AT&T MERLIN LEGEND System Reference Manual page 627

Abbreviations Glossary
SMDR Station Message Detail Recording
SPC system programming console
SPM System Programming and Maintenance
SSN Switched Services Network
time-division multiplexing
TDM
terminal equipment identifier
TEI
tip and ring
T/R
TSI
time-slot interchanger
TTR touch-tone receiver
UDM universal data module
UPAM Universal Paging Access Module
UPS
uninterruptible power supply
VA volt-ampere
VAC volts AC
VAN value-added network
voice announcement unit
VAU
V M I voice messaging interface
V.T. voice terminal
w
watts
WATS wide area telecommunications service
ZCS zero code suppression
M-2 Abbreviations Glossary