1、 International Telecommunication Union ITU-T H.321TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU Corrigendum 1(01/2005) SERIES H: AUDIOVISUAL AND MULTIMEDIA SYSTEMSInfrastructure of audiovisual services Systems and terminal equipment for audiovisual services Adaptation of H.320 visual telephone ter
2、minals to B-ISDN environments Corrigendum 1 ITU-T Recommendation H.321 (1998) Corrigendum 1 ITU-T H-SERIES RECOMMENDATIONS AUDIOVISUAL AND MULTIMEDIA SYSTEMS CHARACTERISTICS OF VISUAL TELEPHONE SYSTEMS H.100H.199 INFRASTRUCTURE OF AUDIOVISUAL SERVICES General H.200H.219 Transmission multiplexing and
3、 synchronization H.220H.229 Systems aspects H.230H.239 Communication procedures H.240H.259 Coding of moving video H.260H.279 Related systems aspects H.280H.299 Systems and terminal equipment for audiovisual services H.300H.349 Directory services architecture for audiovisual and multimedia services H
4、.350H.359 Quality of service architecture for audiovisual and multimedia services H.360H.369 Supplementary services for multimedia H.450H.499 MOBILITY AND COLLABORATION PROCEDURES Overview of Mobility and Collaboration, definitions, protocols and procedures H.500H.509 Mobility for H-Series multimedi
5、a systems and services H.510H.519 Mobile multimedia collaboration applications and services H.520H.529 Security for mobile multimedia systems and services H.530H.539 Security for mobile multimedia collaboration applications and services H.540H.549 Mobility interworking procedures H.550H.559Mobile mu
6、ltimedia collaboration inter-working procedures H.560H.569 BROADBAND AND TRIPLE-PLAY MULTIMEDIA SERVICES Broadband multimedia services over VDSL H.610H.619 For further details, please refer to the list of ITU-T Recommendations. ITU-T Rec. H.321 (1998)/Cor.1 (01/2005) i ITU-T Recommendation H.321 Ada
7、ptation of H.320 visual telephone terminals to B-ISDN environments Corrigendum 1 Summary The changes introduced by this corrigendum incorporate developments in the DSS2 signalling work (revised ITU-T Rec. Q.2931 and new ITU-T Rec. Q.2941.2 in particular) subsequent to the approval of ITU-T Rec. H.32
8、1 (02/98). Source Corrigendum 1 to ITU-T Recommendation H.321 (1998) was approved on 8 January 2005 by ITU-T Study Group 16 (2005-2008) under the ITU-T Recommendation A.8 procedure. ii ITU-T Rec. H.321 (1998)/Cor.1 (01/2005) FOREWORD The International Telecommunication Union (ITU) is the United Nati
9、ons 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 questions and issuing Recommendations on them with a view to standardizing telecommunicat
10、ions 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 approval of ITU-T Recommendations is covered by the procedure
11、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 “Administration“ is used for conciseness to indicate both a telecommun
12、ication 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 compliance with the Recommendation is achieved when all of these man
13、datory 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 is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws
14、 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 Intellectual Property Rights, whether asserted by ITU members or
15、others outside of the Recommendation development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementors are cautioned that this may not repre
16、sent the latest information and are therefore strongly urged to consult the TSB patent database. ITU 2005 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. ITU-T Rec. H.321 (1998)/Cor.1 (01/2005) iii CONTENTS Pag
17、e 1) Update to the list of normative references 1 2) Update to GIT End Station Identifier . 1 3) Update to Broadband Report Type IE 2 ITU-T Rec. H.321 (1998)/Cor.1 (01/2005) 1 ITU-T Recommendation H.321 Adaptation of H.320 visual telephone terminals to B-ISDN environments Corrigendum 1 1) Update to
18、the list of normative references Amend clause 2, References, as follows: 2 References ITU-T Recommendation I.580 (1995), General arrangements for interworking between B-ISDN and 64 kbit/s based ISDN. ITU-T Recommendation Q.2931 (1995), Digital Subscriber Signalling System No. 2 User-Network Interfac
