Administrator's Guide

Glossary and abbreviations
555-233-5061980 Issue 5 October 2002
loop-start trunk
A trunk on which, after establishing a connection with a distant switching system for an outgoing call, the
system waits for a signal on the loop formed by the trunk leads before sending the digits of the called number.
loss plan
The overall plan, used in network design and management, for creating and maintaining consistent signal
strength across the network. The term also applies to local management of signal strength to achieve appro-
priate levels for specific applications.
LSP
Local Survivable Processor
LSU
Local storage unit
LWC
Leave Word Calling
M
MAC
Medium access
MADU
Modular asynchronous data unit
main distribution frame (MDF)
A device that mounts to the wall inside the system equipment room. The MDF provides a connection point
from outside telephone lines to the PBX switch and to the inside telephone stations.
main-satellite-tributary
A private network configuration that can either stand alone or access an ETN. A main switch provides inter-
connection, via tie trunks, with one or more subtending switches, called satellites; all attendant positions for
the main/satellite configuration; and access to and from the public network. To a user outside the complex, a
main/satellite configuration appears as one switch, with one listed directory number (LDN). A tributary
switch is connected to the main switch via tie trunks, but has its own attendant positions and LDN.
maintenance
Activities involved in keeping a telecommunications system in proper working condition: the detection and
isolation of software and hardware faults, and automatic and manual recovery from these faults.
management terminal
The terminal that is used by the system administrator to administer the switch. The terminal may also be used
to access the BCMS feature.
major alarm
An indication of a failure that has caused critical degradation of service and requires immediate attention.
Major alarms are automatically displayed on LEDs on the attendant console and maintenance or alarming cir-
cuit pack, logged to the alarm log, and reported to a remote maintenance facility, if applicable.
Manual-In work mode
One of four agent work modes: the mode in which an agent is ready to process another call manually. See
Auto-In Work mode for a contrast.
MAP
Maintenance action process