APN

Access Point Name

ACD

Automatic Call Distribution

CC

Country Code

CLIP

Calling Line Identification Presentation

CLIR

Calling Line Identification Restriction

CS

Circuit Switched

DSCP

Differentiated Services Code Point

ECACS

Emergency Call Address Change Service

FMC

Fixed-Mobile Convergence

HTTP

Hypertext Transfer Protocol

HTTPS

Hypertext Transfer Protocol Secure Sockets

IM&P

Instant Messaging and Presence

IMRN

IP Multimedia Routing Number

IP

Internet Protocol

NAT

Network Address Translation

PBX

Private Branch Exchange

PIN

Personal Identification Number

QoS

Quality of Service

RCS

Rich Communication Suite

RTCP

Real-Time Control Protocol

SBC

Session Border Controller

SIM

Subscriber Identity Module

SIP

Session Initiation Protocol

TN

Telephone Number

ToS

Type of Service

UC

Unified Communications

UI

User Interface

URI

Uniform Resource Identifier

URL

Uniform Resource Locator

VM

Voice Mail

VoIP

Voice Over IP

VPN

Virtual Private Network

XMPP

Extensible Messaging and Presence Protocol

XR

Extended Report

Xsi

Xtended Services Interface