1、 International Telecommunication Union ITU-T J.162TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (11/2005) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS IPCablecom Network call signalling protocol for the delivery of time-critical services ove
2、r cable television networks using cable modems ITU-T Recommendation J.162 ITU-T Rec. J.162 (11/2005) i ITU-T Recommendation J.162 Network call signalling protocol for the delivery of time-critical services over cable television networks using cable modems Summary This Recommendation describes a prof
3、ile of an application programming interface, Media Gateway Controller Interface (MGCI), and a corresponding protocol, Media Gateway Control Protocol (MGCP), for controlling voice-over-IP (VoIP) embedded clients from external call control elements. The MGCP assumes a call control architecture where t
4、he call control “intelligence“ is outside the gateways and is handled by external call control elements. The profile, as described in this Recommendation, will be referred to as the Network-based Call Signalling (NCS) Protocol. Source ITU-T Recommendation J.162 was approved on 29 November 2005 by IT
5、U-T Study Group 9 (2005-2008) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. J.162 (11/2005) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is
6、a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Telecommunication Standardization Assembly (WTSA), which meets every four years, e
7、stablishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval 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
8、 standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. Compliance with this Recommendation is voluntary. However, th
9、e Recommendation may contain certain mandatory provisions (to ensure e.g., interoperability or applicability) and compliance 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 equival
10、ents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required 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 clai
11、med Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual 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 n
12、ot received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not represent the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2006 All rights r
13、eserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. J.162 (11/2005) iii CONTENTS Page 1 Scope 1 2 References. 1 2.1 Normative references 1 2.2 Informative references 2 3 Terms, definitions and abbreviations 3 3.1 Te
14、rms and definitions. 3 3.2 Abbreviations . 3 4 Conventions 3 5 Introduction 4 5.1 Relation with H.323 standards . 5 5.2 Relation with IETF standards. 5 5.3 Relation to RFC 3435 and ABNF Grammar 6 6 Media Gateway Controller Interface (MGCI) 6 6.1 Model and naming conventions 6 6.2 SDP use 14 6.3 Gate
15、way control functions 14 6.4 States, failover and race conditions 40 6.5 Return codes and error codes . 55 6.6 Reason codes 56 6.7 Use of local connection options and connection descriptors 57 7 Media gateway control protocol . 60 7.1 General description. 61 7.2 Command header 61 7.3 Response header
16、 formats 75 7.4 Session description encoding . 78 7.5 Transmission over UDP . 89 7.6 Piggybacking 91 7.7 Transaction identifiers and three-way handshake 92 7.8 Provisional responses . 93 8 Security. 94 Annex A Event packages 95 A.1 Line package. 95 A.2 FAX Package 102 Annex B Dynamic Quality of Serv
17、ice 140 Appendix I Example event package 148 iv ITU-T Rec. J.162 (11/2005) Page Appendix II Example command encodings 150 II.1 NotificationRequest 150 II.2 Notify 150 II.3 CreateConnection . 151 II.4 ModifyConnection 152 II.5 DeleteConnection (From the Call Agent). 153 II.6 DeleteConnection (From th
18、e Embedded Client) 153 II.7 DeleteConnection (Multiple Connections From the Call Agent). 154 II.8 AuditEndpoint 154 II.9 AuditConnection. 155 II.10 RestartInProgress 156 Appendix III Example call flow 157 Appendix IV Connection mode 163 Appendix V Compatibility information 167 Appendix VI Additional
19、 example event packages 168 Appendix VII Event packages 176 Appendix VIII Application of the NCS protocol to a SCN IPAT 183 VIII.1 Overview 183 VIII.2 IPAT architecture . 183 VIII.3 Electrical and physical interface requirements. 184 VIII.4 NCS package for V5 SCN protocol messages . 185 VIII.5 Provi
20、sioning configurations 193 VIII.6 European Line Package support . 193 VIII.7 Call flow examples. 194 Appendix IX Metering support for IPCablecom NCS 204 IX.1 Objectives. 204 IX.2 Automatic metering package 204 IX.3 Use cases Example call flows 207 IX.4 Terms 209 Appendix X ABNF Grammar for NCS. 211
21、BIBLIOGRAPHY 219 ITU-T Rec. J.162 (11/2005) 1 ITU-T Recommendation J.162 Network call signalling protocol for the delivery of time-critical services over cable television networks using cable modems 1 Scope This Recommendation describes a profile of an application programming interface, Media Gatewa
22、y Controller Interface (MGCI), and a corresponding protocol, Media Gateway Control Protocol (MGCP), for controlling voice-over-IP (VoIP) embedded clients from external call control elements. The MGCP assumes a call control architecture where the call control “intelligence“ is outside the gateways an
23、d is handled by external call control elements. The profile, as described in this Recommendation, will be referred to as the Network-based Call Signalling (NCS) Protocol. This Recommendation is based on the Media Gateway Control Protocol (MGCP) 1.0 RFC 2705, which is the result of a merge of the Sim
24、ple Gateway Control Protocol, and the IP Device Control (IPDC) family of protocols. This Recommendation is technically compatible with the corresponding CableLabs PacketCable specification. 2 References 2.1 Normative references The following ITU-T Recommendations and other references contain provisi
25、ons which, through reference in this text, constitute provisions of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; users of this Recommendation are therefore encouraged to investigate the possibili
26、ty of applying the most recent edition of the Recommendations and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendat
27、ion. ITU-T Recommendation G.168 (2004), Digital network echo cancellers. ITU-T Recommendation J.83 (1997), Digital multi-programme systems for television, sound and data services for cable distribution. ITU-T Recommendation J.112 Annex A (2001), Digital Video Broadcasting: DVB interaction channel fo
28、r Cable TV (CATV) distribution systems. ITU-T Recommendation J.112 Annex B (2004), Data-over-cable service interface specifications: Radio-frequency interface specification. ITU-T Recommendation J.160 (2005), Architectural framework for the delivery of time-critical services over cable television ne
29、tworks using cable modems. ITU-T Recommendation J.161 (2001), Audio codec requirements for the provision of bidirectional audio service over cable television networks using cable modems. ITU-T Recommendation J.163 (2005), Dynamic quality of service for the provision of real-time services over cable
30、television networks using cable modems. ITU-T Recommendation V.8 (2000), Procedures for starting sessions of data transmission over the public switched telephone network. 2 ITU-T Rec. J.162 (11/2005) ITU-T Recommendation V.25 (1996), Automatic answering equipment and general procedures for automatic
31、 calling equipment on the general switched telephone network including procedures for disabling of echo control devices for both manually and automatically established calls. IETF RFC 821 (1982), Simple Mail Transfer Protocol. IETF RFC 1034 (1987), Domain names Concepts and facilities. IETF RFC 2045
32、 (1996), Multipurpose Internet Mail Extensions (MIME) Part One: Format of Internet Message Bodies. IETF RFC 2234 (1997), Augmented BNF for Syntax Specifications: ABNF. IETF RFC 2327 (1998), SDP: Session Description Protocol. IETF RFC 2543 (1999), SIP: Session Initiation Protocol. IETF RFC 3550 (2003
33、), RTP: A Transport Protocol for Real-Time Applications. 2.2 Informative references ITU-T Recommendation H.323 (2003), Packet-based multimedia communications systems. CableLabs PKT-SP-EC-MGCP-I08-030728, PacketCable Network-Based Call Signaling Protocol Specification. IETF RFC 3551 (2003), RTP Profi
34、le for Audio and Video Conferences with Minimal Control. IETF RFC 2705 (1999), Media Gateway Control Protocol (MGCP) Version 1.0. ETSI ETS 300 001 ed. 4 (1997-01), Attachments to the Public Switched Telephone Network (PSTN); General technical requirements for equipment connected to an analogue subsc
35、riber interface in the PSTN. ETSI EN 300 659-1 V1.3.1 (2001-01), Access and Terminals (AT); Analogue access to the Public Switched Telephone Network (PSTN); Subscriber line protocol over the local loop for display (and related) services; Part 1: On-hook data transmission. ETSI EN 300 659-3 V1.3.1 (2
36、001-01), Access and Terminals (AT); Analogue access to the Public Switched Telephone Network (PSTN); Subscriber line protocol over the local loop for display (and related) services; Part 3: Data link message and parameter codings. ETSI ETS 300 324-1 ed. 1 (1994-02), V interfaces at the digital Local
37、 Exchange (LE); V5.1 interface for the support of Access Network (AN); Part 1: V5.1 interface specification. ETSI ETS 300 347-1 ed. 1 (1994-09), V interfaces at the digital Local Exchange (LE); V5.2 interface for the support of Access Network (AN); Part 1: V5.2 interface specification. ETSI ETS 300
38、166 ed. 1 (1993-08), Transmission and Multiplexing (TM); Physical and electrical characteristics of hierarchical digital interfaces for equipment using the 2048 kbit/s-based plesiochronous or synchronous digital hierarchies. ETSI ETS 300 167 ed. 1 (1993-08), Transmission and Multiplexing (TM); Funct
39、ional characteristics of 2048 kbit/s interfaces. ITU-T Rec. J.162 (11/2005) 3 3 Terms, definitions and abbreviations 3.1 Terms and definitions This Recommendation defines the following terms: 3.1.1 cable modem: A cable modem is a layer two termination device that terminates the customer end of the J
40、.112 connection. 3.1.2 IPCablecom: An ITU-T project that includes an architecture and a series of Recommendations that enable the delivery of time-critical interactive services over cable television networks. 3.2 Abbreviations This Recommendation uses the following abbreviations: API Application Pro
41、gramming Interface CPE Customer Premise Equipment DTMF Dual Tone Multi Frequency IP Internet Protocol MGCI Media Gateway Controller Interface MGCP Media Gateway Control Protocol MIB Management Information Base MTA Media Terminal Adapter MWD Maximum Waiting Delay NCS Network Call Signalling PSTN Publ
42、ic Switched Telephone Network RTP Real-time Protocol SDP Session Description Protocol UDP User Datagram Protocol 4 Conventions Throughout this Recommendation, the words that are used to define the significance of particular requirements are capitalized. These words are: “MUST“ This word or the adjec
43、tive “REQUIRED“ means that the item is an absolute requirement of this Recommendation. “MUST NOT“ This phrase means that the item is an absolute prohibition of this Recommendation. “SHOULD“ This word or the adjective “RECOMMENDED“ means that there may exist valid reasons in particular circumstances
44、to ignore this item, but the full implications should be understood and the case carefully weighed before choosing a different course. “SHOULD NOT“ This phrase means that there may exist valid reasons in particular circumstances when the listed behaviour is acceptable, or even useful, but the full i
45、mplications should be understood and the case carefully weighed before implementing any behaviour described with this label. 4 ITU-T Rec. J.162 (11/2005) “MAY“ This word or the adjective “OPTIONAL“ means that this item is truly optional. One vendor may choose to include the item because a particular
46、 marketplace requires it or because it enhances the product, for example; another vendor may omit the same item. 5 Introduction This Recommendation describes the NCS profile of an application programming interface (MGCI) and a corresponding protocol (MGCP) for controlling embedded clients from exter
47、nal call control elements. An embedded client is a network element that provides: two or more traditional analogue access lines to a voice-over-IP (VoIP) network; optionally, one or more video lines to a VoIP network. Embedded clients may not be confined to residential use only. For example, they ma
48、y be used in a business as well. Embedded clients are used for line-side access and, as such, are expected to have line-side equipment, e.g., analogue access lines for conventional telephones associated with them, as opposed to trunk gateways. The MGCP assumes a call control architecture where the c
49、all control “intelligence“ is outside the gateways and handled by external call-control elements referred to as Call Agents. The MGCP assumes that these call-control elements, or Call Agents (CAs), will synchronize with each other to send coherent commands to the gateways under their control. The MGCP defined in this Recommendation does not define a mechanism for synchronizing Call Agents, although future IPCablecom specifications may specify such mechanisms. The MGCP assumes a connection model where the b