1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOM M U N I CATION STANDARDIZATION SECTOR OF ITU T.39 (I 0/97) SERIES T: TERMINALS FOR TELEMATIC SERVICES Application profiles for simultaneous voice and facsimile terminals ITU-T Recommendation T.39 (Previously CCITT Recommendation) STD-ITU-T RECMN Ta
2、39-ENGL 1997 4862593 0645364 369 W ITU-T T-SERIES RECOMMENDATIONS TERMINALS FOR TELEMATIC SERVICES For further details, please refer to ITU-T List of Recommendations. . STD.ITU-T RECMN TmICI-ENGL 3997 m 4862593 Ob453b5 2T5 ITU-T RECOMMENDATION T.39 APPLICATION PROFILES FOR SIMULTANEOUS VOICE AND FAC
3、SIMILE TERMINALS Summary This Recommendation defines the procedures to be applied to allow Group 3 facsimile transmission simultaneously with at least speech and audio communication over the GSTN by making use of the capabilities of recommendations describing analogue or digital simultaneous voice a
4、nd data transmission (Recommendations V.61, V.70 and H.324). These procedures will allow: 0 0 The use of simultaneous voice and fax capability is an option of Group 3 facsimile communication. initiation of a facsimile call and enabling simultaneous speech communication during the call; initiation of
5、 a voice call and enabling simultaneous facsimile transmission during the call; initiation of a multimedia call and enabling simultaneous facsimile transmission during the call. Source IT-T Recommendation T.39 was prepared by ITU-T Study Group 8 (1997-2000) and was approved under the WTSC Resolution
6、 No. 1 procedure on the 16th of October 1997. Recommendation T.39 (10/97) i FOREWORD ITU (International Telecommunication Union) is the United Nations Specialized Agency in the field of telecommuni- cations. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of the IT. The
7、 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 Conference (WTSC), which meets every four years, establishes the topics f
8、or study by the ITU-T Study Groups which, in their turn, produce Recommendations on these topics. The approval of Recommendations by the Members of the IT-T is covered by the procedure laid down in WTSC Resolution No. 1. In some areas of information technology which fall within ITU-Ts purview, the n
9、ecessary standards are prepared on a collaborative basis with IS0 and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized operating agency. INTELLECTUAL PROPERTY RIGHTS The ITU draws attention
10、to the possibility that the practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. The IT takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others o
11、utside of the Recommendation development process. As of the date of approval of this Recommendation, the ITU had 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
12、 latest information and are therefore strongly urged to consult the TSB patent database. O ITU 1998 All rights reserved. No part of this publication may be reproduced or utilized in any form .or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writi
13、ng from the IT. 11 Recommendation T.39 (10/97) STD.ITU-T RECMN T.39-ENGL 3997 4862593 0645367 078 CONTENTS 1 Scope 2 References 2.1 Normative references . 2.2 Informative references 3 Abbreviations . 4 Introduction Simultaneous voice and facsimile modulation schemes . Overview of the V.61-based simu
14、ltaneous voice and facsimile scheme (ASVF) Overview of the V.70-based simultaneous voice and facsimile scheme (DSVF) Overview of the H.324-based simultaneous voice and facsimile scheme (MSVF) 4.1 4.2 4.3 4.4 5 Operational modes . Initiation as SVF call Switch to voice only during SVF call . Switch t
15、o voice only during SVF call . SVF terminal to standard facsimile terminal 5.5 Voice only call Facsimile operation during SVF 6.1 Indications for Recommendation T.30 . 6.2 Indications for Annex FT.90 . 6.3 Indications for Recommendation V.76 . . 6.5 . 5.1 5.2 5.3 5.4 6 6.4 Operation on H.324 Indicat
16、ions for V.8 bis Recommendation T.39 (10/97) Page 1 1 1 2 2 3 3 3 3 4 4 5 5 10 10 10 10 10 10 11 12 12 . 111 STD-ITU-T RECMN T.39-ENGL 1997 m 4862591 0645368 TO4 m Recommendation T.39 APPLICATION PROFILES FOR SIMULTANEOUS VOICE AND FACSIMILE TERMINALS (Geneva, 199 7) 1 Scope This Recommendation defi
17、nes the procedures to be applied to allow Group 3 facsimile transmission simultaneously with at least speech and audio communication over the GSTN by making use of the capabilities of recommendations describing analogue or digital simultaneous voice and data transmission (Recommendations V.6 1, V.70
18、 and H.324). These procedures will allow: initiation of a facsimile call and enabling simultaneous speech communication during the call; initiation of a voice call and enabling simultaneous facsimile transmission during the call; initiation of a multimedia call and enabling simultaneous facsimile tr
