1、 International Telecommunication Union ITU-T H.248.81TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (05/2011) SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMSInfrastructure of audiovisual services Communication procedures Gateway control protocol: Guidelines on the use of the international emergency pr
2、eference scheme (IEPS) call indicator and priority indicator in ITU-T H.248 profiles Recommendation ITU-T H.248.81 ITU-T H-SERIES RECOMMENDATIONS AUDIOVISUAL AND MULTIMEDIA SYSTEMS CHARACTERISTICS OF VISUAL TELEPHONE SYSTEMS H.100H.199 INFRASTRUCTURE OF AUDIOVISUAL SERVICES General H.200H.219 Transm
3、ission multiplexing and synchronization H.220H.229 Systems aspects H.230H.239 Communication procedures H.240H.259Coding of moving video H.260H.279 Related systems aspects H.280H.299 Systems and terminal equipment for audiovisual services H.300H.349 Directory services architecture for audiovisual and
4、 multimedia services H.350H.359 Quality of service architecture for audiovisual and multimedia services H.360H.369 Supplementary services for multimedia H.450H.499 MOBILITY AND COLLABORATION PROCEDURES Overview of Mobility and Collaboration, definitions, protocols and procedures H.500H.509 Mobility
5、for H-Series multimedia systems and services H.510H.519 Mobile multimedia collaboration applications and services H.520H.529 Security for mobile multimedia systems and services H.530H.539 Security for mobile multimedia collaboration applications and services H.540H.549 Mobility interworking procedur
6、es H.550H.559 Mobile multimedia collaboration inter-working procedures H.560H.569 BROADBAND, TRIPLE-PLAY AND ADVANCED MULTIMEDIA SERVICES Broadband multimedia services over VDSL H.610H.619 Advanced multimedia services and applications H.620H.629 IPTV MULTIMEDIA SERVICES AND APPLICATIONS FOR IPTV Gen
7、eral aspects H.700H.719 IPTV terminal devices H.720H.729 IPTV middleware H.730H.739 IPTV application event handling H.740H.749 IPTV metadata H.750H.759 IPTV multimedia application frameworks H.760H.769 IPTV service discovery up to consumption H.770H.779 For further details, please refer to the list
8、of ITU-T Recommendations. Rec. ITU-T H.248.81 (05/2011) i Recommendation ITU-T H.248.81 Gateway control protocol: Guidelines on the use of the international emergency preference scheme (IEPS) call indicator and priority indicator in ITU-T H.248 profiles Summary Recommendation ITU-T H.248.81 provides
9、 guidelines on the use of the international emergency preference scheme (IEPS) call indicator and priority indicator in ITU-T H.248 profiles for ITU-T H.323 and NGN systems. These guidelines may be used by other standards development organizations (SDOs) when defining their profiles in support of pr
10、iority services, e.g., the emergency telecommunications service (ETS) and the multimedia priority service (MPS). History Edition Recommendation Approval Study Group 1.0 ITU-T H.248.81 2011-05-14 16 ii Rec. ITU-T H.248.81 (05/2011) FOREWORD The International Telecommunication Union (ITU) is the Unite
11、d Nations specialized agency in the field of telecommunications, information and communication technologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommenda
12、tions on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The appro
13、val of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administrati
14、on“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and complianc
15、e with the Recommendation is achieved when all of these mandatory provisions are met. The words “shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is re
16、quired of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intell
17、ectual Property Rights, whether asserted by ITU members or others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation.
18、However, implementers are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2012 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without th
19、e prior written permission of ITU. Rec. ITU-T H.248.81 (05/2011) iii Table of Contents Page 1 Scope 1 2 References. 2 3 Definitions 3 3.1 Terms defined elsewhere 3 3.2 Terms defined in this Recommendation . 3 4 Abbreviations and acronyms 3 5 Conventions 4 6 Relation to other ITU-T Recommendations .
