each other quickly and economically over a
variety of physical links; it is part of the TCP/IP suite of protocols. IP is the Layer 3, or network layer,
protocol that contains addressing and control information that allows packets to be routed. IP is the
most widely used networking protocol; it supports the idea of unique addresses for each computer on
the network. IP is a connectionless, best-effort protocol; TCP reassembles the data after transmission. IP
specifies the format and addressing scheme for each packet.
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Glossary
IPC
Interprocess Communication. A capability supported by some operating systems that allows one
process to communicate with another process. The processes can be running on the same computer or
on different computers connected through a network.
IPsec/IPsec-ESP/IPsec-AH
Internet Protocol security (IPSec)
Internet Protocol security.
Encapsulating Security Payload
(IPsec-ESP)
The encapsulating security payload (ESP) encapsulates its data, enabling
it to protect data that follows in the datagram.
Internet Protocol security
Authentication Header (IPsec-AH)
AH protects the parts of the IP datagram that can be predicted by the
sender as it will be received by the receiver.
IPsec is a set of protocols developed by the IETF to support secure exchange of packets at the IP layer.
IPsec has been deployed widely to implement Virtual Private Networks (VPNs).
IPsec supports two encryption modes: Transport and Tunnel. Transport mode encrypts only the data
portion (payload) of each packet, but leaves the header untouched. The more secure Tunnel mode
encrypts both the header and the payload. On the receiving side, an IPSec-compliant device decrypts
each packet.
For IPsec to work, the sending and receiving devices must share a public key. This is accomplished
through a protocol known as Internet Security Association and Key Management Protocol/Oakley
(ISAKMP/Oakley), which allows the receiver to obtain a public key and authenticate the sender using
digital certificates.
IPv6
Internet Protocol version 6. IPv6 is the next-generation IP protocol. The specification was completed in
1997 by IETF. IPv6 is backward- compatible with and is designed to fix the shortcomings of IPv4, such
as data security and maximum number of user addresses. IPv6 increases the address space from 32 to
128 bits, providing for an unlimited (for all intents and purposes) number of networks and systems; IPv6
is expected to slowly replace IPv4, with the two existing side by side for many years.
IP address
IP address is a 32-bit number that identifies each unique sender or receiver of information that is sent in
packets; it is written as four octets separated by periods (dotted-decimal format). An IP address has
two parts: the identifier of a particular network and an identifier of the particular device (which can be a
server or a workstation) within that network. You may add an optional sub-network identifier. Only the
network part of the address is looked at between the routers that move packets from one point to
another along the network. Although you can have a static IP address, many IP addresses are assigned
dynamically from a pool. Many corporate networks and online services economize on the number of IP
addresses they use by sharing a pool of IP addresses among a large number of users. (The format of the
IP address is slightly changed in IPv6.)
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Glossary
IPTV
Internal Protocol television. IPTV uses a digital signal sent via broadband through a switched telephone
or cable system. An accompanying set top box (that sits on top of the TV) decodes the video and
converts it to standard television signals.
IR
Internal router. In OSPF, IR is an internal router that has all interfaces within the same area.
IRDP
Internet Router Discovery Protocol. Used with IP, IRDP enables a host to determine the address of a
router that it can use as a default gateway. In Extreme Networks implementation, IP multinetting
requires a few changes for the IRDP.
ISO
This abbreviation is commonly used for the International Organization for Standardization, although it is
not an acronym. ISO was founded in 1946 and consists of standards bodies from more than 75 nations.
ISO had defined a number of important computer standards, including the OSI reference model used as
a standard architecture for networking.
isochronous
Isochronous data is data (such as voice or video) that requires a constant transmission rate, where data
must be delivered within certain time constraints. For example, multimedia streams require an
isochronous transport mechanism to ensure that data is delivered as fast as it is displayed and to ensure
that the audio is synchronized with the video. Compare: asynchronous processes in which data streams
can be broken by random intervals, and synchronous processes, in which data streams can be delivered
only at specific intervals.
ISP
An Internet Service Provider is an organization that provides access to the Internet. Small ISPs provide
service via modem and ISDN while the larger ones also offer private line hookups (T1, fractional T1, etc.).
Customers are generally billed a fixed rate per month, but other charges may apply. For a fee, a Web
site can be created and maintained on the ISP's server, allowing the smaller organization to have a
presence on the Web with its own domain name.
ITU-T
International Telecommunication Union-Telecommunication. The ITU-T is the telecommunications
division of the ITU international standards body.
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Glossary
IV
Initialization Vector. Part of the standard WEP encryption mechanism that concatenates a shared secret
key with a randomly generated 24-bit initialization vector. WPA with TKIP uses 48-bit IVs, an
enhancement that significantly increases the difficulty in cracking the encryption. (See WPA and TKIP.)
J
jumbo frames
Ethernet frames larger than 1522 bytes (including the 4 bytes in the CRC). The jumbo frame size is
configurable on Extreme Networks devices; the range is from 1523 to 9216 bytes.
L
LACP
Link Aggregation Control Protocol. LACP is part of the IEEE 802.3ad and automatically configures
multiple aggregated links between switches.
LAG
Link aggregation group. A LAG is the logical high-bandwidth link that results from grouping multiple
network links in link aggregation (or load sharing). You can configure static LAGs or dynamic LAGs
(using the LACP).
Layer 2
Layer 2 is the second, or data link, layer of the OSI model, or the MAC layer. This layer is responsible for
transmitting frames across the physical link by reading the hardware, or MAC, source and destination
addresses.
Layer 3
Layer 3 is the third layer of the OSI model. Also known as the network layer, Layer 3 is responsible for
routing packets to different LANs by reading the network address.
LED
Light-emitting diode. LEDs are on the device and provide information on various states of the device’s
operation. See your hardware documentation for a complete explanation of the LEDs on devices
running ExtremeXOS.
legacy certificate
The certificates that shipped with NetSight and NAC 4.0.0 and earlier.
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Glossary
LFS
Link Fault Signal. LFS, which conforms to IEEE standard 802.3ae-2002, monitors 10 Gbps ports and
indicates either remote faults or local faults.
license
ExtremeXOS version 11.1 introduces a licensing feature to the ExtremeXOS software. You must have a
license, which you obtain from Extreme Networks, to apply the full functionality of some features.
link aggregation
Link aggregation, also known as trunking or load sharing, conforms to IEEE 802.3ad. This feature is the
grouping of multiple network links into one logical high-bandwidth link.
link type
In OSPF, there are four link types that you can configure: auto, broadcast, point-to-point, and passive.
LLDP
Link Layer Discovery Protocol. LLDP conforms to IEEE 802.1ab and is a neighbor discovery protocol.
Each LLDP-enabled device transmits information to its neighbors, including chassis and port
identification, system name and description, VLAN names, and other selected networking information.
