ITU-T V 152-2010 Procedures for supporting voice-band data over IP networks (Study Group 16)《用于辅助IP网中音频数据的规程 16号研究组》.pdf

1、 International Telecommunication Union ITU-T V.152TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (09/2010) SERIES V: DATA COMMUNICATION OVER THE TELEPHONE NETWORK Interworking with other networks Procedures for supporting voice-band data over IP networks Recommendation ITU-T V.152 ITU-T V-SERIES RE

2、COMMENDATIONS DATA COMMUNICATION OVER THE TELEPHONE NETWORK General V.1V.9 Interfaces and voiceband modems V.10V.34 Wideband modems V.35V.39 Error control V.40V.49 Transmission quality and maintenance V.50V.59 Simultaneous transmission of data and other signals V.60V.99 Interworking with other netwo

3、rks V.100V.199Interface layer specifications for data communication V.200V.249 Control procedures V.250V.299 Modems on digital circuits V.300V.399 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T V.152 (09/2010) i Recommendation ITU-T V.152 Procedures for supporting

4、 voice-band data over IP networks Summary Voice-band data traffic has traditionally been transported by circuit switched systems and equipment. With the advent of the networks optimized for the transport of Internet Protocol (IP), and as a result of its considerable growth and pervasive nature, more

5、 and more voice-band data traffic is expected to be carried over IP networks. Given that voice and voice-band data services remain a significant part of telecommunications, there is a need to ensure a high quality of service for voice and voice-band data carried in part, or wholly, via IP. Recommend

6、ation ITU-T V.152 defines procedures for equipment that interconnect GSTN networks with IP networks to provide satisfactory, transparent delivery of modulated voice-band data (VBD) as encoded audio content over IP (data modems, facsimile terminals and text telephones). Annex B defines a method that

7、uses data signal detection and silence insertion in voiceband data that adds a means of providing bandwidth savings during transmission. Annex C addresses a problem discovered during the implementation of ITU-T V.152 gateways with the transmission of facsimile terminals. While this issue has been re

8、solved by an amendment to Recommendation ITU-T T.30, due to the extremely large numbers of terminals deployed in the field and the low probability that they would be corrected retroactively, it was considered pre-emptive to include a solution in an ITU-T V.152 media gateway. This Recommendation is c

9、omplementary to the modem relay and voice-band data Recommendations (Recommendations ITU-T V.150.0 and V.150.1). This revision includes the updating of references, general editing improvements for clarity and many additional examples of call control. It also integrates changes introduced by Corrigen

10、dum 1 (2005) for clarification to clauses 7.1 and 7.1.1; by Corrigendum 2 (2006) for clarifications on the use and control of echo cancellers and the application of IETF RFC 2833 with VBD; and by Amendment 1 (2009) for new Annexes B and C. History Edition Recommendation Approval Study Group 1.0 ITU-

11、T V.152 2005-01-08 16 1.1 ITU-T V.152 (2005) Cor. 1 2005-09-13 16 1.2 ITU-T V.152 (2005) Cor. 2 2006-05-29 16 1.3 ITU-T V.152 (2005) Amend. 1 2009-03-16 16 2.0 ITU-T V.152 2010-09-13 16 Keywords Echo canceller, facsimile over IP, gateway, Internet gateway, Internet Protocol, IP gateway, media gatewa

12、y, media gateway controller, modem over IP, quality of service, speech coding, TDM, TDM-IP gateway, text over IP, textphone over IP, text telephone, VBD, voice-band data, voice gateway, voice over IP, VoIP. ii Rec. ITU-T V.152 (09/2010) FOREWORD The International Telecommunication Union (ITU) is the

13、 United 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 Reco

14、mmendations 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

15、 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, the expression “Admini

16、stration“ 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 com

17、pliance 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

18、 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 claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed

19、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 received notice of intellectual property, protected by patents, which may be required to implement this Recommendation

20、. 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 2011 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without

21、the prior written permission of ITU. Rec. ITU-T V.152 (09/2010) iii Table of Contents Page 1 Scope 1 2 References. 1 3 Definitions 3 3.1 Terms defined elsewhere 3 3.2 Terms defined in this Recommendation . 3 4 Abbreviations and acronyms 4 5 Conventions 5 5.1 Recommendation version . 5 5.2 SDP Offer/

22、Answer protocol variants 5 6 Definition of the VBD mode of operation 6 6.1 Minimum requirements for VBD mode of operation . 6 6.2 Echo canceller and VBD mode 6 6.3 IP transport services for VBD 7 7 Negotiation of support of VBD and selection of VBD codec and other VBD enhanced functionality 7 7.1 Ne

23、gotiation using the session description protocol 8 7.2 Use of VBD in ITU-T H.323 systems 32 7.3 Mid-call negotiation using session description protocol 34 8 The use of IETF RFC 4733 modem/facsimile/text telephone events . 35 9 VBD stimuli 36 10 Procedures for transitioning between audio mode and VBD

24、 mode . 36 10.1 Procedures for state transitioning . 37 10.2 State machine Overview 39 10.3 Enforced state transition by call/session control 39 11 Optional procedures for indicating to a remote end transition into VBD using state signalling events . 39 11.1 Declaration of SSEs 39 11.2 Transition to

25、 the VBD mode for ITU-T V.150.1 gateways . 39 11.3 Transition to the VBD mode for non- ITU-T V.150 cases . 40 11.4 Transition from the VBD media mode . 41 11.5 Security Optional . 43 Annex A Vendor-defined messages 44 Annex B Use of data signal detection and silence insertion in voiceband data 45 B.

26、1 Introduction 45 B.2 Guideline for the use of DSD . 45 B.3 Negotiation of the DSD capability with SDP . 45 B.4 Negotiation of the DSD capability with ITU-T H.245 46 iv Rec. ITU-T V.152 (09/2010) Page Annex C Use of ITU-T V.21 preamble for echo canceller control in an ITU-T V.152 gateway . 47 Biblio

27、graphy. 49 Rec. ITU-T V.152 (09/2010) 1 Recommendation ITU-T V.152 Procedures for supporting voice-band data over IP networks 1 Scope This Recommendation describes the voice-band data (VBD) operation of Voice-over-Internet Protocol (VoIP) gateways and media gateways. The term “VBD“ refers only to th

28、e use of suitable voice-band codecs for the transport of data payloads via RTP. The VBD procedures described in this Recommendation shall apply to VBD-only capable gateways. An ITU-T V.152 gateway only has the guarantee of interworking with another gateway if that gateway also supports ITU-T V.152.

29、This does not preclude the interworking with non-ITU-T V.152 gateways; however, there are no guarantees of performance and supported functionality with such systems. The negotiation of a VBD capability does not exclude from a VoIP session any other capabilities such as the transport of audio signals

30、, RFC 4733-based telephone events, ITU-T T.38 facsimile relay, RFC 4103 text relay and ITU-T V.150.1 modem relay, etc. Declaration of VBD support using the session description protocol (SDP) is detailed in clause 7.1. Declaration of VBD support using ITU-T H.245 is detailed in clause 7.2. This Recom

31、mendation supports hybrid modes of operation; for example, a device may support a VBD and facsimile relay capability but not a modem relay or text relay capability. In this example of hybrid operation modem and text payloads are transported in the VBD mode, while facsimile payloads could be transpor

32、ted in the ITU-T T.38 facsimile relay mode or in the VBD mode. The negotiation of such hybrid sets of capabilities follows SDP and ITU-T H.245 mechanisms (clause 11). This Recommendation describes the default mechanism for transitioning into VBD mode via payload-type switching as described in clause

33、 10 and the optional mechanism of utilizing the state signalling events (SSE) messages described in clause 11. 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

34、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 possibility of applying the most recent edition of the Recommendations and other references listed below. A list

35、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 Recommendation. ITU-T G.168 Recommendation ITU-T G.168 (2004), Digital network echo cancellers. ITU-T G.701 Recomme

36、ndation ITU-T G.701 (1993), Vocabulary of digital transmission and multiplexing, and pulse code modulation (PCM) terms. ITU-T G.711 Recommendation ITU-T G.711 (1988), Pulse code modulation (PCM) of voice frequencies. ITU-T G.726 Recommendation ITU-T G.726 (1990), 40, 32, 24, 16 kbit/s Adaptive Diffe

37、rential Pulse Code Modulation (ADPCM). ITU-T G.728 Recommendation ITU-T G.728 (1992), Coding of speech at 16 kbit/s using low-delay code excited linear prediction. 2 Rec. ITU-T V.152 (09/2010) ITU-T G.729 Recommendation ITU-T G.729 (1996), Coding of speech at 8 kbit/s using conjugate-structure algeb

38、raic-code-excited linear prediction (CS-ACELP). ITU-T H.245 Recommendation ITU-T H.245 (2005), Control protocol for multimedia communication. ITU-T H.248.1 Recommendation ITU-T H.248.1v3 (2005), Gateway control protocol: Version 3. ITU-T H.248.2 Recommendation ITU-T H.248.2 (2005), Gateway control p

39、rotocol: Facsimile, text conversation and call discrimination packages, plus Amendment 1 (2007), Discriminated call type enhancement. ITU-T H.248.39 Recommendation ITU-T H.248.39 (2006), Gateway control protocol: H.248 SDP parameter identification and wildcarding. ITU-T H.323 Recommendation ITU-T H.

40、323 (2003), Packet-based multimedia communications systems. ITU-T T.30 Recommendation ITU-T T.30 (2005), Procedure for document facsimile transmission in the general switched telephone network. ITU-T T.35 Recommendation ITU-T T.35 (2000), Procedure for the allocation of ITU-T defined codes for non-s

41、tandard facilities. ITU-T T.38 Recommendation ITU-T T.38 (2004), Procedures for real-time Group 3 facsimile communication over IP networks. ITU-T T.120 Recommendation ITU-T T.120 (1996), Data protocols for multimedia conferencing. ITU-T V.8 Recommendation ITU-T V.8 (2000), Procedures for starting se

42、ssions of data transmission over the public switched telephone network. ITU-T V.18 Recommendation ITU-T V.18 (2000), Operational and interworking requirements for DCEs operating in the text telephone mode. ITU-T V.21 Recommendation ITU-T V.21 (1988), 300 bits per second duplex modem standardized for

43、 use in the general switched telephone network. ITU-T V.34 Recommendation ITU-T V.34 (1998), A modem operating at data signalling rates of up to 33 600 bit/s for use on the general switched telephone network and on leased point-to-point 2-wire telephone-type circuits. ITU-T V.150.1 Recommendation IT

44、U-T V.150.1 (2003), Modem-over-IP networks: Procedures for the end-to-end connection of V-series DCEs. IETF RFC 768 IETF RFC 768 (1980), User Datagram Protocol. IETF RFC 791 IETF RFC 791 (1981), Internet Protocol DARPA Internet Program Protocol Specification. IETF RFC 2198 IETF RFC 2198 (1997), RTP

45、Payload for Redundant Audio Data. IETF RFC 3261 IETF RFC 3261 (2002), SIP: Session Initiation Protocol. IETF RFC 3264 IETF RFC 3264 (2002), An Offer/Answer Model with the Session Description Protocol (SDP). IETF RFC 3388 IETF RFC 3388 (2002), Grouping of Media Lines in the Session Description Protoc

46、ol (SDP). IETF RFC 3389 IETF RFC 3389 (2002), Real-time Transport Protocol (RTP) Payload for Comfort Noise (CN). Rec. ITU-T V.152 (09/2010) 3 IETF RFC 3550 IETF RFC 3550 (2003), RTP: A Transport Protocol for Real-Time Applications. IETF RFC 4103 IETF RFC 4103 (2005), RTP Payload for Text Conversatio

47、n. IETF RFC 4566 IETF RFC 4566 (2006), SDP: Session Description Protocol. IETF RFC 4733 IETF RFC 4733 (2006), RTP Payload for DTMF Digits, Telephony Tones and Telephony Signals. IETF RFC 4756 IETF RFC 4756 (2006), Forward Error Correction Grouping Semantics in Session Description Protocol. IETF RFC

48、5109 IETF RFC 5109 (2007), RTP Payload Format for Generic Forward Error Correction. 3 Definitions 3.1 Terms defined elsewhere This Recommendation uses the terms defined in ITU-T G.701. 3.2 Terms defined in this Recommendation This Recommendation defines the following terms: 3.2.1 audio mode: In this

49、 mode, the channel processes speech signals. The mode may include the use of compression algorithms and other processing functions that are not suitable for the transport of modem or facsimile signals. 3.2.2 general switched telephone network (GSTN): This network includes ATM, PSTN, ISDN, wireless networks and private networks. 3.2.3 ITU-T H.248 gateway: A media gateway that complies with the ITU-T H.248x series of Recommendations. 3.2.4 media gateway (MG): The media gateway conve