1、 INTERNATIONAL TELECOMMUNICATION UNION ITU-T J.171TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (02/2002) SERIES J: CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS IPCablecom IPCablecom Trunking Gateway Control Protocol (TGCP) ITU-T Recommendation J.171
2、ITU-T J-SERIES RECOMMENDATIONS CABLE NETWORKS AND TRANSMISSION OF TELEVISION, SOUND PROGRAMME AND OTHER MULTIMEDIA SIGNALS General Recommendations J.1J.9 General specifications for analogue sound-programme transmission J.10J.19 Performance characteristics of analogue sound-programme circuits J.20J.2
3、9 Equipment and lines used for analogue sound-programme circuits J.30J.39 Digital encoders for analogue sound-programme signals J.40J.49 Digital transmission of sound-programme signals J.50J.59 Circuits for analogue television transmission J.60J.69 Analogue television transmission over metallic line
4、s and interconnection with radio-relay links J.70J.79 Digital transmission of television signals J.80J.89 Ancillary digital services for television transmission J.90J.99 Operational requirements and methods for television transmission J.100J.109 Interactive systems for digital television distributio
5、n J.110J.129 Transport of MPEG-2 signals on packetised networks J.130J.139 Measurement of the quality of service J.140J.149 Digital television distribution through local subscriber networks J.150J.159 IPCablecom J.160J.179 Miscellaneous J.180J.199 Application for Interactive Digital Television J.200
6、J.209 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. J.171 (02/2002) i ITU-T Recommendation J.171 IPCablecom Trunking Gateway Control Protocol (TGCP) Summary This Recommendation describes IPCablecom profiles of an Application Programming Interface (API) and Trunk
7、Gateway Control Protocol (TGCP) for controlling voice-over-IP (VoIP) PSTN Media Gateways from external call control elements. Source ITU-T Recommendation J.171 was prepared by ITU-T Study Group 9 (2001-2004) and approved under the WTSA Resolution 1 procedure on 13 February 2002. ii ITU-T Rec. J.171
8、(02/2002) 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 a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff ques
9、tions 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, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendation
10、s 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 standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation,
11、the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that the practice or implementation of this Recommendation may involve the use of a claim
12、ed 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 no
13、t 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 2002 All rights re
14、served. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. J.171 (02/2002) iii CONTENTS Page 1 Scope 1 2 References 1 2.1 Normative references . 1 2.2 Informative. 1 3 Terms, definitions, abbreviations and conventions 2 3.1
15、 Definitions 2 3.2 Abbreviations . 2 3.3 Convention . 3 Annex A TGCP Profile 1 3 A.1 Scope 3 A.2 Media Gateway Control Interface (MGCI) 3 A.2.1 Model and naming conventions . 3 A.2.2 SDP use 9 A.2.3 Gateway control functions . 9 A.2.4 States, failover and race conditions 28 A.2.5 Return codes and er
16、ror codes . 38 A.2.6 Reason codes 40 A.3 Media Gateway Control Protocol. 40 A.3.1 General description 40 A.3.2 Command header 40 A.3.3 Response header formats 52 A.3.4 Session description encoding . 55 A.3.5 Transmission over UDP . 61 A.3.6 Piggybacking 62 A.3.7 Transaction identifiers and three-way
17、 handshake 63 A.3.8 Provisional responses . 64 A.4 Security. 65 Annex A.A Event packages 65 A.A.1 ISUP trunk package 66 Appendix A.I Mode interactions 69 Appendix A.II Example command encodings 70 A.II.1 NotificationRequest 70 A.II.2 Notify . 70 A.II.3 CreateConnection. 71 A.II.4 ModifyConnection .