19、ansmission during the call. The use of simultaneous voice and fax capability is an option of Group 3 facsimile communication. 2 References 2.1 Normative references The following ITLJ-T Recommendations and other references contain provisions which, through reference in this text, constitute provision
20、s of this Recommendation. At the time of publication, the editions indicated were valid. All Recommendations and other references are subject to revision; all users of this Recommendation are therefore encouraged to investigate the possibility of applying the most recent editions of the Recommendati
21、ons and other references listed below. A list of the currently valid ITU-T Recommendations is regularly published. ITU-T Recommendation G.723.1 (1996), Speech coders: Dual rate speech coder for multimedia communications transmitting at 5.3 and 6.3 kbits. ITU-T Recommendation H.223 (1 996), Multiplex
22、ingprotocol for low bit rate multimedia Communication. ITU-T Recommendation H.324 (1996), Terminal for low bit rate multimedia communication. ITU-T Recommendation H.245 ( 1997), Control protocol for multimedia communicaion. ITU-T Recommendation T.4 ( 1996), Standardization of Group 3 facsimile termi
23、nals for document transmission. ITU-T Recommendation T.30 (l996), Procedures for document facsimile transmission in the general switched telephone network. ITU-T Recommendation T.66 (1997), Facsimile code points for use with Recornmendation F 8 bis. CCITT Recommendation T.90 (1992), Characteristics
24、and protocols for terminals for telematic services in ISDN. ITU-T Recommendation V.8 (1994), Procedures for starting sessions of data transmission over the general switched telephone network. ITU-T Recommendation V.8 bis (1996), Procedures for the identijcation und selection of common modes of opera
25、tion between data circuit-terminating equipments (DCEs) and between Data Terminal Equipments (DTEs) over the general switched telephone network and on leasedpoint-to-point telephone-type circuits. IT-T Recommendation V.34 (1996), A modem operating at data signalling rates of up to 33 600 bids for us
26、e on the general switched telephone network und on leasedpoint-to-point 2-wire telephone-ppe circuits. Recommendation T.39 (10197) 1 - ITU-T Recommendation V.61 (1996), A simultaneous voice plus data modem, operating at a voice plus data signalling rate of 4800 bids, with optional automatic switchin
27、g to data-only signalling rates of up to I4 400 bit/s for use on the general switched telephone network and on leusedpoint-to-point 2-wire telephone ype circuits. - ITU-T Recommendation V.70 (1996), Procedures for the simultaneous transmission of data and digitally encoded voice signals over the GSm
28、, or over a 2-wire leasedpoint-to-point telephone tpe circuit. - IT-T Recommendation V.15 (1996), DSVD terminal controlprocedures. - IT-T Recommendation V.76 (1996), Generic multiplexer using V.42 LAPM-busedprocedures. 2.2 Informative references - ITU-T Recommendation V.25 ter (1997), Serial asynchr
29、onous automatic dialling and control. 3 Abbreviations This Recommendation uses the following abbreviations: AL-SDU ANS ANSam ASVD ASVF CCITT CRC DCE DCN DSVD DSVF DTE GSTN HDLC IS0 ITU-T LAPM LCN MSVF SE SVF UNERM 2 Adaptation Layer Service Data Unit (see Recommendation H.223) V.25 answer tone V.8 m
30、odulated answer tone Analogue Simultaneous Voice and Data communication Analogue Simultaneous Voice and Facsimile communication Intemational Telegraph and Telephone Consultative Committee Cyclic Redundancy Check Data Communication Equipment Facsimile disconnect signal Digital Simultaneous Voice and
31、Data communication Digital Simultaneous Voice and Facsimile communication Data Terminal Equipment General Switched Telephone Network High-level Data Link Control, per ISOAEC 3309 International Organization for Standardization International Telecommunication Union - Telecommunication Standardization
32、Sector (former CCITT) Link Access Procedures for Modems (per Recommendation V.42) Logical Channel Number (per Recommendation H.223) Multimedia Simultaneous Voice and Facsimile communication Session Exchange (per Recommendation H.233) Simultaneous Voice and Facsimile communication Unacknowledged Non-
33、Error Recovery Mode Recommendation T.39 (10/97) 4 Introduction 4.1 Simultaneous voice and facsimile modulation schemes Several schemes may be employed to provide simultaneous voice and facsimile transmission over the GSTN. These schemes all make use of modulation techniques for voice and data transm
34、ission defined by the V-Series Recommenda- tions. Three Application Profiles are defined in this Recommendation. These are: 0 ASVF, based on the V.61 scheme, which is an analogue simultaneous voice and data (ASVD) scheme; DSVF, based on V.70, which is a digital simultaneous voice and data (DSVD) sch
