ETSI TS 129 334 V15.1.0 (2020-01)

TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
LTE;
IMS Application Level Gateway (IMS-ALG) - IMS Access
Gateway (IMS-AGW);
Iq Interface;
Stage 3
(3GPP TS 29.334 version 15.1.0 Release 15)

3GPP TS 29.334 version 15.1.0 Release 15 1 ETSI TS 129 334 V15.1.0 (2020-01)

Reference
RTS/TSGC-0429334vf10
Keywords
GSM,LTE,UMTS
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ETSI
3GPP TS 29.334 version 15.1.0 Release 15 2 ETSI TS 129 334 V15.1.0 (2020-01)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (https://ipr.etsi.org/).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
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Legal Notice
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities. These shall be
interpreted as being references to the corresponding ETSI deliverables.
The cross reference between 3GPP and ETSI identities can be found under http://webapp.etsi.org/key/queryform.asp.
Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI
3GPP TS 29.334 version 15.1.0 Release 15 3 ETSI TS 129 334 V15.1.0 (2020-01)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 6
1 Scope . 7
2 References . 8
3 Definitions, symbols and abbreviations . 12
3.1 Definitions . 12
3.2 Symbols . 12
3.3 Abbreviations . 12
4 Applicability . 13
4.1 Architecture . 13
5 Profile Description . 14
5.1 Profile Identification. 14
5.2 Summary . 14
5.3 Gateway Control Protocol Version . 15
5.4 Connection model. 15
5.5 Context attributes . 15
5.6 Terminations . 15
5.6.1 Termination names . 15
5.6.1.1 IP Termination . 15
5.6.1.1.1 ABNF Coding Overview and prose specification . 15
5.6.1.1.2 ASN.1 Coding Overview and prose specification . 16
5.6.2 Multiplexed terminations . 17
5.7 Descriptors . 17
5.7.1 TerminationState Descriptor . 17
5.7.2 Stream Descriptor . 18
5.7.2.0 General . 18
5.7.2.1 LocalControl Descriptor . 18
5.7.3 Events descriptor . 19
5.7.4 EventBuffer descriptor . 21
5.7.5 Signals descriptor . 21
5.7.6 DigitMap descriptor . 23
5.7.7 Statistics descriptor . 23
5.7.8 ObservedEvents descriptor . 23
5.7.9 Topology descriptor . 23
5.7.10 Error descriptor . 24
5.8 Command API . 27
5.8.1 Add . 27
5.8.2 Modify . 27
5.8.3 Subtract . 28
5.8.4 Move . 28
5.8.5 AuditValue . 28
5.8.6 AuditCapabilities . 28
5.8.7 Notify . 29
5.8.8 ServiceChange . 29
5.8.9 Manipulating and auditing context attribute s . 31
5.9 Generic command syntax and encoding . 31
5.10 Transactions . 31
5.11 Messages . 32
5.12 Transport . 32
5.13 Security . 33
5.14 Packages . 33
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5.14.1 Mandatory Packages . 33
5.14.2 Optional Packages . 35
5.14.3 Package usage information . 37
5.14.3.1 Generic (g) . 37
5.14.3.2 Base root (root) . 38
5.14.3.3 Differentiated Services (ds) . 39
5.14.3.4 Gate Management (gm) . 39
5.14.3.5 Traffic management (tman) . 41
5.14.3.6 Inactivity Timer (it) . 42
5.14.3.7 IP Domain Connection (ipdc) . 42
5.14.3.8 Media Gateway Overload Control Package (ocp) . 43
5.14.3.9 Hanging Termination Detection (hangterm) . 43
5.14.3.10 Media Gateway Resource Congestion handling Package (chp) . 44
5.14.3.11 IP Realm Availability (ipra) . 44
5.14.3.12 IP NAPT Traversal (ipnapt) . 45
5.14.3.13 RTCP Handling Package (rtcph) . 45
5.14.3.14 Application Data Inactivity Detection (adid) . 46
5.14.3.15 Explicit Congestion Notification for RTP-over-UDP Support (ecnrous) . 47
5.14.3.16 MG Act-as STUN Server (mgastuns) . 49
5.14.3.17 Originate STUN Continuity Check (ostuncc) . 50
5.14.3.18 TCP basic connection control (tcpbcc) . 51
5.14.3.19 TLS basic session control (tlsbsc) . 52
5.14.3.20 Stream endpoint interlinkage (seplink) . 53
5.14.3.21 MG located Bearer Level ALG (mgbalg) . 54
