Nortel TFC002 Manual page 13

Barge-In and Busy Verify
CAS attendants are able to "barge-in" on trunks located at the Main location
and busy-verify telephones at the Main location, but are not able to perform
these functions for Remote locations. The local console at each Remote
location can barge-in or busy-verify its local trunks and telephones. Neither
the CAS attendant nor the local attendant can barge-in on an idle or busy
Release Link Trunk (RLT).
Basic or Network Alternate Route Selection
Where least-cost routing to all special services and toll routes is desired, the
Basic or Network Alternate Route Selection (BARS/NARS) feature can be
provided at the Main CAS location and accessed through TIE trunks from all
Remote locations. This eliminates potential supervision problems with
tandem TIE trunk connections that occur when BARS/NARS is provided
separately at each location. The centralized BARS/NARS feature can be used
only if all special-service outgoing toll calls are placed through the Main
CAS location.
To ensure adequate Class of Service restrictions for controlling access to
special services and toll routes, the following actions can be taken:
— Supply two separate TIE trunk routes from each Remote location to the
Main location. One should be unrestricted or conditionally toll-denied,
and the other toll-denied.
— Assign Trunk Group Access Restriction (TGAR) codes to control access
from telephones at each Remote location to one or the other of these two
trunks' routes.
Busy Lamp Field Array
The busy-lamp field indicates the status of telephones for the Main
location only.
Call Detail Recording
When a CAS network is equipped with Call Detail Recording (CDR), the
following points should be noted:
— The CDR should be located at the Main site. This also applies to any
special service trunks.
Centralized Attendant Service
Feature description
Description and engineering
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