Glossary – AT&T DEFINITY 7200 series User Manual
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GLOSSARY
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24th-channel signaling
Digital signal level-1 (DS1) signaling in which the signaling for each of
the first 23 channels is multiplexed onto the 24th channel, thereby
providing a full 64 kbps for user data on each of the first 23 channels.
Also called clear-channel signaling. See also common-channel signaling
and primary rate interface.
800 Service
A service that allows incoming calls to be made from certain geographical
areas to an assigned number for a flat-rate charge based on expected usage.
Also called
MEGACOM
800 service. See also
access code
A 1-, 2-, 3-, or 4-digit dial code used to activate or cancel a feature or
access an outgoing trunk. Star (*) or pound (#) can be used as the first
digit of an access code.
access tie trunk
A trunk that connects a main switch with a tandem switch in an electronic
tandem network (ETN). An access tie trunk can also be used to connect a
system or tandem to a serving office or service node. Also called access
trunk.
ACD
See Automatic Call Distribution.
ACU
adaptive differential
pulse-code modulation
A 32-kbps encoding algorithm that allows up to 48 voice band channels to
be carried on one DS1 facility.
ADM
administer
To access, establish, or change parameters associated with the services and
features of a system.
ADU
alternate facilities
restriction level (AFRL)
An assigned alternate number that reflects allowed access levels and
determines both the kinds of calls that can be made and the kinds of
facilities that can be used when accessing trunks via Automatic Alternate
Routing (AAR). See also facilities restriction level.
alternate voice/data
(AVD)
A digital signal level-1 (DS1) trunk-facility translation that defines the use
of that facility for either voice or data-protocol modes.
GL-1