5.14.3.22 STUN Consent Freshness (stnconfres). 54
5.14.3.23 Media Grouping (mgroup) . 56
5.14.3.24 SCTP basic connection control package (sctpbcc) . 57
5.14.3.25 SCTP Re-configuration Stream Reset (sctpreset) . 58
5.15 Mandatory support of SDP and Annex C information elements . 60
5.16 Optional support of SDP and Annex C information elements . 63
5.17 Procedures . 68
5.17.1 Formats and Codes . 68
5.17.2 Call Related Procedures . 75
5.17.2.1 General . 75
5.17.2.2 Reserve AGW Connection Point . 76
5.17.2.3 Configure AGW Connection Point . 82
5.17.2.4 Reserve and Configure AGW Connection Point . 91
5.17.2.5 Release AGW Termination . 100
5.17.2.6 Termination Heartbeat Indication . 100
5.17.2.7 IP Bearer Released . 101
5.17.2.8 Media Inactivity Notification . 101
5.17.2.9 Change Through Connection . 102
5.17.2.10 Change Flow Direction . 102
5.17.2.11 ECN Failure Indication . 103
5.17.2.12 ICE Connectivity Check Result Notification . 103
5.17.2.13 ICE New Peer Reflexive Candidate Notification . 103
5.17.2.14 Notify TCP connection establishment Failure Indication . 104
5.17.2.15 Notify (D)TLS session establishment Failure Indication . 104
5.17.2.16 STUN Consent Freshness Test Failure Notification . 105
5.17.2.17 Notify SCTP Stream Reset . 105
5.17.2.18 Notify SCTP Stream Reset Result . 106
5.17.3 Non-Call Related Procedures . 106
5.17.3.1 General . 106
5.17.3.2 IMS-AGW Out Of Service . 107
5.17.3.3 IMS-AGW Communication Up . 108
5.17.3.4 IMS-AGW Restoration . 108
5.17.3.5 IMS-AGW Register . 109
5.17.3.6 IMS-AGW Re-Register . 109
5.17.3.7 IMS-ALG Ordered Re-register . 110
5.17.3.8 IMS-ALG Restoration . 110
5.17.3.9 IMS-ALG Out of Service . 111
5.17.3.10 Audit Value . 111
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5.17.3.11 Command Rejected . 113
5.17.3.12 AGW Capability Change . 113
5.17.3.13 IMS-AGW Resource Congestion Handling – Activate . 113
5.17.3.14 IMS-AGW Resource Congestion Handling – Indication . 114
5.17.3.15 Inactivity Timeout – Activation . 114
5.17.3.16 Inactivity Timeout – Indication . 115
5.17.3.17 Realm Availability Change – Activation . 115
5.17.3.18 Realm Availability Change – Indication . 115
5.17.3.19 Termination Out Of Service . 116
Annex A (informative): Change history . 117
History . 120

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3GPP TS 29.334 version 15.1.0 Release 15 6 ETSI TS 129 334 V15.1.0 (2020-01)
Foreword
rd
This Technical Specification has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.

ETSI
3GPP TS 29.334 version 15.1.0 Release 15 7 ETSI TS 129 334 V15.1.0 (2020-01)
1 Scope
The present document describes the protocol to be used on the IMS Application Level Gateway (ALG) – IMS Access
Gateway (IMS-AGW) interface. The basis for this protocol is the H.248 protocol as specified in ITU-T. The IMS
architecture is described in 3GPP TS 23.228 [2]. The underlying reference model and stage 2 information is described
in Annex G of 3GPP TS 23.228 [2] and in 3GPP TS 23.334 [23].
This specification describes the application of H.248 on the Iq interface (see Figure 1). 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.
P-CSCF
Gm
IMS-ALG
Scope of this
Iq
specification.
IP-CAN
NAT
UE
IMS Access Gateway
Media
Figure 1: Reference model for IMS access
The reference model for the IMS-ALG and the IMS-AGW supporting the ATCF/ATGW function is shown in Figure 1a
below.
Gm
P-CSCF
IMS
Mw/Mx
I/S-CSCF
Mw/I2
IMS-ALG
SCC AS
MSC
(ATCF)
Server
CS
Mc
access
CS-
Iq
MGW
UE
PS-to-CS Access
Transfer
NAT
PS Mb
access
Mb
IMS-AGW (ATGW)
Mb
Figure 1a: Reference model for IMS-ALG/IMS-AGW with ATCF/ATGW function
See 3GPP TS 23.237 [38] clause 5.2 for a comprehensive description of the reference model.
