![](/images/new-backgrounds/1309163/309163735x1.webp)
4.3 List of Abbreviations
T
TAFAS Trunk Answer from Any Station TEI
Terminal Endpoint Identifier TRG
Trunk Group
TRS/Barring Toll Restriction/Call Barring
U
UCD Uniform Call Distribution
V
VM Voice Mail
VoIP Voice over Internet Protocol VPN
Virtual Private Network VPS
Voice Processing System
X
XDP eXtra Device Port