Glossary and Abbreviations
555-230-024GL-4 Issue 5 January 1998
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
ANAnalog
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 control-channel message set (CCMS) to manage comm un ica tio ns betw e en 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 variety 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.
AOL
Attendant-offered load
AP Applications processor
APLT
Advanced Private-Line Termination