managing_x25gateway

managing_x25gateway
Managing the Xyplex X.25 Gateway
X.25 Gateway Software
Version 1.3
February 1994
Xyplex, Incorporated
295 Foster Street
Littleton, MA 01460
451-0010B
Effective Pages
This guide 149 contains pages, including the following:
Issues: Original
Date: February 1994
Pages
Issue
i through xi
1-1 through 1-11
2-1 through 2-22
3-1 through 3-22
4-1 through 4-29
5-1 through 5-30
6-1 through 6-10
A-1 through A-2
B-1
C-1 through C-3
D-1 through D-2
Index-1 through Index-6
Original
Original
Original
Original
Original
Original
Original
Original
Original
Original
Original
Original
Caution
This equipment generates, uses, and can radiate radio frequency energy and if not
installed and used in accordance with the instructions manual, may cause interference to
radio communications. It has been tested and found to comply with the limits for a Class A
computing device pursuant to Subpart J of Part 15 of FCC Rules, which are designed to
provide reasonable protection against such interference in a commercial environment.
Operation of this equipment in a residential area is likely to cause interference in which
case the user at his own expense will be required to take whatever measures may be
required to correct the interference.
Shielded cables should be used with this unit to insure compliance with the Class A unit.
The hardware and software described in this document are subject to change without notice.
The information in this document is subject to change without notice and should not be construed
as a commitment by Xyplex. Xyplex reserves the right to revise this publication without
obligation to provide notification of such revisions. While reasonable precautions have been
taken, Xyplex assumes no responsibility for errors that may appear in this document.
No part of this publication may be copied or reproduced in any form or by any means
without the prior written consent of Xyplex, Inc.
Xyplex, MAXserver, and LANbus are registered trademarks of Xyplex, Inc.
MAXman is a trademark of Xyplex, Inc.
DEC, VAX, RCP, and DECserver are trademarks of Digital Equipment Corporation.
LAT is a registered trademark of Digital Equipment Corporation.
Ethernet is a trademark of the Xerox corporation.
UNIX is a registered trademark of AT&T Bell Laboratories.
Copyright © 1994 by Xyplex, Inc. Printed in the USA.
2
0010
Table of Contents
Preface
Page
Chapter 1 - Introduction to the X.25 Gateway
About Packet-Switched Networks (PSNs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3
About the X.25 Standards...................................................................................13
The DTE/DCE Interface..........................................................................14
The X.25 Levels of Procedure.....................................................................15
X.25 Gateway Support for X.25 Features..................................................................15
Virtual Circuits....................................................................................15
PAD Functionality................................................................................16
User Facilities.....................................................................................17
Communications Server Features........................................................................17
Virtual Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 7
Local Services......................................................................................17
Point-to-Point Protocol Support...................................................................20
X.25 Gateway Hardware...................................................................................21
LAN and X.25 interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1
The External Clock................................................................................22
Chapter 2 - Configuring the X.25 Gateway for Basic Use
Establish the LAN Connection to the X.25 Gateway.....................................................24
Specify Communications Server Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 7
Viewing and Changing the X.25 Gateway Databases.........................................27
Enable the X.25 Protocol on the 6800 X.25 Gateway.............................................27
Enable the Point-to-Point Protocol at PPP Sites................................................28
Specify Internet Characteristics for Telnet Implementations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 8
Enable Accounting Features to Log X.25 Session Information...............................29
Specify X.25 Characteristics...............................................................................30
X.25 Gateway Server Management Characteristics...........................................30
Level 2 Parameters and Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2
Level 3 Parameters and Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 4
Initialize the X.25 Gateway................................................................................43
0010
3
Chapter 3 - Sending and Receiving Calls
Making Calls to the PSN...................................................................................45
Creating a LAT or Telnet Service...............................................................46
Calling an X.25 Address from the PAD Prompt................................................47
Creating a Local Service that Calls an X.25 Address..........................................48
Assigning an X.25 Address to a Virtual Port...................................................49
Changing the Outbound PAD Profile ...........................................................50
Viewing LAT and Telnet Services..............................................................50
Calling the LAN from the PSN............................................................................51
About the Listen Address..........................................................................51
About the X.25 Port Connect Action Type........................................................54
Changing the Inbound PAD Profile in an X.25 Service.......................................62
Viewing X.25 Services............................................................................62
Using Remote Profiles in Local Services................................................................62
Remote Profiles in LAT and Telnet Services..................................................63
Remote Profiles in X.25 Services................................................................63
Using Remote Profiles in a Large Network....................................................64
Making Calls to a Remote Printer........................................................................64
Setting Characteristics for Virtual Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4
Creating the Local Service on the X.25 Gateway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 4
Creating the Local Service on the Remote X.25 Gateway......................................65
Example of a Call to a Remote Printer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 5
Chapter 4 - X.3 PAD Parameters and Profiles
The X.25 Gateway PAD Profiles..........................................................................68
PAD Parameter Summary................................................................................70
Changing Local Profiles and Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2
Using PAD Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2
Using Xyplex Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 3
Using Local Services to Change Local PAD Profiles..........................................74
Changing Remote Profiles and Parameters............................................................74
Using PAD Commands...........................................................................75
Using Xyplex Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5
Using Local Services to Change Remote PAD Profiles and Parameters . . . . . . . . . . . . . . . . . . . 7 6
PAD Parameters............................................................................................77
4
0010
Chapter 5 - Using the X.28 PAD Commands
Obtaining the PAD Prompt................................................................................95
Connecting to the PAD from a Virtual Port.....................................................95
Returning the PAD to Command State During a Virtual Call . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 5
Entering PAD Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 6
CALL.........................................................................................................97
CLR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 9
FACILITIES.................................................................................................100
FULL.........................................................................................................101
HALF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 2
HELP.........................................................................................................103
INTERRUPT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 0 4
LISTEN......................................................................................................105
PAR?.........................................................................................................106
PROF.........................................................................................................107
RESET.......................................................................................................109
RICLR........................................................................................................110
RPAR?.......................................................................................................111
RPROF.......................................................................................................112
RSET.........................................................................................................114
RSET?........................................................................................................115
SET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 6
SET?..........................................................................................................117
STATUS.....................................................................................................118
TABS.........................................................................................................119
X.29 PAD Service Signals.................................................................................120
Chapter 6 - Basic Problem Solving
Status problems with the X.25 Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 4
Level 1 Problems...................................................................................124
Level 2 and Level 3 Problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 6
Conditions that Prevent Virtual Calls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 7
Problems Caused by Incorrect Parameter Settings.....................................................132
Appendix A - Status and Error Messages
Appendix B - ASCII Values for International Alphabet Number 5
Appendix C - PAD Profile Tables
Appendix D - Features in TCP/IP-LAT Software V5.1 That Do Not Exist in
the X.25 Gateway V1.3
0010
5
Index
Table of Figures
Figure
1-1
1-2
1-3
1-4
1-5
1-6
An X.25 Network.....................................................................................12
The X.25 Standard for the DTE/DCE Interface...................................................14
A Representation of a Virtual Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 6
LAT and Telnet Services...........................................................................18
An X.25 Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 9
A PPP Connection on the X.25 Gateway...........................................................20
2-1
2-2
2-3
2-4
2-5
2-6
2-8
Logging On To the X.25 Gateway . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 4
A typical Show Server Display a System Initialization Time..................................26
An X.25 Characteristics Display...................................................................31
Default Settings for Level Characteristics........................................................33
Default Settings for Virtual Circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 5
The Show X.25 Status Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3
Sample LCN Ranges for Virtual Circuits.........................................................44
3-1
3-2
3-3
3-4
3-5
3-6
3-7
3-8
3-9
3-10
3-11
3-12
A LAT Service that Returns the PAD Prompt.....................................................47
A Telnet Service that Calls an X.25 Address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 9
A Sample Show Service Local Summary Display................................................50
A Default Listen Address...........................................................................51
Listen Addresses on an X.25 Gateway.............................................................52
Multiple Listen Addresses..........................................................................53
Two Nondefault Listen Addresses.................................................................54
A Default Connect Action Type.....................................................................55
Connect Action Type None..........................................................................57
Connect Action Type Autoconnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 9
Connect Action Type Userdata.....................................................................61
A Show Service Local X.25 Summary Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 2
4-1
4-2
4-3
4-4
An X.25 Server Characteristics Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 9
An X.25 Port Characteristics Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 9
An X.25 Profile Display for the Profile Hardcopy................................................71
A Sample Alternate Characteristics Display for Port 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 2
6-1
6-2
The Status Lights on a 6625 Card...................................................................125
The Status Indicators on a 6025 Standalone Unit.................................................126
6
0010
Table of Tables
Table
2-1
2-2
2-3
2-4
2-5
2-6
2-7
Xyplex Prompts.......................................................................................25
Level 2 Options and Default Settings..............................................................33
User Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 9
Per-Call Facilities...................................................................................40
DCE Timeouts........................................................................................41
DTE Timeouts........................................................................................41
Level 3 Retry Counters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2
4-1
4-2
X.25 Gateway Profiles...............................................................................68
Default parameter Values for the X.25 Gateway PAD Profiles.................................71
6-1
6-2
Clear Cause Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 8
CCITT Diagnostic Codes............................................................................130
B-1
Decimal and Hexadecimal Values for ASCII Characters......................................136
0010
7
Preface
This manual describes how to manage and use the Xyplex X.25 Gateway. It
explains how to specify the basic X.25 Gateway characteristics and parameters, how
to send and receive virtual calls, and how to use the X.25 gateway PAD. This
manual is for network managers who are responsible for installing and
managing network software.
While this manual explains how the Xyplex X.25 Gateway supports the CCITT X.25
standards, it does not describe the standards in full detail. Refer to the CCITT
standards documentation for complete information about X.25 Standards.
Organization
This manual contains the following chapters:
Chapter 1 Describes the X.25 Gateway and how it supports both the X.25 standards
and the features of a Xyplex Communications Server. This chapter
also contains some introductory information about X.25 networks and
packet-switching technology.
Chapter 2 Describes how to set the minimum number of characteristics on the
X.25 Gateway to make a calls to the PSN and establish a virtual
circuit.
Chapter 3 Explains how to make calls to devices on the PSN from the X.25
Gateway through LAT and Telnet services, and how to configure X.25
Gateway ports to receive calls from the PSN with X.25 services.
Chapter 4 Describes the CCITT standard X.3 PAD profiles and parameters that
the X.25 Gateway supports.
Chapter 5 Describes the CCITT standard X.28 PAD commands that the X25
Gateway supports.
Chapter 6 Describes some common problems, their symptoms, and possible
solutions.
0010
Appendix A
X.25 Gateway Error Messages.
Appendix B
ASCII Table for International Alphabet Number 5 (IA5).
Appendix C
Blank PAD parameter tables.
Appendix D
TCP/IP-LAT V5.1 Communications Server features not supported
on the X.25 Gateway V1.3.
8
Preface
Conventions
Throughout this manual, the word "Enter" means type something and then press
the New Line key, Carriage Return key, or Enter key; for example, "Enter the
CONNECT command" means type the word "CONNECT" and then press the New
Line, Carriage Return, or Enter key.
This manual also uses the following conventions:
COMMAND
KEYWORD variable
Where
Means
COMMAND
You must enter the command, or its accepted abbreviation, as
shown.
KEYWORD
You must enter a keyword, or its accepted abbreviation, as shown.
variable
You must enter a variable such as a host name, file name, or
character string.
Sometimes the manual shows this:
[COMMAND | COMMAND] or [KEYWORD | KEYWORD] or [variable | variable]
You must enter one of the commands, keywords or variables. Do not enter the
braces; they simply show the choices. The bar | separates the choices.
Additionally, this manual uses certain symbols in special ways:
Symbol
Means
Press the New Line, Carriage Return <CR>, or Enter key on your
terminal's keyboard.
Xyplex>
This is the Xyplex MAXserver prompt at Secure and Nonprivileged
ports on the X.25 Gateway.
Xyplex>>
This is the Xyplex MAXserver prompt at Privileged ports on the X.25
Gateway.
*
This is the default PAD prompt on the Xyplex X.25 Gateway.
In examples, this manual uses
This typeface to show your entry and X.25 Gateway responses.
0010
9
Preface
Related Documentation
The Xyplex X.25 Gateway Commands Reference Guide
This is a companion manual to Managing the Xyplex X.25 Gateway. It includes all
the DEFINE/SET X25 commands, as well as the DEFINE/SET SERVICE
commands that create local services.
V1.3 of the X.25 Gateway incorporates V5.1 of TCP/IP-LAT software. If you do not
have the V5.1 TCP/IP-LAT documentation set, Xyplex recommends that you obtain
a copy of this documentation. It describes the many features in V5.1 that are not
described in the V4.0 documentation set, including the Point-to-Point protocol
(PPP), Verbose Accounting, the UNIX daemons, the UNIX-Like Interface (ULI),
and Nested Menus. To order a copy of the V5.1 TCP/IP-LAT documentation set,
call your Xyplex sales representative.
The following manuals provide information about the V5.1 TCP/IP-LAT
Communications Server:
The Xyplex TCP/IP-LAT Software Management Guide
This manual describes the configuration, setup, and management of the TCP/IP
LAT Communications Server package, supplied by Xyplex, Inc. This manual is
written for network managers, and terminal server, UNIX® , and VAX system
managers.
The TCP/IP-LAT Commands Reference Guide
This manual includes all of the Xyplex TCP/IP-LAT Communications Server
commands.
Xyplex includes the following documentation with X.25 Gateway Hardware. These
manuals explain how to unpack, set-up, and load software onto an X.25 Gateway
Getting Started with the MAXserver 6025 X.25 Gateway
Getting Started with the MAXserver 6625 X.25 Gateway
Getting Started with the MAXserver 6800 Remote Router Card
Getting Started with the Network 9000 WAN Processor 6800
If you have questions about this product...
At your convenience, please forward these to Xyplex at the following addresses:
Internet Mail:
[email protected]
United States Mail:
Xyplex, Inc.
295 Foster Street
10
0010
Preface
Littleton, MA 01460
Attn: Manager, Customer Support
If you have comments about this guide...
To help us in our effort to improve the quality, usefulness, and technical accuracy of the
product documentation you receive, Xyplex is interested in any comments or suggestions
that you have about this guide, or any technical corrections that you believe should be made.
At your convenience, please forward these to Xyplex at the following addresses:
Internet Mail:
[email protected]
United States Mail:
Xyplex, Inc.
295 Foster Street
Littleton, MA 01460
Attn: Manager, Technical Documentation
Software Upgrade Information
For information on software upgrades contact your local representative, or call Xyplex
directly at
In the United States:
In Europe:
In Asia:
(800) 338-5316
+44 81 759-1633
+65 336-0431
End of Preface
0010
11
Chapter 1
Introduction to the X.25 Gateway
The Xyplex ® X.25 Gateway links devices on anEthernet™ local area network
(LAN) to a packet-switched network (PSN). The X.25 Gateway converts data from
a TCP/IP, LAT® , SLIP, PPP, or TN3270 session into X.25 packets and converts
X.25 packets into data for the LAN protocol. With the X.25 Gateway, LAN users can
gain access to remote X.25 resources such as terminals, printers, hosts, and
databases, and X.25 network users can gain access to LAN resources such as
terminals, printers, UNIX® hosts, VAX™ hosts, and IBM hosts.
Figure 1-1 shows a sample X.25 network with two X.25 Gateway cards in a chassis
connecting devices on the LAN to the PSN.
LAN
Terminals and
Printers
X.25
PAD
UNIX Host
X.25 Gateway modulesin a
Network 9000
Intra-Networking Hub
2
X.25 Host
HostA
PSN
VAX/VMS
Host
PPP or SLIP
ULTRIX
HOST
PC with
PAD
Figure 1-1. An X.25 Network
0010
12
Introduction
From the LAN, a user on the ULTRIX host in Figure 1-1 can call HostA, and print a
document from a printer on HostA. A user on the VAX/VMS host can exchange
electronic mail through the X.25 Gateway with a user on HostB, another X.25
compatible host on the network.
The X.25 Gateway supports X.25 standards for communication across a PSN, and
offers the features of a Xyplex terminal server for communication on the LAN.
This chapter gives an overview of PSNs, and describes how the X.25 Gateway
supports both LAN connections and the X.25 protocol for PSNs. This chapter
includes these topics:
•
About Packet Switched Networks (PSNs)
•
About the X.25 Standards
•
X.25 Gateway Support for X.25 Features
•
X.25 Gateway Support for Communications Server Features
•
X.25 Gateway Hardware
About Packet Switched Networks (PSNs)
A packet-switched network (PSN) transfers information from one destination to
another in discrete entities called packets. A typical PSN consists of Data Circuit
Equipment (DCEs) and Packet Switching Exchanges (PSEs). The DCEs provide
the interface between the user and the network. The PSEs forward the packets
around the network to the DCEs. The packets can contain user data, such as files,
and control information, such as the destination address.
A PSN can route many packets from different users over shared transmission
facilities to different addresses on the network. These transmission facilities may
vary among PSNs, but the differences are transparent to end-users. Users are
mainly concerned that the data they send and receive is timely, error-free, and
arrives in the correct order. PSNs do share some common characteristics,
however, regardless of the nature of their facilities.
About the X.25 Standards
One characteristic that is common to all PSNs is the requirement for an interface
between the user's equipment and the network. The CCITT, an international
standards organization, has defined standards for the user/network interface in a
PSN called Recommendation X.25. The X.25 standards are internationally
recognized, and different vendors whose products conform to them can use a PSN
as a common carrier.
0010
13
Introduction
The DTE/DCE Interface
In the X.25 standard, the user/network interface is called the DTE/DCE interface.
The Data Terminal Equipment (DTE) is the user's system, and the Data Circuit
Equipment (DCE) is the port into the network. Figure 1-2 represents a PSN with
several DTE/DCE interfaces.
DTE
DCE
DTE
DCE
PSN
PSN
X.25
DTE
DCE
X.25
DCE
DTE
Figure 1-2. The X.25 Standard for the DTE/DCE Interface
Two types of data terminal equipment exist: packet-mode DTEs and start-stop
mode DTEs. Packet-mode DTEs are host computer systems that have implemented
software that supports the X.25 standard and can send and receive packets. Startstop mode DTEs are asynchronous devices such as terminals and printers that
send and receive asynchronous characters.
A computer or an asynchronous device connected to a PSN acts as a DTE because a
DCE is a component of the network itself. If you have a private network, however,
you may have some computers acting as DTEs and some acting as DCEs. The X.25
Gateway link can emulate a DTE or a DCE, although most implementations
require that the X.25 Gateway link emulate a DTE.
14
0010
Introduction
The X.25 Levels of Procedure
Recommendation X.25 defines the interaction between a DTE and a DCE in three
separate levels of procedure. The X.25 Gateway supports each of these levels:
Level 1
Level 1, the physical layer, defines the mechanical protocol to establish, maintain,
and terminate the electrical network connections. These connections transmit
digitized signals between network nodes. The unit of data transferred at this level
is a bit.
Level 2
Level 2, the frame layer, provides an error detection and correction mechanism
over the physical layer. The unit of data transferred at this level is a frame.
Level 3
Level 3, the packet layer, defines packet formats and manages the exchange of
packets, containing control information and user data, between the DTE and the
DCE. The unit of data transferred at this level is a packet.
Each of these levels provides services to the level above, interfaces with the level
below, and conducts peer protocol with its opposite DTE/DCE interface across the
PSN. In addition, the three X.25 levels form the first three layers of the
international standards organization (ISO) model for open systems
interconnection (OSI).
X.25 Gateway Support for X.25 Features
The X.25 standard defines several user features at Level 3, the packet layer, where
users gain access to X.25 though upper-level processes. The X.25 Gateway supports
these features, described in the following sections: Virtual Circuits, PAD
functionality, and User Facilities.
Virtual Circuits
A virtual circuit is a logical association between two DTEs. It does not represent a
physical connection, but rather a logical communication path across the PSN.
Figure 1-3 represents a virtual circuit between a Xyplex X.25 Gateway and an X.25
host.
0010
15
Introduction
X
virtual circuit
X
PSN
6625 X.25
Gateway
X.25 Host
Figure 1-3. A Representation of a Virtual Circuit
The X.25 Gateway supports the two CCITT standard types of virtual circuits:
permanent virtual circuits (PVCs) and switched virtual circuits (SVCs). You can
establish up to 80 virtual circuits, in any combination of PVCs and SVCs, on the
X.25 Gateway.
A permanent virtual circuit is a permanent association between two DTEs that you
establish when you subscribe to the PSN. The PSN administration allocates
certain resources to this type of virtual circuit for an agreed upon period of time. A
PVC is similar to a private telephone line, as it does not require a user to set up or
clear calls. The connection is always active and ready to transfer data.
A switched virtual circuit is a temporary association between two DTEs that you
establish by sending a call request packet to the PSN through the DTE. The calling
DTE receives a response which indicates whether or not the called DTE can accept
the call. If the called DTE agrees, the PSN establishes a virtual circuit between
them. Either DTE can clear the SVC, after which it no longer exists. An SVC is
similar to a dial-up telephone line, as a user must set up and clear calls. The
connection is only active when both sides agree to take the call, and only then can
you transfer data across the connection.
PAD Functionality
Start-stop mode DTEs such as terminals and printers that do not support the X.25
protocol require software modules called packet assemblers/disassemblers or
PADs. A PAD provides an interface between the start-stop mode DTE and the PSN.
The PAD converts the asynchronous data to X.25 packets that can travel through the
links in a PSN. The PAD can also convert the X.25 packets back into
asynchronous data for the start-stop mode DTE. The X.25 Gateway provides PAD
functionality, and supports the CCITT recommendations that apply to PADs:
X.28 PAD commands
X.3 PAD parameters
X.29 PAD service signals
16
0010
Introduction
Chapter 4, PAD Profiles and Parameters, describes the X.25 Gateway support for the
PAD in detail. Chapter 5, PAD Commands and Service Signals, describes the PAD
commands in detail.
User Facilities
X.25 standard user facilities allow you to customize the PSN connection. They
include reverse charging, fast select acceptance, and nondefault sizes for packets
and frames. The X.25 Gateway supports many of these facilities.
You select user facilities at subscription time, so that the PSN administration can
allocate resources for them and charge for them. The X.25 Gateway supports user
facilities for all ports or on a per-port basis for individual calls. Not all PSNs
support all X.25 standard facilities. Chapter 2 lists the X.25 user facilities that the
X.25 Gateway supports.
Communications Server Features
The X.25 Gateway supports many of the features and protocols of a Xyplex TCP/IPLAT Communications Server. These include the LAT, Telnet, TN3270, SLIP,
CSLIP, and Point-to-Point (PPP) protocols, as well as local services, and security
features including Kerberos. See version 5.1 of the TCP/IP-LAT Software
Management Guide for complete descriptions of these features. (See Appendix D of
this manual for information about the V5.1 TCP/IP-LAT features that do not apply
to the X.25 Gateway.)
Virtual ports
Virtual ports provide the interface between the LAN and the PSN. The X.25
Gateway provides 80 virtual ports where you can make connections to and from the
PSN. You make connections to X.25 Gateway virtual ports through local services
on the terminal server.
Local Services
Local services provide access to virtual ports for calls from the LAN and calls from
the PSN. Virtual ports can share local services, and a local service can apply to a
range of virtual ports. LAT and Telnet services provide connections from the LAN
to the X.25 Gateway PAD, and X.25 services provide connections from the PSN to the
X.25 Gateway command interface. Chapter 3, Sending and Receiving Calls,
describes how to create local services.
0010
17
Introduction
The X.25 Gateway can support up to 80 local services. Figure 1-4 represents a LAT
and a Telnet service, which direct outbound calls to destinations on the PSN.
Figure 1-5 represents an X.25 service, which directs inbound calls to destinations
on the LAN.
Remote X.25
Gateway
LAN
02
X.25 Gateway
Virtual ports
DEV.SUN.COM
02
.
.
..
..
..
.
.
51
52
53
53
54
55
.
.
.
.
.
.
81
81
PSN
Remote PAD
LAT and Telnet
Services
FinanceVAX
Figure 1-4. LAT and Telnet Services
In Figure 1-4, a Telnet service directs a call from DEV.SUN.COM to the X.25
Gateway PAD at virtual port 51, and a LAT service directs a call from FinanceVAX
to another X.25 Gateway on the PSN through virtual port 55.
18
0010
Introduction
LAN
X.25 Gateway
Virtual ports
DEV.SUN.COM
02
.
.
..
..
..
.
.
51
52
53
53
54
55
.
.
.
.
.
.
81
PSN
X.25
host
X.25 Service
Remote call
FinanceVAX
Figure 1-5. An X.25 Service
In Figure 1-5, a call from an X.25 host on the PSN arrives at X.25 Gateway virtual
port 52. An X.25 service directs the call to the LAN host DEV.SUN.COM.
0010
19
Introduction
Point-to-Point Protocol Support
The Xyplex implementation of the point-to-point protocol (PPP) allows a personal
computer (PC), a terminal server, or a dialup router to gain access to the Internet
through an X.25 Gateway virtual port. PPP devices establish a virtual circuit on an
X.25 Gateway, enable PPP on the virtual port, then begin sending data to or
receiving data from the TCP/IP host on the remote LAN across the X.25 network.
Figure 1-6 shows a personal computer with a PAD gaining access to an X.25
Gateway on the X.25 network and enabling PPP.
PSN
Personal Computer
with PAD running PPP
2
X.25 Gateway in
Network 9000 chassis
running PPP
UNIX Host
running TCP/IP
LAN
Figure 1-6. A PPP Connection on the X.25 Gateway
Figure 1-6 shows a PC making a connection to a virtual port on an X.25 Gateway
over the PSN. The user on the PC logs on to the Xyplex command interface on the
X.25 Gateway and enables PPP. The user can then return to the command
interface on the PC and begin sending data over PPP to the UNIX host on the remote
network through the X.25 Gateway.
20
0010
Introduction
X.25 Gateway Hardware
The X.25 Gateway software runs on the MAXserver 6625 card, the MAXserver 6025
standalone unit, and the 6800 card. You can mount the 6625 card in a model 4500,
5000, or 5500 MAXserver chassis, or as a Type 1 option with an adapter card in a
Network 9000 Intra-Networking Hub. Refer to the manual Getting Started with the
MAXserver 6625 Gateway for technical specifications and additional information
about the MAXserver 6625 card. Refer to the manual Getting Started with the
MAXserver 6025 X.25 Gateway for technical specifications and additional
information about the 6025 standalone unit.
You can mount the 6800 card in a MAXserver chassis or as a Type 1 option in a
Network 9000 Intra-Networking Hub. The manual Getting Started with the
MAXserver WAN processor 6800 describes how to install the 6800 in a MAXserver
chassis. The manual Getting Started with the Network 9000 WAN Processor 6800
explains how to install the 6800 in a Network 9000 Intra-Networking Hub.
LAN and X.25 Interfaces
The X.25 Gateways provide the following LAN and X.25 interfaces:
Hardware Type
Lan Interface
X.25 Interfaces
Interface to Ethernet 1
6625 Card
Segment A of the Network
9000 Intra-Networking Hub
or
One synchronous V.35, RS422, RS423, RS232,
RS530, or X.21 WAN link
Connection to the LANbus of
the MAXserver chassis
One synchronous V.35 or RS423 WAN link
6025 Standalone
AUI port for interface to the
Unit
LAN
or
One synchronous V.35 or RS232 WAN link
or
One synchronous V.35 or X.21 WAN link
Interface to Ethernet 1
6800 Card
Segment A of the Network
9000 Intra-Networking Hub
or
One synchronous V.35, RS422, RS423, RS232,
RS530, or X.21 WAN link
Connection to the LANbus of
the MAXserver chassis
0010
21
Introduction
You can attach the X.25 interfaces to a communications device or directly to an X.25
host or packet switch. The communications devices include the following:
•
A modem
•
A DSU/CSU
•
A synchronous modem eliminator
If you attach the card or standalone unit to a communications device, use Xyplex
standard straight-through cables. If you attach the card or standalone unit to an
X.25 host or a packet switch, you probably need to use a cross-over cable if the device
is a physical DTE interface, because the default configuration for the X.25 Gateway
is also a DTE.
The External Clock
The X.25 Gateway requires an external clock. If you attach the gateway to a
communications device, this device must supply the clock. If you attach the
Gateway directly to a host or packet switch, the host or switch must supply the clock.
End of Chapter
22
0010
Chapter 2
Configuring the X.25 Gateway for Basic Use
This chapter describes how to define the minimum number of characteristics on the
X.25 Gateway to establish a virtual circuit on the PSN. It assumes that you have
installed the hardware and loaded an X.25 Gateway load image and parameter
file.
This chapter also describes the X.25 Gateway default settings for subscription time
parameters and facilities. You may need to reset these defaults to establish a
virtual circuit, depending on the requirements of the PSN.
To configure the X.25 Gateway for basic use, follow these procedures, described in
this chapter:
0010
•
Establish a Connection to the X.25 Gateway
•
Specify Communications Server Features
•
Specify X.25 Characteristics
•
Initialize the X.25 Gateway
23
Basic Use
Establish a Connection to the X.25 Gateway
The X.25 Gateway has 1 asynchronous port where you can connect a terminal or
modem. This is port 1, the management port. It also supports a logical port where
you make remote connections from a host or other device on the LAN. This is port 0,
the console port. You can log on to the X.25 Gateway through port 0 or port 1. Figure
2-1 shows how different devices make connections through these ports.
VAX/VMS Host
RCP connection to port 0
Unix Host
Telnet connection to port 0
6025 X.25 Gateway
Telnet or RCP connection to port 0
LAN
2
Network 9000
Chassis
Direct or modem Connection to port 1 of a
6625 or 6800 X.25 Gateway in the chassis
Figure 2-1. Logging On To the X.25 Gateway
Figure 2-1 shows that you can connect to port 1, the asynchronous management port,
either with a terminal or through a modem. You can connect to port 0, the console
port, from a remote device through RCP or Telnet. (Each port can support only one
connection.)
To log on to the Xyplex command interface, use one of the following procedures,
depending on the type of connection.
Direct connection: If your terminal is directly connected to port 1, press the <New
Line> or <Return> key until one of the Xyplex login prompts in Table 2-1 appears
on the screen.
24
0010
Basic Use
Connection from a Modem: If you are dialing in through a modem to port 1, use the
same procedure as the direct connection. After dialing in, press the <New Line> or
<Return> key until one of the Xyplex login prompts in Table 2-1 appears on the
screen.
Connection from the Network: If your terminal is connected to another Xyplex
product on the network, use the Xyplex TELNET CONSOLE, TELNET CONNECT,
or REMOTE CONSOLE commands to connect to port 0. Press the <New Line> or
<Return> key until one of the Xyplex prompts in Table 2-1 appears on the screen.
The TCP/IP-LAT Commands Reference Guide describes these commands in
detail.
If your terminal is connected to a UNIX host, you can connect to port 0 through
Telnet with the host-specific Telnet command. If your terminal is connected to a
VAX/VMS host, you can connect to port 0 through RCP with a host-specific
CONNECT command. Press the <New Line> or <Return> key until one of the
Xyplex prompts in Table 2-1 appears on the screen. Consult the host documentation
for information about these commands.
Table 2-1. Xyplex Prompts
Prompt
Action
#
Enter your login password. The default password is access,
but you can define a different password. When you enter the
correct password, the Enter username> prompt appears.
Enter username>
Enter a username. You can enter any username between 1
and 16 characters, or enter <CTRL><Z> to automatically
assign the username Port_x at this port, where x is the port
number. When you enter the username correctly, the
Xyplex> prompt appears.
Xyplex>
This is the default Xyplex command prompt, and it means that
you are logged on to a port. You can now enter Xyplex
commands.
Most X.25 Xyplex commands are Privileged, so enter the SET PRIVILEGE
command at the Xyplex> prompt.
Xyplex> set privilege
0010
25
Basic Use
Enter the privilege password at the Password> prompt, which is system by default.
The password does not echo on the screen when you enter it:
Password>x x x x x
When you enter the correct password, the privileged prompt appears. The double
caret indicates the port is in privileged mode:
Xyplex>>
You can now enter all the commands to configure the X.25 Gateway for basic use.
Once you log on, you can use the SHOW SERVER command to check the version of
software running on the X.25 Gateway. Figure 2-2 is a typical Show Server display.
Xyplex>> show server
MAXx25 V1.3
Address:
ROM 450000 HW 00.02.00 Lat Protocol V5.2 Uptime: 00 00:09:06
Name:
CORP-SERIAL-8
Number:
0
Identification:
Welcome:
Xyplex X25 Gateway
Welcome to the X.25 PAD/Gateway
Circuit Timer:
Console Port:
Inactivity Timer:
Keepalive Timer:
Multicast Timer:
Node Limit:
Textpool Size:
Accounting Entries:
80
0
30
20
30
150
16000
0
Password Limit:
3
Queue Limit:
24
Retransmit Limit:
8
Session Limit:
160
Software:
XYP_X25GATE
Identification Size:
63
Timezone:
00:00
Service Groups: 0
Enabled Characteristics:
Announcements, Broadcast, Dump, Lock Parameter Polling
Figure 2-2. A Typical Show Server Display at System Initialization Time
This display includes the version of Xyplex software on the X.25 Gateway, as well
as the ROM and hardware versions. When the software is up and running,
connect the X.25 Gateway card or standalone unit to the PSN or host system if you
have not already done so.
26
0010
Basic Use
Specify Communications Server Features
The Xyplex X.25 Gateway includes the functionality of a Xyplex Communications
Server as well as a PAD. This functionality supports many optional features and
protocols that you may want to enable when you initially configure the X.25
Gateway. See the TCP/IP-LAT Software Management Guide for more information
about how to enable and modify communications server features and protocols.
While you can enable most features and protocols at any time, this section lists
those features and protocols that you may want to specify or enable when you first set
up the X.25 Gateway. See Appendix D for a list of Communications Server features
and protocols that the X.25 Gateway does not support.
Viewing and Changing the X.25 Gateway Databases
The X.25 Gateway maintains two databases that contain information you specify in
Xyplex commands. One is the operational database and other is the permanent
database. The SET command changes information in the operational database.
The DEFINE command changes information in the permanent database.
Information in the operational database is temporary, and remains current only
until you initialize the X.25 Gateway. While it is current, it overrides the
information in the permanent database. Information in the permanent database is
constant, but only takes effect after you initialize the X.25 Gateway. See The Xyplex
X.25 Gateway Commands Reference Guide for more information about entering
Xyplex commands.
Enable the X.25 Protocol on the 6800 X.25 Gateway
If you have a 6800 X.25 Gateway, and you have loaded the X.25 Gateway load image
for the first time or have upgraded to a V1.3 load image from an earlier version,
you must enable the X.25 protocol. It is not enabled by default on the 6800 as it is on
the 6025 and 6625 platforms.
You need a software password or "key" to enable the X.25 protocol on the 6800 X.25
Gateway. Contact your Xyplex sales representative if you do not have a key. The
following command enables the X.25 protocol:
Xyplex>> define server protocol x25 enabled
X25 Password>> xxxx
After you enable the protocol, and the parameter file has been updated, initialize the
X.25 Gateway for the change to take effect.
0010
27
Basic Use
Enable The Point-to-Point Protocol at PPP Sites
If you want to use the Point-to-Point Protocol (PPP), enable it on the X.25 Gateway at
this time. You must also enable it on the virtual ports where you will send PPP
data, but you cannot enable the protocol on a virtual port if you do not enable it on the
X.25 Gateway. The command that enables PPP is the following:
Xyplex>> define server protocol PPP enabled
PPP Port Characteristics
You can enable PPP port characteristics at this time, including VJ Compression
and IP Broadcasts, and specify such characteristics as the Failure Limit, the
Configure Limit, and the Restart Timer. You can also assign Local and Remote
PPP addresses to ports where you will enable PPP, if your network topology
requires them.
Specify Internet Characteristics for Telnet Implementations
If you are using the Telnet protocol, specify an Internet address for the X.25
Gateway and any nondefault Internet characteristics that you will use. The default
Internet address is 0.0.0.0. The following example shows the commands which
assign an Internet address:
Xyplex>> define server internet address 128.113.0.100
Xyplex>> set server internet address 128.113.0.100
When you assign an Internet address, the X.25 Gateway automatically assigns an
Internet subnet mask, based on the class of the Internet address. For a class B
Internet address, for example, the X.25 Gateway assigns 255.255. 0. 0 as the subnet
mask. To assign a different subnet mask, disable the SUBNET MASK
AUTOCONFIGURE characteristic, and assign a new subnet mask.
The TCP/IP-LAT Software Management Guide describes how to specify other
Internet characteristics that you might need at your site.
28
0010
Basic Use
Enable Accounting Features to Log X.25 Session Information
The X.25 Gateway supports several Communications Server Accounting features
that you can enable at this time. The Accounting feature and the Verbose
Accounting feature record information about X.25 sessions in an Account Log. The
syslogd UNIX daemon records accounting information to a UNIX host as well as
on the X.25 Gateway.
Enabling the Accounting Feature
The X.25 Gateway logs information about X.25 sessions in an account log if you
allocate space for entries in the log. If you want to log this information, use a
command such as the following which allocates space for 500 entries:
Xyplex>> define server accounting entries 500
Enabling the Verbose Accounting Feature
With the Verbose Accounting feature enabled, the X.25 Gateway can log detailed
information about virtual circuits in addition to the session information in the
standard account log. This information includes the address of the caller who
established the virtual circuit, the address of the caller who terminated the virtual
circuit, and the type of service that established it. You must allocate space for the
account log before you can enable the Verbose Accounting feature.
The following command enables the Verbose Accounting feature:
Xyplex>> define server verbose accounting enabled
You must also specify an X.25 address for the X.25 Gateway and enable the X.25
Calling address feature to record addresses in the Verbose Accounting log. The
section on X.25 Gateway Server Management Characteristics, later in this chapter,
describes how to do this.
Enabling the syslogd Daemon
The syslogd UNIX daemon requires that you allocate space for Accounting entries
and enable the Verbose Accounting feature. When you enable the syslogd
daemon, you also specify the Internet address of the UNIX host which will record the
accounting information. Use a command such as the following to enable the
syslogd daemon:
Xyplex>> define server daemon syslogd enabled 140.179.248.81
With the Accounting features enabled, the X.25 Gateway can begin logging
information about X.25 sessions beginning with the first virtual call.
0010
29
Basic Use
Specify X.25 Characteristics
You can modify many X.25 characteristics on the X.25 Gateway, although the
defaults for most may be adequate for your implementation. Some characteristics,
such as X.25 Level 2 and Level 3 parameters, require that you make changes in
accordance with the rules of the PSN. The next sections describe the X.25
characteristics, their default values, and the possible values for each:
X.25 Gateway Server Management Characteristics
Level 2 Parameters and Facilities
Level 3 Parameters and Facilities
See the Chapter 6 for more information about the commands that specify these
characteristics and facilities.
At a minimum, you must define these characteristics to establish a virtual circuit:
The X.25 Address
This is an X.25 Gateway server management
characteristic. You obtain the X.25 address from the PSN
administration, unless you are connected to an X.25 port
on a host.
The range of logical
channel numbers for
virtual circuits
These are Level 3 characteristics. You and the PSN
administration agree on the highest and lowest logical
channel numbers for the permanent and switched virtual
circuits on the X.25 Gateway.
The Opmode
This is a level 3 parameter. The Opmode determines
whether the X.25 Gateway emulates a DTE or a DCE. The
default is a DTE, which is appropriate in most cases.
You define these values in the permanent database of the X.25 Gateway, and you
must initialize the Gateway for them to take effect. The section Initialize the
Gateway, later in this chapter, explains how to do this.
X.25 Gateway Server Management Characteristics
The server management characteristics include the X.25 address, and several
other settings, including those that manage virtual ports and change PAD profiles
and parameters. Except for the X.25 Address, the default values for these
characteristics do not affect basic configuration.
30
0010
Basic Use
Defining the X.25 address
The X.25 address identifies the X.25 Gateway to other devices on the PSN. Usually,
the PSN administration assigns an X.25 address to each device in the network at
subscription time, and you will receive an address for the X.25 Gateway. This
address is a CCITT standard International Data Number (IDN) for PSNs, and
conforms to the X.121 standard for addresses.
If you connect the X.25 Gateway to an X.25 host or another remote X.25 Gateway,
however, you can use an arbitrary address as long as it is different from any other
address already in use. The default address is 1.
Figure 2-3 shows this address in an X.25 Characteristics display.
Xyplex>> show x25 characteristics
Address:
08-00-87-00-2D-44
Buffer Reserve:
Hysteresis:
Small Buffer Size:
Small Buffer Pool:
Large Buffer Size:
Large Buffer Pool:
Address:
1
Welcome:
Name:
X002D44
Number:
0
20
8
81
566
128
1890
Available Profiles:
HOST, CRT, CRT_NOE, CC_SSP, CC_TSP, HARDCOPY, XYPLEX7, XYPLEX8,
XYPLEX9, XYPLEX10, XYPLEX11, XYPLEX12, XYPLEX13, XYPLEX14, XYPLEX15,
XYPLEX16, XYPLEX17, XYPLEX18, XYPLEX19, XYPLEX20, XYPLEX21, XYPLEX22,
XYPLEX23, XYPLEX24, XYPLEX25, XYPLEX26, XYPLEX27, XYPLEX28, XYPLEX29,
XYPLEX30, XYPLEX31, XYPLEX32, XYPLEX33, XYPLEX34, XYPLEX35, XYPLEX36,
XYPLEX37, XYPLEX38, XYPLEX39, XYPLEX40
Enabled Characteristics:
X25
Figure 2-3. An X.25 Characteristics Display
This example changes the X.25 address to 21046004322105:
Xyplex>> define x25 address "21046004322105"
Xyplex>>
Enclose the address in quotes. The address can include from 1 to 15 ASCII digits.
The X25 Characteristics display lists the new address after you initialize the X.25
Gateway.
0010
31
Basic Use
The X.25 address you assign to the X.25 Gateway is the "master" address for the
unit. The subaddress for each virtual port on the unit is a two digit number, based
on the virtual port number. The 80 virtual ports on the X.25 Gateway are numbered
from 02 to 81. For example, the subaddress for virtual port 5 is 05.
Enabling the X.25 Calling Address Feature
When the X.25 Calling Address feature is enabled, call request packets from the
X.25 Gateway include its X.25 address. You may want to enable the X.25 Gateway
Calling Address feature at this time, although it is not always necessary to send
and receive calls across the network. Some hosts may require that call request
packets include the address of the caller so that they can accept or reject the call
based on the calling address. If you are using verbose accounting, this feature
enables the account log to record who initiated or terminated a call.
The following command enables the X.25 Gateway Calling Address feature:
Xyplex>> define x25 calling address enabled
Xyplex>>
Level 2 Parameters and Facilities
Level 2, the link layer, manages the exchange of data between the DTE and the
DCE. This level provides error checking for the data from the physical layer, and
presents error-free data to the next level above, the packet layer. Level 2 also
provides flow control through a series of timers that regulate the speed and density
of the data.