18、72 iv ITU-T Rec. J.171 (02/2002) Page A.II.5 DeleteConnection (from the Media Gateway Controller) 73 A.II.6 DeleteConnection (from the trunking gateway). 73 A.II.7 DeleteConnection (multiple connections from the Media Gateway Controller) 73 A.II.8 AuditEndpoint 73 A.II.9 AuditConnection 74 A.II.10 R
19、estartInProgress . 75 Appendix A.III Example Call Flow 76 Appendix A.IV Endpoint requirements 79 A.IV.1 Connection modes supported . 79 Appendix A.V Compatibility information 79 A.V.1 NCS compatibility 79 A.V.2 MGCP compatibility 80 Appendix A.VI Example event packages. 81 A.VI.1 MF FGD Operator Ser
20、vices Package. 81 A.VI.2 MF Terminating Protocol Package 84 Appendix A.VII Bibliography 86 Annex A.B TGCP Profile 2 87 ITU-T Rec. J.171 (02/2002) 1 ITU-T Recommendation J.171 IPCablecom Trunking Gateway Control Protocol (TGCP) 1 Scope This Recommendation describes IPCablecom profiles of an Applicati
21、on Programming Interface (API) and Trunk Gateway Control Protocol (TGCP) for controlling voice-over-IP (VoIP) PSTN Media Gateways from external call control elements. Annexes to this Recommendation specify profiles for the above purpose. 2 References The following ITU-T Recommendations and other ref
22、erences contain provisions 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 in
23、vestigate the possibility 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. 2.1 Normative references ITU-T Recommendation J.161 (2001), Audio codec requirements for the provision o
24、f bidirectional audio service over cable television networks using cable modems. ITU-T Recommendation J.162 (2001), Network call signalling protocol for the delivery of time - critical services over cable television networks using data modems. ITU-T Recommendation J.170 (2002), IPCablecom security s
25、pecification. IETF RFC 2327 (1998), SDP: Session Description Protocol. NOTE The reference to a document within this Recommendation does not give it, as a stand-alone document, the status of a Recommendation. 2.2 Informative references IETF Internet Draft (draft-huitema-sgcp-v1-02.txt), Simple Gatewa
26、y Control Protocol (SGCP). IETF Internet Draft (draft-taylor-ipdc-00.txt), IPDC Base Protocol. IETF RFC 1889 (1996) RTP: A Transport Protocol for Real-Time Applications. IETF RFC 1890 (1996), RTP: Profile for Audio and Video Conferences with Minimal Control. IETF RFC 2543 (1999), SIP: Session Initia
27、tion Protocol. IETF RFC 2326 (1998) Real Time Streaming Protocol (RTSP). ITU-T Recommendation E.180/Q.35 (1998), Technical characteristics of tones for the telephone system. ITU-T Recommendation Q.761 (1999), Signalling System No. 7 ISDN User Part functional description. ITU-T Recommendation Q.762 (
28、1999), Signalling System No. 7 ISDN User Part general function of messasges and signals. ITU-T Recommendation H.323 (2000), Packet-based multimedia communications systems. 2 ITU-T Rec. J.171 (02/2002) ITU-T Recommendation H.225.0 (2000), Call signalling protocols and media stream packetization for p
29、acket-based multimedia communications systems. ITU-T Recommendation H.245 (2001), Control protocol for multimedia communication. IETF RFC 1825 (1995), Security Architecture for the Internet Protocol. IETF RFC 1826 (1995), IP Authentication Header. IETF RFC 2705 (1999), Media Gateway Control Protocol
30、 (MGCP) Version 1.0. TCP/IP Illustrated, Volume 1 (2001), The Protocols, Addison-Wesley, 1994. ITU-T Recommendation J.163 (2001), Dynamic quality of service for the provision of real time services over cable television networks using cable modems. 3 Terms, definitions, abbreviations and conventions
31、3.1 Definitions This Recommendation defines the following terms: 3.1.1 cable modem: The delivery of high-speed data access to customer locations using equipment built in conformance with ITU-T Recs. J.83 and J.112. 3.1.2 IPCablecom: An ITU-T project that includes an architecture and a series of Reco
32、mmendations that enable the delivery of real-time services over the cable television networks using cable modems. 3.2 Abbreviations This Recommendation uses the following abbreviations: DNS Domain Name System IP Internet Protocol IPSec Internet Protocol Security ISUP ISDN User Part MGC Media Gateway
33、 Controller MGCP Media Gateway Control Protocol MIB Management Information Base MTA Media Terminal Adapter MWD Maximum Waiting Delay NCS Network-based Call Signalling NTP Network Time Protocol QoS Quality of Service RTCP Real-Time Control Protocol RTO Retransmission Timeout RTP Real-Time Protocol SD
34、P Session Description Protocol SG Signalling Gateway SPI Security Parameters Index ITU-T Rec. J.171 (02/2002) 3 3.3 Convention If this Recommendation is implemented, the keywords “MUST“ and “SHALL“ as well as “REQUIRED“ are to be interpreted as indicating a mandatory aspect of this specification. Th
35、e key words indicating a certain level of significance of a particular requirements that are used throughout this Recommendation are summarized in below. “MUST“ This word or the adjective “REQUIRED“ means that the item is an absolute requirement of this specification. “MUST NOT“ This phrase means th
36、at the item is an absolute prohibition of this specification. “SHOULD“ This word or the adjective “RECOMMENDED“ means that there may exist valid reasons in particular circumstances to ignore this item, but the full implications should be understood and the case carefully weighed before choosing a di
37、fferent course. “SHOULD NOT“ This phrase means that there may exist valid reasons in particular circumstances when the listed behavior is acceptable or even useful, but the full implications should be understood and the case carefully weighed before implementing any behavior described with this labe
38、l. “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 marketplace requires it or because it enhances the product, for example; another vendor may omit the same item. Annex A TGCP Profile 1 A.1 Scope This
39、annex describes an IPCablecom profile of an Application Programming Interface (API) called a Media Gateway Control Interface (MGCI) and a corresponding protocol (MGCP) for controlling voice-over-IP (VoIP) PSTN gateways from external call control elements. The MGCP assumes a call control architecture
40、 where the call control “intelligence“ is outside the gateways and handled by external call control elements. The IPCablecom profile as described in this annex will be referred to as the IPCablecom Trunking Gateway Control Protocol (TGCP). This annex is based on the IPCablecom network-based call sig
41、nalling Recommendation (ITU-T Rec. J.162), and IETF RFC 2705, Media Gateway Control Protocol (MGCP). This annex, which defines the IPCablecom TGCP protocol, constitutes a specification that is independent of MGCP. The TGCP profile of MGCP is strictly and solely defined by the contents of this annex.
42、 NOTE The specification in this annex is used in North America. A.2 Media Gateway Control Interface (MGCI) MGCI functions provide for connection control, endpoint control, auditing, and status reporting. They each use the same system model and the same naming conventions. A.2.1 Model and naming conv
43、entions The MGCP assumes a connection model where the basic constructs are endpoints and connections. Connections are grouped in calls. One or more connections can belong to one call. Connections and calls are set up at the initiative of one or several MGCs. It should nonetheless be recognized that
44、in 4 ITU-T Rec. J.171 (02/2002) none of these cases is a “connection“ established within an IPCablecom network, as the term “connection“ is understood within the circuit-switched PSTN. The terms “call“ and “connection“ in this context (and throughout this Recommendation) are used for convenience of
45、reference, not to indicate any actual technical or other similarity between the IPCablecom network and the PSTN. A.2.1.1 Endpoint names Endpoint names, a.k.a. endpoint identifiers, have two components, both of which are defined to be case insensitive here: the domain name of the gateway managing the
46、 endpoint; a local endpoint name within that gateway. Endpoint names will be of the form: local-endpoint-namedomain-name where domain-name is an absolute domain-name as defined in IETF RFC 1034 and includes a host portion; thus, an example domain-name could be: MyTrunkingG Also, domain-name may be a
47、n IPv4 address in dotted decimal form represented as a text-string and surrounded by a left and a right square bracket (“ and “) as in “128.96.41.1“ please consult IETF RFC 821 for details. However, use of IP addresses is generally discouraged. Trunking gateways have one or more endpoints (e.g. one
48、for each trunk) associated with them, and each of the endpoints is identified by a separate local endpoint name. Just like the domain-name, the local endpoint name is case insensitive. Associated with the local endpoint name is an endpoint-type, which defines the type of the endpoint, e.g. DS-0, or
49、an analog access line. The type can be derived from the local endpoint name. The local endpoint name is a hierarchical name, where the least specific component of the name is the leftmost term, and the most specific component is the rightmost term. More formally, the local endpoint name must adhere to the following naming rules: The individual terms of the local endpoint name must be separated by a single slash (“/“, ASCII 2F hex). The individual terms a
