Nortel Communication Server 1000 Manual page 20

20 Overview
carrying data/voice information — call processing signaling information is
not carried over a B-channel. Voice and data transmission over DASS2
links is done at a rate of 64 Kbit/s. There may be up to 30 B-channels per
D-channel.
The Data Channel (D-channel) carries call processing information
between PBXs for the associated B-channels (call set-up and tear-down
information, network feature activation information). The format is a High
Level Data Link Control frame. For DASS2 applications, the D-channel
must be a 64 Kbit/s digital channel. It may exist on the same or different
carrying medium as the B-channels that it supports. One D-channel may
support up to 30 B-channels.
Refer to
depiction of how channels are typically configured for a DASS2 system.
Figure 4
Channel configurations for DASS2
Figure 4 "Channel configurations for DASS2" (page 20)
Nortel Communication Server 1000
DASS2 Fundamentals
NN43001-571 04.01 4 June 2010
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