Terminal Services Configuration Guide, Cisco IOS Release 15M&T
End-of-Record Function for DCNs
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End-of-Record Function for DCNs

Table Of Contents

End-of-Record Function for DCNs

Contents

Prerequisites for End-of-Record Function for DCNs

Restrictions for End-of-Record Function for DCNs

Information About End-of-Record Function for DCNs

Data Types

The EOR Marker

Benefits of End-of-Record Function for DCNs

How to Configure End-of-Record Function for DCNs

Configuring the End-of-Record Function for a TCP-to-X.25 Protocol Translation Session

Configuring the End-of-Record Function for an X.25-to-TCP Protocol Translation Session

Troubleshooting Tips

Monitoring and Maintaining the End-of-Record Function for DCNs

Configuration Examples for End-of-Record Function for DCNs

Configuring the End-of-Record Function for DCNs for a TCP-to-X.25 Protocol Translation Session Example

Configuring the End-of-Record Function for DCNs for an X.25-to-TCP Protocol Translation Session Example

Additional References

Related Documents

Standards

MIBs

RFCs

Technical Assistance

Command Reference


End-of-Record Function for DCNs


The Cisco Protocol Translator is designed to support Telnet-like applications that are stream-based, with no recognition or accommodation for logical records. For record-oriented applications, problems can occur because the record boundaries in X.25 data are lost when translation to TCP occurs. The End-of-Record Function for Data Communications Networks (DCNs) feature provides for the configuration of an End of Record (EOR) marker which allows the X.25 logical boundaries to be marked when translated to TCP. The benefit of this feature is that it allows the preservation of logical boundaries when translating X.25 data to TCP, enabling X.25-based networking solutions to adapt to and benefit from TCP/IP technologies.

Feature History for the End-of-Record Function for DCNs

Release
Modification

12.3(2)T

This feature was introduced.


Feature

Finding Support Information for Platforms and Cisco IOS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.

Contents

Prerequisites for End-of-Record Function for DCNs

Restrictions for End-of-Record Function for DCNs

Information About End-of-Record Function for DCNs

How to Configure End-of-Record Function for DCNs

Configuration Examples for End-of-Record Function for DCNs

Additional References

Command Reference

Prerequisites for End-of-Record Function for DCNs

X.25 must be configured. For more information on configuring X.25, see the "Configuring X.25 and LAPB" chapter in the Cisco IOS Wide-Area Networking Configuration Guide.

Restrictions for End-of-Record Function for DCNs

This feature is supported only for X25-to-TCP and TCP-to-X.25 protocol translation sessions.

This feature is not supported for any other types of protocol translation sessions.

Information About End-of-Record Function for DCNs

To configure the End-of-Record Function for DCNs feature, you must understand the following concepts:

Data Types

The EOR Marker

Benefits of End-of-Record Function for DCNs

Data Types

X.25 data

X.25 data is inherently record-oriented. The X.25 protocol defines a bit in the packet called the More-bit (M-bit), which indicates whether the packet should be considered to terminate a logical record.

TCP data

TCP data is inherently stream-oriented. The TCP protocol attaches no significance to TCP segment stream boundaries, and the boundaries may change if the data is re-sent.

The EOR Marker

Logical record boundaries indicated by the combination of the X.25 packet boundaries and the M-bit are not preserved when translation to TCP occurs. The End-of-Record Function for DCNs feature allows the X.25 logical record boundaries to be marked by inserting a configurable string into the TCP stream at each X.25 record boundary. Translation of X.25 packets without the M-bit will invoke the insertion of the EOR marker.

Benefits of End-of-Record Function for DCNs

The benefit of the End-of-Record Function for DCNs feature is that it allows the preservation of logical boundaries when translating X.25 data to TCP, enabling X.25-based networking solutions to adapt to and benefit from TCP/IP technologies.

How to Configure End-of-Record Function for DCNs

This section contains the following procedures:

Configuring the End-of-Record Function for a TCP-to-X.25 Protocol Translation Session

Configuring the End-of-Record Function for an X.25-to-TCP Protocol Translation Session

Monitoring and Maintaining the End-of-Record Function for DCNs

Configuring the End-of-Record Function for a TCP-to-X.25 Protocol Translation Session

Perform this task to enable the End-of-Record Function for DCNs feature for a TCP-to-X.25 protocol translation session.

SUMMARY STEPS

1. enable

2. configure terminal

3. translate tcp incoming-address [incoming-options] x25 outgoing-address [outgoing-options] [global-options] eor marker [insert]

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

translate tcp incoming-address [incoming-options] x25 outgoing-address [outgoing-options] [global-options] eor marker [insert]

Example:

Router(config)# translate tcp 10.60.155.63 x25 12345678 pvc 3 dynamic eor 0x19 insert

Translates an incoming TCP connection request to an X.25 destination address or host name and enables EOR functionality.

eor marker—Defines the EOR marker for the translation session. The marker argument may be any set characters from 1 to 4 in length. Nonprintable characters must be entered in hexadecimal format. Printable characters may be typed in.

insert—Allows the EOR marker to be inserted into the TCP stream after each received X.25 packet that does not contain the M-bit set.

Configuring the End-of-Record Function for an X.25-to-TCP Protocol Translation Session

Perform this task to enable the End-of-Record Function for DCNs feature for an X.25-to-TCP protocol translation session.

SUMMARY STEPS

1. enable

2. configure terminal

3. translate x25 incoming-address [incoming-options [pvc number [pvc-options]]] tcp outgoing-address [outgoing-options] [global-options] eor marker [insert]

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

configure terminal

Example:

Router# configure terminal

Enters global configuration mode.

Step 3 

translate x25 incoming-address [incoming-options [pvc number [pvc-options]]] tcp outgoing-address [outgoing-options] [global-options] eor marker [insert]

Example:

Router(config)# translate x25 12345678 pvc 3 tcp 10.60.155.63 eor AAA insert

Translates an incoming X.25 connection request to a TCP destination address or host name and enables EOR functionality.

eor marker—Defines the EOR marker for the translation session. The marker argument may be any set of characters from 1 to 4 in length. Nonprintable characters must be entered in hexadecimal format. Printable characters may be typed in.

insert—Allows the EOR marker to be inserted into the TCP stream after each received X.25 packet that does not contain the M-bit set.

Troubleshooting Tips

In the event that the End-of-Record Function for DCNs feature is not operating correctly, use the following debug commands in privileged EXEC mode to determine the source of the problem:

debug translate

debug x25 all

debug pad

Refer to the Cisco IOS Debug Command Reference publication for information about the debug translate, debug x25 all, and debug pad commands.

Monitoring and Maintaining the End-of-Record Function for DCNs

This task results in the display of information about any protocol translation information configured with the translate command.

SUMMARY STEPS

1. enable

2. show translate

DETAILED STEPS

 
Command or Action
Purpose

Step 1 

enable

Example:

Router> enable

Enables privileged EXEC mode.

Enter your password if prompted.

Step 2 

show translate

Example:

Router# show translate

Displays information about translation sessions that have been configured.

Configuration Examples for End-of-Record Function for DCNs

This section contains the following configuration example:

Configuring the End-of-Record Function for DCNs for a TCP-to-X.25 Protocol Translation Session Example

Configuring the End-of-Record Function for DCNs for an X.25-to-TCP Protocol Translation Session Example

Configuring the End-of-Record Function for DCNs for a TCP-to-X.25 Protocol Translation Session Example

The following example configures a TCP-to-X.25 protocol translation session to insert an EOR marker in a TCP packet after each received X.25 packet that does not contain the M-bit set. The EOR marker in this example consists of nonprintable characters and is entered in hexadecimal format.

translate tcp 10.60.155.63 x25 12345678 pvc 3 dynamic eor 0x19 insert

Configuring the End-of-Record Function for DCNs for an X.25-to-TCP Protocol Translation Session Example

The following example configures an X.25-to-TCP protocol translation session to insert an EOR marker in a TCP packet after each received X.25 packet that does not contain the M-bit set. The EOR marker in this example consists of printable characters.

translate x25 12345678 pvc 3 tcp 10.60.155.63 eor AAA insert

Additional References

The following sections provide additional information related to the End-of-Record Function for DCNs feature.

Related Documents

Related Topic
Document Title

Additional information about configuring protocol translation

"Configuring Protocol Translation and Virtual Asynchronous Devices

Additional protocol translation commands: complete command syntax, command mode, defaults, usage guidelines and examples

Cisco IOS Terminal Services Command Reference

Information on configuring X.25

Cisco IOS Wide-Area Networking Configuration Guide.

Additional X.25 commands

Cisco IOS Wide-Area Networking Command Reference


Standards

Standards
Title

None


MIBs

MIBs
MIBs Link

None

To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs


RFCs

RFCs
Title

None


Technical Assistance

Description
Link

Technical Assistance Center (TAC) home page, containing 30,000 pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.

http://www.cisco.com/public/support/tac/home.shtml


Command Reference

The following commands are introduced or modified in the feature or features documented in this module. For information about these commands, see the Cisco IOS Terminal Services Command Reference at http://www.cisco.com/en/US/docs/ios/termserv/command/reference/tsv_book.html. For information about all Cisco IOS commands, go to the Command Lookup Tool at http://tools.cisco.com/Support/CLILookup or to the Cisco IOS Master Commands List.

show translate

translate tcp

translate x25