1、INTERNATIONAL TELECOMMUNICATION UNION ITU-T TELECOMMUNICATION STAN DARD IZATION SECTOR OF ITU V.92 Amendment 2 (0312002) SERIES V: DATA COMMUNICATION OVER THE TELEPHONE NETWORK Simultaneous transmission of data and other signals Enhancements to Recommendation V.90 Amendment 2 ITU-T Recommendation V.
2、92 (2000) - Amendment 2 ITU-T V-SERIES RECOMMENDATIONS DATA COMMUNICATION OVER THE TELEPHONE NETWORK General Interfaces and voiceband modems Wideband modems Error control Transmission quality and maintenance Simultaneous transmission of data and other signals interworking with other networks Interfa
3、ce layer specifications for data communication Control procedures Modems on digital circuits V.l-V.9 V. 10-V.34 v.35-v.39 v.40-v.49 V.50-V.59 V.6Q-V.99 V. 100-V. 199 V.200-V.249 V.250-V.299 V.300-V.399 For further details, please refer to the list of ITU-T Recommendations ITU-T Recommendation V.92 E
4、nhancements to Recommendation V.90 Amendment 2 Summary This amendment enhances the original V.90 Recommendation by adding interaction facilities for error-correcting procedures. Source Amendment 2 to ITU-T Recommendation V.92 (2000) was prepared by ITU-T Study Group 16 (2001-2004) and approved under
5、 the WTSA Resolution 1 procedure on 29 March 2002. ITU-T Rec. V.92 (2000)/Amd.2 (03/2002) 1 FOREWORD The International Telecommunication Union (IT) is the United Nations specialized agency in the field of telecommunications. The ITU Telecommunication Standardization Sector (ITU-T) is a permanent org
6、an of ITU. IT-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, establishes the t
7、opics for study by the IT-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 standards are pr
8、epared 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 ITU draws attention to the possibility that the p
9、ractice 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 Intellectual Property Rights, whether asserted by IT members or others outside of the Recommendation deve
10、lopment 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. However, implementors are cautioned that this may not represent the latest information and are therefore
11、 strongly urged to consult the TSB patent database. o ITU 2002 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. 11 ITU-T Rec. V.92 (2000)/Amd.2 (03/2002) ITU-T Recommendation V.92 Enhancements to Recommendation
12、V.90 Amendment 2 1) New clause 9.10.3 Add the following new clause to the Recommendation: 9.10.3 Interaction with error-correcting procedures When entering the on-hold state, error-correcting procedures such as ITU-T Rec. V.42 shall be suspended, for example, by freezing the acknowledgement timers.
13、When returning to data mode following a modem-on-hold session, the error-correcting procedures shall be resumed, for example by un-freezing the V.42 acknowledgement timers. It shall not be re- established as a new call, re-exchanging XID frames, nor use link re-establishment procedures. Even though
14、the originator and answerer roles might be reversed, ITU-T Rec. V.42 shall still use the same CommandResponse bits from the initial connection. ITU-T Rec. V.92 (2000)lAmd.2 (0312002) 1 SERIES OF ITU-T RECOMMENDATIONS Series A Series B Series C Series D Series E Series F Series G Series H Series I Se
15、ries J Series K Series L Series M Series N Series O Series P Series Q Series R Series S Series T Series U Series V Series X Series Y Series Z Organization of the work of IT-T Means of expression: definitions, symbols, classification General telecommunication statistics General tariff principles Over
16、all network operation, telephone service, service operation and human factors Non-telephone telecommunication services Transmission systems and media, digital systems and networks Audiovisual and multimedia systems Integrated services digital network Cable networks and transmission of television, so
17、und programme and other multimedia signals Protection against interference Construction, installation and protection of cables and other elements of outside plant TMN and network maintenance: international transmission systems, telephone circuits, telegraphy, facsimile and leased circuits Maintenanc
18、e: international sound programme and television transmission circuits Specifications of measuring equipment Telephone transmission quality, telephone installations, local line networks Switching and signalling Telegraph transmission Telegraph services terminal equipment Terminals for telematic services Telegraph switching Data communication over the telephone network Data networks and open system communications Global information infrastructure and Internet protocol aspects Languages and general software aspects for telecommunication systems Printed in Switzerland Geneva, 2002
