AT&T MERLIN LEGEND Release 4.0 Feature Reference page 427

Feature Reference
Table 30. Sample PRI Dial Plan Routing Table
Entry
Service
# of digits in
CdPN
Example #
Pattern
Digit deletion
Digit addition
When Routing by Dial Plan is used for an incoming call, if the programmed
service, number of digits in the Called Party Number (CdPN) and patterns
match those associated with the incoming call, the appropriate digit deletion
and addition are performed. The process is as follows:
1. The programmed service is compared with the B-channel service, if
supplied. A match is found if the two services are equivalent or if the
programmed service in the Dial Plan Routing Table is All Services. If a
match is found, the system continues to search the entry. If no match is
found or if No Service is specified, the system skips the entry and
proceeds to the next one. If no service is supplied, the call is matched to
No Service table entries.
2. The programmed number of digits is compared with the number of digits
in the actual Called Party Number. A match is found if the two numbers
are equivalent or if the programmed number of digits is 0. If a match is
found, the system continues to search the entry. If no match is found, the
system skips the entry and proceeds to the next one. If the programmed
number of digits is 0, any number of digits in the Called Party Number is
acceptable.
3. The programmed pattern is compared with the digits associated with the
incoming call. If the pattern matches, the entry is tagged as a possible
best match for the incoming call; it is possible that more than one entry
can match the incoming call. The entry chosen is the one that matches
on the greatest number of digits in the pattern. For example, if 555-2000
is the Called Party Number and the two patterns that match are 555 and
5552, the entry associated with 5552 is chosen as the best match. If the
pattern is not programmed, it is considered a match with the number of
digits in the pattern equal to 0.
4. After the table is scanned and the best match is found, the programmed
digit manipulation (addition and/or deletion) associated with the entry is
performed. If the digit manipulation results in an invalid dial plan
endpoint, the call is routed to the endpoint for unassigned DID calls.
0 1
SDN SDN
7 10
555-1234 908-555-1234
555 [none]
3 6
[none] [none]
2 3 ... 15
MEG800 No Service
10 [not specified]
[none] [none]
10 14
1234 0
Primary Rate Interface (PRI) and T1
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