Dialogic Brooktrout Digital Board Installation And Configuration Manual page 200

Time slot
Unit number
VAD
Work channel
March 2013
A logical entity that corresponds to one telephone call.
1. In telephony configuration files and functions, a unit is a
hardware port on a Dialogic® Brooktrout® board and is numbered
starting at 0 (to denote a TDM bus); from 1 to n (for a specific T1/E1
interface).
2. In some Bfv functions (for example, BfvLineAttach), an ordinal
channel number. Its range is 0...n-1, where n is the number of
channels in a system.
Voice Activity Detection
One of the channels on a module that is available for
non-administrative purposes as a result of downloading firmware. A
module configured for 48 channels when firmware download is
performed has 48 work channels and one administrative channel.
Logical work channel numbers start at 2 on each module.
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