3 Definitions, symbols and abbreviations

29.1653GPPInter-IMS Network to Network Interface (NNI)Release 18TS

3.1 Definitions

For the purposes of the present document, the terms and definitions given in 3GPP 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 3GPP TR 21.905 [1].

example: text used to clarify abstract rules by applying them literally.

IM CN subsystem: (IP Multimedia CN subsystem) comprises of all CN elements for the provision of IP multimedia applications over IP multimedia sessions, as specified in 3GPP TS 22.228 [9].

IP multimedia session: as specified in 3GPP TS 22.228 [9] an IP multimedia session is a set of multimedia senders and receivers and the data streams flowing from senders to receivers. IP multimedia sessions are supported by the IP multimedia CN Subsystem and are enabled by IP connectivity bearers (e.g. GPRS as a bearer). A user can invoke concurrent IP multimedia sessions.

non-roaming II-NNI: the II-NNI between IMS home networks, or, if the Roaming Architecture for Voice over IMS with Local Breakout is used, alternatively the II-NNI between the caller’s visited network and the callee’s home network.

roaming II-NNI: the II-NNI between a visited IMS network and the IMS home network; for the Roaming Architecture for Voice over IMS with Local Breakout, the loopback traversal scenario is excluded.

loopback traversal scenario: for the Roaming Architecture for Voice over IMS with Local Breakout, the scenario where the II-NNI between the caller’s home network and the caller’s visited network is being traversed by an initial INVITE request from the caller’s home network to the caller’s visited network or any subsequent SIP message within the same dialogue on the same call leg.

home-to-visited request on roaming II-NNI: SIP request being sent from the callee’s home network to the callee’s visited network.

home routeing: the scenario when the caller’s home network routes a dialog creating SIP request directly to the callee’s home network without using the loopback traversal scenario.

visited-to-home request on roaming II-NNI: SIP request being sent from the caller’s visited network to the caller’s home network.

home-to-visited response on roaming II-NNI: SIP response being sent from the caller’s home network to the caller’s visited network.

visited-to-home response on roaming II-NNI: SIP response being sent from the callee’s visited network to the callee’s home network.

For the purposes of the present document, the following terms and definitions given in 3GPP TS 23.292 [120] apply:

MSC Server enhanced for ICS

For the purposes of the present document, the following terms and definitions given in 3GPP TS 23.237 [159] apply:

MSC server enhanced for SRVCC

For the purposes of the present document, the following terms and definitions given in 3GPP TS 24.237 [131] apply:

MSC server enhanced for dual radio

For the purposes of the present document, the following term and definition given in 3GPP TS 23.218 [219] apply:

Standalone transaction

3.2 Symbols

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

I2 Reference point between the MSC Server enhanced for ICS and the home IMS

Ici Reference Point between an IBCF and another IBCF belonging to a different IM CN subsystem network

Ix Reference Point between an IBCF and TrGW

Izi Reference Point between a TrGW and another TrGW or media handling node belonging to a different IM CN subsystem network

Mi Reference Point between a BGCF and CSCF

Mm Reference Point between a CSCF/BGCF/IMS ALG and an IP multimedia network

Mw Reference Point between a CSCF and another CSCF

Mx Reference Point between a CSCF/BGCF/MSC Server enhanced for ICS/ MSC Server enhanced for SRVCC / MSC server enhanced for dual radio and IBCF

3.3 Abbreviations

For the purposes of the present document, the abbreviations given in 3GPP 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 3GPP TR 21.905 [1].

18x A SIP status-code in the range 180 through 189

2xx A SIP status-code in the range 200 through 299

3PTY Three-Party

3xx A SIP status-code in the range 300 through 399

4xx A SIP status-code in the range 400 through 499

5GS 5G System

5xx A SIP status-code in the range 500 through 599

6xx A SIP status-code in the range 600 through 699

ACR Anonymous Communication Rejection

AOC Advice Of Charge

AS Application Server

ATCF Access Transfer Control Function

B2BUA Back 2 Back User Agent

BGCF Breakout Gateway Control Function

CAT Customized Alerting Tone

CB Communication Barring

CCBS Completion of Communications to Busy Subscriber

CCNL Completion of Communications on Not Logged-in

CCNR Communication Completion on No Reply

CDIV Communication Diversion

CONF Conference

CRS Customized Ringing Signal

CSCF Call Session Control Function

CW Communication Waiting

DRVCC Dual Radio Voice Call Continuity

eCNAM Enhanced Calling Name

E-CSCF Emergency CSCF

ECT Explicit Communication Transfer

FA Flexible Alerting

GRUU Globally Routable User agent URIs

HOLD Communication HOLD

IBCF Interconnection Border Control Function

ICB Incoming Communication Barring

ICID IMS Charging Identifier

ICS IMS Centralized Services

I-CSCF Interrogating CSCF

II-NNI Inter-IMS Network to Network Interface

IM Instant Messaging

IMS-ALG IMS Application Level Gateway

IOI Inter Operator Identifier

IUT Inter UE Transfer

MBMS Multimedia Broadcast Multicast Service

MCData Mission Critical Data

MCID Malicious Communication IDentification

MCPTT Mission Critical Push-To-Talk

MCVideo Mission Critical Video

MiD Multi-iDentity

MMTEL Multimedia Telephony

MPS Multimedia Priority Service

MRB Media Resource Broker

MRFC Media Resource Function Controller

MRFP Multimedia Resource Function Processor

MSD Minimum Set of Data

MSRP Message Session Relay Protocol

MTSI Multimedia Telephony Service for IMS

MuD Multi-Device

MWI Message Waiting Indication

NA(P)T-PT Network Address (Port-Multiplexing) Translation-Protocol Translation

NNI Network to Network Interface

OCB Outgoing Communication Barring

OIP Originating Identification Presentation

OIR Originating Identification Restriction

OMA Open Mobile Alliance

OMR Optimal Media Routeing

P-CSCF Proxy CSCF

PCF Policy Control Function

PCRF Policy and Charging Rules Function

PNM Personal Network Management

PRES Presence

PSAP Public Safety Answering Point

PSI Public Service Identity

RLOS Restricted Local Operator Services

RTT Round-trip Time

S-CSCF Serving CSCF

SRVCC Single Radio Voice Call Continuity

STN Session Transfer Number

TIP Terminating Identification Presentation

TIR Terminating Identification Restriction

TRF Transit and Roaming Function

TrGW Transition Gateway

UDM Unified Data Management

vSRVCC Single Radio Video Call Continuity