AT&T MERLIN LEGEND Release 3.1, Руководство по системному программированию

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Glossary
GL–16
System Programming
Key mode One of three modes of system operation, in which the
system uses personal lines on line buttons for outside calls,
with a separate interface (
ICOM buttons ) for internal
calling. See also
Behind Switch mode
and
Hybrid/PBX
mode.
L
LAN (local area network) Arrangement of interconnected
personal computers or terminals, sometimes accessing a
host computer, sometimes sharing resources like files and
printers.
LDN listed directory number
LED (light-emitting diode) Semiconductor device that produces
light when voltage is applied; light on a telephone.
line Connection between extensions within the communications
system; often, however, used synonymously with
trunk
.
line and trunk
assignment Assignment of lines and trunks connected to the system
control unit to specific buttons on each telephone.
line coding Pattern that data assumes as it is transmitted over a
communications channel.
line compensation Adjustment for the amount of cable loss in decibels (dB),
based on the length of cable between a 100D module and
a channel service unit (
CSU
) or other far-end connection
point.
line/trunk Refers to inside system lines and outside trunks in general
terms. See also
line
and
trunk
.
line/trunk jack Physical interface on a module in the control unit for
connecting an outside trunk to the communications
system. Also called “trunk jack.”
line/trunk and
extension module Module on which the jacks for connecting central office
lines/trunks and/or the jacks for connecting the extensions
are located.
local host computer
access A method for connecting an extension jack to an on-site
computer for data-only calls through a
modem
or data
module.
local loop See
access line.