The reference model for the P-CSCF enhanced for WebRTC (eP-CSCF) and the IMS-AGW enhanced for WebRTC
(eIMS-AGW) to support WebRTC client access to IMS is shown in Figure 1b as below, see 3GPP TS 23.228 [2]
Annex U for a comprehensive description of the reference model.
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W4
WWSF WAF
W1
W5
WIC
W2 Mw
eP-CSCF
I/S-CSCF
IMS-ALG
I
Rx
P P
N
- C
A
Iq
C E
H/V-PCRF
T
A F
N Gx
UE
eIMS-AGW
W3
Figure 1b: Reference Architecture for eP-CSCF/eIMS-AGW supporting WebRTC access to IMS
NOTE: The presence of dashed elements in the figure depends on the configuration.
PCC functional elements are present only for EPC access with QoS.
The corresponding PCC elements for fixed access are also optionally supported but not shown.
The NAT in figure 1b is meant for non-cellular access to IMS.
2 References
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] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 23.228: "IP Multimedia Subsystem (IMS); Stage 2".
[3] ETSI TS 183 018 V3.5.1 (2009-07): "Telecommunications and Internet converged Services and
Protocols for Advanced Networking (TISPAN); Resource and Admission Control: H.248 Profile
Version 3 for controlling Border Gateway Functions (BGF) in the Resource and Admission
Control Subsystem (RACS); Protocol specification".
[4] ITU-T Recommendation H.248.37 (06/2008): "Gateway control protocol: IP NAPT traversal
package".
[5] ITU-T Recommendation H.248.57 (10/2014): "Gateway control protocol: RTP Control Protocol
Package".
[6] ITU-T Recommendation H.248.43 (06/2008): "Gateway control protocol: Gate Management and
Gate Control packages".
[7] ITU-T Recommendation H.248.53 (03/2009): "Gateway control protocol: Traffic management
packages".
[8] ITU-T Recommendation H.248.41 Amendment 1 (06/2008): "Gateway control protocol: IP
domain connection package: IP Realm Availability Package".
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[9] ITU-T Recommendation H.248.36 (09/2005): "Gateway control protocol: Hanging Termination
Detection package".
[10] ITU-T Recommendation H.248.1 (05/2002): "Gateway Control Protocol: Version 2" including the
Corrigendum1 for Version 2 (03/04).
[11] ITU-T Recommendation H.248.14 (03/2009): "Gateway control protocol: Inactivity timer
package".
[12] ITU-T Recommendation H.248.52 (06/2008): "Gateway control protocol: QoS support packages".
[13] ITU-T Recommendation H.248.11 (11/2002): "Gateway control protocol: Media gateway overload
control package".
Inclusive Corrigendum 1 (06/2008) to H.248.11 " Gateway control protocol: Media gateway
overload control package: Clarifying MG-overload event relationship to ADD commands".
[14] ITU-T Recommendation H.248.10 (07/2001): "Media gateway resource congestion handling
package".
[15] IETF RFC 5234 (2008): "Augmented BNF for Syntax Specifications: ABNF".
[16] IETF RFC 4960 (2007): "Stream control transmission protocol".
[17] IETF RFC 4566 (2006): "SDP: Session Description Protocol".
[18] IETF RFC 4975 (2007): "The Message Session Relay Protocol (MSRP)".
[19] IETF RFC 3551 (2003): "RTP Profile for Audio and Video Conferences with Minimal Control".
[20] IETF RFC 4145 (2005): "TCP-Based Media Transport in the Session Description Protocol (SDP)".
[21] IETF RFC 3605 (2003): "Real Time Control Protocol (RTCP) attribute in Session Description
Protocol (SDP)".
[22] ITU-T Recommendation X.690 (11/2008): "ASN.1 encoding rules: Specification of Basic
Encoding Rules (BER), Canonical Encoding Rules (CER) and Distinguished Encoding Rules
(DER)".
[23] 3GPP TS 23.334: "IMS Application Level Gateway (IMS-ALG) – IMS Access Gateway (IMS-
AGW) interface: Procedures Descriptions".
[24] ITU-T Recommendation H.248.40 (01/2007): "Gateway control protocol: Application Data
Inactivity Detection package".
