Cabletron Systems CSMIM-T1, Administrator'S Manual

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CSMIM/Micro-CS Management Application Guide 8-1
CHAPTER 8
SETTING ISDN PRIMARY RATE
ANNEX VALUES
Annex Manager allows you to configure ISDN Primary Rate Annexes in its
Setup and Customize modes. The Setup mode allows you to change values
for the most commonly-used parameters. The Customize mode provides
access to all parameters and to the Annex configuration file.
ISDN Primary Rate Annexes use circuit-switched B channels for voice
(modem) and data calls and packet-switched D channels for call setup,
teardown, and connection management over dedicated trunk lines.
❑
In the United States, Canada, and Japan, PRI service uses T1
trunk lines. A single T1 line supports 23 B channels and one
D channel.
❑
In Europe and the Pacific Rim, PRI service uses E1 trunk lines.
A single E1 line supports 30 B channels and 2 D channels.
The PRI line interface and the Ethernet port are the only physical ports on
the ISDN Primary Rate Annex. When a user dials in to an ISDN Primary
Rate Annex, calls are assigned dynamically to an available B channel. The
Annex accepts:
❑
Voice (modem) calls by negotiating for available B channels
and modems and by checking configuration parameter
settings.
❑
V.120 calls by using a terminal adapter (TA) to convert analog
data into V.120 frames. After negotiating for B channels,
resources, and configuration parameters, the Annex converts
the V.120 frames into asynchronous data streams.
❑
Synchronous PPP calls from PCs with adapter cards that
support PPP encapsulation over ISDN. Like modem and V.120
calls, these calls require negotiation for B channels, resources,
and configuration parameters.
The ISDN Primary Rate Annex can assign a call to any available B channel.
It uses: