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Subscriber addressing, Subscriber addressing -22, Wildcard addressing example -22 – Cabletron Systems 1800 User Manual

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Configuring X.25

8-21

Subscriber Addressing

Subcriber IDs are the called and calling addresses that are placed in call packets. Each
Subscriber ID record also defines routing for calls to the subscriber. Each subscriber
ID, or address, consists of up to 15 digits, including (if desired) question marks and/
or asterisks used as wildcards. (See "Wildcards in Subscriber Addresses.")

Subscribers using a public data network (PDN) must conform to the format used by
the PDN. For example, CCITT Recommendation X.121 specifies this format: a one-
digit international code, followed by a four-digit Data Network Identification Code
(DNIC), followed by up to 10 digits of Network Terminal Number (NTN).

A private network (that will not communicate with other networks) does not need to
follow the format—any or all of the digits can be used as desired, following the guide-
lines in this chapter.

Wildcards in Subscriber Addresses

Each subscriber is assigned to a SmartSwitch 1800 port, and more than one subscriber
device can use a port. To eliminate the need to specify the complete ID of every sub-
scriber on the port, the question mark and the asterisk can be used as “wildcard” char-
acters.

A question mark in an address matches any single digit. For example,

3110??????????

is any 14-digit address that begins with

3110

.

An asterisk matches any combination of digits, including none at all. For example,

3110*00

is any address that starts with

3110

and ends with

00

, including

311000

(but not

31100

—overlapping is not allowed). Note that

*

by itself is very important, because it

matches any address.

Wildcards can be combined. The address

3110??*

is any address beginning with

3110

and containing at least two more digits.

The following figure shows an example of wildcard addressing.

Figure 8-7 Wildcard Addressing Example

Node 1

Node 2

00100

12301

12302

12303

12304

P1

P3 - Subscriber ID

123*

L1,P0

L0,P0
L0,P1
L0,P2
L0,P3