Configure X.25 205

of a call that reaches X.25 interface may be inconsistent with X.121 address of the destination interface (because the destination address of this call is modified within the network), still the interface will accept this call. At this time, one or multiple aliases should be specified for this interface by performing the following tasks in the interface view:

Table 242 Specify/Cancel an alias for the interface

Task

Command

 

 

Specify an alias for the interface

x25 alias-policy match-type

 

alias-string

 

 

Cancel the specification of an alias for the

undo x25 alias-policy

interface

match-type alias-string

 

 

To satisfy the requirements of different networks, nine matching modes and the formats of corresponding alias strings are defined for X.25 in 3Com Router series, as shown in the following table.

Table 243 Alias match modes and meanings

Matching mode

Meaning

Example

 

 

 

Free

Free matching, the alias string is in

1234 will match with 561234,

 

the form of 1234

1234567 and 956123478, but will

 

 

not match with 12354.

 

 

 

free-ext

Extended free matching, the alias

…1234.. will match with

 

string is in the form of …1234..

678123459, but will not match

 

 

with 68123459, 67812345 and

 

 

6781234591.

 

 

 

Left

Left-justified matching mode, the

$1234 will match with 1234567

 

alias string is in the form of $1234

and 12346790, but will not match

 

 

with 3123478 and 123784.

 

 

 

left-ext

Extended left-justified matching

$1234… will match with 1234679

 

mode, the alias string is in the

and 1234872, but will not match

 

form of $1234…

with 123468 and 12346890.

 

 

 

Right

Right-justified match mode, the

1234$ will match with 791234 and

 

alias string is in the form of 1234$

6901234, but will not match with

 

 

7912345 and 6212534.

 

 

 

right-ext

Extended right-justified matching

….1234$ will match with

 

mode, the alias string is in the

79001234 and 86901234, but will

 

form of ….1234$

not match with 7912345 and

 

 

506212534.

 

 

 

Strict

Strict matching mode, the alias

$1234$ can only match with 1234

 

string is in the form of $1234$

 

 

 

 

Whole

Whole matching mode, the alias

........ will match with all the valid

 

string is in the form of

X.121 addresses with the length of

 

 

8

 

 

 

whole-ext

Extended whole matching mode,

* will match with all the valid X.121

 

the alias string can only be *

addresses

 

 

 

3Configure the attributes related to the address code block in the call packet or call accept packet

As specified in X.25 protocol, the call packet must carry the information set of both the calling DTE address (source address) and the called DTE address (destination address). This address information set is called the address code block. While in call accept packet, some networks require that both (the calling DTE address and the called DTE address) be carried, some networks require that only one of the two be carried, while some others require that neither should be carried. X.25 in 3Com Router series enables users to make choices according to the requirement of specific network. Perform the following task in interface view.

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3Com 10014299 manual Specify/Cancel an alias for the interface, Alias match modes and meanings, Alias-string