AT&T 2500 series Network Router User Manual


 
COMMUNICATION SYSTEM NETWORKING — AN OVERVIEW 2-9
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LOCAL
STATION
OR
NETWORK
OR
NETWORK
OR
NETWORK
EXTENSION NO. PORTABILITY
EXTENSION NO. STEERING
TO AAR
TO AAR
TO TRUNK
TO ARS
TO AAR
RNX + EXT
NODE + EXT
9 + (NPA) + NNX + XXXX
DAC + EXT
EXT
8 + RNX + EXT
INTERNAL
DIAL
PLAN
DAC + EXT
UNIFORM DIAL PLAN FUNCTION
OR
NETWORK
Figure 2-1. Internal Dial Plan Interactions
— Local station number dialing— When only an extension number is dialed, the internal dial plan first
attempts to match the extension number with a terminal on the same switch. If no match is made
and if MS/T or ETN networking software is active, the internal dial plan submits the call to the
networking software for further analysis. When no networking software is active, however, the
internal dial plan sends the call to intercept.
— Extension number steering — On a DIMENSION, System 85, or Generic 2 communications system, if
the Multipremises package is activated, the dial plan uses the extension number it receives to find a
dial access code. The system sends the call over the trunk group that the access code designates.
— Extension number portability — If extension number portability has been administered on the
switch, the internal plan uses the extension number it receives to find the node number of the
destination switch. It sends both the extension and node number to AAR for processing.
Extension number portability is an option that can be administered when the ETN (Standard
Network) package has been activated on a System 85 (R2V3 and R2V4) or Generic 2
communications system.
— The Uniform Dial Plan (UDP) function — If the UDP function is available, the internal dial plan
uses the extension number it receives to find the RNX of the destination switch. (The System 75
and Generic 1 use the PBX code embedded in the extension number to find the RNX.) It sends both