Chapter 12: AI2524 X.25 Configuration Steps

Configure

Additional X.25

Datagram

Transport

Features

The Cisco IOS software allows you to configure additional X.25 dat- agram transport features, including various user facilities defined for X.25 call setup.

This section describes the X.25 datagram transport features you can configure by using the options in the x25 map or x25 pvc en- capsulation command (or by setting an interface default). Th tasks you perform depend upon your needs, the structure of your net- work, and the requirements of the service provider.

To configure the optional parameters, user facilities, and special fea- tures, perform one or more of these tasks:

zConfigure X.25 Payload Compression

zConfigure the Encapsulation Virtual Circuit Idle Time

zIncrease the Number of Virtual Circuits Allowed

zConfigure the Ignore Destination Time

zEstablish the Packet Acknowledgment Policy

zConfigure X.25 User Facilities

zDefine the Virtual Circuit Packet Hold Queue Size

zRestrict Map Usage

Configure X.25 Payload Compression

For increased efficiency on relatively slow networks, the Cisco IOS software supports X.25 payload compression of outgoing encapsula- tion traffic.

Several restrictions apply to X.25 payload compression:

zThe compressed virtual circuit must connect two Cisco routers, because X.25 payload compression is not standardized.

The data packets conform to the X.25 protocol rules, so a com- pressed virtual circuit can be switched through standard X.25 equipment. However, only Cisco routers can compress and de- compress the data.

zOnly datagram traffic can be compressed, although all the encap- sulation methods supported by Cisco routers are available. For ex- ample, an IETF multiprotocol virtual circuit can be compressed.

SVCs cannot be translated between compressed and uncom pressed data, nor can PAD data be compressed.

August 1997

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AIS AI2524 user manual Configure Additional Datagram Transport Features, Configure X.25 Payload Compression