The protocol also specifies timing intervals in order to ensure current information is being transmitted
and received.
load sharing
Load sharing, also known as trunking or link aggregation, conforms to IEEE 802.3ad. This feature is the
grouping of multiple network links into one logical high-bandwidth link. For example, by grouping four
100 Mbps of full-duplex bandwidth into one logical link, you can create up to 800 Mbps of bandwidth.
Thus, you increase bandwidth and availability by using a group of ports to carry traffic in parallel
between switches.
loop detection
In ELRP, loop detection is the process used to detect a loop in the network. The switch sending the
ELRP PDU waits to receive its original PDU back. If the switch received this original PDU, there is a loop
in the network.
LSA
Link state advertisement. An LSA is a broadcast packet used by link state protocols, such as OSPF. The
LSA contains information about neighbors and path costs and is used by the receiving router to
maintain a routing table.
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Glossary
LSDB
Link state database. In OSPF, LSDB is a database of information about the link state of the network. Two
neighboring routers consider themselves to be adjacent only if their LSDBs are synchronized. All routing
information is exchanged only between adjacent routers.
M
MAC
Media Access Control layer. One of two sub-layers that make up the Data Link Layer of the OSI model.
The MAC layer is responsible for moving data packets to and from one NIC to another across a shared
channel.
MAC address
Media access control address. The MAC address, sometimes known as the hardware address, is the
unique physical address of each network interface card on each device.
MAN
Metropolitan area network. A MAN is a data network designed for a town or city. MANs may be
operated by one organization such as a corporation with several offices in one city, or be shared
resources used by several organizations with several locations in the same city. MANs are usually
characterized by very high-speed connections.
master node
In EAPS, the master node is a switch, or node, that is designated the master in an EAPS domain ring.
The master node blocks the secondary port for all non-control traffic belonging to this EAPS domain,
thereby avoiding a loop in the ring.
master router
In VRRP, the master router is the physical device (router) in the VRRP virtual router that is responsible
for forwarding packets sent to the VRRP virtual router and for responding to ARP requests. The master
router sends out periodic advertisements that let backup routers on the network know that it is alive. If
the VRRP IP address owner is identified, it always becomes the master router.
master VLAN
In ESRP, the master VLAN is the VLAN on the ESRP domain that exchanges ESRP-PDUs and data
between a pair of ESRP-enabled devices. You must configure one master VLAN for each ESRP domain,
and a master VLAN can belong to only one ESRP domain.
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Glossary
MED
Multiple exit discriminator. BGP uses the MED metric to select a particular border router in another AS
when multiple border routers exist.
member VLAN
In ESRP, you configure zero or more member VLANs for each ESRP domain. A member VLAN can
belong to only one ESRP domain. The state of the ESRP device determines whether the member VLAN
is in forwarding or blocking state.
MEP
In CFM, maintenance end point is an end point for a single domain, or maintenance association. The
MEP may be either an UP MEP or a DOWN MEP.
metering
In QoS, metering monitors the traffic pattern of each flow against the traffic profile. For out-of-profile
traffic the metering function interacts with other components to either re-mark or drop the traffic for
that flow. In the Extreme Networks implementation, you use ACLs to enforce metering.
MIB
Management Information Base. MIBs make up a database of information (for example, traffic statistics
and port settings) that the switch makes available to network management systems. MIB names
identify objects that can be managed in a network and contain information about the objects. MIBs
provide a means to configure a network device and obtain network statistics gathered by the device.
Standard, minimal MIBs have been defined, and vendors often have private enterprise MIBs.
MIC
Message Integrity Check or Code (MIC), also called ‘Michael’, is part of WPA and TKIP. The MIC is an
additional 8-byte code inserted before the standard 4-byte integrity check value (ICV) that is appended
in by standard WEP to the 802.11 message. This greatly increases the difficulty in carrying out forgery
attacks.
Both integrity check mechanisms are calculated by the receiver and compared against the values sent
by the sender in the frame. If the values match, there is assurance that the message has not been
tampered with. (See WPA, TKIP, and ICV.)
MIP
In CFM, the maintenance intermediate point is intermediate between endpoints. Each MIP is associated
with a single domain, and there may be more than one MIP in a single domain.
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Glossary
mirroring
Port mirroring configures the switch to copy all traffic associated with one or more ports to a
designated monitor port. The monitor port can be connected to an network analyzer or RMON probe
for packet analyzer.
MLAG
Multi-switch Link Aggregation Group (a.k.a. Multi-Chassis Link Aggregation Group). This feature allows
users to combine ports on two switches to form a single logical connection to another network device.
The other network device can be either a server or a switch that is separately configured with a regular
LAG (or appropriate server port teaming) to form the port aggregation.
MM
Management Module. For more information, see Understanding Management Modules in the
BlackDiamond X8 series Switches Hardware Installation Guide.
MMF
Multimode fiber. MMF is a fiber optic cable with a diameter larger than the optical wavelength, in which
more than one bound mode can propagate. Capable of sending multiple transmissions simultaneously,
MMF is commonly used for communications of 2 km or less.
MSDP
Multicast Source Discovery Protocol. MSDP is used to connect multiple multicast routing domains.
MSDP advertises multicast sources across Protocol Independent Multicast-Sparse Mode (PIM-SM)
multicast domains orRendezvous Points (RPs). In turn, these RPs run MSDP over TCP to discover
multicast sources in other domains.
MSM
Master Switch Fabric Module. This Extreme Networks-proprietary name refers to the module that holds
both the control plane and the switch fabric for switches that run the ExtremeXOS software on modular
switches. One MSM is required for switch operation; adding an additional MSM increases reliability and
throughput. Each MSM has two CPUs. The MSM has LEDs as well as a console port, management port,
modem port, and compact flash; it may have data ports as well. The MSM is responsible for upper-layer
protocol processing and system management functions. When you save the switch configuration, it is
saved to all MSMs.
MSTI
Multiple Spanning Tree Instances. MSTIs control the topology inside an MSTP region. An MSTI is a
spanning tree domain that operates within a region and is bounded by that region; and MSTI does not
exchange BPDUs or send notifications to other regions. You can map multiple VLANs to an MSTI;
however, each VLAN can belong to only one MSTI.You can configure up to 64 MSTIs in an MSTP region.
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MSTI regional root bridge
In an MSTP environment, each MSTI independently elects its own root bridge. The bridge with the
lowest bridge ID becomes the MSTI regional root bridge. The bridge ID includes the bridge priority and
the MAC address.
MSTI root port
In an MSTP environment, the port on the bridge with the lowest path cost to the MSTI regional root
bridge is the MSTI root port.