35、eme; and MSVF, based on the H.324 scheme, which is a multimedia terminal based scheme. Wherever the term “voice“ is used, it applies to the transmission of speech and other audio information such as may occur during voice transmission over the GSTN. In SVF operation, the terms “calling“ and “caHled“
36、 terminals do not necessarily correspond to actions in initiating and responding to SVF operation. This is especially true when SVF operation is initiated after a voice call has been established. NOTE - One other simultaneous voice and data scheme is under study in Recommendation V.34 (draft Recomme
37、ndation V.34Q). This may be included in future extensions of this Recommendation. It is expected to use similar Application Profiles to the V.61, V.70, or H.324-based profile depending on whether they are ASVD, DSVD, or H.324 based. 4.2 Overview of the V.61-based simultaneous voice. and facsimile sc
38、heme (ASVF) The V.6 1 -based simultaneous voice and facsimile (ASVF) operation utilizes the modulation scheme standardized in Recommendation V.61 - A simultaneous voice plus data modem, operating at a voice and data signalling rate of 4800 bits, with optional automatic switching to data-only signall
39、ing rates of up to 14.4 kbit/s. The V.61 modulation scheme provides data only communication at rates up to 14.4 kbit/s, and data communication during voice operation in the direction of voice at a minimum rate of 4.8 kbits with automatic rate changes up to 14.4 kbits during silence. In the voice and
40、 data mode V.61 provides two full duplex virtual channels, one of which is used for voice communication; the other for any type of data, including facsimile. This Application Profile describes how the data channel of a V.61 ASVD device may be used for facsimile transmission (ASVF) at the same rates
41、as the defined data operations. The facsimile transmission method used is that described in Annex UT.30, analogue mode (G3V). The use of V.8 bis is inherent in the ASVD procedure. Facsimile terminals based on this application profile will be able to perform all standard Group 3 functions as well as
42、any selected optional functions when connected to any other Group 3 terminal. The ASVF functionality is only available when the initial V.8 bis procedures identi the called terminal as possessing the same ASVF capabilities as those of the initiating terminal. The particular SVF mode chosen depends o
43、n the capabilities identified during the V.8 bis procedures. The SVF operation is only invoked upon request by the initiating or responding terminal, either at the initiation of or during the call. Likewise, SVF operation may be terminated at any time during the call. 4.3 Overview of the V.70-based
44、simultaneous voice and facsimile scheme SVF) The V.70-based simultaneous voice and facsimile (DSVF) operation utilizes the methods standardized in Recommendation V.70. This scheme provides one or more voice channels and one or more data channels multiplexed together and transmitted via a V.32 bis or
45、 V.34 modem. This Application Profile for simultaneous voice and facsimile describes how the data channel of a DSVD device may be used for facsimile transmission at the same rates as the defined data operations. The facsimile transmission method used is that described in Annex CIT.30, analogue mode
46、(G3V). The use of V.8 bis is inherent in procedures based on Recommendation V.70. Recommendation T.39 (10/97) 3 Facsimile terminals based on this application profile will be able to perform all standard Group 3 functions as well as any selected optional functions when connected to any other Group 3
47、terminal. The DSVF functionality is only available when the initial V.8 bis procedures identifj the responding terminal as possessing the same DSVF capabilities as those of the initiating terminal. 4.4 Overview of the H.324-based simultaneous voice and facsimile scheme (MSVF) The H.324 -based simult
48、aneous voice and facsimile (MSVF) operation utilizes the methods standardized in the relevant H.324-Series of Recommendations, which include: The dual-mode 5.3/6.3 kbit/s Audio Codec (Recommendation G.723.1) encodes the audio signal from the microphone for transmission, and decodes the audio code wh
49、ich is output to the speaker. Other audio codecs of H.324 (e.g. G.729) are optional. The Control Protocol (H.245) provides end-to-end signalling for proper operation of the H.324 terminal, and signals all other end-to-end system functions including reversion to analogue speech-only telephony mode. It provides for capability exchange, signalling of commands and indications, and messages to open and fully describe the content of logical channels (such as of a dedicated T.30 facsimile channel). The Data Protocols (running over dedicated H.245 logical chan