[25] IETF RFC 4585 (2006): "Extended RTP Profile for Real-time Transport Control Protocol (RTCP)
- Based Feedback (RTP/AVPF)".
[26] 3GPP TS 26.114: "IP Multimedia Subsystem (IMS); Multimedia telephony; Media handling and
interaction".
[27] 3GPP TS 33.210: "Technical Specification Group Services and System Aspects;3G Security;
Network Domain Security; IP Network Layer Security".
[28] IETF RFC 3556 (2003): "Session Description Protocol (SDP) Bandwidth Modifiers for RTP
Control Protocol (RTCP) Bandwidth".
[29] IETF RFC 4568 (2006): "Session Description Protocol (SDP) Security Descriptions for Media
Streams".
[30] IETF RFC 3711 (2004): "The Secure Real-time Transport Protocol (SRTP)".
[31] IETF RFC 5124 (2008): "Extended Secure RTP Profile for Real-time Transport Control Protocol
(RTCP)-Based Feedback (RTP/SAVPF)".
[32] IETF RFC 2216 (1997): "Network Element Service Specification Template".
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[33] Supplement 7 to ITU-T H-series Recommendations H.Sup7 (05/2008):" Gateway control protocol:
Establishment procedures for the H.248 MGC-MG control association".
[34] 3GPP TS 33.328: "IMS Media Plane Security".
[35] Void
[36] Void
[37] Void
[38] 3GPP TS 23.237: "IP Multimedia subsystem (IMS) Service Continuity; Stage 2".
[39] 3GPP TS 22.153: "Multimedia Priority Service".
[40] ITU-T Recommendation H.248.82 (03/2013): "Gateway control protocol: Explicit Congestion
Notification Support".
[41] IETF RFC 5285 (2008): "A General Mechanism for RTP Header Extensions".
[42] IETF RFC 6236: "Negotiation of Generic Image Attributes in the Session Description Protocol
(SDP)".
[43] Draft ITU-T Recommendation H.248.50 (2015): "Gateway control protocol: NAT traversal toolkit
packages".
Editor's Note: The above document cannot be formally referenced until it is published as an ITU-T
Recommendation. The latest draft of revised H.248.50 is available from the following link:
http://wftp3.itu.int/av-arch/avc-site/2013-2016/1411_Seo/TD-08.zip
[44] IETF RFC 5245: "Interactive Connectivity Establishment (ICE): A Protocol for Network Address
Translator (NAT) Traversal for Offer/Answer Protocols".
[45] 3GPP TS 24.229: "IP Multimedia Call Control Protocol based on SIP and SDP".
[46] ITU-T Recommendation H.248.84 (07/2012): "Gateway control protocol: NAT traversal for peer-
to-peer services".
[47] ITU-T Recommendation H.248.89 (10/2014): "Gateway control protocol: TCP support packages".
[48] ITU-T Recommendation H.248.90 (10/2014): "Gateway control protocol: ITU-T H.248 packages
for control of transport security using transport layer security (TLS)".
[49] ITU-T Recommendation H.248.92 (10/2014): "Gateway control protocol: Stream endpoint
interlinkage package".
[50] ITU-T Recommendation H.248.93 (10/2014): "Gateway control protocol: ITU-T H.248 support
for control of transport security using the datagram transport layer security (DTLS) protocol".
[51] IETF RFC 793: "Transmission Control Protocol – DARPA Internet Program – Protocol
Specification".
[52] IETF RFC 4582: "The Binary Floor Control Protocol (BFCP)".
[53] IETF RFC 5246: "The Transport Layer Security (TLS) Protocol Version 1.2".
[54] IETF draft-schwarz-mmusic-sdp-for-gw-04: "SDP codepoints for gateway control".
Editor's Note: The above document cannot be formally referenced until it is published as an RFC.
[55] IETF RFC 8122: "Connection-Oriented Media Transport over the Transport Layer Security (TLS)
Protocol in the Session Description Protocol (SDP)".
[56] Draft ITU-T Recommendation H.248.78 (Ed. 0.9, 11/2014): "Gateway control protocol: Bearer-
level message backhauling and application level gateway".
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Editor's Note: The above document is currently under revision by ITU-T. The latest output draft of the revised ITU-
T Recommendation H.248.78 is available from the following link:
http://wftp3.itu.int/av-arch/avc-site/2013-2016/1411_Seo/TD-09.zip.