The default values for the Level 2 characteristics on the X.25 Gateway are
compatible with the requirements of many PSNs. These include timer values, the
Extended Frame Sequence Numbering facility, and the window size. Check with
the PSN administration to be sure these values are correct. The X25 Level_2
Characteristics display, shown in Figure 2-4, lists the Level 2 characteristics. This
display shows the characteristics set to the default values.
32
0010
Basic Use
Xyplex>> show x25 level_2 characteristics
Address:
08-00-87-00-2D-44
Protocol:
Opmode:
Window Size:
T1:
T2:
T3:
N2 Counter:
Name:
X002D44
Number:
0
LAPB
DTE
7
3 SECONDS
2 SECONDS
0 SECONDS
20
X.2 Facilities Enabled:
Figure 2-4. Default Settings for Level 2 Characteristics
While the Level 2 Characteristics display shows the Opmode of the X.25 Gateway,
you change this characteristic at Level 3. Table 2-2 lists the Level 2 options.
Table 2-2. Level 2 Options and Default Settings
Level 2 Option
Extended Frame
Sequence
Numbering
N2
DISABLED
20
Function
Determines whether the X.25 Gateway
uses modulo 8 or modulo 128 frame
sequence numbering.
A frame retransmission counter.
T1
3000 milliseconds Specifies how long the X.25 Gateway
can wait for an acknowledgment of a
transmitted frame before it
retransmits the frame.
T2
2000 milliseconds Specifies how long the X.25 Gateway
can wait to acknowledge the receipt of a
message.
T3
0 milliseconds
Window Size
0010
Default Value
7
Specifies how long a channel can be
idle before the X.25 Gateway resets the
link.
Specifies the number of frames that
can remain unacknowledged between
the DTE and the DCE.
33
Basic Use
The command that enables or disables the Level 2 options are:
DEFINE X25 LEVEL_2 option option-value
Where option is one of the Level 2 options in Table 2-1, and option-value is a value
other than the default.
Level 3 Parameters and Facilities
Level 3, the packet layer, establishes virtual circuits and manages the flow of data
across them. Packet formats are defined to initiate and clear calls, to transfer
data, and to execute special functions, including the management of diagnostic
packets. In addition, Layer 3 manages the use of X.2 facilities.
Defining the Range of Virtual Circuits
Recall that a virtual circuit is the logical association between two DTEs on a PSN.
The PSN identifies virtual circuits with logical channel numbers. Among the
Level 3 parameters are those that set the highest and lowest logical channel
numbers for virtual circuits. To send and receive data packets you and the
network administration must agree on the range and mix of virtual circuits.
By default, the X.25 Gateway supports 80 two-way switched virtual circuits, with the
logical channels numbers 1 through 80. You can assign PVCs, and three categories
of CCITT standard SVCs in accordance with the PSN:
SVC
Function
One-Way
Incoming
These circuits can receive calls but not initiate them.
One-Way
Outgoing
These circuits can initiate calls but not receive them.
Two-Way
These circuits can both initiate and receive calls. This is
the default for all VCs on the X.25 Gateway.
One-way SVCs only affect how the call is established; once the two DTEs establish
an SVC, the communication between them is full duplex no matter what rules
governed how the call was initiated or received.
The X.25 Gateway also supports Permanent Switched Virtual Circuits (PSVCs).
PSVCs are a feature of the Xyplex X.25 Gateway, and not a CCITT standard. PSVCs
function like Two-Way SVCs, but do not disconnect the X.25 session when you
terminate the LAN session. You assign PSVCs to specific ports after you assign the
ranges of virtual circuits. See the Xyplex X.25 Gateway Commands Reference
Guide for more information about how to set up PSVCs.
34
0010
Basic Use
In the Xyplex X.25 Gateway implementation, PVCs have direction. The PVC
acquires its direction from the source of the first data it receives: either from the
LAN or from the PSN. As long as the LAN connection remains up, the direction of
the PVC does not affect whether or not you can send or receive data on the PVC.
If the LAN connection is terminated, however, the direction of the PVC determines
whether it will accept data from the LAN or receive data from the PSN. If the
direction of the PVC is LAN-to-X.25, the PVC will discard data it receives from the
PSN bound for the LAN until the LAN session is reestablished. If the direction of
the PVC is X.25-to-LAN, the PVC will accept data it receives from the PSN, but it
will be inaccessible for local LAN connections. The X.25 Gateway maintains the
direction of the PVC until you bring down the link.
Figure 2-5 is a sample Show Server X25 Level_3 Characteristics display with the
default settings for virtual circuits:
Xyplex>> show x25 level_3 characteristics
MAXx25 V1.3
Rom 450000 HW 02.00.00 Lat Protocol V5.2 Uptime:
Address: 08-00-87-00-A6-9E Name: X00A69E
Number:
0
Default Throughput Class:
Default Packet Size:
Default Window Size:
Max Window Size:
Max Packet Size:
Opmode:
Lowest PVC:
Highest PVC:
Lowest Incoming SVC:
Highest Incoming SVC:
Lowest SVC:
Highest SVC:
Lowest Outgoing SVC:
Lowest Outgoing SVC:
X.2 Facilities Enabled:
9600/9600
128
2
7
128
DTE
0
0
0
0
1
80
0
0
T10:
T11:
T12:
T13:
T20:
T21:
T22:
T23:
T28:
R20:
R22:
R23:
R28:
00 00:09:06
0
0
0
0
180
200
180
180
300
255
1
1
1
Figure 2-5. Default Settings for Virtual Circuits
The Highest SVC and Lowest SVC settings in Figure 2-5 refer to two-way switched
virtual circuits.
0010
35
Basic Use
The DCE or DTE cannot set up virtual circuits without the correct range of logical
channel numbers. As you make calls, the DTE assigns logical channel numbers
to virtual circuits from the highest to the lowest values of the specified ranges, and
the DCE assigns values from the lowest to the highest values of the specified ranges.
If, for example, the DCE supports only 30 logical channels, and you do not define
this range on an X.25 Gateway configured as a DTE, the Gateway assigns LCN 80 to
the first outgoing call. The call fails because the DCE cannot interpret the value.
The logical channel numbers for each range of virtual circuit need not be
contiguous. However, the difference between the highest and lowest values in a
range must not exceed 80. If you specify a value in one variable that creates a
difference in excess of this range, the Gateway automatically adjusts the other
variable upward or downward to fit within the range.
The following commands are examples of how to set the LCN ranges for different
types of virtual circuits.
Assigning Permanent Virtual Circuits (PVCs)
The first set of commands assigns the LCN range for PVCs:
Xyplex>> define x25 level_3 lowest pvc 1
Xyplex>> define x25 level_3 highest pvc 10
Because PVCs are a permanent association between two DTEs, you must assign a
logical channel number within the range you specify to each virtual port that
supports a PVC. For example, this command assigns LCN 5 to virtual port 10:
Xyplex>>define x25 port 10 pvc lcn 5
Repeat this command to assign an LCN number to each of the virtual ports that
supports a PVC.
36
0010
Basic Use
Assigning Switched Virtual Circuits (SVCs)
Now assign the SVCs. Remember that you can use two-way SVCs only; you need
not use all three types at your site. SVCs do not require dedicated LCNs, because
SVCs are not permanent and the their LCNs are reused.
Xyplex>> define x25 level_3 lowest incoming svc 256
Xyplex>> define x25 level_3 highest incoming svc 265
Xyplex>> define x25 level_3 lowest svc 1000
Xyplex>> define x25 level_3 highest svc 1049
Xyplex>> define x25 level_3 lowest outgoing svc 2000
Xyplex>> define x25 level_3 highest outgoing svc 2009
The total number of PVCs and SVCs in this example is 80. The X25 Level_3
Characteristics display reflects the new LCNs after you initialize the X.25
Gateway.
Setting the Opmode
The Opmode determines whether the X.25 Gateway emulates a DTE or a DCE. In
most implementations, the gateway emulates a DTE, and this is the default setting
for the OPMODE characteristic. Because the Gateway and the device attached to it
must be complimentary however, you must change the default if the attached device
is a DTE. The command that changes the Opmode is the following:
DEFINE X25 LEVEL_3 OPMODE DTE|DCE
The Level_3 Characteristics Display, shown in Figures 2-5 and 2-7, includes the
Opmode.
Other LEVEL_3 options
Other Level 3 options include the X.2 user facilities, error-recovery timers, and
packet-retry counters. Check with the PSN administration to determine if the
default settings on the X.25 Gateway are appropriate. The default settings for these
facilities and parameters are listed in this section.
User Facilities
The X.2 user facilities allow you to customize the user interface to the network with
features such as Reverse Charging and Fast Select Acceptance. The PSN
administration may or may not support these facilities, and the PSN charges for
them if you subscribe to them. Some facilities apply to all ports for a fixed period of
time, and some apply to individual ports on a per-call basis. In either case, the
0010
37
Basic Use
facilities you enable must agree with those used by the DCE or you may not be able to
establish virtual circuits.
While facilities are a subscription time option, you can enable or disable them on
the X.25 Gateway at any time. All facilities are disabled by default. Table 2-3 lists
the fixed facilities and Table 2-4 lists the per-call facilities that the X.25 Gateway
supports.
38
0010
Basic Use
Table 2-3. User Facilities
Fixed Facilities
Effect when Enabled
Dbit Modification
Indicates that the local DTE expects the remote DTE to
acknowledge that it received a call set-up packet or a data
packet.
Extended Packet
Sequence Numbering
Uses modulo 128 to number packets sent across the X.25 link.
Fast Select Acceptance
Allows the local DTE to accept a call set-up or call clear
packet with up to 128 bytes of user data in it. It also allows the
local DTE to transmit up to 128 bytes of data in a call-accepted
packet.
Flow Control Parameter Permits negotiation on a per-call basis of the packet size and
Negotiation
window size flow control parameters.
0010
Incoming Calls Barred
Allows the DCE to prevent incoming calls to the DTE.
Local Charge
Prevention
Prevents the DCE from accepting calls that require the local
DTE to pay for them.
Default Packet Size
Allows you to change the default packet size.
Default Window Size
Allows you to change the default window size. (You must use
a window size that the PSN supports.)
NUI
Allows the DTE to provide network user identification (NUI)
information to the PSN for billing, security, or network
management.
Outgoing Calls Barred
Prevents the DCE from accepting outgoing calls from the
DTE.
One-way Logical
Channel
Restricts logical channels to either incoming or outgoing
calls.
Packet Retransmission
Allows the X.25 Gateway to issue reject packets.
Reverse Charging
Acceptance
Allows the X.25 Gateway to accept charges for calls from the
PSN with Reverse Charging enabled.
RPOA
Allows the DTE to use a Registered Private Operating
Agency to route calls to a destination in another country.
Throughput Class
Negotiation
Permits the X.25 Gateway to negotiate the throughput classes
for calls in both directions on a per-call basis.
39
Basic Use
Table 2-4. Per-Call Facilities
Per-Call Facilities
Effect when Used
Fast Select
Allows the local DTE to send a call set-up or call clear
packet with up to 128 bytes of user data in it from the ports
you specify.
NUI
Specifies a network user identification (NUI) number to
the PSN, which can use it for billing, security, or
network management.
Packet Size
Determines the maximum packet size that the local X.25
Gateway can attempt to negotiate for calls that originate
at the ports you specify.
RPOA Select
Specifies a transit network owned by a registered private
operating agency (RPOA) that the X.25 Gateway can use
to route international calls from the ports you specify.
Throughput Class
Specifies a throughput class for the calling and called
DTEs at the ports you specify.
Window Size
Specifies the maximum number of packets that can
remain unacknowledged between the calling and called
DTEs at the ports you specify.
Reverse Charging
Allows the X.25 Gateway to request reverse charging for
calls that originate at the ports you specify.
The following is the syntax for the command that enables or disables the user
facilities for all ports on the X.25 Gateway:
DEFINE X25 LEVEL_3 facility ENABLED|DISABLED
Where facility is one of the user facilities in Table 2-3. For the possible values of
the user facilities, see the commands that define each of them in The Xyplex X.25
Gateway Commands Reference Guide.
The following is the syntax for the command that enables or disables the facilities
for individual ports on a per-call basis:
DEFINE/SET [SERVER] X25 PORT facility facility-value
Where facility is one of the facilities in Table 2-4. For the possible values of the percall facilities, see The Xyplex X.25 Gateway Commands Reference Guide.
40
0010
Basic Use
Level 3 Timeouts
The timeout values defined at Level 3 ensure that packet exchanges occur within a
specified period of time. Two categories of timeouts apply to Level 3 procedures:
DCE timeouts and DTE timeouts. The X.25 Gateway default values for these
timeouts are adequate in most implementations. Table 2-5 lists the DCE timeouts
and their default values. Table 2-6 lists the DTE timeouts and their default values.
Table 2-5. DCE Timeouts
Timer
Number
Default in
Seconds
Starts When
Ends When
T10
60
DCE sends a Restart
Indication packet
T11
180
DCE sends an Incoming DCE receives a Call
Call packet
Accepted or a Clear Request
packet
T12
60
DCE sends a Reset
Indication packet
DCE receives a Reset
Confirmation packet
T13
60
DCE sends a Clear
Indication packet
DCE receives a Clear
Confirmation packet
DCE receives a Restart
Confirmation packet
Table 2-6. DTE Timeouts
0010
Timer
Number
Default in
Seconds
Starts when
Ends When
T20
180
DTE sends a Restart
Request packet
T21
200
DTE sends a Call Request DTE receives a Call
packet
Connected or an Incoming
Call packet (collision)
T22
180
DTE sends a Reset
Request packet
DTE receives a Reset
Confirmation packet
T23
180
DTE sends a Clear
Request packet
DTE receives a Clear
Confirmation packet
T28
300
DTE sends a Registration DTE receives a Registration
Request packet
Confirmation packet
DTE receives a Restart
Confirmation packet
41
Basic Use
The command that changes the DTE and DCE timer values has the following
syntax:
DEFINE X25 LEVEL_3 Txx timer-value
Where Txx is one of the timeouts listed in tables 2-5 and 2-6.
Level 3 Retry Counters
The Level 3 retry counters determine the maximum number of times the DTE
sends certain request packets after the specified time limits have expired and the
DTE has not received an appropriate confirmation packet. (The time limits in
Table 2-6 determine how long the DTE will wait before reissuing the packet.) The
X.25 Gateway provides default values for these retry counters, and these defaults
are adequate in most situations. Table 2-7 lists the retry counters and their default
values.
Table 2-7. Level 3 Retry Counters
Retry
Counter
Default
Value
Packet Type
R20
255
R22
1
Reset Request
R23
1
Clear Request
R28
1
Registration Request
Restart Request
The command that changes these retry counter values has the following syntax:
DEFINE X25 LEVEL_3 Rxx retry-counter-value
Where Rx x is one of the retry counters in Table 2-7.
42
0010
Basic Use
Initialize the X.25 Gateway
You must initialize the X.25 Gateway after you define parameters and facilities,
including the X.25 address, the ranges of logical channel numbers, and the
Opmode:
Xyplex>> initialize
While the initialization is taking place, the command interface briefly becomes
inoperative. After you initialize the X.25 Gateway, the software makes the changes
in the permanent database.
To determine whether or not the X.25 Gateway is actively connected to the X.25
network, use the SHOW X25 STATUS command to view a display such as the one
shown in Figure 2-6. The display indicates whether or not each of the three X.25
layers is "Up" or "Down."
Xyplex>> show x25 status
MAXx25 V1.3
Rom 4B0000 HW 00.00.00 Lat Protocol V5.1 Uptime:
Address: 08-00-87-00-A6-9E Name: X00A69E
Large
Large
Large
Large
Small
Small
Small
Small
Buffers Available:
Buffers in Use:
Buffers Total:
Buffer Allocation Failure:
Buffers Available:
Buffers in Use:
Buffers Total:
Buffer Allocation Failures:
State:
Number:
00 00:09:06
0
1624
266
1890
0
565
1
566
0
Line Up/ Frame Up/ Packet Up
Figure 2-6. The Show X.25 Status Display
The State: line shows the status of the three X.25 Layers: Line (level 1), Frame
(level 2), and Packet (level 3). In this display, all three layers are "Up," which
indicates that they are ready to send and receive packets.
0010
43
Basic Use
If a problem existed at any of these layers, the status on the display would be
"Down." For example, if the physical layer is actively connected to the network,
but the data link and packet layers are not functioning properly, the state display
looks like this:
State:
Line Up/ Frame Down/ Packet Down
If this happens at the Frame or Packet layer, check the settings of the characteristics
for that layer on the appropriate displays. If the Line is down, check the hardware
configuration. See Chapter 6, Basic Troubleshooting, for more information about
how to determine specific problems in each layer.
Figure 2-7 shows the settings for the LCN ranges that were defined in the examples
earlier in this chapter.
Xyplex>> show x25 level_3 characteristics
MAXx25 V1.3
Rom 4B0000 HW 00.00.00 Lat Protocol V5.1 Uptime:
Address: 08-00-87-00-A6-9E Name: X00A69E
Default Throughput Class
Default Packet Size:
Default Window Size:
Max Window Size:
Max Packet Size
Opmode:
Lowest PVC:
Highest PVC
Lowest Incoming SVC
Highest Incoming SVC
Lowest SVC:
Highest SVC
Lowest Outgoing SVC
Lowest Outgoing SVC
X.2 Facilities Enabled
9600/9600
128
2
7
128
DTE
1
10
256
265
1000
1049
2000
2009
Number:
T10:
T11:
T12:
T13:
T20:
T21
T22:
T23:
T28:
R20
R22
R23
R28
00 00:09:06
0
0
0
0
0
180
200
180
180
300
255
1
1
1
Figure 2-7. Sample LCN Ranges for Virtual Circuits
This display shows the new logical channel numbers, the default timer values, and
no X.2 facilities enabled.
You can now attempt to establish virtual circuits. Chapter 3, Sending and
Receiving Calls, explains how to do this.
End of Chapter
44
0010
Chapter 3
Sending and Receiving Calls
The process of a local DTE establishing a virtual circuit a with a remote DTE is
known as "making a call." On the X.25 Gateway, you make calls to X.25
addresses and remote users make calls to the X.25 Gateway through virtual ports.
The X.25 Gateway supports 80 virtual ports, numbered 02 through 81, where you can
send and receive calls.
Most of the time, you gain access to virtual ports with local services. The X.25
Gateway supports three types of local services: LAT services, Telnet services, and
X.25 services. LAT and Telnet services provide access to virtual ports for LAN
users. X.25 services provide access to virtual ports for callers from the X.25
network. The X.25 Gateway can support up to 80 local services, and each virtual
port can support up to 80 local services.
This chapter includes these sections which describe how to send and receive calls:
•
Making Calls to the PSN
•
Receiving Calls from the PSN
•
Using Remote Profiles in Local Services
•
Making Calls to a Remote Printer
A local service can change the default inbound or outbound PAD profile on a virtual
port as well as send a remote PAD profile across the PSN to another PAD. This
chapter describes how to include default profiles and remote profiles in local
services. For more information about PAD profiles and parameters, see Chapter 4.
Making Calls to the PSN
To make calls from the LAN to a device on the X.25 network, you can create a LAT
or Telnet service, or assign an X.25 address to one or more virtual ports with a port
connect action. LAT and Telnet services establish sessions between a LAN device,
and an X.25 Gateway virtual port at the PAD interface. Either you or the service
calls the X.25 address. If you use a port connect action, you simply call the virtual
port from a remote device with its node name or port number, and the connect action
automatically calls the X.25 address.
0010
45
Sending and Receiving Calls
Creating a LAT or Telnet Service
A LAT or Telnet service can include several characteristics which determine how
the service makes a connection. Local services are LAT by default. You must
explicitly specify Telnet if you want a Telnet service, and you must explicitly
disable LAT if you want a Telnet only service.
You can assign a LAT or a Telnet service to one or more virtual ports. When a user
requests the service, the Gateway assigns it to a port in the range that is not busy,
and proceeds with whatever activity is specified in the service.
The following is the command syntax which creates a LAT or Telnet service:
DEFINE/SET SERVICE service-name [LAT|TELNET] ENABLED|DISABLED
[PORT port-list | ALL] [CONNECT ACTION "action-string"] [REMOTE CLEAR
ENABLED|DISABLED] [X25 PROFILE "profile-name"] [X25 REMOTE PROFILE
" profile-name" ]
Connecting to the PAD Prompt
To create a simple LAT service that connects to the PAD prompt, specify a service
name and one or more virtual ports in the DEFINE/SET SERVICE command line.
This service has the name PADCONNECT for virtual ports 50-55:
Xyplex>> set service padconnect ports 50-55 enabled
When a user enters the service name, the Gateway makes a connection to the first
port in the range that is not busy:
Xyplex>> connect padconnect
Xyplex-010Session 1 to PADCONNECT on node X00A69 established
*
The default PAD prompt on the X.25 Gateway is an asterisk *. You can change this
with the DEFINE/SET SERVER X25 PROMPT commands. Figure 3-1 represents a
connection from a terminal on the LAN host FinanceVAX to the X.25 Gateway PAD
through the service PADCONNECT.
46
0010
Sending and Receiving Calls
LAN
Virtual
ports
Local Service: PADCONNECT
Ports: 50-55
DEV.SUN.COM
02
..
..
..
.
50
51
52
53
54
55
.
.
.
.
81
Accountshost
PSN
X.25 Address:
345821
FinanceVAX
Figure 3-1. A LAT Service that Returns the PAD Prompt
Calling the X.25 Address from the PAD Prompt
When the PAD prompt appears, you can enter PAD commands, including the CALL
command. To call an X.25 address, you can either enter the CALL command with
the address, or simply enter the address. This example uses the CALL command
and the X.25 address 345821:
* CALL 345821
OUTGOING CALL TO: 345821
*
CALL CONNECTED.