20、4 6.1 Recommendation ITU-T E.106: International emergency preference scheme for disaster relief operations 4 6.2 Recommendation ITU-T Q.1950 Annex F: Call bearer control Emergency call indication 4 6.3 Recommendation ITU-T Q.1950 Annex G: Call bearer control International emergency preference scheme
21、 4 7 Functional requirements . 4 8 ITU-T H.248 profile specification guidelines 5 8.1 Profile identification . 5 8.2 Summary . 5 8.3 Gateway Control Protocol Version 5 8.4 Connection Model 5 8.5 Context Attributes 5 8.6 Terminations . 6 8.7 Descriptors 6 8.8 Command API 7 8.9 Generic command syntax
22、and encoding . 8 8.10 Transactions 8 8.11 Messages . 8 8.12 Transport . 8 8.13 Security . 8 8.14 Packages . 8 8.15 Mandatory support of SDP and ITU-T H.248.1 Annex C information elements 9 8.16 Optional support of SDP and ITU-T H.248.1 Annex C information elements 9 8.17 Procedures 9 Appendix I Over
23、all example traffic model for decomposed gateways . 11 I.1 Overview 11 I.2 Traffic processing stages model subcomponents 13 Bibliography. 15Rec. ITU-T H.248.81 (05/2011) 1 Recommendation ITU-T H.248.81 Gateway control protocol: Guidelines on the use of the international emergency preference scheme (
24、IEPS) call indicator and priority indicator in ITU-T H.248 profiles 1 Scope ITU-T H.248.1 defines the international emergency preference scheme (IEPS) call indicator and priority indicator in support of priority services, e.g., the emergency telecommunications service (ETS) and the multimedia priori
25、ty service (MPS). Use of the IEPS call indicator and priority indicator, as defined in ITU-T H.248.1, satisfies the ETS requirements of indicating an ETS context and carrying the priority level. Any prioritization of ITU-T H.248 procedures in the media gateway controller (MGC) and the transport of I
26、TU-T H.248 control signalling towards the media gateway (MG) is based on the identification of ETS. The IEPS call indicator, identifying an ETS call/session, indicates to the MG that the context is an ETS context and enables prioritization of ITU-T H.248 control signalling once received. In addition
27、, it enables prioritized resource allocation in the MG for an ETS context. The priority indicator, carrying the priority level, provides the MG with a means to distinguish different priority handling of resources on the MG when ETS is used. This Recommendation provides guidelines on the use of the I
28、EPS call indicator and priority indicator in ITU-T H.248 profiles for ITU-T H.323 and NGN systems. These guidelines may be used by other standards development organizations (SDOs) when defining their ITU-T H.248.1 profiles in support of priority services (e.g., ETS and the MPS). Further details on h
29、ow these guidelines are used by other networks are outside the scope of this Recommendation. It is up to other SDOs to decide their use when defining their profiles. ETS and IEPS are defined in ITU-T E.107 and ITU-T E.106, respectively. ETS and IEPS involve authority-to-authority communication. The
30、emergency indicator, as defined in ITU-T H.248.1, is used for identification of emergency calls (i.e., individual-to-authority communication). The IEPS call indicator is used for the identification of a priority call/session (e.g., ETS call/session, IEPS call/session), allowing differentiation from
31、an emergency call/session. The specification of profile procedures for the emergency indicator is outside the scope of this Recommendation. National regulators may implement ETS in various ways. This Recommendation describes an implementation where the IEPS call indicator and priority indicator are
32、supported. NOTE 1 National, regional or local emergency and public safety services, where an individual from the general public is seeking assistance (i.e., individual-to-authority communication), are outside the scope of this Recommendation. NOTE 2 b-ITU-T Q-Sup.53 provides the signalling requireme
33、nts to support the IEPS. It is also applicable for ITU-T H.248 entities, but does not indicate any requirement in addition to clause 7. NOTE 3 b-ITU-T Q-Sup.57 provides the signalling requirements to support the ETS in IP networks. It is also applicable for ITU-T H.248 entities, but does not indicat
34、e any requirement in addition to clause 7. 2 Rec. ITU-T H.248.81 (05/2011) 2 References The following ITU-T Recommendations and other references contain provisions which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated
35、were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recomme
36、ndations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. ITU-T E.106 Recommendation ITU-T E.106 (2003), International Emergency Preference Scheme (IEPS) for disaster relief operations. ITU-T E
37、.107 Recommendation ITU-T E.107 (2007), Emergency Telecommunications Service (ETS) and interconnection framework for national implementations of ETS. ITU-T H.225.0 Recommendation ITU-T H.225.0 (2009), Call signalling protocols and media stream packetization for packet-based multimedia communication
38、systems. ITU-T H.248.1 Recommendation ITU-T H.248.1 (2005), Gateway control protocol: Version 3, including its Amendment 2 (2009). ITU-T H.248.4 Recommendation ITU-T H.248.4 (2009), Gateway control protocol: Transport over Stream Control Transmission Protocol (SCTP). ITU-T H.248.10 Recommendation IT
39、U-T H.248.10 (2001), Gateway control protocol: Media gateway resource congestion handling package. ITU-T H.248.11 Recommendation ITU-T H.248.11 (2002), Gateway control protocol: Media gateway overload control package. ITU-T H.248.32 Recommendation ITU-T H.248.32 (2005), Gateway control protocol: Det
40、ailed congestion reporting package. ITU-T H.248.52 Recommendation ITU-T H.248.52 (2008), Gateway control protocol: QoS support packages. ITU-T H.248.54 Recommendation ITU-T H.248.54 (2007), Gateway control protocol: MPLS support package. ITU-T H.248.56 Recommendation ITU-T H.248.56 (2007), Gateway c
41、ontrol protocol: Packages for virtual private network support. ITU-T H.248.63 Recommendation ITU-T H.248.63 (2009), Gateway control protocol: Resource management packages. ITU-T H.323 Recommendation ITU-T H.323 (2009), Packet-based multimedia communications systems. ITU-T Q.1950 Recommendation ITU-T
42、 Q.1950 (2002), Bearer independent call bearer control protocol. ITU-T Q.1950 Amd.1 Recommendation ITU-T Q.1950 (2002) Amendment 1 (2006), New Annex G Call bearer control International Emergency Preference Scheme. Rec. ITU-T H.248.81 (05/2011) 3 3 Definitions 3.1 Terms defined elsewhere This Recomme
43、ndation uses the following term defined elsewhere: 3.1.1 emergency telecommunications service (ETS) ITU-T E.107: A national service providing priority telecommunications to the ETS authorized users in times of disaster and emergencies. 3.2 Terms defined in this Recommendation This Recommendation def
44、ines the following term: 3.2.1 subject to profile specification: When used, this term indicates that the ITU-T H.248 profile template section requires further specification by a profile specification. 4 Abbreviations and acronyms This Recommendation uses the following abbreviations: DSCP DiffServ Co
45、de Point ETS Emergency Telecommunications Service IEPS International Emergency Preference Scheme IP Internet Protocol ISUP ISDN User Part LSP Label Switched Path Lx Layer number MG Media Gateway MGC Media Gateway Controller MLPP Multi-Level Precedence and Pre-emption MPLS Multi-Protocol Label Switch
46、ing MPS Multimedia Priority Service N/A Not Applicable NGN Next Generation Network PHB Per-Hop Behaviour QoS Quality of Service RPH Resource Priority Header SCTP Stream Control Transport Protocol SDO Standard Development Organization SDP Session Description Protocol SIP Session Initiation Protocol V
47、PN Virtual Private Network 4 Rec. ITU-T H.248.81 (05/2011) 5 Conventions This Recommendation uses the term “ETS“ according to ITU-T E.107. When the term “ETS“ is used in this Recommendation, it also means other authority-to-authority priority services that may be using terminology other than ETS (e.
48、g., IEPS, MPS, etc.). 6 Relation to other ITU-T Recommendations The purpose of this clause is to identify possible relations (or not) to other ITU-T Recommendations and past work on ITU-T H.248 profiles. 6.1 Recommendation ITU-T E.106: International emergency preference scheme for disaster relief op
49、erations There is a link between ITU-T E.106 and ITU-T E.107 by a reference from ITU-T E.107, clause 7, item e) to ITU-T E.106, indicating that “IEPS could be used in such a scenario for interconnection of ETS national implementations“. 6.2 Recommendation ITU-T Q.1950 Annex F: Call bearer control Emergency call indication ITU-T Q.1950, Annex F defines call-dependent procedures for emergency call indication, based on the ITU-T H.248 Context Attribute Emergency I
