Nortel Networks 8000 - Manual (Page 223)

7 LAPB and X.25 configuration
Nortel Secure Router 8000 Series
Configuration -WAN Access
To set up a SVC with a call, you need an X.25 address which adopts the address format
specified in ITU-T Recommendation X.121.
An X.121 address is a string of Arabic numerals ranging from 0 to 15. The following
describes the configuration of some attributes relevant to the X.121 address of an
interface.
- Configuring an alias of an interface
When you forward an X.25 call across the network, different networks are likely to
make certain modifications on the called address according to their own needs, such
as adding or deleting the prefix. In such cases, the destination address of a call that
reaches the X.25 interface may be inconsistent with the X.121 address of the
destination interface; however, the interface accepts this call. At this time, one or
multiple aliases should be specified for this interface.
To satisfy the requirements of different networks, nine matching modes and the
formats of corresponding alias strings are defined for X.25 in the SR8000, as shown
in the following table.
Matching
mode Meaning Example
Free Free matching, the alias string
is in the form of "1234". 1234 will match with 561234, 1234567
and 956123478, but will not match
with 12354.
free-ext Extended free matching, the
alias string is in the form of
"_1234_".
"^1234_" will match with
678123459, but will not match with
68123459, 67812345, and
6781234591.
Left Left-justified matching mode,
the alias string is in the form of
"$1234".
$1234 will match with 1234567 and
12346790, but will not match with
3123478 and 123784.
left-ext Extended left-justified
matching mode, the alias string
is in the form of "$1234_".
$1234_ will match with 1234679 and
1234872, but will not match with
123468 and 12346890.
Right Right-justified match mode,
the alias string is in the form of
"1234$".
1234$ will match with 791234 and
6901234, but will not match with
7912345 and 6212534.
right-ext Extended right-justified
matching mode, the alias string
is in the form of "^.1234$".
_.1234$ will match with 79001234
and 86901234, but will not match with
7912345 and 506212534.
Strict Strict matching mode, the alias
string is in the form of
"$1234$".
$1234$ can only match with 1234
Whole Whole matching mode, the
alias string is in the form of
(( ((
........ will match with all the valid
X.121 addresses with the length of 8
whole-ext Extended whole matching
mode, the alias string can only
be *.
* will match with all the valid X.121
addresses
7-20 Nortel Networks Inc. Issue 5.3 (30 March 2009)