YOU CAN NOW SEND AND RECEIVE DATA
Username>
0010
47
Sending and Receiving Calls
When the remote DTE accepts the call, the PSN establishes a virtual circuit between
the X.25 Gateway and the remote DTE. Both the local and the remote PAD are then
in data transfer state and the two DTEs can send and receive data. At some ports,
you can enter a default recall character, such as @, to recall the PAD to command
state. When you do this, the PAD prompt appears and you can enter PAD
commands.
You can issue many commands other than the CALL command from the PAD
prompt. For an online list of these commands, enter HELP from the PAD prompt.
Chapter 5 of this manual describes PAD commands in detail.
Creating a Local Service that Calls an X.25 Address
To call an X.25 address in a LAT or Telnet service, include the X.25 address of the
remote PAD or host as the connect action in the service. (Enclose the X.25 address
in quotes.) The following command creates a Telnet service with an Internet
address of 128.20.2.30 with a connect action that calls the X.25 address 345821:
Xyplex>> set service accountshost telnet enabled connect action
"345821" internet address 128.20.2.30 ports 60-65
From the Xyplex prompt, a user enters the CONNECT command with the service
name, or the TELNET CONNECT command with the service Internet address.
The X.25 Gateway makes the connection to the host at the X.25 address 345821. The
connection appears to be directly from the terminal server port to the host on the
network. The following example uses the CONNECT command and the service
name:
Xyplex>> connect accountshost
CALL CONNECTED.
YOU CAN NOW SEND AND RECEIVE DATA
Welcome to Accounts Host.
Please Log On
Username:
You can also enter telnet connect 128.20.2.30 to make the connection.
Figure 3-2 shows a call from a user on the LAN host DEV.SUN.COM to the X.25
address 345821 with the local service ACCOUNTSHOST.
48
0010
Sending and Receiving Calls
LAN
Virtual
ports
DEV.SUN.COM
02
..
..
..
.
.
60
61
62
63
64
65
.
.
.
81
Local Service: ACCOUNTSHOST
Ports: 60-65
Connect Action: "345821"
Accountshost
PSN
X.25 Address:
345821
FinanceVAX
Figure 3-2. A Telnet Service that Calls an X.25 Address
Figure 3-2 shows that the local service has associated the call with virtual port 60. If
this port had been busy, the service would have attempted to make a connection with
the next port in the range. In this case, the next port is 61.
Assigning an X.25 Address to a Virtual Port
When you assign an X.25 address to a virtual port with a port connect action, the
X.25 Gateway calls that address whenever anyone logs on to the port through the
LAT or Telnet protocol. If you made the call from a Xyplex terminal server, for
example, you could use the TELNET CONNECT or LAT CONNECT commands.
This method of calling an X.25 address from the LAN eliminates the need for a
local service.
The following commands assign an X.25 address to a virtual port:
DEFINE/SET [SERVER] X25 PORT port-list CONNECT ACTION
" address* Duserdata"
0010
49
Sending and Receiving Calls
The address is an X.25 address. *Duserdata field is optional, and can include up to
12 characters. The following command assigns the address 7654 to ports 10-20:
Xyplex>> set x25 port 10-20 connect action "7654"
Users can now use LAT or Telnet to call virtual ports 10-20 to connect the X.25
address 7654. The following command uses LAT to connect to port 10 on the X.25
Gateway from an X.25 Terminal Server:
Xyplex>> lat connect node 6625 port 10
CALL CONNECTED.
YOU CAN NOW SEND AND RECEIVE DATA
Welcome to Remote X.25 Host.
Please Log On
Username:
You can call X.25 Gateway virtual ports from other hosts on the network. See the
host-specific documentation about the commands you can use to do this.
Changing the Outbound PAD Profile
Some LAT and Telnet services, such as those that make calls to remote printers,
may require a change in the outbound profile for the range of virtual ports in the
service. The service need not have a connect action associated with it. The
following example defines a LAT service with an outbound profile:
Xyplex>> set service padconnect port 12-14 x25 profile "hardcopy"
While the service padconnect is active, the outbound profile for ports 12-14 is
Hardcopy. At other times, the outbound profile for these ports is either the X.25
Gateway default, or the profile for another service that is in use at these ports.
Viewing LAT and Telnet Services
The Show Service Local Summary display lists the LAT, Telnet, and X.25 services
on the X.25 Gateway. Figure 3-3 shows a sample display:
Service Name
Status
Identification
padconnect
Available
Connection to PAD
accountshost
Available
X.25 to accountshost
Figure 3-3. A Sample Show Service Local Summary Display
This display includes the service name, the status of the service, and a text string
which identifies the service. The Show Service service-name Characteristics
display lists the details of the service you specify. See The Xyplex X.25 Gateway
Commands Reference Guide for more information about these displays.
50
0010
Sending and Receiving Calls
Calling the LAN from the PSN
The X.25 Gateway can follow one of several procedures when it receives a call from
the PSN. Which one it follows depends on two characteristics that apply to virtual
ports: the listen address and the X.25 port connect action.
You can create X.25 services which include a listen address as well as other service
characteristics. The syntax for X.25 services is the following:
DEFINE/SET SERVICE service-name X25 ENABLED|DISABLED [PORT port-list|ALL]
[CONNECT ACTION "action-string"] [X25 ADDRESS "listen-address"] [REMOTE
CLEAR ENABLED|DISABLED] [X25 PROFILE "profile-name"] [X25 REMOTE PROFILE
" profile-name" ]
About the Listen Address
When a user calls an X.25 Gateway virtual port, the calling address includes the
X.25 address (IDN) of the X.25 Gateway and a listen address for one or more virtual
ports. The default listen address for each virtual port is its two-digit port number:
the default listen address for port 38, for example, is 38. The default listen address
for port 5 is 05. The listen address for a virtual port appears in the X.25 Port
Alternate Characteristics display, as shown in Figure 3-4 for port 38.
Virtual Port:
38
10 Feb 1994
21:41:16
Listen Address: 38
Send Carriage Return:
Disconnect:
Remote Clear:
Disabled
Enabled
Disabled
Figure 3-4. A Default Listen Address
Changing the Default Listen Address
You can change the listen address of a virtual port with an X.25 service. The listen
address in the service can include part or all of the X.25 Gateway IDN number, plus
the two-digit extension that identifies the port. Like an X.25 address, a listen
address can include up to 15 digits. You and the PSN administration agree at
subscription time on the addressing scheme to use for the X.25 Gateway. If the X.25
Gateway is connected to another X.25 Gateway or an X.25 host, the listen addresses
can be any number up to 15 digits
The first time you define a listen address that is different from the default, the
default listen address no longer exists. Only the listen addresses you specify in
0010
51
Sending and Receiving Calls
X.25 services are valid for that port. If you clear or purge all services associated
with a port, the listen address reverts to the default.
When a call arrives at the X.25 Gateway, the Gateway compares the calling address
with the listen address of each virtual port, starting with port 02. The comparison
begins with the least significant digits of the calling address. The X.25 Gateway
establishes the connection with the a virtual port at a matching listen address that is
not busy. Figure 3-5 shows several nondefault listen addresses corresponding to
virtual ports on an X.25 Gateway:
Virtual
ports
Listen
addresses
02
.
.
.
.
.
02
35
99
36
1099
37
799
38
699
39
6799
40
.
.
.
.
.
.
99
81
81
PSN
call 12345 6799
X.25 Gateway address: 1234567
Figure 3-5. Listen Addresses on an X.25 Gateway
When the calling address 123456799 arrives at the X.25 Gateway, the X.25 Gateway
matches the listen address 99 with virtual port 35. Other virtual ports with
matching listen addresses are 37, 39, and 40.
52
0010
Sending and Receiving Calls
You can associate a listen address with one virtual port or a range of virtual ports.
The listen address for the range may be the subaddress of one of the ports in the
range, or the IDN number for the Gateway that the PSN administration assigns to
it. When a user calls the listen address, the X.25 Gateway associates the call with a
port in the range that is not busy. A range can include all 80 virtual ports on the
X.25 Gateway.
Each virtual port can support up to 80 listen addresses, because 80 is the maximum
number of local services the X.25 Gateway can support. Figure 3-6 represents a
range of virtual ports with different listen addresses assigned to them.
02
.
.
.
.
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
.
.
.
.
.
Virtual
ports
nondefault
listen addresse s
3338 (ports 38-41)
9999 (port 42)
3345 (ports 37-49)
3343 (ports 43-50)
81
Figure 3-6. Multiple Listen Addresses
In Figure 3-6, port number 38 has the listen addresses 3338 and 3345. Port number
48 has the listen addresses 3345 and 3343. Ports 35 and 36 have default listen
addresses. Port 42 has the listen address 9999.
0010
53
Sending and Receiving Calls
Figure 3-7 is an X.25 Port Alternate Characteristics display for port 38, showing the
nondefault listen addresses represented in Figure 3-6.
Virtual Port:
38
Listen Address:
10 Feb 1994
21:41:16
3338, 3345
Send Carriage Return:
Disconnect:
Remote Clear:
Disabled
Enabled
Disabled
Figure 3-7. Two Nondefault Listen Addresses
The syntax for the command that specifies a nondefault listen address for one or
more virtual ports is the following:
DEFINE/SET SERVICE servicename X25 ENABLED X25 ADDRESS "listen
address" PORT port-list
About the X.25 Port Connect Action Type
When a call arrives at a virtual port, the X.25 Gateway directs it to either the Xyplex
command interface or a LAN destination, based on the connect action type of the
virtual port. (Connect action types are separate from the local connect actions in the
X.25 services.) Three X.25 connect action types are available: None, Autoconnect,
and Userdata.
54
None
This connect action type returns the Xyplex command interface to
callers from the PSN. This is the default connect action type for
all virtual ports.
Autoconnect
This connect action type depends on the association of one or more
virtual ports with an X.25 service. The service contains a Xyplex
command that you specify, such as CONNECT, which can
establish a session with a LAN destination.
Userdata
This connect action type interprets the information in the
* Duserdata field of a PAD CALL command as the address of a
LAN destination. The X.25 Gateway automatically issues a
CONNECT command to establish a session at this LAN address.
0010
Sending and Receiving Calls
The connect action type for each virtual port on the X.25 Gateway appears in the
Show/List Server X25 Port Characteristics display. Figure 3-8 is a sample display
for virtual port 10, set to the default connect action type.
Virtual Port:
Conn Action Type
Permanent SVC:
PVC LCN:
10
:
Packet Size:
Window Size:
Throughput Class:
Reverse Charging:
Fast Select:
NUI:
RPOA Select:
14 Jan 1994
18:29:16
NONE
DISABLED
N/A
128 128
2 2
9600 9600
DISABLED
DISABLED
Connect Action
Default Inbound Profile: HOST
Default Outbound Profile: CRT_NOE
Call Facilities enabled:
Figure 3-8. A Default Connect Action Type
The syntax for the command that specifies an X.25 port connect action type is this:
DEFINE/SET [SERVER] X25 PORT port-list CONNECT ACTION TYPE
NONE
AUTOCONNECT
USERDATA
Connect Action Type: None
When the connect action type at a virtual port is None, a caller from the PSN
establishes a session with the Xyplex command interface. After the caller logs on to
the interface, he or she can enter any Xyplex command from the Xyplex> prompt as
long as the privilege level on the port is appropriate. For example, the caller can
enter a CONNECT command or a DEFINE command such as DEFINE PORT PPP
ENABLED. The caller must be familiar with the Xyplex command interface,
which may not be true for all callers.
The default connect action type for all virtual ports is None. If you call an X.25
Gateway virtual port from the PSN using a default listen address, and the connect
action type for that port is None, you can establish a session with the X.25 Gateway
without using an X.25 service.
0010
55
Sending and Receiving Calls
The services you create for virtual ports with connect action type None can define a
listen address, a profile, and a remote profile, or enable the Remote Clear
characteristic. These services cannot include a connect command to a LAN
destination; a port must have an Autoconnect connect action type to support a
service that does this. If a service includes a connect action for a virtual port with
connect action type None, then X.25 Gateway ignores the connect action in the
service.
This example assumes that the address on the X.25 Gateway is 99762. A remote user
calls the virtual port with the listen address 22, which has the connect action type
None. The call from the remote PAD looks like this:
* call 9976222
CALL CONNECTED.
YOU CAN NOW SEND AND RECEIVE DATA
Welcome to the X.25 Gateway
The caller can then log in to the Xyplex command interface, and enter Xyplex
commands. To establish a session with the LAT host FinanceVAX, for example,
the caller enters the CONNECT command after logging in to the X.25 Gateway
virtual port:
Enter username> lynne
Xyplex>
Xyplex> connect financevax
Welcome to FinanceVAX.
Please log on.
Username:
56
0010
Sending and Receiving Calls
Figure 3-9 represents the activity between the remote PAD and the X.25 Gateway
when the caller issues a CALL command to a listen address for a port with the
connect action type None.
LAN
Virtual
ports
DEV.SUN.COM
FinanceVAX
02
.
.
.
20
21
22
23
24
25
.
.
.
.
.
81
Listen address: 22
22
PSN
call 9976222
Xyplex>
X.25 Gateway
Address: 99762
Figure 3-9. Connect Action Type None
The example in Figure 3-9 shows a call to the default listen address for port 22 on an
X.25 Gateway. In this example, no X.25 service exists for port 22.
0010
57
Sending and Receiving Calls
Connect Action Type: Autoconnect
The Autoconnect connect action type associates one or more virtual ports with an
X.25 service when a call arrives at one of the virtual ports. The connect action in
the service issues a Xyplex command that you specify, such as CONNECT, which
establishes a session with a LAT, Telnet, or TN3270 device on the LAN. Typical
commands that you use in services for Autoconnect ports include these:
CONNECT, LAT CONNECT, TELNET CONNECT, and RLOGIN.
This example assigns the Autoconnect connect action type to ports 11-15:
Xyplex>> define x25 port 11-15 connect action type autoconnect
This X.25 service, associated with ports 11-15, includes a LAT service name as the
variable in the CONNECT command, and a listen address for ports 11-15:
Xyplex>> define service dev.sun.com x25 enabled connect action
"connect dev.sun.com" x25 address "6215" ports 11-15
When a caller on the PSN calls the listen address 6215, the X.25 Gateway associates
the call with a virtual port in the range 11-15 that is not busy. The X.25 Gateway
then issues the command connect dev.sun.com from the port. From the caller's
screen, the call and response look like this:
* call 9976215
CALL CONNECTED.
YOU CAN NOW SEND AND RECEIVE DATA
Welcome to DEV.SUN.COM
Please enter your username and password.
Username:
58
0010
Sending and Receiving Calls
Figure 3-10 represents the activity between the remote PAD and the X.25 Gateway
when the user on the remote PAD executes the CALL command to listen address
6215.
LAN
X.25 Service: DEV.SUN.COM
Virtual
ports
DEV.SUN.COM
02
.
.
.
11
12
13
14
15
.
.
.
.
.
81
FinanceVAX
Listen address: 6215
Ports: 11-15
Connect Action: CONNECT DEV.SUN.COM
PSN
6215
call 9976215
Welcome to
DEV.SUN.COM
Username:
X.25 Gateway
Address: 99762
Figure 3-10. Connect Action Type Autoconnect
In Figure 3-10, the call arrives at listen address 6215, which includes virtual ports
11-15 through the service DEV.SUN.COM. In this example, the service connects the
call to virtual port 11, but if that port were busy, the service would attempt to connect
the call to another port in the range. When the service finds a free virtual port, it
issues the CONNECT command to DEV.SUN.COM.
0010
59
Sending and Receiving Calls
Connect Action Type: Userdata
The Userdata connect action type require that you specify a LAN destination in the
* Duserdata field of the incoming call request packet. When a call arrives at a
Userdata port, the X.25 Gateway automatically issues the CONNECT command
using the LAN destination, and establishes a session with that destination. This
type of connect action gives the caller the flexibility to choose among different LAN
destinations from the remote PAD interface, rather than from the Xyplex command
interface. You can create Userdata connections with or without a service that
specifies a listen address, an inbound profile, and a remote profile for a range of
virtual ports.
The *Duserdata field is limited to 12 characters. Therefore, any LAN address you
specify in this field must not exceed 12 characters. Do not include the CONNECT
command in this field.
This example assigns the Userdata connect action type to ports 40-45.
Xyplex>> set x25 ports 40-45 connect action type userdata
The following X.25 service associates ports 40-45 with a listen address. The service
does not include a connect action because this is already implied by the Userdata
characteristic.
Xyplex>> define service userlisten x25 enabled ports 40-45 x25 address
"4045"
The call from the remote PAD to a listen address associated with a Userdata port
looks like this:
* call 9976244045d*Ddev.sun.com
CALL CONNECTED.
YOU CAN NOW SEND AND RECEIVE DATA
Welcome to DEV.SUN.COM
Please enter your username and password.
Username:
60
0010
Sending and Receiving Calls
Figure 3-11 represents the activity between the remote PAD and the X.25 Gateway
when the user on the remote PAD executes the CALL command to listen address
4045:
LAN
X.25 Service: USERLISTEN
Listen address: 4045
Ports: 40-45
Virtual
ports
DEV.SUN.COM
FinanceVAX
02
..
..
..
.
40
41
42
43
44
45
.
.
.
.
81
PSN
4045
call 997624045d*Ddev.sun.com
Welcome to
DEV.SUN.COM
Username:
X.25 Gateway
Address: 99762
Figure 3-11. Connect Action Type Userdata
In Figure 3-11, a call with the host name DEV.SUN.COM in the *Duserdata field of
the call request packet arrives at listen address 4045. The X.25 Gateway
determines that the first free port in the range at this listen address is 41, which has
the Userdata connect action. The X.25 Gateway software issues the command
CONNECT DEV.SUN.COM from virtual port 41.
0010
61
Sending and Receiving Calls
Changing the Inbound PAD Profile in an X.25 Service
Certain X.25 services, such as those that direct calls to a printer on the LAN, may
require a change in the inbound profile for the range of virtual ports in the service.
The service need not have a connect action associated with it. The following
example defines an X.25 service with an inbound profile for ports with an
Autoconnect connect action to a laser printer:
Xyplex>> set service printerconnect x25 enabled connect action "connect
laser2" x25 profile "hardcopy" x25 address "3579" ports 16-18
While the service printerconnect is active, the inbound profile for ports 16-18 is
Hardcopy. At other times, the outbound profile for these ports is either the X.25
Gateway default, or the outbound profile for another service that is in use at these
ports.
Viewing X.25 Services
The Show Service Local X25 Summary display lists all local X.25 services on the
X.25 Gateway. Figure 3-12 shows a sample display:
MAXx25 V1.3
Rom 4C0000 HW 00.01.00 Lat Protocol V5.1 Uptime:
Service Name
dev.sun.com
userlisten
printerconnect
00 00:09:06
Listen Address
Profile
Remote Profile
1156
4045
3579
none
none
hardcopy
none
none
none
Figure 3-12. A Show Service Local X.25 Summary Display
The display includes the name of each service, the listen address in the service, the
X.25 profile, and the X.25 remote profile.
Using Remote PAD Profiles in Local Services
Some implementations may require that you change the parameter settings on a
remote PAD when you send data to it or receive data from it. To do this, you send a
remote profile to the PAD, which overwrites the default inbound or the default
outbound profile on that PAD. For example, you might want to send a file to a
printer on a remote PAD which has an inbound profile set to receive data for video
terminals. You can change the profile on the remote PAD to one that supports
printers for the duration of the call with a remote profile in a local service. (For
more information about specific PAD parameters and profiles, see Chapter 4.)
62
0010
Sending and Receiving Calls
You can also associate remote profiles directly with virtual ports, rather than
through a service. If you do, however, any call that uses that port sends the remote
profile. If you specify the remote profile in a service, only those calls that use the
service send the remote profile. In addition, a remote profile in a service overrides
a remote profile directly associated with a port.
The CLEAR X25 PROFILE command clears parameter settings within a profile, so
that you can send only specific parameters to the remote PAD. See The Xyplex X.25
Gateway Commands Reference Guide for more information about the CLEAR X25
PROFILE command.
Remote Profiles in LAT and Telnet Services
A remote profile in a LAT or Telnet service overwrites the default inbound profile
of the remote PAD when the call arrives at the PAD. For example, this command
specifies the profile Hardcopy as the remote profile for ports 20-25 in a Telnet
service:
Xyplex>> set service accountshost telnet enabled connect action "345820"
internet address 128.10.2.30 ports 20-25 x25 remote profile "hardcopy"
This service, which calls the X.25 address 345820 through virtual ports 20-25,
overwrites the inbound PAD profile at 345820 and replaces it with the profile
Hardcopy.
Remote Profiles in X.25 Services
A remote profile in an X.25 service overwrites the default outbound profile of the
remote PAD when a call arrives at the listen address in the X.25 service. When the
call arrives at the listen address, the local service sends a packet containing the
profile to the remote PAD. This command specifies the profile Hardcopy for ports
75-78 in an X.25 service.
Xyplex>>set service remoteprint x25 enabled connect action
"connect LANprinter" x25 address "657275" x25 remote profile
"hardcopy" ports 75-78
When a call arrives at the listen address 657275, the X.25 Gateway sends the profile
Hardcopy to the calling PAD. This profile overwrites the outbound profile on this
PAD.
0010
63
Sending and Receiving Calls
Using Remote Profiles in a Large Network
If you are designing a large network with several X.25 Gateways, and many local
services, use remote profiles with care. If a local service with a remote profile calls
a listen address on an X.25 Gateway which is associated with an X.25 service that
also has a remote profile, the inbound and outbound profiles on both PADs will be
overwritten. This can have a negative effect on the data being transferred. If you
assign a remote profile to a port or include one in a local service, be sure to inform
the other sites on the PSN that you have done so.
