Content for TS 29.332 Word version: 17.0.0

3.1 Definitions 3.2 Symbols 3.3 Abbreviations
...

1 Scope p. 4

The present document describes the protocol to be used on the Media Gateway Control Function (MGCF) - IM Media Gateway (IM-MGW) interface. This interface provides the Media Gateway Control for interworking between the IP Multimedia Subsystem (IMS) and CS domain (ISUP, BICC and SIP-I). The basis for this protocol is the H.248 protocol as specified in ITU-T. The IMS architecture is described in TS 23.228. The interaction of the MGCF-IM MGW interface signalling procedures in relation to the SIP, and BICC/ISUP signalling at the MGCF are described in TS 29.163.

The interaction of the MGCF-IM MGW interface signalling procedures in relation to the IMS SIP and SIP-I on Nc at the MGCF are described in TS 29.235.

This specification describes the application of H.248 on the Mn interface. Required extensions use the H.248 standard extension mechanism. In addition certain aspects of the base protocol H.248 are not needed for this interface and thus excluded by this profile.

In addition this profile provides support for PSTN/ISDN Emulation as required by ETSI TISPAN.

The specification contains a normative Annex defining the H.248.1 Profile in accordance with ITU-T recommendations for H.248.1 applications. Where there exists any contradiction between the normative Annex A and the rest of the specification, the Normative Annex shall take precedence. The main body of the specification provides an introduction to the use of the profile for the Mn interface and introduces any specific functionality (e.g. new packages) associated to the Mn.

2 References p. 4

The following documents contain provisions which, through reference in this text, constitute provisions of the present document.

References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
For a specific reference, subsequent revisions do not apply.
For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.

[1]

TS 23.228: "IP Multimedia Subsystem (IMS); Stage 2".

[2]

TS 29.007: "General requirements on interworking between the Public Land Mobile Network (PLMN) and the Integrated Services Digital Network (ISDN) or Public Switched Telephone Network (PSTN)".

[3]

TS 29.205: "Application of Q.1900 series to Bearer Independent CS Network architecture; Stage 3".

[4]

TS 29.163: "Interworking between the IM CN subsystem and CS networks - Stage 3".

[5]

TS 29.232: "Media Gateway Controller (MGC); Media Gateway (MGW) interface; Stage 3".

[6]

TS 26.226: "Cellular Text Telephone Modem; General Description".

[7]

TS 26.103: "Speech codec list for GSM and UMTS".

[8] Void

[9]

ITU-T Recommendation H.248.1 (05/2002): "Gateway Control Protocol: Version 2" including the Corrigendum1 for Version 2 (03/04).

[10]

ITU-T Recommendation H.248.8 (09/2005): "Error Codes and Service Change Reason Description".

[11]

ITU-T Recommendation H.248.2 (01/2005): "Facsimile, text conversation and call discrimination packages".

[12]

ITU-T Recommendation H.248.10 (07/2001): "Media Gateway Resource Congestion Handling Package".

[13] Void

[14]

ITU-T Recommendation Q.1950 (12/2002): "Call Bearer Control Protocol".

[15]

RFC 2960: "Stream Control Transmission Protocol".

[16]

RFC 4867: "RTP Payload Format and File Storage Format for the Adaptive Multi-Rate (AMR) and Adaptive Multi-Rate Wideband (AMR-WB) Audio Codecs".

[17]

RFC 4566: "SDP: Session Description Protocol".

[18]

RFC 2833: "RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals".

[19] Void

[20] Void

[21]

TS 29.415: "Core Network Nb Interface User Plane Protocols".

[22]

TS 23.153: "Out of band transcoder control".

[23]

RFC 768: "User Datagram Protocol".

[24]

RFC 3332: "Signaling System 7 (SS7) Message Transfer Part 3 (MTP3) - User Adaptation Layer (M3UA)".

[25]

TS 29.202: "SS7 Signalling Transport in Core Network".

[26]

ITU-T Recommendation H.248.7 (03/2004): "Generic Announcement Package".

[27]

ITU-T Recommendation H.248.36 (09/2005): "Hanging Termination Detection Package ".

[28]

ITU-T Recommendation H.248.11 (11/2002): "Media gateway overload control package".

[29]

ITU-T Recommendation H.248.14 (03/2009): "Inactivity timer package".

[30]

ITU-T Recommendation H.248.45 (05/2006): "MGC Information Package".

