AT&T MERLIN LEGEND Release 2.0 Equipment And Operations Manual page 276

Glossary
PBX
PC
PCM
personal line
pool
port
power supply
module
PRI
Primary Rate
Interface
prime line
processor
module
protocol
public network
QCC
GL-14
Glossary
Private branch exchange
Personal computer
Pulse code modulation.
A central office line that rings only at the user's telephone.
On a Hybrid/PBX system, a grouping of outside trunks that
users can choose with multiple pool buttons or by dialing
access codes on a System Access button on the telephone.
Pools are also used by the Automatic Route Selection (ARS)
feature to choose the least expensive method to route a
call.
A point of access into a communications system, computer,
network, or other electronic device.
A device that directs electricity to modules and telephones
on the communications system. One power supply module
is needed for each carrier, and an auxiliary power unit is
added if the module exceeds capacity.
(Primary Rate Interface) A standard interface that specifies
the protocol used between two or more communications
systems. PRI runs at 1.544 Mbps and, as used in North
America, provides twenty–three 64-kbps B-channels (voice
or data) and one 64–kbps D-channel (signaling). The D-
channel is the 24th channel of the interface and contains
multiplexed signaling information for the other 23 channels.
See PRI
An individual extension number assigned to a telephone in
a Behind Switch System. Each telephone user has a prime
line and is automatically connected to that line upon lifting
the handset.
The module in the second slot of the basic carrier that
contains the software that runs the communications system.
A set of conventions governing the format and timing of
message exchanges between devices, such as an analog
multiline telephone and the communications system control
unit.
A network that is commonly accessible for local or long-
distance calling. Also called public switched telephone
network (PSTN).
(Queued Call Console) An answering position available to
MLX-20L telephone users only in the Hybrid/PBX mode.
The QCC is used by system operators to answer and direct
(transfer) calls, serve as a message center, and monitor
system operation. Calls are sent to a common QCC queue