Making Calls to a Remote Printer
To successfully print files across the PSN on a remote printer, you must set specific
values for characteristics on the local service making the call and the virtual ports
in the local service. If the remote printer is attached to another X.25 Gateway, you
must also create a local service for the virtual port associated with the printer on the
remote X.25 Gateway. A remote printer attached to a generic PAD does not need
specific settings.
Setting Characteristics for Virtual Ports
Define the ports associated with the local service as PVCs or PSVCs. This ensures
that data bound for the remote printer does not get lost if the local LAN connection is
terminated. The X.25 Gateway Commands Reference Guide, and Chapter 2 of this
manual, explain how to define a virtual port as a PSVC or a PVC.
Creating the Local Service on the Local X.25 Gateway
LAT or Telnet services that make calls to a remote printer on the PSN must have
certain characteristics enabled, and include an X.25 profile set with certain
parameter values. If the call is to a printer attached to a generic PAD, the service
must include an X.25 profile to overwrite the default outbound profile on the local
PAD. If the call is to a printer another X.25 Gateway, the service must include an
X.25 profile and an X.25 remote profile to overwrite the default inbound profile on
the remote PAD.
The LAT or Telnet service must have characteristics must be enabled:
CONNECTIONS, QUEUE. These characteristics are enabled by default, so you do
not have to change them unless they have been disabled. See the TCP/IP LAT
Commands Reference Guide for more information about these service
characteristics.
64
0010
Sending and Receiving Calls
Set these PAD parameters to the following values in the X.25 profile and the X.25
remote profile:
Parameter
Value
1 (PAD Recall)
2 (Echo)
3 Data Forwarding
4 Idle Timer
6 PAD Service Signals
0 (PAD recall is not possible)
0 (Disabled)
0 (No Data Forwarding Character)
2 (40 milliseconds)
1 (send all service signals in the standard format)
You can use the CLEAR SERVER X25 PROFILE command to clear all parameters
except those that you want to send to the remote PAD.
Creating the Local Service on the Remote X.25 Gateway
The port associated with the printer on the remote X.25 Gateway must have an X.25
service designed to receive the call from the local X.25 Gateway. It must include an
Autoconnect connect action to the printer on the LAN. Both the local port that sends
the call and the remote port that receives the call must be defined as a PVC or a
PSVC.
Example of a Call to a Remote Printer
This example creates a local service to call a remote printer attached to another
X.25 Gateway. The first step assigns PSVC support to port 2, the port in the service.
Xyplex>> define x25 port 2 permanent svc enabled
Xyplex>>
Initialize the X.25 Gateway for the DEFINE command to take effect.
The next step creates a Telnet service to call a remote printer at the listen address
9924. The X.25 profile in the service has the parameters set to the correct values, as
does the X25 remote profile. The Internet address is the address associated with the
service. The Xyplex print filter uses this address as its destination.
Xyplex>> define service printsrv port 2 telnet enabled internet address
140.179.80.181 connect action "9924" x25 profile "print prof" x25 remote
profile "remoteprnt"
On the remote X.25 Gateway, the virtual port where the call will arrive has
Autoconnect as the port connect action type. It is also defined as a PSVC. In this
example, the virtual port is 3:
Xyplex>> define x25 port 3 connect action type autoconnect
0010
65
Sending and Receiving Calls
The final step creates an X.25 service on the remote X.25 Gateway which listens for
the incoming call form the local X.25 Gateway through the listen address 9924.
This service includes a connect action which automatically establishes a session
with the printer. In this example, the connect action includes the name of the
printer, but it could include the Internet address of the printer instead.
Xyplex>> define service printconnect x25 enabled port 3 x25
address "9924" connect action "connect printer"
Xyplex>>
The local X.25 Gateway can now send data to the remote printer when a user
connects to the service printsrv.
End of Chapter
66
0010
Chapter 4
X.3 PAD Profiles and Parameters
CCITT recommendation X.3 defines twenty-two PAD parameters which specify
how the PAD sends data to and receives data from an asynchronous terminal
device. Groups of parameters are combined into profiles that match the
characteristics of the device connected to the PAD. The X.25 Gateway
automatically uses one of these profiles when you establish a virtual circuit, based
on the type of asynchronous device you are using and whether your X.25 connection
is incoming or outgoing.
Each virtual port has a default inbound and outbound profile, but you can change
these profiles to suit your configuration. The X.25 Gateway supports forty profiles
that you can modify. You can also send a profile from the X.25 Gateway to a remote
PAD. The remote profile overwrites the existing profile on the remote PAD.
This chapter describes the X.25 Gateway PAD profiles and how to change them. It
includes a description of each PAD parameter and the values that apply to them.
The following sections explain these topics:
•
The X.25 Gateway profiles
•
PAD Parameter Summary
•
Changing Local Profiles and Parameters
•
Changing Remote Profiles and Parameters
•
PAD Parameter Descriptions
Although the X.25 Gateway PAD references virtual ports rather than physical ports,
the PAD applies the parameter values to the virtual port whenever possible. Some
parameters, however, such as binary speed, have no meaning to a virtual terminal
port. The descriptions of each parameter at the end of this chapter indicate whether
or not the parameter applies to virtual ports.
0010
67
PAD Parameters
The X.25 Gateway PAD Profiles
Each of the X.25 Gateway profiles has a number and a name, or profile identifier,
associated with it. You use the profile identifier to specify the profile in PAD
commands and Xyplex commands. Table 4-1 lists each predefined profile on the
X.25 Gateway and describes its purpose.
Table 4-1. X.25 Gateway Profiles
Profile Identifier
Default?
Purpose
HOST
Yes
This is the default profile for incoming calls to
video terminals.
CC_SSP
No
This is the CCITT standard "normal" profile,
designed for the transfer of ASCII files.
CC_TSP
No
This is the CCITT standard "transparent"
profile, designed to transfer binary data.
CRT
Yes
This is the default profile for outgoing calls from
video terminals. This profile has Parameter 2
Echo enabled, so that characters appear on the
screen when you enter them from the keyboard.
HARDCOPY
No
This profile has parameters set for printing
terminals. You can use it for incoming or
outgoing calls.
CRT_NOE
No
This is an optional profile for either inbound or
outbound calls, with Parameter 2 Echo disabled.
Characters that you enter from the keyboard do
not appear on the screen.
Xyplex7 through
Xyplex40
No
These profiles have parameter values set to those
of the HOST profile. You can rename and
modify them for particular applications.
68
0010
PAD Parameters
The Show/List Server X25 Characteristics display includes the profiles available
on the X.25 Gateway. Figure 4-1 shows this display with the default profile names.
Buffer Reserve:
Hysteresis:
Small Buffer Size:
Small Buffer Pool:
Large Buffer Size:
Large Buffer Pool:
Address:
PAD Prompt:
Welcome:
20
8
81
566
128
1890
1
Available Profiles:
HOST, CRT, CRT_NOE, CC_SSP, CC_TSP, HARDCOPY, XYPLEX7, XYPLEX8
XYPLEX9, XYPLEX10, XYPLEX11, XYPLEX12, XYPLEX13, XYPLEX14, XYPLEX15, XYPLEX16
XYPLEX17, XYPLEX18, XYPLEX19, XYPLEX20, XYPLEX21, XYPLEX22, XYPLEX23, XYPLEX24
XYPLEX25, XYPLEX26, XYPLEX27, XYPLEX28, XYPLEX29, XYPLEX30, XYPLEX31, XYPLEX32
XYPLEX33, XYPLEX34, XYPLEX35, XYPLEX36, XYPLEX37, XYPLEX38, XYPLEX39, XYPLEX40
Enabled Characteristics:
X25
Figure 4-1 An X.25 Server Characteristics Display
The Show/List Server Port Characteristics display shows the default inbound and
outbound profiles for the port you specify. Figure 4-2 shows the Xyplex defaults for
these profiles.
Listen Address:
12
Xyplex> show server x25 port 12 characteristics
Virtual Port:
12
Connect Action:
NONE
Permanent SVC:
DISABLED
PVC LCN:
N/A
Packet Size:
Window Size:
Throughput Class:
Reverse Charging:
Fast Select:
NUI:
RPOA Select:
17 Jan 1994
18:44:48
128 128
2 2
9600 9600
DISABLED
DISABLED
Default Inbound Profile: HOST
Default Outbound Profile: CRT
Call Facilities enabled:
Figure 4-2. An X.25 Port Characteristics Display
0010
69
PAD Parameters
PAD Parameter Summary
Each of the twenty-two parameters in a PAD profile has a number associated with it,
assigned by the CCITT standard:
1 PAD Recall
2 Echo
3 Data Forwarding
4 Idle Timer
5 Ancillary Device Code
6 Control of PAD Service Signals
7 PAD Operation of Receipt of Break
8 PAD Discard
9 Padding after <CR>
10 Line Folding'
11 Binary Speed
12 Flow Control
13 Linefeed Insertion After CR
14 Linefeed Padding
15 PAD Editing
16 Character Delete
17 Line Delete
18 Line Display
19 Editing PAD Service Signals
20 Echo Mask
21 Parity Treatment
22 Page Wait
Table 4-2 lists the default parameter values, if they are set, for the X.25 Gateway
profiles. Some parameters do not have a value set by default. If this is the case, the
table shows n/v (no value), in place of a parameter value.
The parameters in the profiles XYPLEX7 through XYPLEX40 are set to the same
values as the HOST profile. Later sections of this chapter explain how each
parameter value affects the operation of the PAD. A table similar to Table 4-2, but
without profile names or parameter values, appears in Appendix C. You can use
this table to record new profile names and parameter values when you modify the
existing ones.
70
0010
PAD Parameters
Table 4-2. Default parameter values for the X.25 Gateway PAD profiles.
Parameters
Profiles
HOST
CC_SSP
CC_TSP
CRT
HARD
COPY
CRT_NOE
1 PAD Recall
n/v
1
n/v
64
64
64
XYPLEX
7-40
n/v
2 Echo
n/v
n/v
n/v
1
1
n/v
n/v
3 Data
Forwarding
4 Idle Timer
n/v
2
n/v
127
2
127
n/v
1
n/v
2
2
n/v
2
1
5 Ancillary
Device Code
6 Control of PAD
Service Signals
7 PAD Operation
of Receipt of Break
8 PAD Discard
n/v
n/v
n/v
n/v
2
n/v
n/v
5
5
n/v
5
5
5
n/v
n/v
21
21
2
21
2
n/v
n/v
n/v
n/v
n/v
n/v
n/v
n/v
9 Padding After
<CR>
1 0 Line Folding
n/v
n/v
n/v
n/v
5
n/v
n/v
n/v
n/v
n/v
n/v
80
n/v
n/v
1 1 Binary Speed
14
14
14
14
n/v
14
14
1 2 PAD Flow
Control
1 3 Linefeed
Insert After <CR>
1 4 Linefeed
Padding
1 5 PAD Editing
n/v
n/v
n/v
1
1
1
n/v
n/v
n/v
n/v
4
4
4
n/v
n/v
n/v
n/v
n/v
5
n/v
n/v
n/v
n/v
n/v
n/v
1
n/v
n/v
16 Character
Delete
1 7 Line Delete
n/v
127
n/v
127
8
127
n/v
n/v
24
n/v
24
24
24
n/v
1 8 Line Display
n/v
18
n/v
18
18
18
n/v
1 9 Editing PAD
Service Signals
20 Echo Mask
n/v
3
3
2
1
2
n/v
n/v
n/v
n/v
n/v
n/v
n/v
n/v
2 1 Parity
Treatment
22 Page Wait
n/v
n/v
n/v
3
3
3
n/v
n/v
n/v
n/v
n/v
n/v
n/v
n/v
0010
71
PAD Parameters
The Show Server X25 Profile display shows the value of each parameter in the
profile you specify. Figure 4-3 is the display for the profile HARDCOPY.
Profile
6: HARDCOPY
PAD Recall(1):
Data Forwarding Character(s)(3):
Ancillary Device Control(5):
Break Signal Operation(7):
Padding after CR(9):
Binary Speed(11):
Linefeed Insertion after CR(13):
Editing(15):
Line Delete(17):
Editing PAD Service Signals(19):
Parity Treatment(21):
64
2
2
21
5
4
1
24
1
3
Echo(2):
Idle Timer Delay(4):
PAD Service Signals Control(6):
Discard Output(8):
Line Folding(10):
Flow Control of the PAD(12):
Linefeed Padding(14):
Character Delete(16):
Line Display(18):
Echo Mask(20):
Page Wait(22):
5
80
1
5
8
18
Figure 4-3. An X.25 Profile Display for the Profile HARDCOPY
The Show/List Server X25 Port Alternate Characteristics display includes the
parameter values of the profile currently in use if a virtual circuit is active at the
port you specify. Figure 4-4 is sample display for port 12.
Virtual Port:
Listen Address:
12
12
Send Carriage Return:
Disconnect:
Remote Clear:
17 Jan 1994
16:26:56
Disabled
Enabled
Disabled
Current X.3 Parameters:
1: 64 2: 1
12: 1 13: 4
3: 2 4: 0 5: 0 6: 5 7: 21 8: 0 9: 5 10: 80 11: 14
14: 5 15: 1 16: 8 17: 24 18: 18 19: 1 20: 0 21: 3
22:0
Figure 4-4. A Sample Alternate Characteristics Display for Port 12
Changing Local Profiles and Parameters
The X.25 Gateway provides three methods for changing the inbound and outbound
profiles associated with a virtual port: through PAD commands, through Xyplex
commands, and through local services. This section describes each of these
methods.
72
0010
PAD Parameters
Using PAD Commands
PAD commands can change local profiles, reset parameters within local profiles,
and display local profiles and parameters. When you change a profile with a PAD
command, the change takes precedence over any profile or parameter setting
specified in a Xyplex command or a local service. The change remains in effect
until you terminate the virtual circuit. After you terminate the virtual circuit, the
profile reverts to the default with all the original parameter settings.
The PAD commands that effect profiles and parameters on the local X.25 Gateway
PAD are these:
PROF?
Display the profiles on the local PAD.
PROF
Change the outbound profile on the local PAD.
PAR?
Display one or all the parameters of the currently used profile on the
local PAD. (The terminal must be in 132 column mode for all
values to appear.)
SET?
Change a parameter in the local PAD profile and display the new
value.
SET
Change a parameter in the local PAD profile and do not display the
new value.
See Chapter 5 for detailed information about each of these commands.
Using Xyplex Commands
Xyplex commands can change the default inbound and outbound profiles at one or
more virtual ports, reset parameter values, and rename profiles on the local PAD.
When you use Xyplex DEFINE commands, the changes remain in effect until you
reinitialize the system. When you use Xyplex SET commands, the changes take
effect immediately, but remain in effect until you initialize the X.25 Gateway. The
X.25 Gateway Commands Reference Guide describes each of these commands in
detail.
The Xyplex commands that effect profiles and parameters on the local X.25
Gateway PAD are these:
DEFINE /SET [SERVER] X25 PORT port-list DEFAULT INBOUND PROFILE
" profile-name"
0010
73
PAD Parameters
This command changes the default inbound profile for the ports you specify on the
X.25 Gateway. A remote profile in a LAT or Telnet service for specific ports from
another X.25 Gateway, or a profile set on the PAD, takes precedence over the local
X.25 Gateway default inbound profile
DEFINE | SET [SERVER] X25 PORT port-list DEFAULT OUTBOUND PROFILE
" profile-name"
This command changes the default outbound profile for the ports you specify on the
X.25 gateway. A profile in a local LAT or Telnet service for specific ports or a
profile set on the PAD takes precedence or the X.25 Gateway default outbound
profile.
DEFINE/SET [SERVER] X25 PROFILE ["profile-name" | profile-number ] "newprofile-name "
This command changes the name of the profile you specify.
DEFINE /SET [SERVER] X25 PROFILE ["profile-name" | profile-number]
parameter-number parameter-value
This command changes a parameter value in the profile you specify.
Using Local Services to Change Local PAD Profiles
Local services can include a PAD profile for use at the virtual ports you specify
while the service is active. When the service is no longer in use, the profile for
those virtual ports reverts back to the default value. Chapter 3, Sending and
Receiving Calls, describes how to create local services.
An X.25 profile in a LAT or Telnet service takes precedence over the X.25 Gateway
default outbound profile. The following is an example of a LAT service with an
X.25 profile:
Xyplex> set service netlaser ports 10-20 connect action "987654321" x25
profile "hardcopy"
While the LAT service netlaser is active, the default outbound profile for ports 1020 is hardcopy.
An X.25 profile in an X.25 service takes precedence over the X.25 Gateway default
inbound profile.
Xyplex> set service lanprinter x25 enabled x25 address "123456999" ports
70-75 x25 profile "hardcopy"
While the X.25 service lanprinter is active, the default inbound profile for ports 7075 hardcopy.
74
0010
PAD Parameters
Changing Remote Profiles and Parameters
The X.25 Gateway provides three methods for changing the inbound and outbound
profiles of a remote PAD through a local virtual port: through PAD commands,
through Xyplex commands, and through local services. This section describes
each of these methods.
Using PAD Commands
PAD commands can change remote profiles, reset parameters within remote
profiles, and display remote profiles and parameters. When you change a remote
profile with a PAD command, the change takes precedence over any profile or
parameter setting specified in a Xyplex command or a local service. The change
remains in effect until you terminate the virtual circuit. After you terminate the
virtual circuit, the profile reverts to the default with all the original parameter
settings.
These PAD commands effect profiles and parameters on a remote PAD:
RPROF?
Display the profiles on the remote PAD.
RPROF
Change the default outbound profile of the remote PAD.
RPAR?
Display the parameters of the current profile on the remote PAD.
RSET?
Change a parameter in the remote PAD profile and display the new
value.
RSET
Change a parameter in the remote PAD profile and do not display
the new value.
See Chapter 5 for detailed information about each of these commands.
Using Xyplex Commands
Xyplex commands can assign remote profiles to one or more local virtual ports.
The X.25 Gateway sends the profile to the remote PAD when the PSN establishes a
virtual circuit between the X.25 Gateway and a remote PAD. When you use
DEFINE commands, the changes take effect after you initialize the X.25 Gateway.
When you use SET commands, the changes take effect immediately and lasts until
you log out the port or until you reinitialize the X.25 Gateway. The Xyplex X.25
Gateway Commands Reference Guide describes each of these commands in detail.
The following is the syntax for the Xyplex commands that assign a remote profile to
one or more virtual ports.
DEFINE/SET [SERVER] X25 PORT [port-list] REMOTE PROFILE "profile-name"
0010
75
PAD Parameters
This command assigns a remote profile to one or more virtual ports on the local
X.25 Gateway. When a call from the LAN bound for an X.25 address arrives at a
local port with a remote profile, the local X.25 Gateway overwrites the default
inbound profile on the remote PAD with the profile you specify. When a call from
the PSN arrives at a local port with a remote profile, the local X.25 Gateway
overwrites the default outbound profile on the remote PAD with the profile you
specify.
CLEAR [SERVER] X25 PROFILE ["profile-name" | profile-number] parameternumber
This command clears the values of the parameters you specify in a profile. You
can then send the profile to the remote PAD with only those parameters you want to
change.
Using Local Services to Change Remote PAD Profiles
Local services can include remote profiles. The type of service determines whether
the remote profile overwrites the inbound or outbound profile on the remote PAD. A
remote profile in a LAT or Telnet service overwrites the default inbound profile on
the remote PAD while the service is active. A remote profile in an X.25 service
overwrites the default outbound profile on the remote PAD while the service is
active. When you include a remote profile in a service, use the keywords X25
REMOTE PROFILE.
Use the CLEAR SERVER X25 PROFILE command to clear parameters in the
remote profile which have the same values as those that already exist on the remote
PAD.
The following is an example of a LAT service with a remote profile:
Xyplex>> set service accountshost connect action "5673248999"
ports 20-25 x25 remote profile "laserwriter3"
The following is an example of an X.25 service with a remote profile.
Xyplex>> set service remoteprinter2 x25 enabled connect action "connect
LANprinter2" x25 address "908674580" x25 remote profile "quemeprint"
ports 75-78
76
0010
PAD Parameters
Parameter 1
PAD Recall
The PAD Recall parameter determines whether or not a terminal user can initiate
an escape from the PAD data-transfer state or the connection-in-progress state with
a special character. When a user enters the Recall character the PAD returns to
command state, and the user can enter PAD commands.
Value Means
0
PAD recall is not possible.
1
PAD recall is possible using the data-link escape character ^P.
32-126 PAD recall is possible, using an ASCII character corresponding to the
parameter value. Appendix B gives a table of ASCII values.
Example
* set 1:1
*
With the Recall parameter set to 1, recall is possible with the ^P character.
Parameter 2
Echo
The Echo parameter specifies whether or not the PAD returns the characters that it
receives from the terminal. If the device is a video terminal, the characters appear
on the screen with the Echo parameter enabled. If the device is a printer, the
characters print with the Echo parameter enabled.
Value Means
0
1
Disable echo
Enable echo
Example
* set 2:1
*
With the Echo parameter set to 1, the PAD returns characters that it receives from
the terminal.
0010
77
PAD Parameters
Parameter 3
Data Forwarding
The Data Forwarding parameter specifies certain character sets that signal the
PAD to assemble and forward a complete packet sequence as defined in the X.25
standard. The value 0 indicates no data forwarding character.
Value Means
0
No data forwarding character.
1
Alphanumeric characters (A-Z, a-z, 0-9).
2
<CR> character.
4
<ESC>, <BEL>, <ENQ>, <ACK> characters.
8
<DEL>, <CAN>, <DC2> characters.