[57] IETF RFC 6714: "Connection Establishment for Media Anchoring (CEMA) for the Message
Session Relay Protocol (MSRP)".
[58] IETF RFC 7675: "Session Traversal Utilities for NAT (STUN) Usage for Consent Freshness".
[59] IETF RFC 5761: "Multiplexing RTP Data and Control Packets on a Single Port".
[60] IETF RFC 5763: "Framework for Establishing a Secure Real-time Transport Protocol (SRTP)
Security Context Using Datagram Transport Layer Security (DTLS)".
[61] IETF RFC 5764: "Datagram Transport Layer Security (DTLS) Extension to Establish Keys for the
Secure Real-time Transport Protocol (SRTP)".
[62] IETF RFC 4573: "MIME Type Registration for RTP Payload Format for H.224".
[63] ITU-T Recommendation H.224 (01/2005): "A real time control protocol for simplex applications
using the H.221 LSD/HSD/MLP channels".
[64] ITU-T Recommendation H.281 (11/1994): "A far end camera control protocol for
videoconferences using H.224".
[65] ITU-T Recommendation H.248.96 (11/2015): "Gateway control protocol: H.248 support for
control of SCTP bearer connections".
[66] ITU-T Recommendation H.248.97 (11/2015): "Gateway control protocol: H.248 support for
control of SCTP bearer connections".
[67] ITU-T Recommendation H.248.94 (11/2015): "Gateway control protocol: Web-based real-time
communication services – H.248 protocol support and profile guidelines".
[68] IETF draft-ietf-mmusic-sctp-sdp-26: "Session Description Protocol (SDP) Offer/Answer
Procedures For Stream Control Transmission Protocol (SCTP) over Datagram Transport Layer
Security (DTLS) Transport".
Editor's note: The above document cannot be formally referenced until it is published as an RFC.
[69] IETF draft-ietf-mmusic-data-channel-sdpneg-06: "SDP-based Data Channel Negotiation".
Editor's note: The above document cannot be formally referenced until it is published as an RFC.
[70] IETF draft-ietf-mmusic-msrp-usage-data-channel-13: "MSRP over Data Channels".
Editor's note: The above document cannot be formally referenced until it is published as an RFC.
[71] ITU-T Recommendation H.248.88 (01/2014): "Gateway control protocol: RTP topology
dependent RTCP handling by ITU-T H.248 media gateways with IP terminations".
[72] IETF RFC 5939: "Session Description Protocol (SDP) Capability Negotiation".
[73] ITU-T Recommendation H.248.80 (01/2014): "Gateway control protocol: Usage of the revised
SDP offer/answer model with ITU-T H.248".
[74] IETF draft-ietf-mmusic-mux-exclusive-11: "Indicating Exclusive Support of RTP/RTCP
Multiplexing using SDP".
Editor's note: The above document cannot be formally referenced until it is published as an RFC.
[75] ITU-T Recommendation T.140 (02/98): "Text conversation presentation protocol".
[76] IETF RFC 4103: "RTP Payload for Text Conversation".
[77] IETF draft-ietf-mmusic-t140-usage-data-channel-06: "T.140 Real-time Text Conversation over
WebRTC Data Channels".
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Editor's note: The above document cannot be formally referenced until it is published as an RFC.
[78] IETF RFC 5104: "Codec Control Messages in the RTP Audio-Visual Profile with Feedback
(AVPF)".
[79] IETF RFC 7728: "RTP Stream Pause and Resume".
3 Definitions, symbols and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply.
Address: term used for "network address" (IP address)
End-to-access edge security: media protection extending between an IMS UE and the first IMS core network node in
the media path without being terminated by any intermediary node.
Port: term used for "transport port" (L4 port).
Transcoding: transcoding in general is the translation from one type of encoded media format to another different
media format, e.g. G.711 A-law to μ-law or vice versa, G.729 to AMR with 4.75 rate.
NOTE 1: The definition of "transcoding" is according clause 3.10 of ITU-T Recommendation V.152 [23].
NOTE 2: Transcoding belongs to the category of "media aware" IP-to-IP interworking.
Transparent Forwarding: media gateway packet forwarding behaviour with the characteristic of Lx-PDU integrity.
This is a unidirectional characteristic of an Lx-PDU flow.
NOTE 3: The definition is according clause 3.2.10 of ITU-T Recommendation H.248.88 [71].
NOTE 4: The semantic covers both traffic directions when applied on H.248 Streams (due to their inherent
characteristic of bidirectionality).
Transport Address: term used for the combination of a Network Address and a Transport Port.
For the purposes of the present document, the following terms and definitions as defined in 3GPP TS 23.334 [23] apply:
ICE lite
Full ICE.
3.2 Symbols
For the purposes of the present document, the following symbols apply:
Iq Interface between the IMS Application Level Gateway (ALG) (IMS-ALG) and the IMS Access
Gateway (IMS-AGW)
3.3 Abbreviations
For the purposes of the present document, the abbreviations defined in 3GPP TR 21.905 [1] apply, with the following
additions. An abbreviation defined in the present document takes precedence over the definition of the same
abbreviation, if any, in 3GPP TR 21.905 [1].
ABNF Augmented Backus-Naur Form
ATCF Access Transfer Control Function
ATGW Access Transfer Gateway
ETSI
3GPP TS 29.334 version 15.1.0 Release 15 13 ETSI TS 129 334 V15.1.0 (2020-01)
B-ALG Bearer Level Application-Level Gateway
BFCP Binary Floor Control Protocol
CCM Codec Control Messages
CVO Coordination of Video Orientation
DSCP Differentiated Service Code Point
e2ae End-to-Access-Edge (security model)
ECN Explicit Congestion Notification
eIMS-AGW IMS Access Gateway enhanced for WebRTC
eP-CSCF P-CSCF enhanced for WebRTC
FECC Far End Camera Control
FIR Full Intra Request
GTT Global Text Telephony
ICE Interactive Connectivity Establishment
IMS-AGW IMS Access Gateway
IMS-ALG IMS Application Level Gateway
IP Internet Protocol
LD Local Descriptor (H.248 protocol element)
MG Media Gateway
MGC Media Gateway Controller
MPS Multimedia Priority Service
MSRP Message Session Relay Protocol
NA Not Applicable
NAPT Network Address and Port Translation
NAPT-PT NAPT and Protocol Translation
NAT Network Address Translation
RD Remote Descriptor (H.248 protocol element)
ROI Region of Interest
RTCP RTP Control Protocol
SCTP Stream Control Transport Protocol
SDP Session Description Protocol
SDPCapNeg SDP Capability Negotiation
SRVCC Single Radio Voice Call Continuity
STUN Session Traversal Utilities for NAT
TCP Transmission Control Protocol
TLS Transport Layer Security (protocol)
TMMBN Temporary Maximum Media Stream Bit Rate Notification
TMMBR Temporary Maximum Media Stream Bit Rate Request
ToS Type-of-Service
TISPAN Telecommunications and Internet converged Services and Protocols for Advanced Networking
WebRTC Web Real Time Communication
WIC WebRTC IMS Client
WWSF WebRTC Web Server Function
4 Applicability
The support of the Iq interface capability set shall be identified by the H.248 Iq profile and support of this profile shall
be indicated in H.248 ServiceChange procedure (during the (re-)registration phase(s)).
4.1 Architecture
See Annex G and Annex U of 3GPP TS 23.228 [2].
ETSI
3GPP TS 29.334 version 15.1.0 Release 15 14 ETSI TS 129 334 V15.1.0 (2020-01)
5 Profile Description
5.1 Profile Identification
Table 5.1.1: Profile Identification
Profile name: threegIq
Version: 5
5.2 Summary
This Profile describes the minimum mandatory settings and procedures required to fulfil the requirements of the Iq
interface (see 3GPP TS 23.334 [23]):
- allocation and translation of IP addresses and port numbers (NA(P)T and NA(P)T-PT);
- opening and closing gates (i.e. packets filtering depending on "IP address / port");
- remote NA(P)T traversal;
- policing of incoming traffic;
- QoS packet marking for outgoing traffic;
- IP realm/domain indication;
- Hanging termination detection; and
- RTCP handling;
and when ATCF/ATGW is supported:
- handover of bearer connections between PS and CS access networks;
- IP version interworking; and
- audio transcoding;
and when WebRTC is supported:
- interworking for WebRTC audio, video and optionally MSRP data between WebRTC clients and non-WebRTC
user equipment; and
- optionally transparent forwarding of WebRTC bearer traffic in case of end-to-end WebRTC calls between
WebRTC IMS clients.
In addition, optional settings and procedures are described which fulfil optional features and where supported, the
minimum mandatory setting
...