Brooktrout Technology IRAS-24A w/ T1-RBS, Installation And Reference Manual

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Service Provisioning A-13
What to Order Ordering PRI-ISDN Service
Ordering a PRI-ISDN line is similar to ordering a T1 line;
there are few features or options to consider. When you call
to order service, ask for Primary Rate ISDN (23B+D) service
provisioned as follows.
❐
Extended Superframe (ESF) framing and B8ZS line
coding.
❐
Each B-channel provisioned for circuit-switched data
and voice (CSD/V).
❐
The D-channel on channel 24 of the line (the
IRAS-24A cannot recognize a D-channel on any other
channel).
❐
No packet handlers other than the D-channel. Some
service providers offer special packet data transfer
capabilities (such as X.25 messages) over the
D-channel; these capabilities are not usable with the
IRAS-24A card.
❐
64 kbps clear channel service end-to-end for every
call. Calls that start on ISDN lines may be routed over
older T1 digital lines that use a different form of call
signaling that “robs” bits from the channel. This bit
robbing reduces the available channel bandwidth to
56 kbps. If your service provider cannot guarantee
clear channel service, you may need to turn on rate
adaption. Refer to Chapter 3 in this guide for
information on setting this value.