16
<ETX>, <EOT> characters.
32
<HT>, <LF>, <VT>, <FF> characters.
64
All other ASCII characters in columns 0 and 1 of International Alphabet
Number 5 (IA5) not included in values 0 through 32. (Appendix B lists these
ASCII characters.)
You can combine parameter values to create groups of data forwarding characters,
including these:
Value Means
6
Combined values 2+4: <CR>, <ESC>, <BEL>, <ENQ>, <ACK>.
18
Combined values 2+16: <CR>, <ETX>, <EOT>.
126
Combined values 2+4+8+16+32+64: all characters in columns 0 and 1 of the
IA5, and the <DEL> character.
The CCITT requires support for values of 0, 2, and 126 in all networks. Values 6
and 18 are optional.
Example
* set 3:6
*
With the Data Forwarding parameter set to 6, the PAD assembles and forwards
packets upon receipt of the <CR>, <ESC>, <BEL>, <ENQ>, and <ACK> characters.
78
0010
PAD Parameters
Parameter 4
Idle Timer
The Idle Timer parameter specifies how long the PAD can wait for each successive
character from the terminal before it assembles a packet and sends the packet to the
X.25 network.
You specify values in intervals of one fiftieth (1/50) of a second, which is 20
milliseconds. Whatever value you select, however, can vary by one interval. For
example, if you specify a value of 1 for this parameter (20 milliseconds) the actual
time-out delay may vary between 20 and 40 milliseconds. The average time-out
delay is usually around 30 milliseconds. If you specify a higher value, the
variation is still 20 milliseconds.
Value Means
0
No data forwarding time-out is required.
1-255
A time-out delay, in fiftieths (1/50) of a second, defined by the number you
specify as the value (1-255).
Example
* set 4:1
*
In this example, the idle timer is set to twenty milliseconds (1/50th of a second).
0010
79
PAD Parameters
Parameter 5
Ancillary Device Code
The Ancillary Device Code parameter determines whether or not the PAD can use
certain ASCII control characters to regulate the flow of characters from the
terminal. These characters, DC1 and DC2, indicate whether or not the PAD is
ready to accept characters from the device. DC1 and DC2 are used to switch an
ancillary transmitting device on and off.
The CCITT requires support for this parameter, but it has no effect on a virtual port.
If you enable flow control by setting the parameter value to 1 or 2, the DC1 and DC3
characters can only control the local physical terminal interface, and only if that
physical terminal supports flow control.
Value Means
0
1
2
No use of X-ON (DC1) and X-OFF (DC3).
Use of X-ON and X-OFF in data-transfer state only.
Use of X-ON and XOFF in data-transfer state and in command state.
If the PAD Ancillary Device Code parameter is set to 1, and the PAD sends an XOFF to a terminal which has no support for flow control, the PAD may be able to
store some additional characters from the terminal. The PAD may not be able to
process those characters, however, until flow control is enabled. While it is storing
the extra characters, the PAD may not echo characters back to the terminal, even if
parameter 2, Echo, is enabled.
If the terminal continues to send characters to the PAD after the PAD sends it an XOFF character, the PAD may run out of storage space. When the PAD has no more
storage space for extra characters, it discards any additional characters from the
terminal, and sends the <BEL> character to the terminal whether parameter 2 Echo
is enabled or not.
Example
* set 5:1
*
In this example, the value of the Ancillary Device Code parameter is set to 1: allow
the use of control characters to regulate the flow of data from the asynchronous
device while the PAD is in data-transfer state.
80
0010
PAD Parameters
Parameter 6
Control of PAD Service Signals
The Control of PAD Service Signals parameter specifies the format of the service
signals that the PAD sends to the terminal. The value 0 indicates that the PAD
should not send any service signals to the device. Service signals include the PAD
prompt, carriage returns, and Clear causes, and diagnostic codes. Chapter 5
describes the PAD service signals in detail.
Value Means
0
Do not send service signals to the device.
1
Send all service signals except the PAD prompt (*) service signal in the
standard format.
4
Send the PAD prompt (*) service signal in the standard format.
8-15
Send the service signals in a network-dependent format.
You can combine these parameter values in one PAD command. For example, 5
combines the values 1 and 4, and causes the PAD to send all service signals to the
device, including the PAD prompt, in the standard format.
Example
* set 6:4
*
With parameter 6 set to 4, the PAD prompt appears in standard format (*).
0010
81
PAD Parameters
Parameter 7
PAD Operation on Receipt of Break
The Operation of Receipt of Break parameter specifies how the PAD reacts after it
receives a break signal from the terminal.
Value Means
0
Do nothing.
1
Send an interrupt packet to a packet-mode DTE or another PAD.
2
Reset.
4
Send an "indication of break PAD" message to a packet-mode DTE or
another PAD
8
Escape from data-transfer state.
16
Discard output to the asynchronous device.
You can combine these parameter values in one PAD command. For example, 5
combines the values 1 and 4, and indicates that the PAD should send an interrupt
packet and an "indication of break PAD" message to a packet-mode DTE or
another PAD.
Example
* set 7:4
*
With parameter 7 set to 4, the local PAD sends a message to the remote PAD or X.25
compatible device, such as a packet-mode DTE, when it receives a break signal.
82
0010
PAD Parameters
Parameter 8
PAD Discard
The Discard parameter determines whether or not the PAD can reject the contents
of user sequences in packets upon request. Normally, the PAD would disassemble
the packets into data, and transmit the data to a destination on the LAN.
Value Means
0
Deliver the data to the terminal normally.
1
Discard the output to the terminal.
Example
* set 8:1
*
With parameter 8 set to 1, the PAD discards all incoming data from X.25 callers, so
that the data does not reach the local asynchronous device.
Parameter 9
Padding after <CR>
The Padding after <CR> parameter specifies the number of padding characters
(nulls) that the PAD inserts after a carriage return <CR> in the character stream it
sends to a printing terminal. This value affects the printing mechanism of the
terminal; the appropriate value allows the printing mechanism to function
correctly. Check the documentation for your particular terminal to determine the
correct value for this parameter.
Value Means
0-255
The number of padding characters the PAD will send to the printing device
after it sends a carriage return <CR>.
Example
* set 9:5
*
With parameter 9 set to 5, the PAD inserts 5 nulls into the character stream to the
terminal after it sends a carriage return.
0010
83
PAD Parameters
Parameter 10
Line Folding
The Line Folding parameter specifies how often the PAD inserts carriage returns
in the character stream that it transmits to the terminal. The value of this
parameter specifies the number of graphic characters the PAD can send to the
terminal before it inserts a carriage return.
Value Means
0
No carriage returns. With this parameter set to 0, the PAD does not insert
carriage returns.
1-255
The number of graphic characters per line that the PAD will transmit to the
asynchronous device without inserting a carriage return.
Example
* set 10:80
*
With parameter 10 set to 80,. the PAD transmits 80 characters to the terminal or
printer before it inserts a carriage return.
Parameter 11
Binary Speed
The Binary Speed parameter is a read-only parameter; you cannot change it. This
parameter enables a packet-mode DTE to access the binary speed characteristic of
the asynchronous device, which is known by the PAD.
From the perspective of each virtual port, the binary speed should be set to the data
rate of the terminal or printer that is associated with it. You can only set this
parameter when you initialize the association between the virtual terminal session
with a physical terminal. You cannot change it during the association.
Any new physical device association with a virtual port should reinitialize this
value to the current rate of the physical device. This will only happen if physical
terminal data rate information is available to the PAD software subsystem. If this
information is not available, the PAD will use a default value of 14 (9600 bits-persecond) for this parameter.
Example
* par? 11
11:14
The PAR? command displays the value of parameter 11 as 14, or 9600 bits-persecond, which is a common value for this parameter.
84
0010
PAD Parameters
Parameter 12
PAD Flow Control
The Flow Control parameter determines whether or not a terminal can send flow
control characters to the PAD. These characters, DC1 and DC2, indicate whether or
not the terminal is ready to accept characters from the PAD. DC1 and DC2 are
ASCII characters used to switch an ancillary transmitting device on and off
(Appendix B lists these ASCII characters.).
The CCITT requires support for this parameter, but it has no effect on a virtual port.
If you enable flow control by setting the parameter value to 1, the DC1 and DC3
characters can only control the local physical device interface, and only if that
physical terminal supports flow control.
Value Means
0
1
No use of X-ON (DC1) and X-OFF (DC3).
Use of X-ON and X-OFF for flow control.
If the PAD Flow Control parameter is set to 1, and the PAD receives an X-OFF, the
network may be able to store a full packet level window of information.
Example
* set 12:1
*
With parameter 12 set to 1, the PAD allows the X-ON and X-OFF flow control
characters.
0010
85
PAD Parameters
Parameter 13
Linefeed Insertion After <CR>
The Linefeed Insertion After <CR> parameter specifies whether or not the PAD
inserts a Linefeed character in the character stream to or from the terminal or
printer after each carriage return. This parameter only applies when the PAD is in
data-transfer state.
Value Means
0
1
2
4
Do not insert linefeeds.
Insert a linefeed after each <CR> in the data stream to the terminal.
Insert a linefeed after each <CR> in the data stream from the terminal.
Insert a linefeed after each <CR> in the echo to the terminal.
You can combine these parameter values in one PAD command. For example, 5
combines the values 1 and 4, and indicates that the PAD should insert a linefeed
after each carriage return in the data stream and in the echo to the printer or
terminal.
Example
* set 13:1
*
With parameter 13 set to 1, the PAD does not insert a linefeed character after
carriage returns.
86
0010
PAD Parameters
Parameter 14
Linefeed Padding
The Linefeed Padding parameter specifies how many padding characters (nulls)
the PAD inserts after a linefeed character in the character stream that the PAD
sends to a printer. This value affects the printing mechanism; the appropriate
value allows the printing mechanism to function correctly. The documentation for
your particular printer should have more information about linefeed padding.
Value Means
0-255 The number of padding characters (nulls) that the PAD will send to the
printer after the PAD transmits a linefeed character.
Example
* set 14:5
*
With parameter 14 set to 5, the PAD sends five null characters to the printer after it
receives a linefeed character.
0010
87
PAD Parameters
Parameter 15
PAD Editing
The PAD Editing parameter specifies whether or not you can edit PAD commands
in data-transfer state as well as in the PAD command state. The editing functions
include delete character, delete line, and display line, which you specify through
parameters 16, 17, and 18. Although Recommendation X.3 does not require support
for PAD editing in data-transfer state, editing is always available during PAD
command state. You must set the value of this parameter to 1 if you want specify
values in the PAD editing parameters:
Parameter 16 Character Delete
Parameter 17 Line Delete
Parameter 18 Line Display
The value of parameter 4, Idle Timer, does not change if this parameter is set to 1,
which affects the idle timer.
Value Means
0
No use of editing in the data-transfer state.
1
Use of editing in the data-transfer state. When the value of this parameter
is set to 1, these PAD operations are suspended:
Data forwarding on full packet until the editing buffer is full.
Data forwarding when the idle timer expires.
The X.28 standard defines certain PAD editing service signals which the PAD
sends to the printer or terminal instead of echoing the editing characters.
Parameter 19, Editing PAD Service Signals, controls the content of these editing
service signals.
Example
* set 15:1
*
With parameter 15 set to 1, users can edit PAD commands when the PAD is in datatransfer state.
88
0010
PAD Parameters
Parameter 16
Character Delete
The Character Delete parameter defines a character which causes the PAD to delete
the character it has most recently received from the terminal. The value of
parameter 15, PAD Editing, must be set to 1 to use this parameter in data-transfer
state.
During the data-transfer state of the terminal, the PAD does not assemble the delete
character into the packet that it will transmit to the X.25 network. During the PAD
command state, the PAD does not interpret the delete character as part of the PAD
command that you are editing.
Value Means
0-126
The decimal value of an ASCII character from international alphabet
number 5 (IA5), which will delete the character that the PAD has most
recently received from the terminal. Appendix B lists these characters.
127
The <DEL> character deletes the character that the PAD has most recently
received from the terminal.
Example
* set 16:127
*
With parameter 16 set to 127, the <DEL> character deletes the character that the PAD
has most recently received from the terminal.
0010
89
PAD Parameters
Parameter 17
Line Delete
The Line Delete parameter defines a character which causes the PAD to delete the
line it most recently received from the terminal. The value of parameter 15, PAD
Editing, must be set to 1 to use this parameter in data-transfer state.
If the PAD receives this character when the terminal is in data-transfer state, the
PAD discards all characters being assembled into a packet. If the PAD receives
this character when it is in command state, the PAD discards all characters being
assembled into the PAD command.
Value Means
0-23
The decimal value of an ASCII character from international alphabet
number 5 (IA5), which deletes the line that the PAD has most recently
received from the printer or terminal. Appendix B lists the values for these
characters.
24
The <CAN> character deletes the line that the PAD has most recently
received from the printer or terminal.
25-255 The decimal value of an ASCII character from international alphabet
number 5 (IA5), which deletes the line that the PAD has most recently
received from the printer or terminal. Appendix B lists the values for these
characters.
Example
* set 17:24
*
With parameter 17 set to 24, the <CAN> character deletes the most recently received
line that the PAD has received from the terminal.
90
0010
PAD Parameters
Parameter 18
Line Display
The Line Display parameter defines a character that causes the PAD to display all
the characters it is receiving from the printer or terminal. The value of parameter
15, PAD editing, must be set to 1 to use this parameter in data-transfer state.
If the PAD receives this character in data-transfer state, it sends all the characters
being assembled into a packet to the terminal. The PAD does not assemble the line
display character into the packet that it sends to the network. If the PAD receives
this character in command state, it sends all the characters being assembled into a
PAD command to the printer or terminal. The PAD does not include the line
display character in the PAD command.
Value Means
0-17
The decimal value of an ASCII character from international alphabet
number 5 (IA5) which displays a line of characters from the printer or
terminal.
18
The <DC2> character from IA5 displays a line of characters from the
printer or terminal.
19-255 The decimal value of a character from international alphabet number 5
(IA5) which displays a line of characters from the printer or terminal.
Example
* set 18:18
*
With parameter 18 set to 18, the PAD displays lines when users enter the <DC2>
character.
0010
91
PAD Parameters
Parameter 19
Editing PAD Service Signals
The Editing PAD Service Signals parameter specifies whether or not the PAD
sends editing service signals, or messages, to the terminal when the PAD receives
editing characters.
To use this parameter, the value of parameter 15, PAD Editing, must be set to 1, and
the value of parameter 6, Control of PAD Service Signals, cannot be 0. See Chapter 5
for more information about PAD editing service signals.
Value Means
0
1
2
Do not send editing PAD service signals.
Send editing PAD service signals for printers.
Send editing PAD service signals for video display terminals.
8 and Send editing PAD service signals, using one ASCII character from this
32-126 range of decimal values.
Example
* set 19:1
*
With parameter 19 set to 1, the PAD sends service signals to printers when it
receives editing characters from those printers.
92
0010
PAD Parameters
Parameter 20
Echo Mask
The Echo Mask parameter specifies whether or not the PAD returns, or echoes,
certain characters to the terminal that it receives from that terminal. The
parameter values specify the character or characters you want to suppress, or mask.
The value 0 specifies no echo mask. If you choose not to mask characters, the PAD
echoes all characters it receives from the device.
The value of parameter 2 ,Echo, must be 1 (enabled) to use this parameter.
Value Means
0
No echo mask. If you use this value, the PAD echoes all characters.
1
No echo of the <CR> character.
2
No echo of the <LF> character.
4
No echo of the <VT>, <HT>, and <FF> characters.
8
No echo of the <BEL> and <BS> characters.
16
No echo of the <ESC> and <ENQ> characters.
32
No echo of the <ACK>, <NAK>, <STX>, <SOH>, EOT, <ETB>, and <ETX>
characters.
64
No echo of editing characters as designated by parameter 16 Character
Delete, parameter 17 Line Delete, and parameter 18 Line Display.
128
No echo of all other characters in columns 0 and 1 of international alphabet
5, not listed in values 1, 2, 4, 8, 16, 32, 64, and the character <DEL>.
Appendix B lists these ASCII values.
You can combine these parameter values in one PAD command. For example, 6
combines the values 2 and 4, and causes the PAD not to echo the <LF>, <VT>,
<HT>, and <FF> characters.
Example
* set 20:3
*
With parameter 20 set to 3, the PAD does not echo the carriage return <CR> or
linefeed <LF> characters.
0010
93
PAD Parameters
Parameter 21
Parity Treatment
The Parity Treatment parameter allows the PAD to check parity in the data stream
from the terminal, or generate parity in the data stream to the terminal, or both.
Value Means
0
1
2
No parity checking or generation.
Parity checking.
Parity generation.
You can combine the values 1 and 2 in one PAD command to indicate parity
checking and generation.
Example
* set 21:3
*
With parameter 21 is set to 3, the PAD checks and generates parity in the data
stream from the terminal.
94
0010
PAD Parameters
Parameter 22
Page Wait
The Page Wait parameter determines whether or not the PAD stops sending
characters to the terminal after it transmits a certain number of linefeed
characters to the terminal. The PAD resumes sending characters when one or
more of these conditions exists: the PAD receives a data forwarding condition
from the terminal, the PAD sends the "linefeed delete" service signal to the
terminal, or when the PAD echoes the linefeed character to the terminal. When the
PAD has stopped sending characters to the terminal, the PAD is in a page wait
condition.
The PAD resumes sending characters when it receives a characters if one or more
of these conditions exist:
•
Value Means
0
Disable page wait.
1-255
Enable page wait after the PAD sends the number of linefeed characters to
the terminal that you give as the parameter value (1-255).
If the PSN supports this parameter, the standard requires support for the values 0
and 23. Other values are optional.
Example
* set 22:20
*
With parameter 22 set to 20, the PAD enters a page wait condition after it sends 20
linefeed characters to the terminal.
End of Chapter
0010
95
Chapter 5
Using the X.28 PAD Commands
and PAD Service Signals
This chapter describes the PAD commands and PAD Service Signals. The
commands allow you to establish connections with remote X.25 addresses, set and
view PAD profiles, and send request packets to remote PADs. The commands in
this chapter are compatible with the X.28 standard for PAD commands.
Several of the commands in this chapter set or display PAD parameters and PAD
profiles. They require that you enter profile names, parameter numbers, and
parameter values. Chapter 4 explains more about PAD profiles, parameters, and
parameter values.
Many of these commands generate PAD service signals. Service signals are
messages from the PAD that indicate why a command has succeeded or failed, or
that there is a problem on the X.25 network. The PAD service signals are described
at the end of this chapter.
The PAD commands in this chapter are the following:
CALL
CLR
FACILITIES
FULL
HALF
HELP
INTERRUPT
LISTEN
PAR?
PROF
RESET
RICLR
RPAR?
RPROF
RSET
RSET?
SET
SET?
STATUS
TABS
0010
96
PAD Commands
Obtaining the PAD Prompt
You enter PAD commands from the PAD prompt. How you obtain the PAD prompt
depends on whether you connect to the PAD from a virtual port, or you recall the
PAD to command state during an active virtual circuit.
Connecting to the PAD from a Virtual Port
LAT and Telnet services make connections to the PAD through the virtual ports you
specify in the service. For example, the following service returns the PAD prompt
when you enter it at ports 20-30:
Xyplex> set service pad1 ports 20-30 enabled
To connect to the PAD, enter the service name. When you see the Xyplex status
message indicating that a session has been established, enter the <New Line> or
<CR> key once or twice until the PAD prompt appears:
Xyplex> connect pad1
Xyplex -10- Session 1 to PADCONNECT on node X00A69 established
*
If the connection is successful, the PAD prompt appears. The default PAD prompt
on the X.25 Gateway is an asterisk *. You can change this default with the
DEFINE/SET SERVER X25 PROMPT commands. From the PAD prompt you can
enter PAD commands.
From a Telnet host, you could also connect to the PAD directly, using its Telnet
address and an X.25 port number. After you enter the command, enter the <New
Line> or <CR> key once or twice until the PAD prompt appears:
Xyplex> telnet 140.179.20.1: 2200
*
If the connection is successful, the PAD prompt appears.
Returning the PAD to Command State During a Virtual Call
PAD parameter 1, PAD Recall, determines whether or not you can enter a
predefined recall character to return the PAD to command state while it is in datatransfer state during a virtual call. If this parameter is set to 0, you cannot recall
the PAD to command state. If the parameter is set to 1, you enter the @ character to
recall the PAD. If the parameter is set to any of the values 32-126, you enter a
specified ASCII character to recall the PAD. When you enter the recall character,
the PAD prompt appears and you can enter commands.
0010
97
PAD Commands
Entering PAD Commands
The PAD commands follow the same format as X.25 Gateway commands.
*
PADCOMMAND [keyword] [keyword variable]
You can enter PAD commands in either upper- or lowercase letters.
Abbreviating PAD Commands
You can abbreviate many of the PAD commands to the shortest unambiguous string
of characters that the system can interpret. For example, the FACILITIES
command begins with F, and F is the only character you need to issue the
FACILITIES command. You could also enter FAC or FACIL. The FULL command
also begins with F, so you need to enter at least FU to issue the FULL command so
that the system does not misinterpret it. Each command description indicates
whether or not you can abbreviate it.
98
0010
PAD Commands
CALL
Call an X.25 address
The CALL command sends a call request packet to the remote X.25
address you specify in the command. If the remote device agrees to accept
the call, the X.25 Gateway PAD sends a Call Connected service signal to
the terminal. The PAD is then in data transfer state and you can send
and receive data.
If you do not include an X.25 address in the command, the PAD uses the
last entered address as the default. The ? argument displays the current
default address.
If you want to define per-call facilities for this call, you must do so before
you issue the CALL command. See the FACILITIES command, later in
this chapter, for information on how to assign per-call facilities.
