3 Definitions, symbols and abbreviations

23.2313GPPRelease 17SIP-I based circuit-switched core networkStage 2TS

3.1 Definitions

For the purposes of the present document, the terms and definitions given in TR 21.905 [1] and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905 [1].

3.2 Symbols

For the purposes of the present document, the following symbols apply:

Iu Interface between the RNS and the core network. It is also considered as a reference point.

Mc Interface between the server and the media gateway.

Nb Interface between media gateways.

Nc The NNI call control interface between (G)MSC servers.

3.3 Abbreviations

For the purposes of the present document, the abbreviations given in TR 21.905 [1] and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905 [1].

BCF Bearer Control Function

BICC Bearer Independent Call Control

BICN Bearer Independent Core Network

CS Circuit Switched

DSP Digital Signal Processing

GERAN GSM/EDGE Radio Access Network

(G)MSC-S (Gateway) MSC Server

IAM Initial Address Message

IETF Internet Engineering Task Force

IP Internet Protocol

IPBCP IP Bearer Control Protocol

IWF Interworking Function

LCLS Local Call Local Switch

MGCF Media Gateway Control Function

MGW Media Gateway

MSC-S MSC Server

MSC/IWF IWF at call control layer toward external network (see 3GPP TS 29.007 [6])

NNI Network-Network interface

OoBTC Out of Band Transcoder Control

PRACK Provisional Response Acknowledgement

RTO Remote Transcoder Operation

RTP Real-Time Transport Protocol

SCTP Stream Control Transmission Protocol

SCUDIF Service Change and UDI Fallback

SIP Session Initiation Protocol

SDP Session Description Protocol

TCP Transmission Control Protocol

TDM Time-Division Multiplexing

TFO Tandem Free Operation

TrFO Transcoder Free Operation

UDP User Datagram Protocol

UTRAN UMTS Terrestrial Radio Access Network