[31] Void

[32]

RFC 3555: "MIME Type Registration of RTP Payload Formats".

[33]

RFC 3551: "RTP Profile for Audio and Video Conferences with Minimal Control".

[34] Void

[35]

RFC 4040: "RTP Payload Format for a 64 kbit/s Transparent Call".

[36]

RFC 3389: "Real-time Transport Protocol (RTP) Payload for Comfort Noise (CN)".

[37]

ITU-T Recommendation V.152 (01/2005): "Procedures for supporting voice-band data over IP networks" including Corrigendum 1.

[38]

ITU-T Recommendation H.248.4 (12/2009): "Gateway control protocol: Transport over Stream Control Transmission Protocol (SCTP)".

[39]

RFC 3556: "Session Description Protocol (SDP) Bandwidth Modifiers for RTP Control Protocol (RTCP) Bandwidth".

[40]

TR 21.905: "Vocabulary for 3GPP Specifications".

[41]

ITU-T Recommendation H.248.12 (07/2001): "Gateway control protocol: H.248.1 packages for H.323 and H.324 interworking".

[42]

ITU-T Recommendation H.248.12 Amendment 2 (08/2007): "Gateway control protocol: H.248.1 packages for H.323 and H.324 interworking Amendment 2: Transport Mechanism".

[43]

RFC 3309: "Stream Control Transmission Protocol (SCTP) Checksum Change".

[44]

ITU-T Recommendation H.248.41 (05/2006): "IP Domain Connection package".

[45] Void

[46]

ITU-T Recommendation H.248.72 (12/2009): "Gateway control protocol: ITU-T H.248 support for media-oriented negotiation acceleration (MONA)".

[47]

TS 29.235: "Interworking between SIP-I based circuit-switched core network and other networks".

[48]

TS 23.231: "SIP-I based circuit-switched core network; Stage 2".

[49]

ITU-T Recommendation H.248.71 (02/2010): "Gateway Control Protocol: RTCP support packages".

[50]

RFC 4103: "RTP Payload for Text Conversation".

[51]

ITU-T Recommendation T.140: "Text conversation presentation protocol".

[52]

RFC 4102: "Registration of the text/red MIME Sub-Type".

[53]

RFC 2198: "RTP Payload for Redundant Audio Data".

[54]

ITU-T Recommendation V.18 (11/00): "Operational and interworking requirements for DCEs operating in the text telephone mode" including V.18 (2000) Amendment 1 (11/02): "Harmonization with ANSI TIA/EIA-825 (2000) text phones".

[55]

ITU-T Recommendation G.168 (03/2009): "Digital network echo cancellers".

[56] Void

[57] Void

[58] Void

[59]

RFC 4145: "TCP-Based Media Transport in the Session Description Protocol (SDP)".

[60]

RFC 4585: "Extended RTP Profile for Real-time Transport Control Protocol (RTCP) - Based Feedback (RTP/AVPF)".

[61]

ITU-T Recommendation X.690: "ASN.1 encoding rules: Specification of Basic Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules (DER)".

[62]

TS 26.114: "IP Multimedia Subsystem (IMS); Multimedia Telephony; Media handling and interaction".

[63]

TS 22.153: "Multimedia Priority Service".

[64]

ITU-T Recommendation H.248.52 (06/2008): "Gateway control protocol: QoS support packages".

[65]

ITU-T Recommendation T.38 (09/2010): "Procedures for real-time Group 3 facsimile communication over IP networks".

[66]

ITU-T Recommendation H.248.82 (03/2013): "Gateway control protocol: Explicit Congestion Notification Support".

[67]

ITU-T Recommendation H.248.50 (2010) Corrigendum 1 (02/12): "Gateway control protocol: NAT traversal toolkit packages".

[68] Void.

[69]

TS 24.229: "IP Multimedia Call Control Protocol based on SIP and SDP".

[70]

RFC 5939: "Session Description Protocol (SDP) Capability Negotiation".

[71]

ITU-T Recommendation H.248.80 (01/2014): "Gateway control protocol: Usage of the revised SDP offer/answer model with ITU-T H.248".

[72]

RFC 8445: "Interactive Connectivity Establishment (ICE): A Protocol for Network Address Translator (NAT) Traversal".

[73]

RFC 8839: "Session Description Protocol (SDP) Offer/Answer Procedures for Interactive Connectivity Establishment (ICE)".

3 Definitions, symbols and abbreviations p. 7

3.1 Definitions p. 7

For the purposes of the present document, the [following] terms and definitions [given in ... and the following] apply.

Context (H.248):

A context is an association between a number of Terminations. The context describes the topology (who hears/sees whom) and the media mixing and/or switching parameters if more than two terminations are involved in the association.

Package (H.248):

Different types of gateways may implement terminations which have differing characteristics. Variations in terminations are accommodated in the protocol by allowing terminations to have optional properties. Such options are grouped into packages, and a termination may realise a set of such packages.

Termination (H.248):

A termination is a logical entity on an MGW which is the source and/or sink of media and/or control streams. A termination is described by a number of characterising properties, which are grouped in a set of descriptors which are included in commands. Each termination has a unique identity (TerminationID).

Termination Property (H.248):

Termination properties are used to describe terminations. Related properties are grouped into descriptors. Each termination property has a unique identity (PropertyID).

For the purposes of the present document, the following terms and definitions as defined in TS 29.163 apply:

ICE lite

Full ICE

3.2 Symbols p. 8

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

Interface between the media gateway control function and the IMS media gateway.

3.3 Abbreviations p. 8

For the purposes of the present document, the following abbreviations given in TR 21.905 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.

AMR

Adaptive MultiRate

BICC

Bearer Independent Call Control

Core Network

Circuit-Switched

DTMF

Dual Tone Multi Frequency

Congestion Experienced

ECN

Explicit Congestion Notification

FFS

For further study

GSM

Global System for Mobile communications

ICE

Interactive Connectivity Establishment

IETF

Internet Engineering Task Force

IP Multimedia

IM-MGW

IP Multimedia Media Gateway

IMS

IP Multimedia Subsystem

Internet Protocol

ISDN

Integrated Services Digital Network

ISUP

ISDN User Part

MG/MGW

Media GateWay

MGC

Media Gateway Controller

MGCF

Media Gateway Control Function

MIME

Multipurpose Internet Mail Extensions

MPS

Multimedia Priority Service

n.a.

not applicable

PDH

Plesiochronous Digital Hierarchy

PES

PSTN/ISDN Emulation Subsystem

PSTN

Public Switched Telephone Network

Payload Type

(ETSI TISPAN NGN) Release 2

RFC

Request For Comment; this includes both discussion documents and specifications in the IETF domain

RTCP

RTP Control Protocol

RTP

Real-time Transport Protocol

SCTP

Stream Control Transmission Protocol

SDH

Synchronous Digital Hierarchy

SDP

Session Description Protocol

SDPCapNeg

SDP Capability Negotiation

SIP

Session Initiation Protocol

SONET

Synchronous Optical NETwork

Silence Suppression

SS7

Signalling System No. 7

STUN

Session Traversal Utilities for NAT

TDM

Time Division Multiplexing

TISPAN

Telecommunications and Internet converged Services and Protocols for Advanced Networking

TMGW

Trunking MGW

Technical Specification (3GPP, ETSI)

VBD

VoiceBand Data

4 UMTS capability set p. 9

4.1 Capability set |R8| p. 9

The support of the Mn interface capability set shall be identified by the Mn profile and support of this profile shall be indicated in ServiceChange procedure.

The mandatory parts of this capability set shall be used in their entirety whenever it is used within the H.248 profile. Failure to do so will result in a non-standard implementation.

ITU-T Recommendation H.248.1 (05/02) [9] is the basis for this Capability Set. The compatibility rules for packages, signals, events, properties and statistics and the H.248 protocol are defined in ITU-T Recommendation H.248.1 [9]. Their use or exclusion for this interface is clarified in clause 12.

5 Naming conventions p. 9

5.1 MGCF/IM-MGW naming conventions p. 9

The MGCF shall be named according to the naming structure of the underlying transport protocol which carries the H.248 protocol.

For further definition of the Termination Names see Clause A.6.

5.2 Void

6 Topology descriptor p. 9

No special behaviour, for definition of use see Clause A.5.

7 Transaction timers p. 9

No special behaviour, for definition of timers see Clause A.10.

8 Transport p. 9

Each implementation of the Mn interface should provide SCTP (as defined in RFC 2960 and as updated by RFC 3309), however other options are permitted within the profile. For further definition see Clause A.12.

9 Multiple Virtual MG. p. 9

The support of multiple virtual MGW outlined in the subclause "Multiple virtual MGW" in ITU-T Recommendation H.248.1 [9] is optional.