MSTP
Multiple Spanning Tree Protocol. MSTP, based on IEEE 802.1Q-2003 (formerly known as IEEE 892.1s),
allows you to bundle multiple VLANs into one spanning tree (STP) topology, which also provides
enhanced loop protection and better scaling. MSTP uses RSTP as the converging algorithm and is
compatible with legacy STP protocols.
MSTP region
An MSTP region defines the logical boundary of the network. Interconnected bridges that have the
same MSTP configuration are referred to as an MSTP region. Each MSTP region has a unique identifier, is
bound together by one CIST that spans the entire network, and contains from 0 to 64 MSTIs. A bridge
participates in only one MSTP region at one time. An MSTP topology is individual MSTP regions
connected either to the rest of the network with 802.1D and 802.1w bridges or to each other.
MTU
Maximum transmission unit. This term is a configurable parameter that determines the largest packet
than can be transmitted by an IP interface (without the packet needing to be broken down into smaller
units).
Note
Packets that are larger than the configured MTU size are dropped at the ingress port. Or, if
configured to do so, the system can fragment the IPv4 packets and reassemble them at the
receiving end.
multicast
Multicast messages are transmitted to selected devices that specifically join the multicast group; the
addresses are specified in the destination address field. In other words, multicast (point-to-multipoint)
is a communication pattern in which a source host sends a message to a group of destination hosts.
multinetting
IP multinetting assigns multiple logical IP interfaces on the same circuit or physical interface. This allows
one bridge domain (VLAN) to have multiple IP networks.
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MVR
Multicast VLAN registration. MVR allows a subscriber on a port to subscribe and unsubscribe to a
multicast stream on the network-wide multicast VLAN; it allows the single multicast VLAN to be shared
in the network while subscribers remain in separate VLANs. MVR provides the ability to continuously
send multicast streams in the multicast VLAN, but to isolate the The application from the subscriber
VLANs for bandwidth and security reasons. MVR allows a multicast stream received over a Layer 2
VLAN to be forwarded to another VLAN, eliminating the need for a Layer 3 routing protocol; this
feature is often used for IPTV applications.
N
NAS
Network Access Server. This is server responsible for passing information to designated RADIUS servers
and then acting on the response returned. A NAS-Identifier is a RADIUS attribute identifying the NAS
server. (RFC 2138)
NAT
Network Address Translation (or Translator). This is a network capability that enables a group of
computers to dynamically share a single incoming IP address. NAT takes the single incoming IP address
and creates a new IP address for each client computer on the network.
netlogin
Network login provides extra security to the network by assigning addresses only to those users who
are properly authenticated. You can use web-based, MAC-based, or IEEE 802.1X-based authentication
with network login. The two modes of operation are campus mode and ISP mode.
netmask
A netmask is a string of 0s and 1s that mask, or screen out, the network part of an IP address, so that
only the host computer part of the address remains. A frequently-used netmask is 255.255.255.0, used
for a Class C subnet (one with up to 255 host computers). The ".0" in the netmask allows the specific
host computer address to be visible.
neutral state/switch
In ESRP, the neutral state is the initial state entered by the switch. In a neutral state, the switch waits for
ESRP to initialize and run. A neutral switch does not participate in ESRP elections.
NIC
Network Interface Card. An expansion board in a computer that connects the computer to a network.
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NLRI
Network layer reachability information. In BGP, the system sends routing update messages containing
NLRI to describe a route and how to get there. A BGP update message carries one or more NLRI
prefixes and the attributes of a route for each NLRI prefix; the route attributes include a BGP next hop
gateway address, community values, and other information.
NMS
Network Management System. The system responsible for managing a network or a portion of a
network. The NMS talks to network management agents, which reside in the managed nodes.
node
In general networking terms, a node is a device on the network. In the Extreme Networks
implementation, a node is a CPU that runs the management application on the switch. Each MSM on
modular switches installed in the chassis is a node.
node manager
The node manager performs the process of node election, which selects the master, or primary, MSM
when you have two MSMs installed in the modular chassis. The node manager is useful for system
redundancy.
NSSA
Not-so-stubby area. In OSPF, NSSA is a stub area, which is connected to only one other area, with
additional capabilities:
• External routes originating from an ASBR connected to the NSSA can be advertised within the
NSSA.
External
routes originating from the NSSA can be propagated to other areas.
•
NTP
Network Time Protocol, an Internet standard protocol (built on top of TCP/IP) that assures accurate
synchronization to the millisecond of computer clock times in a network of computers. Based on UTC,
NTP synchronizes client workstation clocks to the U.S. Naval Observatory Master Clocks in Washington,
DC and Colorado Springs CO. Running as a continuous background client program on a computer, NTP
sends periodic time requests to servers, obtaining server time stamps and using them to adjust the
client's clock. (RFC 1305)
O
odometer
In the Extreme Networks implementation, each field replaceable component contains a system
odometer counter in EEPROM.
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On modular switches, using the CLI, you can display how long each following individual component has
been in service:
• chassis
• MSMs
• I/O modules
• power controllers
On standalone switches, you display the days of service for the switch.
OFDM
Orthogonal frequency division multiplexing, a method of digital modulation in which a signal is split into
several narrowband channels at different frequencies. OFDM is similar to conventional frequency
division multiplexing (FDM). The difference lies in the way in which the signals are modulated and
demodulated. Priority is given to minimizing the interference, or crosstalk, among the channels and
symbols comprising the data stream. Less importance is placed on perfecting individual channels.
OFDM is used in European digital audio broadcast services. It is also used in wireless local area
networks.
OID
Object identifier.
option 82
This is a security feature that you configure as part of BOOTP/DHCP. Option 82 allows a server to bind
the client's port, IP address, and MAC number for subscriber identification.
OSI
Open Systems Interconnection. OSI is an ISO standard for worldwide communications that defines a
networking framework for implementing protocols in seven layers. Control is passed from one layer to
the next, starting at the application layer in one station, down through the presentation, session,
transport, network, data link layer to the physical layer at the bottom, over the channel to the next
station and back up the hierarchy.
OSI Layer 2
At the Data Link layer (OSI Layer 2), data packets are encoded and decoded into bits. The data link layer
has two sub-layers:
• The Logical Link Control (LLC) layer controls frame synchronization, flow control and error checking.
• The Media Access Control (MAC) layer controls how a computer on the network gains access to the
data and permission to transmit it.
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OSI Layer 3
The Network layer (OSI Layer 3) provides switching and routing technologies, creating logical paths,
known as virtual circuits, for transmitting data from node to node. Routing and forwarding are functions
of this layer, as well as addressing, inter-networking, error handling, congestion control and packet
sequencing.
OSI reference model
The seven-layer standard model for network architecture is the basis for defining network protocol
standards and the way that data passes through the network. Each layer specifies particular network
functions; the highest layer is closest to the user, and the lowest layer is closest to the media carrying
the information. So, in a given message between users, there will be a flow of data through each layer at
one end down through the layers in that computer and, at the other end, when the message arrives,
another flow of data up through the layers in the receiving computer and ultimately to the end user or
program. This model is used worldwide for teaching and implementing networking protocols.
