AT&T MERLIN LEGEND Communications System Release 2.0 Maintenance And Troubleshooting Manual page 210

Glossary
IROB (in-range out-of-building) protector
A surge protection device for off-premises telephones at a location within
1000 ft (305 m) of cable distance from the communications system control
unit.
Key mode
A mode of operation in which the communications system uses direct facility
terminations (DFTs) on line buttons with a separate path for internal calling.
LAN
local area network
LDN
listed directory number
line coding
The pattern data assumes as it is transmitted over a communications channel,
line compensation
An adjustment for the amount of cable loss in decibels (dBs), based on the
length of cable between a DS1 module and a channel service unit (CSU) or
other far-end connection point.
local host computer access
A method for connecting a telephone jack to an on-site computer for data-
only calls through a modem or data module.
logical ID
A numbering sequence used to identify station and trunk locations on the
communications system control unit.
loop-start (LS) trunk
A trunk on which a closure between the tip and ring leads is used to originate
or answer a call. High-voltage 20-Hz AC ringing from the central office (CO)
signals an incoming call.
Magic on Hold®
A customized Music-on-Hold (MOH) system that promotes the customer's
products and services.
GL-8 Glossary