Administrator's Guide

Glossary and abbreviations
555-233-5061952 Issue 5 October 2002
ALBO
Automatic Line Build Out
All trunks busy (ATB)
The state in which no trunks are available for call handling.
ALM-ACK
Alarm acknowledge
American Standard Code for Information Interchange
See ASCII (American Standard Code for Information Interchange).
AMW
Automatic Message Waiting
AN
Analog
analog
The representation of information by continuously variable physical quantities such as amplitude, frequency,
and phase. See also digital.
analog data
Data that is transmitted over a digital facility in analog (PCM) form. The data must pass through a modem
either at both ends or at a modem pool at the distant end.
analog telephone
A telephone that receives acoustic voice signals and sends analog electrical signals along the telephone line.
Analog telephones are usually served by a single wire pair (tip and ring). The model-2500 telephone set is a
typical example of an analog telephone.
analog-to-digital converter (ADC)
A device that converts an analog signal to digital form. See also digital-to-analog converter (DAC).
angel
A microprocessor located on each port card in a processor port network (PPN). The angel uses the con-
trol-channel message set (CCMS) to manage communications between the port card and the archangel on the
controlling switch-processing element (SPE). The angel also monitors the status of other microprocessors on
a port card and maintains error counters and thresholds.
ANI
See Automatic Number Identification (ANI).
ANSI
American National Standards Institute. A United States professional/technical association supporting a vari-
ety of standards.
answerback code
A number used to respond to a page from a code-calling or loudspeaker-paging system, or to retrieve a parked
call.
AOC
Advice of Charge
AOL
Attendant-offered load
AP
Applications processor