OSPF
Open Shortest Path First. An interior gateway routing protocol for TCP/IP networks, OSPF uses a link
state routing algorithm that calculates routes for packets based on a number of factors, including least
hops, speed of transmission lines, and congestion delays. You can also configure certain cost metrics for
the algorithm. This protocol is more efficient and scalable than vector-distance routing protocols. OSPF
features include least-cost routing, ECMP routing, and load balancing. Although OSPF requires CPU
power and memory space, it results in smaller, less frequent router table updates throughout the
network. This protocol is more efficient and scalable than vector-distance routing protocols.
OSPFv3
OSPFv3 is one of the routing protocols used with IPV6 and is similar to OSPF.
OUI
Organizational(ly) Unique Identifier. The OUI is the first 24 bits of a MAC address for a network device
that indicate a specific vendor as assigned by IEEE.
P
packet
This is the unit of data sent across a network. Packet is a generic term used to describe units of data at
all levels of the protocol stack, but it is most correctly used to describe application data units. The
packet is a group of bits, including data and control signals, arranged in a specific format. It usually
includes a header, with source and destination data, and user data. The specific structure of the packet
depends on the protocol used.
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PAP
Password Authentication Protocol. This is the most basic form of authentication, in which a user's name
and password are transmitted over a network and compared to a table of name-password pairs.
Typically, the passwords stored in the table are encrypted. (See CHAP.)
partner node
In EAPS, the partner node is that end of the common link that is not a controller node; the partner node
does not participate in any form of blocking.
PD
Powered device. In PoE, the PD is the powered device that plugs into the PoE switch.
PDU
Protocol data unit. A PDU is a message of a given protocol comprising payload and protocol-specific
control information, typically contained in a header.
PEAP
Protected Extensible Authentication Protocol. PEAP is an IETF draft standard to authenticate wireless
LAN clients without requiring them to have certificates. In PEAP authentication, first the user
authenticates the authentication server, then the authentication server authenticates the user. If the first
phase is successful, the user is then authenticated over the SSL tunnel created in phase one using EAPGeneric Token Card (EAP-GTC) or Microsoft Challenged Handshake Protocol Version 2 (MSCHAP V2).
(See also EAP-TLS.)
PEC
Power Entry Circuit.
PEM
Power Entry Module.
PIM-DM
Protocol-Independent Multicast - Dense mode. PIM-DM is a multicast protocol that uses Reverse Path
Forwarding but does not require any particular unicast protocol. It is used when recipients are in a
concentrated area.
PIM-SM
Protocol-Independent Multicast - Sparse mode. PIM-SM is a multicast protocol that defines a
rendezvous point common to both sender and receiver. Sender and receiver initiate communication at
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Glossary
the rendezvous point, and the flow begins over an optimized path. It is used when recipients are in a
sparse area.
ping
Packet Internet Groper. Ping is the ICMP echo message and its reply that tests network reachability of a
device. Ping sends an echo packet to the specified host, waits for a response, and reports success or
failure and statistics about its operation.
PKCS #8 (Public-Key Cryptography Standard #8)
One of several standard formats which can be used to store a private key in a file. It can optionally be
encrypted with a password.
PKI
Public Key Infrastructure.
PMBR
PIM multicast border router. A PIMBR integrates PIM-DM and PIM-SM traffic.
PoE
Power over Ethernet. The PoE standard (IEEE 802.3af) defines how power can be provided to network
devices over existing Ethernet connections, eliminating the need for additional external power supplies.
policy files
You use policy files in ExtremeXOS to specify ACLs and policies. A policy file is a text file (with a .pol
extension) that specifies a number of conditions to test and actions to take. For ACLs, this information is
applied to incoming traffic at the hardware level. Policies are more general and can be applied to
incoming routing information; they can be used to rewrite and modify routing advertisements.
port mirroring
Port mirroring configures the switch to copy all traffic associated with one or more ports to a
designated monitor port. A packet bound for or heading away from the mirrored port is forwarded onto
the monitor port as well. The monitor port can be connected to a network analyzer or RMON probe for
packet analysis. Port mirroring is a method of monitoring network traffic that a network administrator
uses as a diagnostic tool or debugging feature; it can be managed locally or remotely.
POST
Power On Self Test. On Extreme Networks switches, the POST runs upon powering-up the device. Once
the hardware elements are determined to be present and powered on, the boot sequence begins. If the
MGMT LED is yellow after the POST completes, contact your supplier for advice.
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primary port
In EAPS, a primary port is a port on the master node that is designated the primary port to the ring.
protected VLAN
In STP, protected VLANs are the other (other than the carrier VLAN) VLANs that are members of the
STPD but do not define the scope of the STPD. Protected VLANs do not transmit or receive STP BPDUs,
but they are affected by STP state changes and inherit the state of the carrier VLAN. Also known as
non-carrier VLANs, they carry the data traffic.
In EAPS, a protected VLAN is a VLAN that carries data traffic through an EAPS domain. You must
configure one or more protected VLANs for each EAPS domain. This is also known as a data VLAN.
proxy ARP
This is the technique in which one machine, usually a router, answers ARP requests intended for another
machine. By masquerading its identity (as an endstation), the router accepts responsibility for routing
packets to the real destination. Proxy ARP allows a site to use a single IP address with two physical
networks. Subnetting is normally a better solution.
pseudowire
Sometimes spelled as "pseudo-wire" or abbreviated as PW. As described in RFC 3985, there are
multiple methods for carrying networking services over a packet-switched network. In short, a
pseudowire emulates networking or telecommunication services across packet-switched networks that
use Ethernet, IP, or MPLS. Emulated services include T1 leased line, frame relay, Ethernet, ATM, TDM, or
SONET/SDH.
push-to-talk (PTT)
The push-to-talk is feature on wireless telephones that allows them to operate like a walkie-talkie in a
group, instead of standard telephone operation. The PTT feature requires that the network be
configured to allow multicast traffic.
A PTT call is initiated by selecting a channel and pressing the 'talk' key on the wireless telephone. All
wireless telephones on the same network that are monitoring the channel will hear the transmission. On
a PTT call you hold the button to talk and release it to listen.
PVST+
Per VLAN Spanning Tree +. This implementation of STP has a 1:1 relationship with VLANs. The Extreme
Networks implementation of PVST+ allows you to interoperate with third-party devices running this
version of STP. PVST is a earlier version of this protocol and is compatible with PVST+.
Q
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QoS
Quality of Service. Policy-enabled QoS is a network service that provides the ability to prioritize
different types of traffic and to manage bandwidth over a network. QoS uses various methods to
prioritize traffic, including IEEE 802.1p values and IP DiffServ values. QoS features provide better
network service by supporting dedicated bandwidth, improving loss characteristics, avoiding and
managing network congestion, shaping network traffic, and setting traffic priorities across the network.
(RFC 2386)
R
radar
Radar is a set of advanced, intelligent, Wireless-Intrusion-Detection-Service-Wireless-IntrusionPrevention-Service (WIDS-WIPS) features that are integrated into the Wireless Controller and its access
points (APs). Radar provides a basic solution for discovering unauthorized devices within the wireless
coverage area. Radar performs basic RF network analysis to identify unmanaged APs and personal adhoc networks. The Radar feature set includes: intrusion detection, prevention and interference
detection.
RADIUS
Remote Authentication Dial In User Service. RADIUS is a client/server protocol and software that
enables remote access servers to communicate with a central server to authenticate dial-in users and
authorize their access to the requested system or service. RADIUS allows a company to maintain user
profiles in a central database that all remote servers can share. It provides better security, allowing a
company to set up a policy that can be applied at a single administered network point. With RADIUS,
you can track usage for billing and for keeping network statistics.
RARP
Reverse ARP. Using this protocol, a physical device requests to learn its IP address from a gateway
server's ARP table. When a new device is set up, its RARP client program requests its IP address from
the RARP server on the router. Assuming that an entry has been set up in the router table, the RARP
server will return the IP address to the machine which can store it for future use.
rate limiting
In QoS, rate limiting is the process of restricting traffic to a peak rate (PR). For more information, see
rate limiting and rate shaping in the ExtremeXOS User Guide.
rate shaping
In QoS, rate shaping is the process of reshaping traffic throughput to give preference to higher priority
traffic or to buffer traffic until forwarding resources become available. For more information, see rate
limiting and rate shaping in the ExtremeXOS User Guide.
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RF
Radio Frequency. A frequency in the electromagnetic spectrum associated with radio wave
propagation. When an RF current is supplied to an antenna, an electromagnetic field is created that can
propagate through space. These frequencies in the electromagnetic spectrum range from Ultra-low
frequency (ULF):0-3 Hz to Extremely high frequency (EHF): 30 GHz–300 GHz. The middle ranges are:
Low frequency (LF): 30 kHz–300 kHz; Medium frequency (MF): 300 kHz–3 MHz; High frequency (HF): 3
MHz–30 MHz; Very high frequency (VHF): 30 MHz–300 MHz; and Ultra-high frequency (UHF): 300
MHz–3 GHz.
RFC
Request for Comment. The IETF RFCs describe the definitions and parameters for networking. The
RFCs are catalogued and maintained on the IETF RFC website: www.ietf.org/rfc.html.
Ridgeline
Ridgeline is an Extreme Networks-proprietary graphical user interface (GUI) network management
system. The name was changed from EPICenter to Ridgeline in 2011.
RIP
Routing Information Protocol. This IGP vector-distance routing protocol is part of the TCP/IP suite and
maintains tables of all known destinations and the number of hops required to reach each. Using RIP,
routers periodically exchange entire routing tables. RIP is suitable for use only as an IGP.
RIPng
RIP next generation. RIPng is one of the routing protocols used with IPv6 and is similar to RIP.
RMON
Remote monitoring. RMON is a standardized method to make switch and router information available to
remote monitoring applications. It is an SNMP network management protocol that allows network
information to be gathered remotely. RMON collects statistics and enables a management station to
monitor network devices from a central location. It provides multivendor interoperability between
monitoring devices and management stations. RMON is described in several RFCs (among them IETF
RFC 1757 and RFC 2201).
Network administrators use RMON to monitor, analyze, and troubleshoot the network. A software agent
can gather the information for presentation to the network administrator with a graphical user interface
(GUI). The administrator can find out how much bandwidth each user is using and what web sites are
being accessed; you can also set alarms to be informed of potential network problems.
roaming
In 802.11, roaming occurs when a wireless device (a station) moves from one Access Point to another (or
BSS to another) in the same Extended Service Set (ESS) -identified by its SSID.
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root bridge
In STP, the root bridge is the bridge with the best bridge identifier selected to be the root bridge. The
network has only one root bridge. The root bridge is the only bridge in the network that does not have a
root port.
root port
In STP, the root port provides the shortest path to the root bridge. All bridges except the root bridge
contain one root port.
route aggregation
In BGP, you can combine the characteristics of several routes so they are advertised as a single route,
which reduces the size of the routing tables.
route flapping
A route is flapping when it is repeatedly available, then unavailable, then available, then unavailable. In
the ExtremeXOS BGP implementation, you can minimize the route flapping using the route flap
dampening feature.
route reflector
In BGP, you can configure the routers within an AS such that a single router serves as a central routing
point for the entire AS.
routing confederation
In BGP, you can configure a fully meshed autonomous system into several sub-ASs and group these
sub-ASs into a routing confederation. Routing confederations help with the scalability of BGP.
RP-SMA
Reverse Polarity-Subminiature version A, a type of connector used with wireless antennas.
RSN
Robust Security Network. A new standard within IEEE 802.11 to provide security and privacy
mechanisms. The RSN (and related TSN) both specify IEEE 802.1x authentication with Extensible
Authentication Protocol (EAP).
RSSI
RSSI received signal strength indication (in 802.11 standard).
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RTS/CTS
RTS request to send, CTS clear to send (in 802.11 standard).
RSTP
Rapid Spanning Tree Protocol. RSTP, described in IEEE 802.1w, is an enhanced version of STP that
provides faster convergence. The Extreme Networks implementation of RSTP allows seamless
interoperability with legacy STP.
S
SA
Source address. The SA is the IP or MAC address of the device issuing the packet.
SCP
Secure Copy Protocol. SCP2, part of SSH2, is used to transfer configuration and policy files.
SDN
Software-defined Networking. An approach to computer networking that seeks to manage network
services through decoupling the system that makes decisions about where traffic is sent (control plane)
from the underlying systems that forward traffic to the selected destination (data plan).
secondary port
In EAPS, the secondary port is a port on the master node that is designated the secondary port to the
ring. The transit node ignores the secondary port distinction as long as the node is configured as a
transit node.
segment
In Ethernet networks, a section of a network that is bounded by bridges, routers, or switches. Dividing a
LAN segment into multiple smaller segments is one of the most common ways of increasing available
bandwidth on the LAN.
server certificate
A certificate identifying a server. When a client connects to the server, the server sends its certificate to
the client and the client validates the certificate to trust the server.
sFlow
sFlow allows you to monitor network traffic by statistically sampling the network packets and
periodically gathering the statistics. The sFlow monitoring system consists of an sFlow agent
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(embedded in a switch, router, or stand-alone probe) and an external central data collector, or sFlow
analyzer.
SFP
Small form-factor pluggable. These transceivers offer high speed and physical compactness.
slow path
This term refers to the data path for packets that must be processed by the switch CPU, whether these
packets are generated by the CPU, removed from the network by the CPU, or simply forwarded by the
CPU.
SLP
Service Location Protocol. A method of organizing and locating the resources (such as printers, disk
drives, databases, e-mail directories, and schedulers) in a network.
Using SLP, networking applications can discover the existence, location and configuration of networked
devices.
With Service Location Protocol, client applications are 'User Agents' and services are advertised by
'Service Agents'. The User Agent issues a multicast 'Service Request' (SrvRqst) on behalf of the client
application, specifying the services required. The User Agent will receive a Service Reply (SrvRply)
specifying the location of all services in the network which satisfy the request.
For larger networks, a third entity, called a 'Directory Agent', receives registrations from all available
Service Agents. A User Agent sends a unicast request for services to a Directory Agent (if there is one)
rather than to a Service Agent.
(SLP version 2, RFC2608, updating RFC2165)
SMF
Single-mode fiber. SMF is a laser-driven optical fiber with a core diameter small enough to limit
transmission to a single bound mode. SMF is commonly used in long distance transmission of more than
three miles; it sends one transmission at a time.
SMI
Structure of Management Information. A hierarchical tree structure for information that underlies
Management Information Bases (MIBs), and is used by the SNMP protocol. Defined in RFC 1155 and RFC
1442 (SNMPv2).
SMON
Switch Network Monitoring Management (MIB) system defined by the IETF document RFC 2613. SMON
is a set of MIB extensions for RMON that allows monitoring of switching equipment from a SNMP
Manager in greater detail.
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SMT
Station Management. The object class in the 802.11 MIB that provides the necessary support at the
station to manage the processes in the station such that the station may work cooperatively as a part of
an IEEE 802.11 network. The four branches of the 802.11 MIB are:
• dot11smt—objects related to station management and local configuration
• dot11mac—objects that report/configure on the status of various MAC parameters
• dot11res—objects that describe available resources
• dot11phy—objects that report on various physical items
SNMP
Simple Network Management Protocol. SNMP is a standard that uses a common software agent to
remotely monitor and set network configuration and runtime parameters. SNMP operates in a
multivendor environment, and the agent uses MIBs, which define what information is available from any
manageable network device. You can also set traps using SNMP, which send notifications of network
events to the system log.
SNTP
Simple Network Time Protocol. SNTP is used to synchronize the system clocks throughout the network.
An extension of the Network Time Protocol, SNTP can usually operate with a single server and allows
for IPv6 addressing.
SSH
Secure Shell, sometimes known as Secure Socket Shell, is a UNIX-based command interface and
protocol of securely gaining access to a remote computer. With SSH commands, both ends of the
client/server connection are authenticated using a digital certificate, and passwords are protected by
being encrypted. At Extreme Networks, the SSH is a separate software module, which must be
downloaded separately. (SSH is bundled with SSL in the software module.)
SSID
Service Set Identifier. A 32-character unique identifier attached to the header of packets sent over a
Wireless LAN that acts as a password when a wireless device tries to connect to the Basic Service Set
(BSSs). Several BSSs can be joined together to form one logical WLAN segment, referred to as an
extended service set (ESS). The SSID is used to identify the ESS.
In 802.11 networks, each access point (AP) advertises its presence several times per second by
broadcasting beacon frames that carry the ESS name (SSID). Stations discover APs by listening for
beacons, or by sending probe frames to search for an AP with a desired SSID. When the station locates
an appropriately-named access point, it sends an associate request frame containing the desired SSID.
The AP replies with an associate response frame, also containing the SSID.
Some APs can be configured to send a zero-length broadcast SSID in beacon frames instead of sending
their actual SSID. The AP must return its actual SSID in the probe response.
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SSL
Secure Sockets Layer. SSL is a protocol for transmitting private documents using the Internet. SSL
works by using a public key to encrypt data that is transferred over the SSL connection. SSL uses the
public-and-private key encryption system, which includes the use of a digital certificate. SSL is used for
other applications than SSH, for example, OpenFlow.
spoofing
Hijacking a server’s IP address or hostname so that requests to the server are redirected to another
server. Certificate validation is used to detect and prevent this.
standard mode
Use ESRP standard mode if your network contains switches running ExtremeWare and switches
running ExtremeXOS, both participating in ESRP.
STP
Spanning Tree Protocol. STP is a protocol, defined in IEEE 802.1d, used to eliminate redundant data
paths and to increase network efficiency. STP allows a network to have a topology that contains
physical loops; it operates in bridges and switches. STP opens certain paths to create a tree topology,
thereby preventing packets from looping endlessly on the network. To establish path redundancy, STP
creates a tree that spans all of the switches in an extended network, forcing redundant paths into a
standby, or blocked, state. STP allows only one active path at a time between any two network devices
(this prevents the loops) but establishes the redundant links as a backup if the initial link should fail. If
STP costs change, or if one network segment in the STP becomes unreachable, the spanning tree
algorithm reconfigures the STP topology and re-establishes the link by activating the standby path.
STPD
Spanning Tree Domain. An STPD is an STP instance that contains one or more VLANs. The switch can
run multiple STPDs, and each STPD has its own root bridge and active path. In the Extreme Networks
implementation of STPD, each domain has a carrier VLAN (for carrying STP information) and one or
more protected VLANs (for carrying the data).
STPD mode
The mode of operation for the STPD. The two modes of operation are:
• 802.1d—Compatible with legacy STP and other devices using the IEEE 802.1d standard.
• 802.1w—Compatible with Rapid Spanning Tree (RSTP).
stub areas
In OSPF, a stub area is connected to only one other area (which can be the backbone area). External
route information is not distributed to stub areas.
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subnet mask
See netmask.
subnets
Portions of networks that share the same common address format. A subnet in a TCP/IP network uses
the same first three sets of numbers (such as 198.63.45.xxx), leaving the fourth set to identify devices
on the subnet. A subnet can be used to increase the bandwidth on the network by breaking the
network up into segments.
superloop
In EAPS, a superloop occurs if the common link between two EAPS domains goes down and the master
nodes of both domains enter the failed state putting their respective secondary ports into the
forwarding state. If there is a data VLAN spanning both EAPS domains, this action forms a loop
between the EAPS domains.
SVP
SpectraLink Voice Protocol, a protocol developed by SpectraLink to be implemented on access points
to facilitate voice prioritization over an 802.11 wireless LAN that will carry voice packets from
SpectraLink wireless telephones.
syslog
A protocol used for the transmission of event notification messages across networks, originally
developed on the University of California Berkeley Software Distribution (BSD) TCP/IP system
implementations, and now embedded in many other operating systems and networked devices. A
device generates a messages, a relay receives and forwards the messages, and a collector (a syslog
server) receives the messages without relaying them.
Syslog uses the user datagram protocol (UDP) as its underlying transport layer mechanism. The UDP
port that has been assigned to syslog is 514. (RFC 3164)
system health check
The primary responsibility of the system health checker is to monitor and poll error registers. In
addition, the system health checker can be enabled to periodically send diagnostic packets. System
health check errors are reported to the syslog.
T
TACACS+
Terminal Access Controller Access Control System. Often run on UNIX systems, the TACAS+ protocol
provides access control for routers, network access servers, and other networked computing devices via
one or more centralized servers. TACACS+ provides separate authentication, authorization, and
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accounting services. User passwords are administered in a central database rather than in individual
routers, providing easily scalable network security solutions.
tagged VLAN
You identify packets as belonging to the same tagged VLAN by putting a value into the 12-bit (4 octet)
VLAN ID field that is part of the IEEE 802.1Q field of the header. Using this 12-bit field, you can configure
up to 4096 individual VLAN addresses (usually some are reserved for system VLANs such as
management and default VLANs); these tagged VLANs can exist across multiple devices. The tagged
VLAN can be associated with both tagged and untagged ports.
TCN
Topology change notification. The TCN is a timer used in RSTP that signals a change in the topology of
the network.
TCP / IP
Transmission Control Protocol. Together with Internet Protocol (IP), TCP is one of the core protocols
underlying the Internet. The two protocols are usually referred to as a group, by the term TCP/IP. TCP
provides a reliable connection, which means that each end of the session is guaranteed to receive all of
the data transmitted by the other end of the connection, in the same order that it was originally
transmitted without receiving duplicates.
TFTP
Trivial File Transfer Protocol. TFTP is an Internet utility used to transfer files, which does not provide
security or directory listing. It relies on UDP.
TKIP
Temporal Key Integrity Protocol (TKIP) is an enhancement to the WEP encryption technique that uses a
set of algorithms that rotates the session keys. The protocol's enhanced encryption includes a perpacket key mixing function, a message integrity check (MIC), an extended initialization vector (IV) with
sequencing rules, and a re-keying mechanism. The encryption keys are changed (re-keyed)
automatically and authenticated between devices after the re-key interval (either a specified period of
time, or after a specified number of packets has been transmitted).
TLS
Transport Layer Security. See SSL
ToS / DSCP
ToS (Type of Service) / DSCP (Diffserv Codepoint). The ToS/DSCP box contained in the IP header of a
frame is used by applications to indicate the priority and Quality of Service for each frame. The level of
service is determined by a set of service parameters which provide a three way trade-off between low-
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delay, high-reliability, and high-throughput. The use of service parameters may increase the cost of
service.
transit node
In EAPS, the transit node is a switch, or node, that is not designated a master in the EAPS domain ring.
TRILL
Transparent Interconnection of Lots of Links. TRILL allows for improved scaling of data center servers
and virtual machine interconnections by combining bridged networks with network topology control
and routing management.
truststore
A repository containing trusted certificates, used to validate an incoming certificate. A truststore usually
contains CA certificates, which represent certificate authorities that are trusted to sign certificates, and
can also contain copies of server or client certificates that are to be trusted when seen.
TSN
Transition Security Network. A subset of Robust Security Network (RSN), which provides an enhanced
security solution for legacy hardware. The Wi-Fi Alliance has adopted a solution called Wireless
Protected Access (WPA), based on TSN. RSN and TSN both specify IEEE 802.1x authentication with
Extensible Authentication Protocol (EAP).
tunnelling
Tunnelling (or encapsulation) is a technology that enables one network to send its data via another
network's connections. Tunnelling works by encapsulating packets of a network protocol within packets
carried by the second network. The receiving device then decapsulates the packets and forwards them
in their original format.
U
U-NII
Unlicensed National Information Infrastructure. Designated to provide short-range, high-speed wireless
networking communication at low cost, U-NII consists of three frequency bands of 100 MHz each in the
5 GHz band: 5.15-5.25GHz (for indoor use only), 5.25-5.35 GHz and 5.725-5.825GHz. The three
frequency bands were set aside by the FCC in 1997 initially to help schools connect to the Internet
without the need for hard wiring. U-NII devices do not require licensing.
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UDP
User Datagram Protocol. This is an efficient but unreliable, connectionless protocol that is layered over
IP (as is TCP). Application programs must supplement the protocol to provide error processing and
retransmitting data. UDP is an OSI Layer 4 protocol.
unicast
A unicast packet is communication between a single sender and a single receiver over a network.
untagged VLAN
A VLAN remains untagged unless you specifically configure the IEEE 802.1Q value on the packet. A port
cannot belong to more than one untagged VLAN using the same protocol.
USM
User-based security model. In SNMPv3, USM uses the traditional SNMP concept of user names to
associate with security levels to support secure network management.
V
virtual router
In the Extreme Networks implementations, virtual routers allow a single physical switch to be split into
multiple virtual routers. Each virtual router has its own IP address and maintains a separate logical
forwarding table. Each virtual router also serves as a configuration domain. The identity of the virtual
router you are working in currently displays in the prompt line of the CLI. The virtual routers discussed in
relation to Extreme Networks switches themselves are not the same as the virtual router in VRRP.
In VRRP, the virtual router is identified by a virtual router (VRID) and an IP address. A router running
VRRP can participate in one or more virtual routers. The VRRP virtual router spans more than one
physical router, which allows multiple routers to provide redundant services to users.
VEPA
Virtual Ethernet Port Aggregator. This is a Virtual Machine (VM) server feature that works with the
ExtremeXOS Direct Attach Feature to support communications between VMs.
virtual link
In OSPF, when a new area is introduced that does not have a direct physical attachment to the
backbone, a virtual link is used. Virtual links are also used to repair a discontiguous backbone area.
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virtual router
In the Extreme Networks implementations, virtual routers allow a single physical switch to be split into
multiple virtual routers. Each virtual router has its own IP address and maintains a separate logical
forwarding table. Each virtual router also serves as a configuration domain. The identity of the virtual
router you are working in currently displays in the prompt line of the CLI. The virtual routers discussed in
relation to Extreme Networks switches themselves are not the same as the virtual router in VRRP.
In VRRP, the virtual router is identified by a virtual router (VRID) and an IP address. A router running
VRRP can participate in one or more virtual routers. The VRRP virtual router spans more than one
physical router, which allows multiple routers to provide redundant services to users.
virtual router MAC address
In VRRP, RFC 2338 assigns a static MAC address for the first five octets of the VRRP virtual router. These
octets are set to 00-00-5E-00-01. When you configure the VRRP VRID, the last octet of the MAC
address is dynamically assigned the VRID number.
VLAN
Virtual LAN. The term VLAN is used to refer to a collection of devices that communicate as if they are
on the same physical LAN. Any set of ports (including all ports on the switch) is considered a VLAN.
LAN segments are not restricted by the hardware that physically connects them. The segments are
defined by flexible user groups you create with the CLI.
VLSM
Variable-length subnet masks. In OSPF, VLSMs provide subnets of different sizes within a single IP
block.
VM
Virtual Machine. A VM is a logical machine that runs on a VM server, which can host multiple VMs.
VMAN
Virtual MAN. In ExtremeXOS software, VMANs are a bi-directional virtual data connection that creates a
private path through the public network. One VMAN is completely isolated from other VMANs; the
encapsulation allows the VMAN traffic to be switched over Layer 2 infrastructure. You implement VMAN
using an additional 892.1Q tag and a configurable EtherType; this feature is also known as Q-in-Q
switching.
VNS
Virtual Network Services. An Extreme Networks-specific technique that provides a means of mapping
wireless networks to a wired topology.
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VoIP
Voice over Internet Protocol is an Internet telephony technique. With VoIP, a voice transmission is cut
into multiple packets, takes the most efficient path along the Internet, and is reassembled when it
reaches the destination.
VPN
Virtual private network. A VPN is a private network that uses the public network (Internet) to connect
remote sites and users. The VPN uses virtual connections routed through the Internet from a private
network to remote sites or users. There are different kinds of VPNs, which all serve this purpose. VPNs
also enhance security.
VR-Control
This virtual router (VR) is part of the embedded system in Extreme Networks switches. VR-Control is
used for internal communications between all the modules and subsystems in the switch. It has no
ports, and you cannot assign any ports to it. It also cannot be associated with VLANs or routing
protocols. (Referred to as VR-1 in earlier ExtremeXOS software versions.)
VR-Default
This VR is part of the embedded system in Extreme Networks switches. VR-Default is the default VR on
the system. All data ports in the switch are assigned to this VR by default; you can add and delete ports
from this VR. Likewise, VR-Default contains the default VLAN. Although you cannot delete the default
VLAN from VR-Default, you can add and delete any user-created VLANs. One instance of each routing
protocol is spawned for this VR, and they cannot be deleted. (Referred to as VR-2 in earlier
ExtremeXOS software versions.)
VR-Mgmt
This VR is part of the embedded system in Extreme Networks switches. VR-Mgmt enables remote
management stations to access the switch through Telnet, SSH, or SNMP sessions; and it owns the
management port. The management port cannot be deleted from this VR, and no other ports can be
added. The Mgmt VLAN is created VR-Mgmt, and it cannot be deleted; you cannot add or delete any
other VLANs or any routing protocols to this VR. (Referred to as VR-0 in earlier ExtremeXOS software
versions.)
VRID
In VRRP, the VRID identifies the VRRP virtual router. Each VRRP virtual router is given a unique VRID. All
the VRRP routers that participate in the VRRP virtual router are assigned the same VRID.
VRRP
Virtual Router Redundancy Protocol. VRRP specifies an election protocol that dynamically assigns
responsibility for a virtual router to one of the VRRP routers on a LAN. The VRRP router controlling the
IP address(es) associated with a virtual router is called the master router, and forwards packets sent to
these IP addresses. The election process provides dynamic failover in the forwarding responsibility
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should the master router become unavailable. In case the master router fails, the virtual IP address is
mapped to a backup router's IP address; this backup becomes the master router. This allows any of the
virtual router IP addresses on the LAN to be used as the default first-hop router by end-hosts. The
advantage gained from using VRRP is a higher availability default path without requiring configuration
of dynamic routing or router discovery protocols on every host. VRRP is defined in RFC 2338.
VRRP router
Any router that is running VRRP. A VRRP router can participate in one or more virtual routers with
VRRP; a VRRP router can be a backup router for one or more master routers.
VSA
Vendor Specific Attribute. An attribute for a RADIUS server defined by the manufacturer.(compared to
the RADIUS attributes defined in the original RADIUS protocol RFC 2865). A VSA attribute is defined in
order that it can be returned from the RADIUS server in the Access Granted packet to the Radius Client.
W
walled garden
A restricted subset of network content that wireless devices can access.
WEP
Wired Equivalent Privacy. A security protocol for wireless local area networks (WLANs) defined in the
802.11b standard. WEP aims to provide security by encrypting data over radio waves so that it is
protected as it is transmitted from one end point to another.
WINS
Windows Internet Naming Service. A system that determines the IP address associated with a particular
network computer, called name resolution. WINS supports network client and server computers running
Windows and can provide name resolution for other computers with special arrangements. WINS
supports dynamic addressing (DHCP) by maintaining a distributed database that is automatically
updated with the names of computers currently available and the IP address assigned to each one.
DNS is an alternative system for name resolution suitable for network computers with fixed IP
addresses.
WLAN
Wireless Local Area Network.
WMM
Wi-Fi Multimedia (WMM), a Wi-Fi Alliance certified standard that provides multimedia enhancements
for Wi-Fi networks that improve the user experience for audio, video, and voice applications. This
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standard is compliant with the IEEE 802.11e Quality of Service extensions for 802.11 networks. WMM
provides prioritized media access by shortening the time between transmitting packets for higher
priority traffic. WMM is based on the Enhanced Distributed Channel Access (EDCA) method.
WPA
Wireless Protected Access, or Wi-Fi Protected Access is a security solution adopted by the Wi-Fi
Alliance that adds authentication to WEP's basic encryption. For authentication, WPA specifies IEEE
802.1x authentication with Extensible Authentication Protocol (EAP). For encryption, WPA uses the
Temporal Key Integrity Protocol (TKIP) mechanism, which shares a starting key between devices, and
then changes their encryption key for every packet. Certificate Authentication (CA) can also be used.
Also part of the encryption mechanism are 802.1x for dynamic key distribution and Message Integrity
Check (MIC) a.k.a. Michael.
WPA requires that all computers and devices have WPA software.
WPA-PSK
Wi-Fi Protected Access with Pre-Shared Key, a special mode of WPA for users without an enterprise
authentication server. Instead, for authentication, a Pre-Shared Key is used. The PSK is a shared secret
(passphrase) that must be entered in both the AP or router and the WPA clients.
This pre-shared key should be a random sequence of characters at least 20 characters long or
hexadecimal digits (numbers 0-9 and letters A-F) at least 24 hexadecimal digits long. After the initial
shared secret, the Temporal Key Integrity Protocol (TKIP) handles the encryption and automatic rekeying.
X
XENPAK
Pluggable optics that contain a 10 Gigabit Ethernet module. The XENPAKs conform to the IEEE 802.3ae
standard.
XNV
Extreme Network Virtualization. This ExtremeXOS feature enables the software to support VM port
movement, port configuration, and inventory on network switches.
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