19、e (UNI) layer 3 specification for basic call/connection control and its Ammendments. ITU-T Recommendation Q.2941.1 (1997), Digital Subscriber Signalling System No. 2 Generic identifier transport. ITU-T Recommendation Q.2941.2 (1999), Digital Subscriber Signalling System No. 2 Generic identifier tran
20、sport extensions. 2) Update to GIT End Station Identifier Amend clause 7.3 as follows: 7.3 Intercommunication between AAL-1 and AAL-5 The following procedures describe the use of an AAL-1/AAL-5 Interworking Unit as shown in Figure 7. 1) An H.321 terminal sends a SETUP to another H.321 terminal. If t
21、he AAL type of the receiving terminal matches the AAL type in the SETUP, the normal connection procedures are followed. 2) If the AAL type in the SETUP does not match the type of the receiving terminal, a Generic Identifier Transport (GIT) Information Element (IE) may optionally be included in the R
22、ELEASE COMPLETE. This GIT IE can contain the address of an AAL-1/AAL-5 Interworking Unit known to the destination terminal that rejected the call. NOTE The address shall be contained in the End Station Identifier which is pending definitionwith Identifier related standard/application (octet 5) = 000
23、00010 and approval from Study Group Identifier type (octet 6) = 00000011. 3) The originating H.321 terminal may use the address contained in the GIT IE from the RELEASE COMPLETE to send a new SETUP to the specified AAL-1/AAL-5 Interworking Unit. The address of the destination H.321 terminal shall be
24、 included as a GIT IE, since the SETUP itself addresses the AAL-1/AAL-5 Interworking Unit. 2 ITU-T Rec. H.321 (1998)/Cor.1 (01/2005) 3) Update to Broadband Report Type IE Amend clause C.4 as follows: C.4 Choosing between adaptive and independent clocks The procedures of this subclause apply only whe
25、n a network clock source is not available. They are designed to prevent both ends of a connection from choosing adaptive timing, which would create an unstable loop. If an H.321 terminal receives a Q.2931 call-related message with parameter “X“Type of report (00000010) in a Notification IndicatorBro
26、adband Report Type IE (IE Identifier = 10001001), the transmitter of that terminal shall use an independent clock source. When an H.321 terminal without a network clock source sends a SETUP message, parameter “X“Type of report (00000010) shall be included in the Notification IndicatorBroadband Repor
27、t Type IE and the transmitter shall prepare to use the adaptive clock of the receiver. It shall revert to an independent clock source if the response to SETUP or any later message contains parameter “X“Type of report (00000010) in a Notification Indicator IE.Broadband Report IE. NOTE Parameter “X“ i
28、s pending definition and approval from Study Group 11. An H.321 terminal shall be capable of providing both an adapted clock and an independent clock to its transmitter, whichever is called for in a given connection. Printed in Switzerland Geneva, 2005 SERIES OF ITU-T RECOMMENDATIONS Series A Organi
29、zation of the work of ITU-T Series D General tariff principles Series E Overall network operation, telephone service, service operation and human factors Series F Non-telephone telecommunication services Series G Transmission systems and media, digital systems and networks Series H Audiovisual and m
30、ultimedia systems Series I Integrated services digital network Series J Cable networks and transmission of television, sound programme and other multimedia signals Series K Protection against interference Series L Construction, installation and protection of cables and other elements of outside plan
31、t Series M Telecommunication management, including TMN and network maintenance Series N Maintenance: international sound programme and television transmission circuits Series O Specifications of measuring equipment Series P Telephone transmission quality, telephone installations, local line networks
32、 Series Q Switching and signalling Series R Telegraph transmission Series S Telegraph services terminal equipment Series T Terminals for telematic services Series U Telegraph switching Series V Data communication over the telephone network Series X Data networks, open system communications and security Series Y Global information infrastructure, Internet protocol aspects and next-generation networks Series Z Languages and general software aspects for telecommunication systems