You can also enter an X.25 address at the PAD prompt without using the
CALL command.
Abbreviation
C
Syntax
CALL [?] | [[address][*P | *Duserdata]]
Where
Means
?
Display the current default X.25 address. The default is the
last address entered on this PAD.
address
The 1 to 15 digit X.25 address.
* Puserdata Do not echo the contents of the userdata field on the screen.
The user-data field can include up to 12 characters.
* Duserdata Echo the contents of the userdata field on the screen. The
userdata field can include up to 12 characters.
0010
99
PAD Commands
Examples
1. The CALL command with the ? argument displays the last-entered
X.25 address.
* call ?
* 123654
2. A user calls this address with a LAN destination in the userdata field.
* call 123654*DHost1
Call Connected
3. A user calls an X.25 address without the CALL command.
* 123654
Call Connected
100
0010
PAD Commands
CLR
Send a clear request packet to the remote PAD
The CLR command sends a clear request packet from the local PAD to the
remote PAD. If the request is successful, the PAD terminates the virtual
circuit, the local PAD sends a Clear Confirmation PAD service signal to
the terminal, the PAD prompt appears, and the PAD can accept other
commands. If you clear a PVC with the CLR command, you cannot
reconnect the PVC until you initialize the X.25 Gateway.
To use the CLR command, you must escape from the PAD connection-inprogress state or data-transfer state to recall the PAD to command state.
To do this, enter a predefined character specified by the value of PAD
parameter 1, PAD Recall. This character can be any graphic character or
the data-link escape character <@>, which is hexadecimal 10 in the ASCII
table. If the PAD Recall parameter is set to 0, however, you can not recall
the PAD to command state.
Abbreviation
None
Syntax
CLR
Example
A UNIX user enters the predefined <@> character to escape from the PAD
connection-in-progress state. Once the PAD is in command state, the
user enters the CLR command to end the connection. The PAD issues a
CLR CONF service signal to indicate that the termination request is
successful.
%
<@>
*
* clr
CLR CONF
*
0010
101
PAD Commands
FACILITIES
Specify per-call facilities
The FACILITIES command stores a per-call facilities request field for
use on all future CALL commands. You can also use this command with
the * argument to clear the current facilities request field in the local
PAD. See Chapter 2 for more information on per-call facilities. See The
X.25 Gateway Commands Reference Guide for information about how to
assign per-call facilities to virtual ports through the Xyplex command
interface. Any facilities' values that you set through the PAD take
precedence over values defined through the Xyplex commands.
To set facilities with this PAD command, you need to use the CCITT
standard hexadecimal values for these facilities as variables in the
command. Consult the CCITT standards documentation to obtain these
hexadecimal values.
Abbreviation
F
Syntax
FACILITIES [* | facilities]
Where
Means
*
Clear the current per-call facilities request field in the local
PAD.
facilities
A string of 0 to 63 hexadecimal digits that represents X.2
facilities identifiers and their values.
Example
The FACILITIES command sets a packet size of 256 bytes with the
facilities identifier 420808.
* facilities 420808
*
102
0010
PAD Commands
FULL
Operate in full duplex mode
The FULL command causes the PAD to operate in full duplex mode. This
command has the effect of setting the value of PAD Parameter 2, Echo, to 1
(echo enabled). The PAD operates in full duplex mode until you
terminate the current virtual circuit.
The PAD operates in full duplex mode by default.
Abbreviation
FU
Syntax
FULL
Example
* full
*
0010
103
PAD Commands
HALF
Operate in half duplex mode
The HALF command causes the PAD to operate in half duplex mode.
This command has the effect of setting the value of Parameter 2 Echo to 0,
(no echo). The PAD operates in half duplex mode until you terminate this
virtual circuit.
You can use the command options to echo specific characters, and to
display the characters that the PAD echoes in half duplex mode.
Abbreviation
HA
Syntax
HALF [*] | [[-] ch1, ch2, . . . chn]]
Where
Means
*
Display the characters, if any, that the PAD echoes in halfduplex mode.
chn
A number from IA5 which represents an ASCII character
that the PAD will echo in half-duplex mode.
-
Do not echo the characters you specify with a number from
IA5 in half-duplex mode.
Examples
1 . This command enables half-duplex mode and displays the message
that the PAD does not echo any characters.
* half *
will echo:
none
*
2. This command enables half-duplex mode and specifies that the PAD
will echo the ! character, represented by the number 3.
* half 3
will echo 3
*
104
0010
PAD Commands
HELP
Display the list of PAD commands
The HELP command displays the list of PAD commands and variables.
The X.25 Gateway may not support all of the options for the commands in
the display. The following example shows a help display which includes
the command options that the X.25 Gateway supports.
Abbreviation
H
Syntax
HELP
Example
* help
CALL [?]|[[address] [*P|*Duser-data]]
CLR
FACILITIES [*|facilities]
FULL
HALF [*] | [[-] ch1, ch2, . . . chn]]
HELP
INTERRUPT
LISTEN [ADDR=address|DATA=user-data]
PAR? [ref1,[ref2,...,refn]]
PROF [?|profile]
RESET
RICLR
RPAR? [ref1[,ref2,...,refn]]
RPROF [profile|?]
RSET [ref1:val1[,ref2:val2,...,refn:valn]]
RSET? [ref1:val1,[,ref2:val2,...,refn:valn]]
SET [ref1:val1[,ref2:val2,...,refn:valn]]
SET? [ref1:val1[,ref2:val2,...,refn:valn]]
STATUS
TABS {LCL tab-num} {REM tab-num} {EXP exp-num}
*
0010
105
PAD Commands
INTERRUPT
Send an interrupt packet to the remote PAD
The INTERRUPT command signals the local PAD to send an interrupt
packet to the remote PAD. To use the INTERRUPT command, you must
escape from the PAD connection-in-progress state or data-transfer state to
recall the PAD to command state. To do this, enter a predefined character
specified by the value of PAD parameter 1, PAD Recall. This character
can be any graphic character from the ASCII table in Appendix B. If the
PAD recall parameter is set to 0, however, you can not recall the PAD to
command state.
After you enter the INTERRUPT command, the PAD reestablishes the
X.25 session.
Abbreviation
I
Syntax
INTERRUPT
Example
A UNIX user enters the <@> character to escape from the PAD connectionin-progress state. Once the PAD is in command state, the user enters the
INT command. the PAD sends an interrupt packet, which causes the
remote PAD to send an interrupt-confirmation packet. The PAD then
resumes the X.25 session.
%
<@>
*
.
.
* int
%
106
0010
PAD Commands
LISTEN
Specify a listen address for an incoming call
The LISTEN command specifies a listen address or user-data for the
virtual port associated with this PAD. If the listen address or user data
you specify in this command matches that of an incoming call, the PAD
accepts the call. If the listen address or user data does not match, the PAD
rejects the call. The listen address or user-data remains in effect until
you change it.
A listen address specified on the PAD takes precedence over a listen
address specified in an X.25 service. See Chapter 3 for information about
specifying a listen address in an X.25 service.
Abbreviations
L A D
Syntax
LISTEN [ADDR=address | DATA=user-data]
Where
Means
address
A 1 to 15 digit X.25 address.
user-data
0 to 12 ASCII characters that represent information from the
remote PAD.
Examples
1. The LISTEN command specifies that the local PAD can accept calls at
this virtual port from a resource with the address 1253698.
* listen address=1253698
*
2. The LISTEN command specifies that the PAD can accept calls at this
virtual port from a resource with the characters xuser123 as the last seven
characters in the user data field.
* listen data=xuser123
*
0010
107
PAD Commands
PAR?
Display parameter values of the default outbound profile of the local PAD
The PAR? command displays the parameter values of the outbound profile
of the local PAD. If you enter the PAR? command without arguments, the
PAD displays all parameter values for the profile. You can also specify
values for individual parameters with parameter numbers through the ref
argument.
Abbreviation
none
Syntax
PAR? [ref1,[ref2, . . .refn]]
Where
Means
ref
A valid X.3 parameter number. X.3 parameters are
numbered from 1 to 22.
Example
The PAR? command has no arguments. The PAD displays the values of
all the parameters in the inbound profile for the current port.
* par?
1:64, 2:1, 3:127, 4:2, 5:0, 6:5, 7:2, 8:0, 9:0, 10:0,
11:14, 12:1, 13:4, 14:0, 15:0, 16:127, 17:24, 18:18, 19:2,
20:0, 21:3, 22:0
*
108
0010
PAD Commands
PROF
Change the default outbound profile of the local PAD
The PROF command changes the default outbound profile of the local
PAD. If you use the ? argument with this command, the PAD displays the
name of the default outbound profile for the virtual port, and the names of
all other available profiles. If you do not use an argument, the PAD
displays only the default outbound profile for the virtual port.
Abbreviation
none
Syntax
PROF [? | profile]
Where
Means
?
List all available profile identifiers.
profile
The name of an available profile. The X.25 Gateway
includes forty profiles with names that you can change. The
profile identifiers that come with the X.25 Gateway are these:
HOST
CC_SSP
CC_TSP
CRT
HARDCOPY
CRT_NOE
XYPLEX7. . . XYPLEX40
0010
109
PAD Commands
Examples
1. The PROF ? command displays the current and available profiles on
the X.25 Gateway PAD.
* prof ?
Profile:
CRT_NOE
Permanent:
HOST
CC_SSP
CC_TSP
CRT
HARDCOPY
CRT_NOE
XYPLEX7
XYPLEX8
XYPLEX9
XYPLEX10
XYPLEX11
XYPLEX12
XYPLEX13
XYPLEX16
.
.
.
XYPLEX31
XYPLEX32
XYPLEX33
XYPLEX34
XYPLEX35
XYPLEX36
XYPLEX37
XYPLEX38
XYPLEX39
XYPLEX40
USER DEFINED:
*
2. The PROF command sets the PAD profile to CRT.
* PROF CRT
*
110
0010
PAD Commands
RESET
Send a reset packet to the remote PAD
The RESET command sends a reset-request packet from the local PAD to
the remote PAD to resynchronize the virtual circuit. The reset packet
from the local PAD has the cause code set to zero (DTE originated), and the
diagnostic code set to zero (no additional information). The reset request
may cause the PAD to discard outstanding data packets.
The packets sent and packets received sequences within the session are
reset to 0 after you enter this command.
Abbreviation
none
Syntax
RESET
Example
The <@> character recalls the PAD to command state so that the user can
issue the RESET command.
% <@>
* reset
*
0010
111
PAD Commands
RICLR
Send an invitation-to-clear packet to the remote PAD
The RICLR command signals the local PAD to send an invitation-toclear packet to the remote PAD. This causes the remote PAD to flush any
outstanding data it has received to the remote DTE, and then to issue a
clear request packet. When the remote PAD receives an invitation to
clear packet, the PAD may wait to issue the clear request packet,
depending on the application at the remote resource.
Abbreviation
RI
Syntax
RICLR
Example
* riclr
*
112
0010
PAD Commands
RPAR?
Display the default inbound profile parameter values of the remote PAD
The RPAR? command displays the parameter values in the default
inbound profile of the remote PAD. You can specify individual
parameters or enter the RPAR? command without arguments to display
all parameter values.
Abbreviation
RPA
Syntax
RPAR? [ref1,[ref2, . . . ,refn]]
Where
Means
ref
A valid X.3 parameter number. X.3 parameters are
numbered from 1 to 22.
Example
The RPAR? command specifies parameters 15, 16, and 17 as arguments.
The remote PAD displays the these parameters with their values in the
default inbound profile.
* rpar? 15, 16, 17
par 15:1, 16:127 , 17:24
*
0010
113
PAD Commands
RPROF
Change the default inbound profile of the remote PAD
The RPROF command changes the default inbound profile of the remote
PAD. Before you attempt to change a remote profile, you may want to
check the list of profile identifiers on the remote PAD with the ? argument.
Abbreviation
RPR
Syntax
RPROF [profile | ? ]
Where
Means
profile
The name of an available profile. The MAXserver X.25
Gateway includes forty profiles with names that you can
change. The profile identifiers that come with the X.25
Gateway are these:
HOST
CC_SSP
CC_TSP
CRT
HARDCOPY
CRT_NOE
XYPLEX7 . . . XYPLEX40
The profile identifiers on the remote PAD may be different.
?
114
Display the current profile identifier and a list of available
profile identifiers.
0010
PAD Commands
Examples
1. The RPROF ? command displays the default inbound profile and the
available profiles on the remote PAD, which is part of another X.25
Gateway.
* rprof ?
Profile:
CRT
Permanent:
HOST
CC_SSP
CC_TSP
CRT
HARDCOPY
CRT_NOE
XYPLEX7
XYPLEX8
XYPLEX9
XYPLEX10
XYPLEX11
XYPLEX12
XYPLEX13
XYPLEX16
.
.
.
XYPLEX31
XYPLEX32
XYPLEX33
XYPLEX34
XYPLEX35
XYPLEX36
XYPLEX37
XYPLEX38
XYPLEX39
XYPLEX40
*
2. The RPROF command changes the profile on the remote PAD to
CRT_NOE.
* rprof crt_noe
*
0010
115
PAD Commands
RSET
Set the parameter values in the default inbound profile of the remote PAD
The RSET command changes the parameter values in the inbound profile
of the remote PAD, but does not display them.
Abbreviation
none
Syntax
RSET [ref1:val1[,ref2:val2,...,refn: valn]]
Where
Means
ref
A PAD parameter number. The X.3 standard defines
twenty-two PAD parameters, numbered from 1 to 22. You
can specify up to twenty-two parameter numbers in the RSET
command.
val
An X.3 PAD parameter value. Parameter values are
decimal numbers that represent different information
associated with each parameter. You can specify only one
value for each parameter.
Separate parameter numbers and parameter values in the command line
with a colon :
Example
This command sets Parameter 2, Echo, to 0: do not echo characters on the
terminal. It sets Parameter 3, Data Forwarding, to 2: forward data on
receipt of a carriage return <CR> character.
* rset 2:0, 3:2
*
116
0010
PAD Commands
RSET?
Change the parameter values in the profile of the remote PAD and display the values
The RSET? command changes the parameter values in the default
inbound profile of the remote PAD and displays those values. If you have
a video terminal, the PAD displays the values on the screen. If you have a
printing terminal, the PAD prints the parameter values.
Abbreviation
none
Syntax
RSET? [ref1:val1,[ref2:val2,...refn: valn]]
Where
Means
ref
An X.3 PAD parameter number. The X.3 standard defines
twenty-two PAD parameters, numbered from 1 to 22. You
can specify up to twenty-two parameter numbers in the
RSET? command.
val
An X.3 PAD parameter value. Parameter values are
decimal numbers that represent different information
associated with each parameter. You can specify only one
value for each parameter.
Separate parameter numbers and parameter values in the command line
with a colon :
Example
* rset? 2:0, 3:2
PAR 2:0, 3:2
*
This command sets Parameter 2, Echo, to 0: do not echo characters on the
terminal. It sets Parameter 3, Data Forwarding, to 2: forward data on
receipt of a carriage return <CR> character.
0010
117
PAD Commands
SET
Change the parameter values in the default outbound profile of the local PAD
The SET command changes parameter values in the outbound profile of
the local PADto the values you specify, but does not display them.
Abbreviation
none
Syntax
SET [ref1:val1,[ref2:val2,...refn: valn]]
Where
Means
ref
An X.3 PAD parameter number. The X.3 standard defines
twenty-two PAD parameters, numbered from 1 to 22. You
can specify up to twenty-two parameter numbers on the
command line
val
An X.3 PAD parameter value. Parameter values are
decimal numbers that represent different information
associated with each parameter. You can specify only one
value for each parameter on the command line.
Separate parameter numbers and parameter values in the command line
with a colon :
Example
This command sets Parameter 2: Echo, to 0 - do not echo characters on the
terminal. It also sets Parameter 3, Data Forwarding, to 2: forward data
on receipt of a carriage return <CR> character.
* set 2:0,3:2
*
118
0010
PAD Commands
SET?
Change the parameter values in the profile of the local PAD and display the values
The SET? command changes the parameters values in the outbound
profile of the local PAD and displays those values. If you have a video
terminal, the PAD displays the values on the screen. If you have a
printing terminal, the PAD prints the parameter values.
Abbreviation
none
Syntax
SET? [ref1:val1,[ref2:val2,...refn: valn]]
Where
Means
ref
An X.3 PAD parameter number. The X.3 standard defines
twenty-two PAD parameters, numbered from 1 to 22. You
can specify up to twenty-two parameter number-parameter
value pairs on the command line.
val
An X.3 PAD parameter value. Parameter values are
decimal numbers that represent different information
associated with each parameter. You can specify only one
value for each parameter on the command line.
Separate parameter numbers and parameter values in the command line
with a colon :
Example
This command sets Parameter 2, Echo, to 0: do not echo characters on the
terminal. It sets Parameter 3, Data Forwarding, to 2: forward data on
receipt of a carriage return character.
* set? 2:0,3:2
PAR 2:0,3:2
*
0010
119
PAD Commands
STATUS
Display status information about the current virtual call
The STATUS command displays information about the status of the
current virtual port. The FREE status messages indicates that no virtual
circuit currently exists. The ENGAGED status message indicates that a
virtual circuit does currently exist. In addition to the status, the message
includes the transmission speed of the link, and the logical channel
number in use at a port with an active virtual circuit. See the section on
PAD service signals at the end of this chapter more information.
Abbreviation
S
Syntax
STATUS
Example
1 . The PAD responds to the STATUS command with the following
information at port 40, where no virtual circuit currently exists..
* status
FREE:
PORT #40 / 9600 BAUD
2. The PAD responds to the STATUS command with the following
information at port 20, where a virtual circuit is active.
* status
ENGAGED:
120
PORT #20 / LC #36 / 9600 BAUD
0010
PAD Commands
TABS
Set and read the tab parameter on the local PAD
The TABS command sets and reads three nonstandard parameter values
on the local Xyplex PAD. These values affect the number of spaces the
PAD includes in a tab in incoming data and outgoing data. You can enter
this command without arguments to read the values without setting them.
Abbreviation
TLRE
Syntax
TABS [LCL tab-num] [REM tab-num] [EXP exp-num]
Where
Means
LCL
Expand tabs to the number of spaces in the tab-num variable
for echo and incoming data. The tab-num variable is a
number from 0 to 16. The exp-num variable must be set to 1
in the EXP argument for this value to take effect.
REM
Expand tabs to the number of spaces in tab-num for outgoing
data. The tab-num variable is a number from 0 to 16. The
exp-num variable must be set to 1 in the EXP argument for
this value to take effect.
EXP
Enable or disable expansion of tabs. The exp-num variable
can have these values:
1
0
Enable tab expansion.
Disable tab expansion.
Example
The TABS command enables the expansion of tabs for echo and incoming
data to 10 spaces and outgoing data to 10 spaces.
* tabs exp 1 lcl 10 rem 10
*
0010
121
PAD Commands
X.29 PAD Service Signals
From time to time, the local PAD sends informational and error messages to your
terminal. These messages are PAD Service Signals, and are defined in CCITT
recommendation X.28 as part of the standard language between the end user and
the PAD. Some of these signals are a direct response to PAD commands, while
others may indicate some problem on the network. This section describes the
CCITT X.28 PAD Service Signals in alphabetical order, beginning with symbols.
122
Signal
Means
*
The default local PAD prompt.
backspace-spacebackspace
Character delete indication for video terminals.
Repetition of this sequence may indicate line deletion.
/
Character delete indication for printing terminals.
return-linefeed
Acknowledgment PAD service signal. This sequence can
indicate the end of a service signal or that the PAD
received the last command you entered.
CLR cause
Clear indication service signal. The PAD sends the CLR
signal when the PSN clears a virtual call or when an
attempt to make a call fails. The value of the cause field
indicates why the PSN cleared the connection. Standard
values for cause are the following:
DER
Out of Order. The number you called is out of order
or not available. It may or may not be available at a
later time.
DTE
DTE Clearing. The remote DTE cleared the call.
ERR
Local procedure error. The PAD detected an error
from the local DTE.
INV
Invalid facility request. The calling DTE requested
an incorrect or unsupported facility. See Chapter 2
for a list of valid X.2 facilities that the X.25 Gateway
supports. Check with your local PSN administration
for a list of facilities that the PSN supports.
0010
PAD Commands
Signal
CLR CONF
0010
Means
NA
Access barred. Something is preventing a
connection between the calling DTE and the called
DTE, such as an incompatible closed user group
(CUG).
NC
Network Congestion. The call cleared because of
temporary network congestion or network faults. If
you made the call through an automatic connection,
the local PAD attempts another call automatically.
If you made the call from the PAD with a CALL
command, you must attempt the call again.
NP
Not obtainable. The X.25 address you called was out
of the number plan or unassigned. Check that you
are calling the correct X.25 address.
OCC
Number busy. The remote DTE is engaged in
another call, and cannot accept the incoming call.
RNA
Reverse charge acceptance not subscribed. The
remote DTE does not subscribe to the reverse charge
acceptance facility.
RPE
Remote procedure error. The remote PAD detected a
procedure error caused by the remote DTE, and
cleared the connection.
Clear confirmation service signal. The local PAD
sends the CLR CONF signal to your terminal after it
sends a clear request packet to the remote PAD and the
remote PAD has returned a clear confirmation packet.
123
PAD Commands
124
Signal
Means
DTE address
[FAC:facilities] COM
[P|Duserdata
Indication of an incoming call. This message
includes information about an incoming call from a
remote DTE. The address field is the Internet address
of the remote DTE, the facilities field contains user
subscription facilities for this call, and the user-data
field contains up to 12 characters of data, such as a
LAN address.
