AQM

Audio Quality Measurement

eHRPD

Enhanced High Rate Packet Data

EPS

Evolved Packet System

HSS

Home Subscriber Server

I-CSCF

Interrogating Call Session Control Function

IMS

IP Multimedia Subsystem

KPI

Key Performance Indicator

MO

Mobile Originated

MOS

Mean Opinion Score

MT

Mobile Terminated

MTAS

Multimedia Telephony Application Server

NAS

Non-Access Stratum

P-CSCF

Proxy Call Session Control Function

PESQ

Perceptual Evaluation of Speech Quality

POLQA

Perceptual Objective Listening Quality Assessment

PRACK

Provisional ACK

RRC

Radio Resource Control

RRC

Radio Resource Control

RTP

Real-Time Transport Protocol

S-CSCF

Serving Call Session Control Function

SIP

Session Initiation Protocol

SIP

Session Initiation Protocol

ViLTE

Video over LTE

VoLTE

Voice over LTE