[DTE address] [FAC:
facilities] COM
Call connected service signal. The information in
this signal appears after a remote DTE receives and
accepts a call from the local DTE. The address field is
the X.25 address of the remote DTE. The facilities field
contains the values from the call accepted packet,
although they may be different from those in the
connection request if facilities negotiation has
occurred.
ENGAGED | FREE
Response to PAD STATUS command. ENGAGED
indicates the presence of an established call, and
FREE indicates no established call.
ERR
Error service signal. This signal indicates that the
PAD command you entered was incorrect. Check the
syntax of the command and reenter it.
GCOM PAD version:
ASYNC PORT # port, baud
rate BAUD
PAD identification service signal. The PAD sends
this signal to identify itself to the local DTE. The
syntax of this signal is specific to each PAD; the syntax
shown here is the default version for this PAD. The
network administrator may customize the syntax for
this message with the DEFINE/SET SERVER X25
WELCOME command.
PAGE
Page wait condition.
0010
PAD Commands
Signal
Means
TRANSFER DTE address
facilities userdata
DTE reselection indication. This signal indicates
that the PAD is selecting an alternate DTE to receive
the call. The DTE address field indicates the alternate
address, the facilities field lists the facilities
associated with this DTE, and the userdata field
contains the data for the call.
PAR ref1:val1 |
INV,[ref2:val2 |
INV,...,refn:valn | INV]
Response to SET and SET? PAD commands. The PAD
responds with this signal when you specify invalid
parameter values in the ref and val fields of the SET
and SET? commands. See Chapter 4 for a list of valid
CCITT X.3 parameters and values.
RESET cause diagnostic
code
Reset service signals. The PAD sends a reset signal to
the local DTE when a packet reset occurs. The value in
the cause field indicates the cause of the reset. The
following are the standard reset cause values:
Value Means
DTE
ERR
NC
RPC
The remote DTE has reset the virtual call.
A local procedure error caused the reset.
Network congestion caused the reset.
A remote procedure error caused the reset.
The values in the diagnostic code field, specified in ANNEX
E to CCITT recommendation X.25, fall into these categories:
Value Means
0
16-31
32-47
48-63
64-79
80-95
96-111
112-127
128-255
No additional information.
Invalid packet type.
Packet not allowed.
Timer expired.
Problems with call setup, call clearing, or
call registration.
Miscellaneous.
Not assigned.
International problems.
Reserved for network specific diagnostics
(not all or character delete indication).
End of Chapter
0010
125
Chapter 6
Basic Troubleshooting
This chapter describes several problems that sometimes occur while using the X.25
Gateway, and some possible solutions to them. This chapter includes these
sections:
•
Status Problems with the X.25 Levels
If you cannot attempt to make a virtual call, a hardware problem might exist at
level 1, or an incorrect parameter setting might exist at level 2 or 3. Refer to this
section if you cannot attempt a virtual call.
•
Conditions that prevent virtual calls
If you attempt to make a virtual call, but a Clear Cause and Diagnostic code appear
on your terminal, refer to this section.
•
Incorrect parameter settings
If you have established a virtual circuit, but notice slow system response time or that
the data you send or receive is incomplete, a problem might exist with one or more
PAD parameter settings. Refer to this section if you suspect a problem with PAD
parameters.
Status Problems with the X.25 Levels
When all three X.25 levels function correctly, the "State" line of the Show Server
X25 Status display indicates that all three levels are "Up:"
State:
Line Up/ Frame Up/ Packet Up
When all three layers are "Up," you can attempt virtual calls. If any of these levels
are "Down," however, a problem exists, you cannot make virtual calls. The
following sections describe some of the possible conditions at each of the three X.25
levels that can prevent them from being "Up," and what you can do to fix them.
Level 1 Problems
A problem at level 1, the physical layer, is a hardware problem and affects the status
of all three X.25 levels. If you observe a status such as this: Line Down/ Frame
Down/ Packet Down, assume a level 1 problem before you check the other levels.
0010
126
Troubleshooting
To determine the source of the problem, first check that the hardware is properly
installed. If the X.25 Gateway is a 6625 card, be sure that is properly seated in the
chassis.
Next, check the status lights on the front panel of the 6625 card or the 6025 standalone
unit. Figure 6-1 shows the status lights on a 6625 card as they appear when level 1 is
up, and 6-2 shows the status indicators on a 6025 card when level 1 is "Up."
X25 Gateway
Card
STATUS
CABLE
V35
422
Cable status
423
LINK
RCK
TCK
External Clocking status
DTR
DSR
DCD
Modem Control Status
RTS
CTS
RNG
Figure 6-1. The Status Lights on a 6625 Card
0010
127
Troubleshooting
LINK
RCK
T C K DTR
External Clocking status
DSR
D C D R T S C T S DAT
Modem Control Status
Figure 6-2. The Status Indicators on a 6025 Standalone Unit
Cable status
The cable status on the 6625 card indicates the type of cable between the X.25
Gateway and the attached device, in this case 423. If no cable lights appear, check
that the cable is plugged in, and that you are using the correct cable. If the cable is
not plugged in, no lights appear on the card or the standalone unit.
External Clocking Status
The X.25 Gateway requires an external clock, so the attached device must provide
the clock. If the clock is missing, the RCK and TCK lights do not appear. Check
that the attached device provides the clock.
Modem Control status
When X.25 is enabled and the network is communicating with the X.25 Gateway,
all modem control lights appear except RNG on the 6625 card and DAT on the 6025
standalone unit. If DTR and RTS are lit, but other modem status lights are not lit,
check that X.25 is enabled on the X.25 Gateway. X.25 communication is always
enabled in the permanent database, but you can enable or disable it in the
operational database with the SET SERVER X25 [ENABLED/DISABLED]
command.
After you change any hardware settings on the card or the standalone unit,
reinitialize the X.25 Gateway and view the Show Server X25 Status display.
Correcting a level 1 problem can cause all three levels to appear "Up." If level 2
and level 3 are still down, check the level 2 parameter settings.
Level 2 and Level 3 Problems
A problem at level 2, the frame layer, affects the status of the packet layer as well. If
you observe a status such as this: Line Up/ Frame Down/ Packet Down, check
the level 2 parameter settings first. These include the error recovery timers (T1,
128
0010
Troubleshooting
T2, T3), the retransmission attempt counter (N2), the Extended Frame Sequence
Numbering facility, and the Frame Layer window size. The defaults for these
facilities and parameters are usually appropriate. Check with the PSN
administration to determine if you have the correct level 2 and level 3 settings.
The setting of the level 3 OPMODE characteristic must be correct, or you cannot
make virtual calls. The default is a DTE. The settings for the user facilities and
logical channel numbers at level 3 must agree with those that the PSN
administration supports. These do not affect the level 3 status, although they do
prevent you from establishing a virtual circuit. If you have enabled the level 2
Extended Frame Sequence Numbering facility, be sure you have enabled the level 3
Extended Packet Sequence Numbering facility as well.
Conditions That Prevent Virtual Circuits
When the status of all three X.25 levels is "Up," a call request can still fail for
certain reasons. The PSN can reject a call request packet, or the local DTE/DCE
interface may not agree on packet sizes or user facilities. When a call request
fails, the X.25 interface returns two messages codes to the caller: a Clear Cause and
a Diagnostic code. Most of the time, you can correct the problem once you determine
the reason for the failure from these codes. The codes appear in the following
format:
CLR CAUSE: (0x# #), DIAGNOSTIC (0x# #)
where 0x indicates that the following number is a hexadecimal value and # # is a
hexadecimal error code.
Table 6-1 lists the hexadecimal values for clear causes and their meanings. Table
6-2 lists the hexadecimal values for the diagnostic codes and their meanings. Use
these tables to determine the cause of the failure.
For example, the X.25 interface returns the following Clear Cause and Diagnostic
codes if you call an incorrect X.25 address when the X.25 Gateway is configured as
a DTE:
CLR CAUSE: UNRECOGNIZED (0x0D), DIAGNOSTIC: (0x31)
0010
129
Troubleshooting
The Clear Cause is 0D, which Table 6-1 lists as "Not obtainable," indicates that the
network did not locate the X.25 address. The Diagnostic code is 31, which Table 6-2
lists as "Timer expired for incoming call." This indicates that the network kept
looking for the address until the DCE T11 timer. To correct this problem, check the
valid X.25 addresses available on the network, and use a correct address. If you
make a call with a facility enabled that the network does not support, the PSN
returns a Clear cause such as "Reverse charging acceptance not subscribed," or
"Fast select acceptance not subscribed."
Table 6-1. Clear Cause Codes
Hex
Decimal
Clearing Causes
00
00
DTE originated
01
01
Number busy
03
03
Invalid facility request
05
05
Network congestion
09
09
Out of order
0B
11
Access barred
0D
13
Not obtainable
11
17
Remote procedure error
13
1
Local Procedure Error
15
21
RPOA out of order
19
25
Reverse charging acceptance not subscribed
21
33
Incompatible destination
29
41
Fast Select Acceptance not subscribed
39
57
Ship absent
7B
123
Cleared by local packet level
7C
124
Restart received
7D
125
X.25 link down
89
137
Out of order (host restart of svc)
93
147
Local procedure error
Registration confirmation causes
(continues)
130
0010
Troubleshooting
Table 6-1. Clear Cause Codes (continued)
03
03
Invalid facility request
05
05
Network congestion
13
19
Local procedure error
7F
127
Registration / cancellation confirmed
Resetting causes
00
00
DTE originated
01
01
Out of order
03
03
Remote procedure error
05
05
local procedure error
07
07
Network congestion
09
09
Remote DTE operational
0F
15
Network operational
11
17
Incompatible destination
1D
29
Network out of order
7B
123
Reset by local packet level
81
129
Out of order (host restart of PVC)
85
133
Local procedure error
Restarting causes
0010
01
01
Local procedure error
03
03
Network congestion
07
07
Network operational
7F
127
Registration / cancellation confirmed
81
129
Network operation (Link came up)
87
135
Local procedure error
131
Troubleshooting
Table 6-2. CCITT Diagnostic Codes
Hex
Decimal
CCITT Diagnostic Codes
00
00
No additional information
01
01
Invalid P(S)
02
02
Invalid P(R)
10
16
Packet type invalid
11
17
For state r1
12
18
For state r2
13
19
For state r3
14
20
For state p1
15
21
For state p2
16
22
For state p3
17
23
For state p4
18
24
For state p5
19
25
For state p6
1A
26
For state p7
1B
27
For state d1
1C
28
For state d2
1D
29
For state d3
20
32
Packet not allowed
21
33
Unidentifiable packet
22
34
Call on one-way logical channel
23
35
Invalid packet type on a permanent virtual circuit
24
36
Packet on unassigned logical channel
25
37
Reject not subscribed to
26
38
Packet too short
27
39
Packet too long
28
40
Invalid general format identifier
29
41
Restart or registration packet with non-zero LCN
2A
42
Packet type not compatible with facility
(continues)
132
0010
Troubleshooting
Table 6-2. CCITT Diagnostic Codes (continued)
0010
Hex
Decimal
CCITT Diagnostic Codes
2B
43
Unauthorized interrupt confirmation
2C
44
Unauthorized interrupt
2D
45
Unauthorized reject
30
48
Timer expired
31
49
For incoming call
32
50
For clear indication
33
51
For reset indication
34
52
For restart indication
40
64
Call set-up, call-clearing, or registration problem
41
65
Facility/ registration code not allowed
42
66
Facility parameter not allowed
43
67
Invalid called address
44
68
Invalid calling address
45
69
Invalid facility/registration length
46
70
Incoming call barred
47
71
No logical channel available
48
72
Call collision
49
73
Duplicate facility requested
4A
74
Non-zero address length
4B
75
Non-zero facility length
4C
76
Facility not provided when expected
4D
77
Invalid CCITT-specified DTE facility
50
80
Miscellaneous
51
81
Improper cause code from DTE
52
82
Not aligned octet
53
83
Inconsistent Q bit setting
133
Troubleshooting
Problems caused by Incorrect Parameter Settings
If you successfully establish a virtual circuit, but the data you receive is incomplete,
appears missing, or arrives very slowly, the parameter settings on the PAD of the
X.25 Gateway virtual port or the remote PAD may be incorrect. This section
describes several parameters that can cause common problems, the symptoms of
those problems, and some possible ways to solve them.
You can use PAD commands or Xyplex commands to view the parameter settings of
a particular profile.
PAD commands:
PAR?
Displays the parameter settings of the default outbound profile of the
local PAD.
RPAR?
Displays the parameter settings of the default inbound profile of the
remote PAD.
Xyplex command:
SHOW/LIST SERVER X25 PORT ALTERNATE CHARACTERISTICS
This command shows the parameter settings of the profile currently in use at the
port during an active virtual circuit. If a call from the PSN established the virtual
circuit, the display shows an inbound profile. If a call from the LAN established the
virtual circuit, the display shows an outbound profile.
Parameter 3 Data Forwarding
Parameter 3, Data Forwarding, specifies certain character sets that signal the PAD
to assemble and forward a packet sequence to the network. This parameter is
sometimes set to 127, which specifies the all characters cause data forwarding,
because this setting can improve character turnaround time on the Gateway. This
may degrade throughput, however, because the PAD sends so many very small
packets out on the virtual circuit.
Other ways to improve throughput include the following:
134
•
Set parameter 3 to 0 and parameter 4, Idle timer, to a value such as 2 (see also
the note on Idle Timer Considerations, later in this section).
•
Decrease the value of the LAT circuit timer, and increase the value of the
PORT TYPEAHEAD SIZE and the values of the X.25 DEFAULT PACKET
SIZE and MAX PACKET SIZE.
0010
Troubleshooting
Parameter 4 Idle timer
The value of PAD Parameter 4, Idle Timer, determines how many intervals the
idle timer will wait to receive characters from the terminal before it assembles the
characters into a packet and sends the packets to the network. The idle timer
parameter in the X.25 Gateway is set to intervals of 20 milliseconds by default. If
you reset this to a value that is too low, however, it may affect the data flow in the
following ways.
•
A low Idle Timer value can cause unacceptably small packets, depending on the
link speed. If this is the case, you may notice slow system response time and
"choppy" data.
•
A high Idle Timer value can cause the PAD to use excessive amounts of memory.
In extreme cases, the X.25 Gateway may run out of memory entirely.
If you notice these problems, you can increase the value of the Idle Timer parameter.
End of Chapter
0010
135
Appendix A
X.25 Gateway Status and Error Messages
The X.25 Gateway displays messages that describe the status of operations and
indicate when errors occur. This appendix lists these status and error messages.
The X.25 Gateway software displays status and error messages in one of two
formats:
Xyplex -n n n- Message text
Message text
The three digit status or error code (n n n) always appears when you are logged onto
the remote console port (Port 0). Display of the three digit status or error code at Port
1 is controlled by the PORT MESSAGE CODES characteristic.
Xyplex -801- Facilities Field is full for port n
There is no more room in the facilities field for this port. To add to or change the
facilities for this port, you must first clear the facilities field with the DEFINE/SET
SERVER X25 port-list FACILITY NONE command.
Xyplex -802- Not valid for DCE
The X.25 Gateway has been configured as a logical DCE with the DEFINE/SET X25
LEVEL_3 OPMODE command. The feature you specified has no meaning for a
DCE.
Xyplex -803- Not valid for DTE
The X.25 Gateway has been configured as a logical DTE, which is the default
setting for the Opmode characteristic. You can change the Opmode with the
DEFINE/SET X25 LEVEL_3 OPMODE command. The feature you specified has no
meaning for a DTE.
Xyplex -804- NUI must be Alphanumeric Text
The information you transmit using the NUI facility must include alphanumeric
characters only.
Xyplex -805- NUI String n is Too Long
0010
136
X.25 Gateway Status and Error Messages
The number of alphanumeric characters in an NUI string must not exceed twelve.
Xyplex -806- RPOA Must Be Numeric
The RPOA gateway identifier always consists of numeric characters only.
Xyplex -807- Welcome Must Be Alphanumeric Text
The characters in the X.25 Gateway welcome string must include only
alphanumeric characters.
Xyplex -809- Address is Too Large
An X.25 address must be between 1 - 15 digits long.
Xyplex -810- Welcome String is Too Long
The text in the welcome string for the X.25 Gateway cannot exceed 79 ASCII
characters.
Xyplex 811- Loopback not allowed with active virtual calls
You cannot enable Loopback mode with active virtual calls.
814 - LCN in use by port x.
The logical channel number you assigned to a port while trying to assign a PVC at
that port is currently in use by port x. Each port that supports a PVC must have a
unique logical channel number.
815 - LCN is out of range.
The logical channel number you assigned to a port while trying to configure a PVC
at that port is out of the range of valid logical channel numbers.
816 - Port x is a PVC
You attempted to assign a permanent switched virtual circuit to port x, which has
already been configured as a permanent virtual circuit. A port can be assigned
either a PVC or a PSVC; not both.
817 - Port x is a permanent SVC
You attempted to assign a permanent virtual circuit to port x, which has already
been assigned to a permanent switched virtual circuit. A port can be assigned
either a PVC or a PSVC; not both.
End of Appendix
0010
137
Appendix B
ASCII Values for International Alphabet Number 5
Table B-1. Decimal and Hexadecimal Values for ASCII Characters
(International Alphabet Number 5 - IA5).
Low Nibble
High Nibble
0
1
2
3
4
5
6
7
0
NUL
0
DLE
16
SP
32
0
48
@
64
P
80
`
96
p
112
1
SOH
1
DC1
17
!
33
1
49
A
65
Q
81
a
97
q
113
2
STX
2
DC2
18
"
34
2
50
B
66
R
82
b
98
r
114
3
ETX
3
DC3
19
#
35
3
51
C
67
S
83
c
99
s
115
4
EOT
4
DC4
20
$
36
4
52
D
68
T
84
d
100
t
116
5
ENQ
5
NAK
21
%
37
5
53
E
69
U
85
e
101
u
117
6
ACK
6
SYN
22
&
38
6
54
F
70
V
86
f
102
v
118
7
BEL
7
ETB
23
'
39
7
55
G
71
W
87
g
103
w
119
8
BS
8
CAN
24
(
40
8
56
H
72
X
88
h
104
x
120
9
HT
9
EM
25
)
41
9
57
I
73
Y
89
i
105
y
121
A
LF
10
SUB
26
*
42
:
58
I
74
Z
90
j
106
z
122
B
VT
ESC
27
+
43
;
59
K
75
[
91
k
107
{
123
C
FF
12
FS
28
,
44
<
60
L
76
\
92
l
108
|
124
D
CR
13
GS
29
-
45
=
61
M
77
]
93
m
109
}
125
E
SO
14
RS
30
.
46
>
62
N
78
^
94
n
110
~
126
F
SI
US
31
/
47
?
63
O
79
_
95
o
111
DEL
11
15
127
In Table B-1, the decimal value for each ASCII character appears next to the
character within each cell of the table. For example, the decimal value of the
LineFeed character in column 0, row A, is 10.
End of Appendix
0010
138
Appendix C
PAD Profile Tables
This Appendix includes two blank PAD profile tables, similar to Table 4-2, but without
profile names and parameter values. Use these tables to record the new profile names
and parameter values that you create when you modify the existing profiles that come
predefined with the X.25 Gateway. You can to copy this table before you fill it in, so that
you will have extra blank copies.
0010
139
Profile Tables
Parameters
Profiles
1 PAD Recall
2 Echo
3 Data Forwarding
4 Idle Timer
5 Ancillary Device
Code
6 Control of PAD
Service Signals
7 PAD Operation
/Receipt of Break
8 PAD Discard
9 Padding After
<CR>
10 Line Folding
11 Binary Speed
12 PAD Flow Control
13 Linefeed Insert
after <CR>
14 Linefeed Padding
15 PAD Editing
16 Character Delete
17 Line Delete
18 Line Display
19 Editing PAD
Service Signals
20 Echo Mask
21 Parity Treatment
140
0010
Profile Tables
Parameters
Profiles
1 PAD Recall
2 Echo
3 Data Forwarding
4 Idle Timer
5 Ancillary Device
Code
6 Control of PAD
Service Signals
7 PAD Operation
/Receipt of Break
8 PAD Discard
9 Padding After
<CR>
10 Line Folding
11 Binary Speed
12 PAD Flow Control
13 Linefeed Insert
After <CR>
14 Linefeed Padding
15 PAD Editing
16 Character Delete
17 Line Delete
18 Line Display
19 Editing PAD
Service Signals
20 Echo Mask
21 Parity Treatment
0010
141
Appendix D
Communications Server V5.1 Features not Supported
in X.25 Gateway V1.3
Version 1.3 of the Xyplex X.25 Gateway supports most of the features in protocols in
Version 5.1 of the TCP/IP-LAT Communications Server. This Appendix lists those
features and protocols not supported on X.25 Gateway virtual ports or port 1, and those
features and protocols supported on port 1 only.
Simultaneous Local and Remote Parameter Storage
Simultaneous local and remote parameter storage is supported on the MAXserver 6025
and 6800 standalone X.25 Gateways only; not the 6625 card.
Features and Protocols Not Supported on Virtual Ports or Port 1
0010
•
The APGEN Utility
•
The XPRINTER protocol
•
Event Logging
•
PRT3270
•
The XREMOTE protocol
•
The LPD daemon
143
Unsupported Communications Server Features
Features and Protocols Supported on Port 1 Only
•
Dialback support for modems
Dialup Support for ports
•
Script Serving
•
Autobaud Support for ports
•
Access control for ports
•
Character Size
•
DSRWAIT
•
DSRLOGOUT
•
DCD Timeout
•
Modem Control
•
The Multisessions protocol
•
Remote Modification
End of Appendix
144
0010
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement