COMMUNICATIONS STANDARDS REVIEW TELECOMMUNICATIONS
Volume 9, Number 8 November-December 1998
In This Issue The following reports of recent standards meetings represent the view of the reporter and are not official, authorized minutes of the meetings. ITU-T SG16, Multimedia, September 14 – 25, 1998, Geneva, Switzerland...... 2 WP 1 Report...... 5 WP 2 Report...... 5 WP 3 Report...... 6 Q1/16 WP2, Audiovisual/Multimedia Services...... 6 Q2/16 WP2, Interactive Multimedia Information Retrieval Services (MIRS)...... 7 Q3/16 WP2, Data Protocols for Multimedia Conferencing...... 7 Q4/16 WP1, Modems for Switched Telephone Network and Telephone Type Leased Lines...... 9 Q5/16 WP1, ISDN terminal adapters, and interworking of DTEs on ISDNs with DTEs on other networks...... 10 Q6/16 WP1, DTE-DCE Interchange Circuits...... 11 Q7/16 WP1, DTE-DCE Interface Protocols...... 12 Q8/16 WP1, DCE-DCE Protocols...... 13 Q9/16 WP1, Accessibility to Multimedia for People with Disabilities...... 13 Q10/16 WP1, Modem Testing...... 15 Q11/16 WP2, Circuit Switched Network (CSN) multimedia systems and terminals...... 16 Q12/16 WP2, B-ISDN Multimedia Systems and Terminals...... 18 Q13/16 WP2, Packet Switched Multimedia Systems and Terminals...... 19 Q14/16 WP2, Common Protocols, MCUs and Protocols for Interworking with H.300-series Terminals...... 24 Q15/16 WP3, Advanced Video Coding...... 26 Q16/16 and Q17/16, Multimedia Harmonization and Coordination...... 28 Q18/16 WP1, Interaction of high-speed voiceband data systems with signal processing...... 30 Q19/16 WP3, Extension to existing ITU-T speech coding standards at bit rates below 16 kbit/s...... 31 Q20/16 WP3, Audio and Wideband Coding in Public Telecommunication Networks...... 32 Q21/16 WP3, Encoding of Speech Signals at Bit Rates Around 4-kbit/s...... 35 Q22/16 WP3, Software and Hardware Tools for Standardization of Speech and Audio Coding Algorithms...... 37 Q23/16 WP1, PCM Modems...... 38 Meeting Roster of Study Group 16, September 14 – 25, 1998, Geneva, Switzerland...... 49 ETSI TM6 Access Transmission Systems On Metallic Cables, September 21 – 25, 1998, Vienna, Austria...... 43 HDSL (High-rate Digital Subscriber Loop)...... 44 ANAI (Access Network Architecture and Interfaces)...... 44 SDSL...... 45 ADSL...... 47 VDSL...... 48 Working Party 1/15, Network Access, October 12 – 23, 1998, Geneva, Switzerland...... 51 WP1/15 Recommendations Approved at SG15...... 51 WP1/15 Recommendations Determined at SG15...... 51 Q1/15, Access Network Transport...... 51 Q2/15, Characteristics of Optical Systems in Local Access Networks...... 54 Q3/15, DCEs for Digital Leased Circuits...... 55 Q4/15, DCEs for Subscriber Access Systems...... 55 WP1/15 Partial Meeting Roster, October 12 – 23, 1998, Geneva, Switzerland...... 64 Acronym Definitions...... 68 1998 and 1999 Standards Committee Meeting Schedules...... 71
November-December 1998 Vol. 9.8 Copyright © CSR 1998 1 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF ITU-T SG16, MULTIMEDIA, SEPTEMBER 14 – 25, 1998, GENEVA, SWITZERLAND APPROVED RECOMMENDATIONS OF SG16 The following Recommendations, ordered by Recommendation, were approved by Resolution 1 (Decision) at this meeting. Q Decided Recommendation Document(s) Q19 G.729, Coding of speech at 8 kbit/s using conjugate-structure algebraic-code-excited COM 16-45 + linear-prediction, Annex C, Floating point TD-16(PLEN) Q19 G.729, Coding of speech at 8 kbit/s using conjugate-structure algebraic-code-excited TD-43(PLEN)© linear-prediction, Annex D, 6.4 kbit/s extension Q19 G.729, Coding of speech at 8 kbit/s using conjugate-structure algebraic-code-excited TD-44(PLEN) linear-prediction, Annex E, 12 kbit/s extension, 11.8-kbit/s CS-ACELP speech coding algorithm Q12 H.222.0|ISO/IEC 13818-1 Amendment 5, Information Technology -- Generic Coding of COM 16-67 Moving Pictures and Associated Audio Information: Systems Q13 H.225.0 Annex I, H.263+ Video Packetization COM 16-70 Q11 H.226, H.multilink, Channel Aggregation Protocol for Multilink Operation on Circuit COM 16-62 Switched Networks Q14 H.245v4, Control Protocol for Multimedia Communication: Support for H.multilink COM 16-59 Q12 H.247, H.bmultipoint, Multipoint Extensions for Broadband Audiovisual Communication COM 16-69 Systems and Terminals Q12 H.310 Version 2, Broadband Audiovisual Communication Systems and Terminals COM 16-68, + TD-15(PLEN) Q13 H.323 Annex D, Real Time Facsimile over H.323 COM 16-60 + TD-54(PLEN) Q11 H.324 Annex F, v2, Multilink Operation COM 16-61 Q13 H.332, H.323 Extended For Loosely-Coupled Conferences COM 16-41 + TD-14(PLEN) Q4 V.8bis revised, Procedures for the Identification and Selection of Common Modes of COM 16-63 + Operation Between Data Circuit-Terminating Equipment (DCEs) and Between Data TD-58(PLEN) Terminal Equipment (DTEs) over the Public Switched Telephone Network and on Leased Point-To-Point Telephone-Type Circuits Q23 V.90, A Digital Modem and Analogue Modem Pair For Use on the Public Switched COM 16-64 + Telephone Network (PSTN) at Data Signalling Rates of up to 56 000 bit/s Downstream TD-6(PLEN) and up to 33 600 bit/s Upstream Table 1. Recommendations Approved (Decided) at SG16, September 1998. DETERMINED RECOMMENDATIONS OF SG16 The following recommendations, ordered by Recommendation, were Determined at this meeting. Determination is the first step of the approval process. Determined recommendations are expected to be proposed for approval at the next SG16 meeting (May, 1999). Q Determined Recommendation Document(s) Q1 F.700 Annex B.2, Communication task conferencing TD-50(PLEN) Q1 F.700 Annex C.1, Control and processing element Conference control TD-50(PLEN) Q19 G.728 Annex H Corrigendum, Variable Bit Rate TD-CELP Operation Mainly for DCME at TD-49(PLEN) Rates Less Than 16 kbit/s Q19 G.728, Annex I, Frame or Packet Loss Concealment for the LD-CELP Decoder TD-48(PLEN) Q11 H.221, revised, Frame structure for a 64 to 1920 kbit/s channel in audiovisual teleservices TD-23(PLEN) Q12 H.222.0|ISO/IEC 13818-1 Amendment 6, Information technology – generic coding of TD-30(PLEN) moving pictures and associated audio information: systems Q11 H.223, Annex D, Optional multiplexing protocol for low bit rate multimedia TD-37(PLEN) communication over highly error prone channel Q13 H.225.0 Annex G, Gatekeeper to Gatekeeper Communications (Communication between TD-61(PLEN) Administrative Domains) Q11 H.230, revised, Frame-synchronous control and indication signals for audiovisual systems TD-20(PLEN)
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Q11 H.242, revised, System for establishing communication between audiovisual terminals TD-22(PLEN) using digital channels up to 2 Mbit/s Q14 H.245v5, Control protocol for multimedia communication TD-39(PLEN) + TD-28(PLEN) Q15 H.262, Amendment #5: Generic coding of video, High level for the 4:2:2 profile TD-26(GEN) Q3 H.282 (ex V.RDC), Remote device control protocol for multimedia applications TD-24(PLEN) Q14 H.283, (ex H.RDC) - Remote Device Control – Specific for H series recommendations TD-38(PLEN)© requirements Q11 H.320, revised, Narrow band visual telephone systems and terminal equipment TD-21(PLEN) Q13 H.323 Annex E (Call Connection over UDP) TD-47(PLEN) Q13 H.323 Annex F (Single Use Terminal) TD-51(PLEN) Q14 H.341, (ex H.Media MIB) - Multimedia management information base TD-27(PLEN)© Q13 H.450.4, Call Hold supplementary service for H.323 TD-34(PLEN) Q13 H.450.5, Call Park and Call Pickup supplementary services for H.323 TD-35(PLEN) Q13 H.450.6, Call Waiting supplementary service for H.323 TD-36(PLEN) Q13 H.450.7, Message Waiting Indication supplementary service for H.323 TD-40(PLEN) Q3 T.123rev, Network specific data protocol stacks for multimedia conferencing TD-26(PLEN)© Q3 T.136 (ex T.RDC), Remote device control application protocol TD-25(PLEN) Q8 V.14 Corrigendum , Transmission of Start-Stop Characters over Asynchronous Bearer TD-32(PLEN) Channels Q23 V.91 (V.adm), A digital modem for use on a switched digital network at data signalling TD-72(PLEN) rates of up to 64000 bit/s. Q5 V.120 Corrigendum, Support by an ISDN of DTEs with V-series type interfaces with TD-53(PLEN) provision for statistical multiplexing. Q7 V.250 revised, Serial Asynchronous Automatic Dialing and Control TD-56(PLEN) Table 2. Recommendations Determined at SG16, September 1998.
ADDITIONAL APPROVALS The following documents were also approved by the SG16 Plenary. Approval of these documents does not involve the full Resolution 1 procedures, which are required for Recommendations. Q Approvals Document(s) Q11 H.223 Implementor Guide, Multiplexing protocol for low bit rate multimedia TD-41(PLEN) + communication: Support of Annex C ((??)) TD-55(PLEN) Q13 H.323 Implementors Guide for the ITU-T H.323, H.225.0, H.245, H.246, H.235, and TD-60(PLEN) H.450 Series Recommendations – Packet based multimedia communication systems Q11 H.324 Implementor Guide, Terminal for low bit rate Multimedia communication: TD-29(PLEN) Support of Annex D Q4 V.8 Addendum (additional codepoints), Procedures for Starting Sessions of Data TD-59(PLEN) Transmission over the PSTN Q4 V.17 Corrigendum (technical error), A 2-wire Modem for Facsimile TD-33(PLEN) Applications with Rates up to 14400 bit/s Q9 V.18 Appendix 3, Connection Procedures for Terminals Including V.18 TD-73Corr(PLEN) Functionality Q9 V.18 Appendix 4, Specification of V.18 Implementation Tests TD-75(PLEN) Q9 V.18 Implementors Guide, Operational and Interworking Requirements for DCEs TD-74Corr(PLEN) Operating in the Text Telephone Mode Q23 V.90 Appendix, Typical Network Configuration TD-45(PLEN) Q7 V.250 Supplement, Serial Asynchronous Automatic Dialing and Control TD-57(PLEN)© Table 3. Additional Approvals at SG16, September 1998. SG16 GENERAL ISSUES SG16 has three Working Parties (WPs): WP Title Chair Mtg. Report WP1/16, Low Rate Systems J. Magill, Lucent (UK) TD-76(PLEN) WP2/16, Services & High Rate Systems F. Tosco, CSELT (Italy) TD-66(PLEN) WP3/16, Signal Processing S.F. Campos Neto, Comsat (US) TD-62(PLEN)
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Questions 16/16 and 17/16 are under SG16, not associated with a specific Working Party. SOFTWARE COPYRIGHT ISSUES
Background - February 1998 meeting of SG16 At the February 1998 meeting of SG16, the subject of the ownership of software copyright arose in relation to speech coding Recommendations. In particular, G.729 Annex C was to be approved at that meeting, but during the SG16 plenary, Germany opposed approval, and requested a further four weeks to consider their position, as allowed by Resolution No. 1 procedures. They had concerns about the procedures being used for the release of the C-code prior to approval. The C-code was only released to ITU members wishing to evaluate the code and who had signed a Software Release Letter (SRL). In the case of G.729 Annex C, there had been further administrative errors and Germany had only received the final code during the meeting. However, Germany’s prime concern was that the copyright for the C-code included in the Annex was retained by the authors rather than being transferred to the ITU. In view of the difficulties arising at the SG16 meeting, the Chairman of WP3/16, S. Campos Neto, led an e-mail discussion group on this subject in the interim period between SG16 meetings. During the four week period after the meeting, Germany confirmed their objection and the approval of G.729 Annex C failed. Their stated reasons were: • The copyright of the C-code is retained by the authors; • The need for a Note saying that the definition of the Voice Activity Detection (VAD) is for further study; • The need for text clearly stating that the C-code takes precedence over the text. Interim Period Some exchange of e-mail took place during the interim period but no conclusion was reached. Germany confirmed their position. This was followed by views from France, the UK, the University of Sherbrooke/Sipro Labs, and Pic- tureTel. These were broadly in line and proposed that the ITU have a copyright policy similar to the existing patent policy, i.e., authors would not be required to transfer the copyright to the ITU, but could license free or on fair, reasonable and non-discriminatory terms. During this period it also became clear that the subject would be addressed the ITU-T TSAG (Telecommunications Standardization Advisory Group). Meeting of TSAG (Telecommunications Standardization Advisory Group) There were contributions to TSAG from Germany, UK, France, and the USA. These were in line with the positions discussed above, with the USA also supporting a copyright policy similar to the patent policy. The issue was ad- dressed by an ad-hoc group chaired by the Director of the ITU TSB, Dr. T. Irmer. There was considerable discussion, but no support for the German position. The ITU Legal Department confirmed that they did not require transfer of copyright, but only a license to copy, distribute, sell, etc., and indeed would prefer not have the copyright to avoid any possible legal implications. The conclusion was a first draft of an ITU copyright policy which permitted free licensing, and licensing on fair, reasonable and non-discriminatory terms (as for the patent policy), with the additional option of transfer of the copyright to the ITU. The policy also defined other obligations for the copyright holder, i.e., granting the ITU a royalty-free license to reproduce, publish, sell, and distribute the software; and granting users a free license for evaluation and test purposes; it was stated that the addition of other obligations was for further study. With this compromise in place, although it was recognized further work was required to complete the copyright policy, the Chairman of TSAG indicated his belief that there should now be no barrier to the approval of Recommendations because of copyright issues. This was endorsed by the TSAG meeting. TD-12(PLEN) is the report of the TSAG meetings on copyright and patents September 8 - 10, 1998. SG16 Plenary The approval of Recommendations, including G.729 Annexes C, D, and E, was considered at the SG16 opening Plenary session (September 15, 1998). The Recommendations were taken in Working Party order, thus the G.729 annexes were at the end of the list (in WP 3). The French Administration was concerned that, despite the progress made at TSAG, the issue of copyright would still arise. They felt that it was not appropriate for SG16 to address, and would result in SG16 being inconsistent in its approach to the approval of Recommendations. As a result, when approval of the first Recommendation on the list was requested, France requested four weeks for further consideration, and noted that this applied to all Recommendations for approval. When approval of the G.729 Annexes was requested, as expected by France, Germany requested delaying approval until the closing Plenary such that the TSAG compromise could be developed to define further obligations for copyright holders, i.e., the issue left for further study by TSAG. France strongly opposed this on the grounds that this was outside the scope of SG16 considerations. After much debate, a compromise was reached in which words would be added to the Annexes stating simply that the issue of copyright for the C-code might be revised after TSAG had completed its work. On this basis, the Annexes were approved with France revoking its four week request for all the Recommendations.
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LIAISONS The next SG13 plenary meeting will take place February 15-26, 1999 in Geneva. TSAG guidelines on interoperability experiments are provided in TD-10(PLEN). This is a draft supplement laying out how the administrative procedures for interoperability testing should be carried out on a per recommendation basis. PRESS OFFICER M. Buckley (Lucent Technologies, “elemedia” Business Unit) was appointed to the new post of Press Officer for SG16. NEXT SG16 MEETING Study Group 16 received an invitation from the University of Chile and the Chilean Administration to hold the next meeting of SG16 in Santiago, Chile, May 18-28, 1999. This will follow a Multimedia seminar at this location on May 17, 1999, which is World Telecommunications Day. SG16 agreed to accept this invitation subject to confirmation being received by the SG16 management team that the necessary meeting facilities will be available. The Study Group also agreed that, as an exception, this meeting could take place in English without simultaneous translation into the other working languages. Translation into Spanish may be available during some sessions for the benefit of local attendees. If any problem arises such that the meeting in Chile cannot take place, the SG16 meeting will revert to the original dates, April 19-30, 1999, in Geneva. WP 1 REPORT The WP 1 report for this meeting is TD-76(PLEN). The WP 1 liaison statements are in TD-77(PLEN), the status report for WP 1 Recommendations in TD-78(PLEN), and a list of proposed WP 1 interim meetings is in TD-79(PLEN). REVISIONS TO QUESTIONS IN WP1/16 The WP 1 Chairman (J. Magill, Lucent) pointed out the need to review the text of the Questions under study by WP1/16, considering the overlap in the studies of Q4/16 and Q23/16, and that some Questions received very few contributions. The following was proposed for consideration prior to the next SG16 meeting: • Combine all modem modulation issues in Q23/16, i.e., move the modulation study item from Q4/16 to Q23/16 • Retain the other study items in Q4/16 • Add to Q4/16 the responsibility for coordinating work on modem managed objects • Revise the titles of Q4/16 and Q23/16 accordingly Additionally, consideration should be given to whether the study of issues arising from the use of modems and ISDN TAs for connection to IP networks need to be added to Questions in WP1/16, and whether other existing Questions could be combined. WP 2 REPORT The WP 2 report of this meeting is contained in TD-66(PLEN), TD-67(PLEN) and TD-68(PLEN). TD- 65(PLEN) is a list of documents composing the WP 2 report, TD-69(PLEN) are liaison statements, TD- 70(PLEN) lists the WP 2 planned rapporteur meetings, and TD-71(PLEN) is the status report for WP 2 Recommendations. WP 3 REPORT TD-62(PLEN) is the WP 3 report of this meeting; TD-63(WP3/16) lists the WP 3 liaison statements, and TD-64(WP3/16) is the WP 3 status report. AD -HOC GROUP ON TRUNKING/PACKETIZATION MATTERS A number of coded speech trunking and packetization activities are going on in different standard development organizations (SDOs); WP 3/16 established an ad-hoc group at this meeting to deal with the matter.
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The trunking/packetization ad-hoc group’s main action was to review the text of I.TRUNK, AAL type 2 service specific convergence sublayer for trunking, (I.366.2 developed under Q5/13, see TD-2(WP3/16)), where a number of packetizations were checked, and the necessary definitions for G.729 Annexes D (6.4 kbit/s) and E (11.8 kbit/s) which were approved at this meeting were identified. The suggested changes were provided in a liaison statement to SG13. TD-31(WP2/16) from the ATM Forum, which includes BTD-SAA-RMOA-01.04, H.323 media transport over ATM, was reviewed. This liaison also clarifies an earlier liaison from the ATM Forum. The ATM Forum’s method of transporting H.323 over ATM is intended to cover the typical scenario where the endpoints are on non- ATM IP networks as well as the scenario where the endpoints are on ATM networks. As this method is independent of the underlying network, it is the intention of the ATM Forum TC to not request any modifications to the H.245 protocol. After review of TD-31(WP2/16), SG16 WG3 requested that a clarification be added in the opening paragraph of Annex A, Guidelines for choosing voice packet sizes, clarifying that the considerations in Annex A address efficiency aspects, which should be counterbalanced by the impact of packetization choice on the end-to-end delay. The group would also like to note that the packetization considerations could also be made for G.726 and G.727. Additionally, the embedded scheme available in G.727 could be efficiently used for network congestion control. TD- 25(WP3/16) has the text of the proposed communication to the ATM Forum. Q1/16 WP2, AUDIOVISUAL/MULTIMEDIA SERVICES The Rapporteur of Q1/16 is Y. Robin-Champigneul (FT/CNET, France). The report of Q1/16 going into this meeting is TD-33(WP2/16). A rapporteur’s meeting is planned with Questions 16-17 in January 1999 in Tokyo. The ITU Reflector for Q1/16 is [email protected] RECOMMENDATION F.700 - FRAMEWORK RECOMMENDATION ON MULTIMEDIA SERVICES The list of control and processing elements (CPEs) was reviewed and slightly amended. The example of CPE description on conference control provided in D.182© (Y. Robin-Champigneul, France Telecom) was accepted and will be added to F.700 as a new Annex C.1. Its structure will be used for other CPE descriptions. Annex B.2 on the communication task conferencing has been revised accordingly. Final versions which were Determined appear in TD-50(PLEN). Amendments to Sections 1 and 3 of F.700 will be drafted before the next meeting in order to include the CPEs in the reference model. Section 2 (application scripts) was reviewed in the light of the amendments proposed in TD-24(WP2/16) (Y. Robin-Champigneul, France Telecom). The revised text of this Section is now complete and will be further discussed by correspondence if needed. The revised version of F.700 is planned for Determination at the next SG16 meeting. Work on the Guide for Recommendation F.700 will be continued. Other CPEs descriptions will be drafted, beginning with Search control, Resource allocation, Call control and a CPE on security. DRAFT RECOMMENDATION F.MRS - MULTIMEDIA RETRIEVAL SERVICES The Editor for this recommendation has resigned because he is not able to attend the meetings any more. No other expert on retrieval services was present, so that the drafting is halted until a new editor can be found. APPLICATION SCRIPTS FOR MULTIMEDIA RETRIEVAL SERVICES The new application script provided by the Associate-Rapporteur was examined and accepted; it was decided to retain also the previous one because they are complementary. GII PROJECTS Question 1/16 will participate in the new GII Project M.3, Technical framework for electronic commerce, for which SG16 is now the lead SG. Electronic commerce is an application that mainly uses retrieval services. A document will be drafted describing the application. Its nature and relation to service descriptions will be decided later on. Question 1/16 will also participate in GII Project F.4, End-to-end interoperability, for which it is proposed to provide scenarios for interoperability of services and interoperability profiles.
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Additionally, the description of the CPE Conference control will be provided to GII Project M.4, Middleware for Multimedia, as a possible example of service-oriented middleware. See the Q16/17 report below for additional details. JOINT MEETING WITH QUESTION 9/16 A joint meeting of Questions 1/16 and 9/16 examined the various cases of using multimedia conversational services for hearing impaired or visually impaired people. An application script will be drafted in order to show their particular needs. It will be taken into account in the drafting of the future Recommendation F.MCVS, Multimedia Conversational Services. Drafting of Recommendation F.MCVS - Multimedia Conversational Services, will start using the contents of Recommendation F.720 on the videotelephony service, and will take into account the script that will be provided by Question 9/16. Q2/16 WP2, INTERACTIVE MULTIMEDIA INFORMATION RETRIEVAL SERVICES (MIRS) The Q2/16 Rapporteur is M. Blaschitz (INFONOVA, Austria). No interim meetings are scheduled for Question 2. TD-83(WP2/16) is the Q2/16 meeting report. MODIFIED WORK PLAN FOR GII-P ROJECT M.4 TD-5(PLEN) is a report on the GII developments since the last SG16 meeting (see GII report above). A revised work plan was created which takes the middleware-related work of SG10 and SG13 into account and focuses on the areas which are not covered by these groups. Two liaisons (to Q24/13 and JRG on GII, SG10, SG13) noting the work in Q2/16 on the GII project M.4 were approved. MULTIMEDIA MIDDLEWARE TD-20(GEN) is a liaison from SG10 to JRG on GII and relevant SGs. It provides a detailed report on the middleware standardization activities in ITU-T SG4, SG7, SG10, SG13 and SG16 also ETSI, OMG (CORBA), ACTS, TINA-C, and EURESCOM. Q2/16 acknowledges the request, TD-19(GEN), from SG10 to focus on the definition of requirements for Multimedia Middleware. TD-42(PLEN) is a requirements document concerning the M.4 Project “Middleware for multimedia.” It is technically aligned with the DAVIC Specification 1.4 part 1 (Description of digital audio-visual functionalities, available at www.davic.org). It specifies required functions to implement different categories of multimedia systems supporting specific applications. It was approved to be sent as part of the liaison to JRG GII, SG10 and SG13. Q3/16 WP2, DATA PROTOCOLS FOR MULTIMEDIA CONFERENCING The Q3/16 Rapporteur is B. DeGrasse (DataBeam, USA). TD-56(WP2/16) is the agenda. TD-69(WP2/16) is the meeting report. Q3/16 plans to meet once in the interim, January 19-21, 1999 in California. TD- 19(WP2/16) is the Q3/16 status report of the work since the last SG16 meeting. T.120 SECURITY REQUIREMENTS TD-25(WP2/16)©, Draft Rec. T.123, network-specific data protocol stacks for multimedia conferencing of the T.120- series of data protocols. The networks currently identified are: ISDN Integrated Services Digital Network CSDN Circuit Switched Data Network PSDN Packet Switched Data Network PSTN Public Switched Telephone Network B-ISDN Broadband ISDN LAN Local Area Network Communication profiles are specified which provide reliable point-to-point connections between a terminal and a multipoint control unit, between pairs of terminals, or between pairs of MCUs. In some cases, a lower protocol layer allows the multiplexing of audio, video signals in addition to data connections. In other cases, separate calls, over the same or a different network, may be established to carry audio or video signals.
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In addition, Annex B of T.123rev (Extended transport connections) specifies a protocol (based on X.224.0) that may be used to negotiate connection devices beyond reliable data transfer (e.g., security options). This protocol also provides for the use of alias lists when making a connection. Alias lists will allow proxy services for T.120 communications to be created and used. TD-44(WP2/16) (P. Murphy, DataBeam) contains proposed changes to the Annex B ASN.1 by importing ASN.1 structures it shares with other protocols rather than replicating them. It was accepted. TD-45(WP2/16) (P. Murphy, DataBeam) contains a method for performing segmentation and reassembly for the unreliable PSTN profile described in section 8.2.2 of T.123rev Annex B. It was accepted. Q3/16 discussed additional security requirements for the T.120 series of recommendations. An ad hoc group met, and made recommendations. Q3/16 then proposed a three step, phased approach for addressing the security issues of T.120 series recommendations. Phase 1: Securing T.120 entities against outsiders attacking from the network. This first phase security provides security countering the most crucial network security threats. Phase one focuses on the lower T.120 communication layers (T.123) and attempts to provide at least some solutions in particular cases by using available security standards as appropriate for securing T.120 conferences (e.g., IETF’s Transport Layer Security Protocol TLS for unicast Internet IP). Thus, basic security is provided to protect T.120 conferences against intruders attacking a conference from the outside. Phase 2: Securing the T.120 infrastructure target (MCS, GCC and MAP) countering weaknesses within a node and inside a conference. Phase 3: Security for and within the T.120 applications and security against insider attackers (e.g., securing T.128). Contributions are requested. T.123rev was Determined as TD-26(PLEN)©. REMOTE DEVICE CONTROL D.207©, V.RDC (A. Woollett, ImageCom), describes the core services and protocol for performing configuration and control of a remote device during a multimedia conference. This recommendation does not specify the use of a particular transport protocol. D.208©, T.RDC (A. Woollett, ImageCom), describes how remote device control may be performed using T.120 as the transport protocol. The core remote device control services and protocol are described in D.207©. TD-22(WP2/16), H.RDC (M. Duckworth, PictureTel), describes how the core remote device control services work with systems using packet switched networks. It defines a new Data Link Protocol to carry Common RDC (that part of RDC common to both T.120 and H.323) within UDP over an H.245 logical channel. Q3/16 accepted D.207© and D.208© with minor editing changes and agreed to submit them for Determination. These draft recommendations with the agreed to editing changes were Determined as H.282, TD-24(PLEN) (V.RDC), and T.136, TD-25(PLEN) (T.RDC). BINTERMS CONSORTIUM PRESENTATION J. Korinthios (Teletel, Greece), on behalf of the BINTERMS Consortium, made a presentation about the activities carried out in the BINTERMS (Basic Interoperability of Terminals for Telematic Services) Project. This Project, supported by the European Union ISIS (Information Society Initiatives in Standardization) Program, validates key components of the T.120 protocol specifications for functional and syntactic completeness, using an SDL representation of the MCS (Multipoint Communication Service) and GCC (Generic Conference Control). It also produces detailed test specifications (ATS–Abstract Test Suite) for MCS and GCC, using TTCN (Tree and Tabular Combined Notation). The BINTERM web site (www.solinet.com/binterms) provides copies of the deliverables including a report of the T.120 aspects of unsuccessful and/or illegal behavior. TD-66(WP2/16) contains a draft liaison to the BINTERM project thanking them for their excellent presentation and their deliverables. Q3/16 members are asked to review the deliverables with the view to improving the current work.
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VIRTUAL MEETING ENHANCEMENTS No contributions were received on this issue. Q4/16 WP1, MODEMS FOR SWITCHED TELEPHONE NETWORK AND TELEPHONE TYPE LEASED LINES The Rapporteur for Q4/16, D. Stuart (3Com), had to leave the meeting early due to other work; L. Brown (Motorola), Rapporteur for Q23/16, agreed to chair the Q4/16 sessions. As D. Stuart is also Rapporteur for Q4/15 (DSL) which is a very active Question, he felt no longer able to continue as Rapporteur for Q4/16. WP1 agreed that B. Adams (Hayes, USA) would take over as Rapporteur for Q4/16. With the revisions to the scope of Q4/16 (see WP1 Report, above), it would include the responsibility for Recommendations V.8, V.8bis, V.70 and V.75, thus eliminating the need for the Associate Rapporteurs L. Brown and C. Hansen (Intel). L. Brown (Motorola ISG, USA) is the Q4/16 Associate Rapporteur for V.8 and V.8bis. The V.8-V.8bis agenda is TD-18(WP1/16). TD-16(WP1/16) is the report of the Red Bank, New Jersey, V.8/V.8bis interim Rapporteur meeting, May 1998. One interim Rapporteur’s meeting is planned for December 7-10, 1998 in California to progress the work on a draft Appendix to V.8bis on V.8/V.8bis interworking, and to progress the work on managed objects for modem diagnostics. REVISIONS TO V.8 TD-2(WP1/16) is a liaison from SG8 requesting the assignment of a V.8 information category for their use, similar to the existing SG8 codepoint category in V.8bis. The group agreed to assign a new information category to SG8 for their use. The assignment of this new information category is included in an Addendum to V.8, TD- 59(PLEN), that ws approved by the SG16 plenary. The liaison reply is in TD-60(WP1/16). REVISIONS TO V.8BIS Q4/16 held a joint meeting with Q9/16. See the Q9/16 report for further discussion. The group considered the following documents: D.153©, Comments on V.8 and V.8bis Related to V.18 (A. Farquharson, BT) TD-25(WP1/16), Proposals for Changing the Way V.18 uses V.8 and V.8bis (A. Farquharson, BT) TD-28(WP1/16), Modification Proposals to V.8bis COM 16-63 (G. Hellström, Q9/16 Rapporteur) TD-29(WP1/16), Use of V.8bis for Multifunction Terminals (G. Hellström, Q9/16 Rapporteur) As a result of discussion in the joint meeting, the group approved a minor clarifying editorial amendment to the draft of V.8bis (COM 16-63); it was approved (Decided) at the SG16 closing plenary. These amendments are detailed in TD-58(PLEN). The group also agreed to work on an Appendix for V.8bis describing interworking scenarios for multifunction devices that support V.8 and/or V.8bis. RECOMMENDATIONS V.70 AND V.75 There were no contributions on this topic and no discussion. No interim meetings are required. MODEM MANAGED OBJECTS D.210© (F. Lucas, USA) proposes that SG16 define a set of managed objects for modem diagnostics, and asks under which Question the work should be progressed. The group agreed that this work should progress primarily under Q4/16. K. Chu (Rockwell, USA) was appointed as the editor for this work. D.198©, Managed Objects for Modem Diagnostics (K. Chu, Rockwell), provides an initial basis for discussion. V.17 CORRECTIONS D.218 points out two typographical errors in Recommendation V.17: one in Table 3 bridge signal/resync and one in para 3.7 circuit 109 off threshold. The group generated a corrigendum, in TD-33(PLEN). TD-54(WP1/16) is a liaison to SG8 informing them of the corrections to V.17. The corrections were approved by the SG16 plenary.
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Q5/16 WP1, ISDN TERMINAL ADAPTERS, AND INTERWORKING OF DTES ON ISDNS WITH DTES ON OTHER NETWORKS The Q5/16 rapporteur is J. Moughton (Hayes, UK). TD-27(WP1/16) is the Q5/16 Agenda. The main activity of the meeting consisted of reviewing the proposed revisions to V.110, which resulted from problems of interpretation of the existing text. In addition there was continued liaison with SGs 11 and 13 in order to maintain the alignment of various V-series Recommendations with those that are the responsibility of the other study groups. Also, it was agreed to update V.130 (ISDN terminal adaptor framework) to add information on interworking with DTEs on other networks, in particular those connected to PCM digital networks. TD-1(WP/1) is a liaison statement from SG13. It notes that the revisions requested by SG16 for Recs. I.460 (ISDN user-network interfaces - Multiplexing, rate adaption and support of existing interfaces) and I.464 (ISDN user- network interfaces - Multiplexing, rate adaption and support of existing interfaces for restricted 64 kbit/s transfer capability) had been incorporated into the Recommendations which were Determined at the SG13 meeting in June 1998. TD-11(GEN) is a liaison from SG11. SG11 had made some of the requested amendments to Q.931 (ISDN user- network interface layer 3 specification for basic call control). However, the request for new modem type code points had not been implemented, apparently due to the belief that new user rate code points (in short supply) were also needed. The meeting drafted TD-26(WP1/16) in reply. TD-26(WP1/16) explains that the addition to Q.931 of new modem type code points does not necessarily imply the addition of new user rate codepoints and so the present shortage of the latter need not delay the allocation of the former. It repeats the request for code points for V.32bis, V.18 and V.90 (analog and digital) modems. V.110 - PROPOSED REVISION V.110 is titled, Support of data terminal equipments with V-series type interfaces by an integrated services digital network. TD-8(WP1/16), V.24 control circuit handling in V.110-based products (J. Moughton, UK), discusses some problems that have been encountered (by Vodafone in the UK) in the interpretation of V.110, both in implementations and in derivative GSM standards. These problems cause unexpected and unwanted clearing of mobile data calls. TD-9(WP1/16), Draft revised Recommendation V.110 (J. Moughton, UK), is a proposed revised text of V.110 in which the areas of confusion are clarified. In order to allow members to examine the text and consider the impact on compatibility with existing equipment, it is proposed that Determination of any revisions should take place at the next meeting of SG16. In the interim, the work will be progressed by correspondence. In addition to the changes proposed in TD-9(WP1/16), it was suggested that the structure of the document should be brought more into line with current ITU-T practice. V.120 PROPOSED AMENDMENT Q5/16 accepted D.147© (D. Moughton, UK), a proposal that the lists of modem type and user rate code points in V.120 (Support by an ISDN of data terminal equipment with V-series type interfaces with provision for statistical multiplexing) should be replaced by references to Q.931, thus ensuring consistency with any future revisions of Q.931. The changes will be published as a corrigendum (TD-53(PLEN)). TD-53(PLEN) was Determined by SG16. V.130 PROPOSED REVISION Q5/16 agreed that V.130 should be revised to add information on interworking between DTEs attached to the ISDN and DTEs on other networks, in particular those connected to PCM digital networks. V.140 - ALIGNMENT OF FRENCH AND ENGLISH TEXTS The Rapporteur informed Q5/16 that the French text for V.140 (Procedures for establishing communication between two multiprotocol audiovisual terminals using digital channels at a multiple of 64 or 56 kbit/s) differed in some details from the original English text. The TSB has been notified and the errors in translation will be corrected. Q6/16 WP1, DTE-DCE INTERCHANGE CIRCUITS The Q6/16 Rapporteur is R.R. Damm (Deutsche Telekom, German). TD-20(WP1/16) is the agenda. Q6/16 and Q7/16 had been given permission to hold up to four interim meetings to define new interface Recommendations in support of the work on xDSL equipment under Q4/15. The Rapporteur for Q4/15 gave a
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verbal update on this issue to the WP1 Plenary. He thanked the Rapporteurs for Q6/16 and Q7/16 for attending the meetings of Q4/15, and reported that SG15 had concluded that no new interface Recommendations were required at this time. As a result no interim meetings of Q6/16 and Q7/16 took place. DTE-DCE INTERFACES FOR XDSL MODEMS The Rapporteur reported that he had participated in four Q4/15 Interim Meetings on behalf of Q6/16. He had submitted to Q4/15 a contribution summarizing candidate interfaces for xDSL equipment, but it was decided by the Q4/15 group not to reference any particular type of DTE-DCE interface in draft Recommendations G.lite and G.dmt. FUNCTIONAL DESCRIPTION OF INTERFACES D.172© (G. Sebek, France Telecom) expresses concern that the necessary functional description of adaptation functions associated with a number of increasingly used interfaces like G.703 (Physical/electrical characteristics of hierarchical digital interfaces, supporting PDH/SDH/ATM structures), G.703/G.704 (Synchronous frame structures used at 1544, 6312, 2048, 8488 and 44736 kbit/s hierarchical levels), 10BASE-T, 100BASE-T (ISO/IEC 8802-3), ATMF 25.6 are not dealt with in present ITU-T work. Such work should include, according to France Telecom: • Physical aspects • Functional aspects (including timing, control, protocol and maintenance requirements such as control of test loops) • Necessary primitives from/to core or transmission functions of the DCE • End-to-end aspects (e.g., Quality of Service [QoS] checking and report) It was further suggested that SG16 define an action plan to cover the necessary specification for a number of additional DTE-DCE interfaces like the ones mentioned above. Q6/16 feels that such work would involve not only SG16 but also other Study Groups, e.g., those dealing with QoS, and that some sort of coordination or supervision would be necessary. The discussion was inconclusive; it was noted that the contribution also addressed Questions 7/16 and 8/16. Further contributions were invited. REVISION OF RECOMMENDATION V.24 D.167© and D.167 Amendment 1 (R.R. Damm, Deutsche Telekom) contain a proposal for a substantial revision of Recommendation V.24, including, among other things, the deletion of a number of interchange circuits, the addition of statements as to the sensitivity of control and indication circuits and a restructure of the Recommendation. One of the circuits proposed for deletion was cct. 128 (Received signal element timing [DTE source]). After a short discussion, it was decided that this be retained, and its definition be expanded so as to include its application for data flow control, specified in the new Recommendation V.43 (Data flow control). Given the amount of other changes, it was decided that the proposals be discussed in the National Standardization Bodies with the intention to Determine a revised Recommendation V.24 at the next meeting of SG16. J. P. Blin (France Telecom) suggested one new interchange circuit to be included in V.24, tentatively referred to as “Transmitted character timing (DTE source)”. One application of this circuit, for which there is already a need, is for video conferencing equipment. J.P. Blin envisaged a contribution from France Telecom to be submitted to the next meeting, wherein the requested functionality of the circuit would be specified. It was noted that • The definition of a complementary circuit, i.e., cct. 131 “Received character timing,” where the DCE is the source, already exists and has been in Recommendation V.24 for a long time, • It may be worthwhile to define one more complementary circuit, “Transmitted character timing (DCE source)” in order to be prepared for future needs, • The work should be completed at the next meeting of SG16 in order to be able to Determine a revised version of V.24 at that time. ADDITIONAL HIGHLIGHTS It was noted that a liaison statement requesting a similar circuit in Rec. X.24 (like the one requested by France Telecom) had been sent to SG7 from the last meeting of SG16, but that no response had been received. It was the feeling of the group that there might be no more experts on interfaces in SG7. The Rapporteur questioned whether it should be proposed to SG7 to transfer the responsibility for interface related X.-series Recommendations, i.e., X.20, X.20bis, X.21, X.21bis, X.24 and X.150 to Q6/16, so as to maintain maintenance of these Recommendations in future. There was support for the proposal and no objection.
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Q7/16 WP1, DTE-DCE INTERFACE PROTOCOLS The Q7/16 Rapporteur is F. Lucas (3Com, USA). TD-10(WP1/16) is the Q7/16 agenda. Q7/16 had been authorized to hold four interim meetings with Q4/15 and Q6/16, to progress work on interfaces for xDSL DCEs. These meetings were not held after Q4/15 decided not to include specific DCE-DTE interfaces in their draft Recommendations (TD-3(WP1/16)). REVISION OF V.250 (EX V.25TER, AT COMMANDS) Q7/16 met jointly with Q9/16 to consider two contributions to Q7/16 which also concerned Q9/16. See also the Q9 report for additional details. D.211© (R. Brandt, US) proposes the addition of a third variable, Initiate probing, under the probing_en subparameter in the +MV18S command. The joint meeting discussed this proposal and accepted it. D.211© also proposes the addition of a new +MV18PS command to provide for the storing of the V.18 probing message. It was pointed out that the +MV18AM command is already used for this function. The group agreed that, since it was not obvious that this command is used for the probing message, clarification of the wording of the Description and Defined values were needed. In addition, the value of the +MV18AM parameter was changed from
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TD-23(GEN) from ITU-R (Y. Nakata, Fuji Television Network) provides a tutorial on the use of computer technology in television broadcasting applications and the potential integration of PCs and TVs. It discusses receiving equipment, broadcasting services, current display technology (e.g., WebTV), APIs, ISDN, NTT Open Computer Network, FTTH, NTT Pi system and MPEG standardization activities. D.172© (G. Sebek, France Télécom) had been considered at length in the Q6/16 meeting. It was not entirely clear what Q8/16 could do to help with the proposed work although G. Sebek explained that, for example, there would be a need to provide a data channel for management purposes in conjunction with various new types of DCE. The Rapporteur expressed doubts that the group had the skills necessary but it was agreed to wait for more specific con- tributions on the topic and then re-assess the situation. D.148© (J. Moughton, UK) points out that Recommendation V.14 specifically limits its use to rates not greater than 19.2 kbit/s. This is inappropriate now that V.14 is used in V.34 modems and ISDN TAs. It was agreed to re- move the two references to the maximum rate as proposed in D.148©. The Rapporteur agreed to draft a Corrigendum. TD-32(PLEN) was approved by WP1 and SG16. It was agreed that maintenance of Recommendation V.14 be included in the list of Recommendations which are the responsibility for Q8/16. Q9/16 WP1, ACCESSIBILITY TO MULTIMEDIA FOR PEOPLE WITH DISABILITIES The Q9/16 Rapporteur is G. Hellström (Sweden). Q9/16 met not only individually, but in many joint sessions with different groups. TD-50(WP1/15) is the Q9/16 report of this meeting. V.18 A test specification for the V.18 text telephone interworking modems was accepted. The procedures for using V.8 and V.8bis for initial start-up of a text telephone session were clarified and documented. That means that it is now easier to merge text telephony and other multimedia features. Minor corrections to V.18 are now documented in a V.18 implementer’s guide. Specification of text conversation through diverse multimedia systems have made progress. It was agreed to work on text through H.320 with Q11/16 and on H.323 with Q13/16. The following documents were submitted to and approved by the SG16 final plenary: TD-73Corr(PLEN), V.18 Appendix 3: Connection procedures for terminals including V.18 functionality TD-75(PLEN), V.18 Appendix 4: Specification of V.18 implementation tests. Based on D.144© from BT, this document contains a set of tests for verification of a V.18 implementation. TD-74Corr(PLEN), V.18 Implementer’s guide, contains a number of corrections to V.18. DRAFT DOCUMENT INTENDED TO BE AN H.263 SUPPLEMENT TD-35(GEN), Draft H.263 Supplement, Application Profile: Sign Language and Lip-reading real time conversation usage of low bitrate video communication (G. Hellström, Q9/16 Rapporteur), is an informative guide for implementers who want to make video communication systems usable for sign language and lip-reading. The document will be proposed for approval at the next Study Group 16 meeting. SERVICE DESCRIPTION FOR MULTIMEDIA CONVERSATION SERVICES The theme of F.700 type service definitions was discussed jointly with Q1/16. The concept seems useful and needed, and Q9/16 would like to see Q1/16 activities used to create service descriptions. TD-30(GEN) (G. Hellström, Q9/16 Rapporteur) is a brief prose description of Multi-modal conversation. It was presented as a starting point for the general multimedia conversation service including features that make it accessible and valuable to people with disabilities. Application scripts for disability specific applications was discussed. G. Kelley (US) took on the task to produce a first proposal before mid November. TEXT CONVERSATION IN H.320, H.323, H.324, T.120 AND MOBILE Mobile The Liaisons to ETSI and a US group on mobile data asking to include V.18 in the mobile services interworking units to enable harmonized and interworking mobile text services have not been answered. A further opportunity to promote V.18 exists at an ETSI SMG 4 meeting directly after the SG16 meeting.
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The request for codepoint for V.18 in Q.931 mainly for mobile was answered negatively by SG11. Q5/16 handled the repetition of the request (TD-26(WP1/16)). H.324/M or H.323/M are feasible protocols for future mobile text conversation. These protocols can be used without video to give simultaneous text and voice. Q9/16 had the opportunity to describe to ETSI SMG what is needed to make UMTS (Universal Mobile Telecommunications System) multimedia services accessible. A draft document was released that describes the requirements for successful application in the area of video communication for sign language and lip reading. It is called an application profile and is a joint action with Q15/16. In a meeting of ETSI SMG 1, 4, and 12, the Q9/16 Rapporteur presented an overview of accessibility to UMTS services, indicating a need and solutions for text conversation, video quality of service for sign language and lip reading, retrieval services with alternative presentation forms and call control procedures with alternative presentation forms. R. Cox (AT&T) presented a method to transmit data in the voice channel of mobile systems by using an extension to the audio coding packet. Q9/16 found it valuable to know that this opportunity exists if needed when designing the text conversation in mobile systems. H.320: A simple channel for text conversation is needed in H.320. Therefore, description of a channel for T.140 text conversation through H.320 is now included in the plans of Q9/16 and Q11/16. Initial investigations indicate that a H.224-based channel seems suitable. See also the Q11/16 report, below. H.323: The modifications to H.245 already done for T.140 text conversation through H.324 makes a simple channel for text nearly ready through H.323. A description of the setup of the T.140 channel may be needed. This is to be taken into the plan for Q9/16. One item that may be the most important decision in the meeting was to start work on a simple IP text telephone for text and voice. That work is to take place in Q13/16 as an extension to work with a simple IP voice phone. TD-31(GEN) (G. Hellström, Q9/16 Rapporteur) proposes an IP text telephone to be included in the plans of Q13/16. It was accepted by Q13/16. TD-48(WP2/16) is Draft Annex F of H.323: Single Use Devices. It specifies a simple H.323 voice phone. A future expansion to a simple H.323 text and voice telephone is indicated in this document; the work will build on this document. V.8BIS PROCEDURES FOR H.324 AND V.18 IN MULTI -FUNCTION TERMINALS V.8bis contains unclear statements in sections 10.2.1 and 10.2.2 that can make it give up the V.8bis negotiation on first reception of a V.25 or V.8 signal that may come from a V.8bis-capable device. Such implementations of V.8bis must be avoided. D.153© (A. Farquharson, BT) brings up the question of how to start up the communication when both V.18 and, as an example, H.324 is available in the same terminal and the user can accept the call to be set up with any of them but prefers one. V.8bis is supposed to support function and capability negotiation. V.8 does not, and is therefore unsuitable. But some V.8 or V.25 signals must be transmitted and monitored so that connection also can take place when the other terminal does not support V.8bis. The topic was discussed with Q4/16, which took on the task to straighten up the sections in V.8bis, noting that it is necessary to try once with a V.8bis transaction even if a V.8 or V.25 signal has been received. An interworking guideline for V.8bis was agreed to be completed by Q4/16. V.18 usage of V.8bis is documented in V.18 Appendix 3 (TD-73Corr(PLEN)). TD-25(WP1/16) (A. Farquharson, BT) proposes a new requirement on text telephony for V.18. The network may need to identify when the call is in text mode in order to give network information in text and to offer value added services. Strict use of V.8 and V.8bis signals might be a component to serve that need. The group agreed that the contents of V.18 Appendix 3 that specifies connection procedures for V.18 original, for V.8 and V.8bis first will be issued as a corrected Appendix 3 from this meeting (TD-73Corr(PLEN)), and then will be made normative in the next revision of V.18. V.250 DTE CONTROL OVER V.18 D.211© (R. Brandt, USA) suggests two modifications to the DTE control commands for V.18 as specified in V.250. This request and a comment in TD-22(WP1/16) (G. Hellström, Q9/16 Rapporteur) was considered in a joint meeting with Q7/16.
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• Enter a command that starts probing. This was regarded as against the procedures and introduces a risk of connection in the wrong mode if it is used in the general case when answering, but can be of interest in a case when the V.18 already has been in the automode monitoring state and the user wants to test if there is a text phone at the other end. Therefore, the proposal was accepted with the addition that it must be made clear which of the +MV18S commands have immediate action and which are only mode-setting to influence the action of the A and D commands. • Command for modifying probe message. This is already in V.250, under the name of “+MV18AM
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normative annexes, so that at any time the Recommendation can be refined by adding other networks parameters as they become available. It was emphasized that the network model already has been revised in the US and a new contribution will be prepared for a future Q10/16 meeting. At any rate, D.170© shall be treated as a working text for drafting a new Recommendation on PCM modem testing. Q11/16 WP2, CIRCUIT SWITCHED NETWORK (CSN) MULTIMEDIA SYSTEMS AND TERMINALS The Q11/16 Rapporteur is T. Geary (Rockwell International, USA). TD-7(PLEN) provides the Q11/16 status at the start of this meeting. Q11/16 plans two interim Rapporteur meetings: November 17-20, 1998, in Torino, Italy (joint meeting with Q12, 13 and 14/16); and February 23-26, 1999 in New Jersey (joint meeting with Q12, 13, 14, and 15/16). Q11/16’s informal e-mail reflector is [email protected]. The Q11/16 meeting report is TD- 86(WP2/16). The following two Recommendations were Decided at the SG16 opening plenary: • H.226 (H.multi-link), COM16-62 • H.324 Annex Fv2 (multilink operation), COM16-61 H.320 SYSTEMS: H.263V2 IN H.320 To support H.263v2 (video codec) in the H.320 series Recommendations, the following revisions were Determined by SG16: Recommendation Original TD Final TD H.320 revised, Narrow band visual telephone systems and TD-34 TD-21 terminal equipment (WP2/16) (PLEN) H.221 revised, Frame structure for a 64 to 1920 kbit/s channel in TD-35 TD-23 audiovisual teleservices (WP2/16) (PLEN) H.230 revised, Frame-synchronous control and indication signals TD-36 TD-20 for audiovisual systems (WP2/16) (PLEN) H.242 revised, System for establishing communication between TD-37 TD-22 audiovisual terminals using digital channels up to 2 Mbit/s (WP2/16) (PLEN)
OTHER H.320 SYSTEM ACTIVITY : ADDITION OF T.140 (T.CHAT) TO H.320 It was suggested by the Q9/16 Rapporteur that T.140 be included in the current revision of H.320. An ad hoc was established to review the magnitude of this change and advise Q11/16 of the practicality of making this addition at this time. This group recommended the addition of a code point to H.224 (A Real Time Control for Simplex Applications using the H.221 LSD/HSD/MLP Channels). Contributions are expected at subsequent meetings. It was noted that a reference may be needed in the current revision of H.320 to the effect that support for T.140 is under study. H.324 SYSTEMS/MUX/MOBILE H.324 Implementors Guide TD-59(WP2/16), H.324 Implementors Guide in support of Annex D, Supplementary Services (T. Geary, Q11/16 Rapporteur), was reviewed and approved (as TD-29(PLEN)). H.223 Annex D Optional multiplexing protocol for low bit-rate multimedia mobile communications over high error rate channels TD-41(WP2/16), Draft H.223 Annex D (H. Tanaka, Toshiba, editor), was reviewed and approved. The final text for the Annex appears in TD-37(PLEN). It was noted that this would require signaling in H.245; an ad hoc was established to define the needed code points. They were reviewed and approved by the joint Q11-14 meeting. These additions appear in TD-37(PLEN), issued by the H.245v5 editor on behalf of the Q14/16 Rapporteur. H.223 Annex C Multiplexing protocol for low bit-rate multimedia mobile communications over high error rate channels D.166© (T. Kawahara, Japan) presents a number of editorial errors noted in files for H.223 Annex C, 36_e_64824.doc and td55.doc. The group obtained the latest text for H.223 Annex C from the TSB. Some of the noted errors still existed so an ad hoc was set up to prepare a corrigendum or H.223 Implementer’s Guide. The group
16 Vol. 9.8 Copyright © CSR 1998 November-December 1998 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS reported that three of the sixteen items noted as editorial were agreed to be changed before H.223 Annex C is published. The group recommended that the remaining thirteen editorial items plus the two clarification items be included in an H.223 Implementer’s Guide (issued as TD-41(PLEN)). MPEG-4 in H.324 D.206© (Y. Kikuchi, T. Kawahara, Japan) proposes changes and additions to H.245v5 in support of ISO 14496 (MPEG-4). TD-22(GEN) is a liaison from MPEG to SG16 (it supersedes TD-10(GEN)). There was general discussion on the proposal. Upon review of the proposed H.245v5 code points, it was agreed that IS14496VisualProileAndLevel will be changed to “::CHOICE” - (was “::SEQUENCE”). With this change and the clarification that this would be added to H.245v5, the group accepted the proposal of D.206©. TD-28(PLEN) is the proposed revision. Q11/16 requested that Q14/16 add this functionality to proposed draft text for H.245v5. The Senior Editor of H.245 and proponent of D.217© (Object Oriented Approach to H.245 Extension, P. Cordell, BT), and the proponents of D.206© agreed to use the signaling defined in D.206© as a test case for the D.217© proposal and report the progress to the joint Q11-Q14 meeting. Mobile Terminals for IMT-2000 D.163© (B. Wimmer, Siemens) proposes use of H.324/M terminals for IMT-2000. Participants asked if this was to be the only terminal identified for use in IMT-2000; it was stated that the proposal was not mandating H.324/M. Further work was called for on assessing and enhancing the capabilities of H.324/M mobile terminals. In particular there is a need for a good simulator of the H.324/M mobile mux. This work will continue in Q11/16 and further contributions are solicited. It was noted that TD-05(WP2/16), liaison from TG8/1 on suitability of H.323 protocols for mobile services based on IP, also addresses this issue; it will be coordinated in the joint Q11-Q14 meetings. It was agreed that a liaison to ITU-R TG8/1 ad SG11 were in order; this liaison is TD-72(WP2/16). JOINT Q11, Q12, Q13, Q14 AND Q15/16 The status of the H.263++ video codec work was reviewed with Q15/16. There was agreement that the next versions of video codecs should represent significant improvement over H.263v2 before they are standardized. The work should focus mainly on maintenance of current Recommendations rather than development of new Recommendations. Revision of H.245 (version 5) The group reviewed the intended inputs from Q11/16 regarding addition of signaling for proposed H.223 Annex D and inclusion of MPEG-4 Visual Standard in H.324 as it will appear in H.245v5. The group agreed with the work. The Senior Editor for H.245 noted that the work in support of including MPEG-4 Visual Standard signaling in H.245v5 had revealed that more work may be required on D.217© (Object Oriented Approach to H.245 Extension, P. Cordell, BT); he recommended that D.217© not be included in H.245v4. It was agreed that the code points supporting MPEG-4 Visual Standard in H.245v5 would appear in ASN.1 notation for the purposes of approval at this meeting. Q11/16 AD-HOC GROUPS Q11/16 plans to continue the following ad-hoc groups: Committee Name Chairperson System/H.324 & H.320 M. Nasiri, Ericsson, Sweden Mobile B. Wimmer, Siemens, Germany Non-Conversational Services C. Quist, KPN, Netherlands H.263+ in H.320 Terminals S. Gupta, VTEL, USA Interoperability Experiments (for H.324M Mobile Terminals) M. Luomi, Nokia, Finland TD-17(WP2/16), Comments on MPEG-4 DMIF (Delivery Multimedia Integration Framework) is a liaison from MPEG. In response to a liaison from SG16 which raised concerns about the “architectural mixing” of H.323 and DMIF, MPEG has decided to remove all H series text from DMIF. Then DMIF will interact directly with ATM and IP and use its default signaling for all aspects related to end-to-end control. Q12/16 WP2, B-ISDN MULTIMEDIA SYSTEMS AND TERMINALS The Q12/16 Rapporteur is S. Okubo (Telecommunications Advancement Organization of Japan). TD- 47(WP2/16) is the meeting agenda. TD-27(WP2/16) is the Q12/16 status report at the start of this meeting. TD-28(WP2/16) is the report from the two interim Rapporteur meetings. K. Sakai (Fujitsu) was the Acting Rapporteur during the final plenary sessions of WP2/16 and SG16. Q12/16 will meet twice before the next SG16
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meeting jointly with Q11/16, Q13/16, Q14/16 (and possibly Q15/16): November 17-20, 1998, Torino, Italy, and February 23-26, 1999, New Jersey, USA. TD-77(WP2/16) is the Q12/16 meeting report. DRAFT RECOMMENDATIONS FOR APPROVAL The following three Recommendations were approved (Decided) by SG16: • H.222.0|ISO/IEC 13818-1 Amendment 5: COM 16-67,Information Technology - Generic Coding of Moving Pictures and Associated Audio Information: Systems • H.310 Version 2: COM 16-68, Broadband audiovisual communications systems and terminals, with correction of typographical errors in TD-15(PLEN) (same as TD-18(WP2/16)) • H.247 (H.bmultipoint): COM 16-69 DRAFT RECOMMENDATIONS FOR DETERMINATION TD-26(WP2/16), draft H.222.0|ISO/IEC 13818-1 Amendment 6, was Determined as TD-30(PLEN). This amendment adds the splice parameters for 4:2:2 Profile @ High level and the buffer model for AAC (Advanced Audio Coding) audio. It supports synchronized approval between ITU-T and ISO/IEC JTC1. MPEG PACKETIZATION STUDY TD-39(WP2/16), Study on MPEG Stream Packetization (S. Okubo, Q12/16 Rapporteur), was recognized at the Cannes meeting in June 1998. This document gives some information regarding the media packetization work by other groups. In the IETF: RFC2250 RTP payload format for MPEG1/MPEG2 video and RFC2343 RTP payload format for bundled MPEG” (MPEG-2 video and audio in a packet). DAVIC is currently working on IP-based au- diovisual systems whose specification are planned to be fixed in December 1998 as DAVIC 1.5. DAVIC 1.0-1.4 address ATM and other QoS guaranteed networks. The Rapporteur encouraged members to provide further information of relevant activities outside SG16 and to discuss objectives of and requirements for this study. Related to this topic, two different formats for MPEG-2 storage were mentioned: ATM Forum and Bellcore specifications. Exact information is to be obtained; distinction between storage and transmission formats may be necessary. CLOCK SOURCE CONTROL TD-10(WP2/16), DSS2 protocol provision for carriage of adaptive timing recovery used for transmit (TX) clock information in the support of AAL5 carriage of voice, is a liaison from SG11-WP1/11-Q20. Q12/16 agreed to accept the use of Broadband Report Type IE instead of Notification Indicator IE for controlling transmission clock source, and confirmed that one way indication is sufficient without the need of acknowledgment. Q12/16 will issue an H.321 Implementers Guide to resolve the forward referencing as agreed at the last SG16 meeting in January - February 1998. As H.310 refers to Annex C/H.321 in this respect, it requires no action. Q12/16 reviewed the proposed text for Annex to Q.2931, comparing it with the corresponding wording in H.321, and produced suggested changes. It also recognized that specific code value for inclusion in the Implementors Guide are needed. TD-78(WP2/16) is a liaison reply to SG11 regarding the transmit clock. END STATION IDENTIFIERS OF H.310 AND H.321 TD-11(WP2/16) is a Reply from SG11 to a liaison from Q12/16 on H.310 and H.321 End Station Identifiers in DSS2 draft Recommendation Q2941.2. Q12/16 welcomed the definition of End Station Identifier in projected Q2941.2. TD-79(WP2/16) is the liaison reply providing the exact references to H.321 and H.310 and a brief description of the End Station Identified for Clause 5.2 as requested. FUTURE DIRECTIONS Q12/16 reviewed the current situation which indicates reduced interest in ATM-based systems, and felt that initiation of new study items needed input based on implementation of the basic set of Recommendations (H.310, H.321, H.247). However, incremental improvements to existing Recommendations are always welcome. Broadband supplementary services were mentioned as a possible future work item.
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At the joint Q11-14 session, the need for a study on the future system was identified. The future system may be built on any network and converge current H-series systems and terminals. This discussion was a continuation of the one opened at the previous SG16 meeting in January - February 1998. Q13/16 WP2, PACKET SWITCHED MULTIMEDIA SYSTEMS AND TERMINALS The Q13/16 Rapporteur is D. Skran (Ascend Communications, USA). TD-58(WP2/16) is the meeting agenda. TD-54(WP2/16) is the Q13/16 status report at the beginning of this meeting. TD-66(PLEN), the WP2/16 report, includes the report of this meeting. Q13/16 will meet twice before the next SG16 meeting jointly with Q11/16, Q12/16, Q14/16 (and possibly Q15/16): November 17-20, 1998, Torino, Italy, and February 23-26, 1999, New Jersey, USA. REPORTS/LIAISONS An ATM Forum report was given by F. Audet (Nortel, US). It noted that the ATMF did not want to request modifications of H.245, and that they are focused on mixed environments (IP to ATM to IP). They requested clarification on deadlines for input, i.e., if H.245 will be Determined in April 1999. J. Ott (Teles) reported on the IETF. He will prepare a simple list of areas of overlap/ cooperation so that Q13/16 can focus on issues. TD-29(GEN) (J. Magill, Lucent WP1 Chair) provides a catalog of the standards work in each organization involved in multimedia over IP (TIPHON, IETF, ISO/IEC, ATM Forum, DAVIC, IMTC, ECMA and other ITU SGs). TD-93(WP2/16) from the Rapporteur provides details on areas of overlap or complementary interest between Q13/16 and the IETF, noting the following working groups: MMUSIC, IPTEL, PINT, AVT (audio-visual transport) and two BOFs (“pre Working Groups”) SS7 and E.164. J. Ott was approved as the liaison rapporteur to the IETF. TD-14(GEN) is a liaison from SG15 regarding multimedia on ADSL. Q13/16 has decided to study the operation of H.323 over xDSL and cable modems; TD-62(WP2/16) is a reply liaison. Contributions on this topic are solicited. TD-18(GEN), Voice over IP Voice Quality (Nortel), is a liaison from Q18/12 providing E-model predicted voice quality. The short haul case (Internet now typical, end-to-end delay 200 ms and 2% packet loss) voice quality is es- timated to be less than 70% Good-or-Better (high dissatisfaction). The equivalent future case (end-to-end delay 70 ms and 0% packet loss) voice quality is estimated to be less than 90% Good-or-Better (some dissatisfaction). The E- model (voice quality estimation model) appears as G.107 from SG12. The attention of the delegates was called to this document as it is especially relevant to H.323. TD-5(WP2/16), Liaison Response on the Suitability of H.323 Terminals for Mobile Devices Based on IP, is from Task Group 8/1. TD-1(WP2/16), another liaison from TG8/1 on support of Mobile Multimedia services by IMT-2000, is related, but with H.324 substituted for H.323. This led to a debate between the advocates of H.323 (and IP systems) vs. H.324 (and frame systems). Matters of efficiency and robustness were key in this discussion. TD-72(WP2/16) is the reply liaison, requesting information on the expected bit rate(s); it indicates that Q13/16, with the bit rate information, will study the issues and provide a report hopefully in time for the TG8/1 meeting which ends November 20. The report will include QoS, BER, bit rate, delay requirements, etc., and sharing of cells with other applications. TD-14(WP2/16), Proposal on GII Responsibilities regarding Integrated Management of Telecom Networks and IP Networks, is from SG4. A liaison will be prepared indicating that IP is managed via SNMP. The goal of unified management is important, but recognition of the existing SNMP must be recognized and they must interwork/manage it, including Q14/16 MIB work. TD-80(WP2/16) is the reply, sent jointly with Q11/Q12/Q13/Q14. H.323 IMPLEMENTERS GUIDE Changes to H.323, H.255.0, H.235, and H.450.x recommendations are all included in a single implementers guide so that implementors need look in only one place for all corrections to documents related to H.323. TD-6(WP2/16), Draft H.323 Implementors Guide V2 (J. Toga, Intel, Editor) was presented; it was noted that the ICV (Integrity Check Value) issue is unresolved and will not be included in this revision of the Implementors Guide. An intervention called attention to some additional concerns related to Master/Slave determinations. These will be considered for the next version of the implementors guide as consensus did not exist that the solution suggested was the correct one.
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Another issue was raised concerning the need to clarify that multiple call proceedings can be sent (or not). It should be clarified that call proceeding can only be sent once in “pure (non-H.323)” Q.931. It was agreed that the usage of proceeding for fast start was a mistake, and Facility should be used. This will be put in the implementors guide with a note that the usage of proceeding was simply an error if it is used in the case where proceeding has already been sent. Fast Start will be added to the Facility message ASN.1. A further issue was raised on how long one should wait for a Fast Start element to get back to them. This was added to the implementors guide. It was mentioned that section 8.1.7 on the refusal of fast start was ambiguous. It was agreed that the Fast Start element is not in any and ALL messages. Further clarifications arose out of the Annex E (Call Connection over UDP) /Annex F (single use device) work; they are described in TD-91(WP2/16), and will be put toward the next version of the implementors guide. The H.323 Implementors Guide was approved as it appears in TD-60(PLEN). D.187© (T. Taylor, Canada) is a Clarification of H.323 Call Takedown Procedures. It notes three problems. 1. Clearing of Call Signaling Channel by Gatekeeper: D.187© proposes to require that V3 Gatekeepers keep the channel open, or to send a new ReleaseCompleteReason to cover the situation when the channel is closed; neither proposal was accepted. It was agreed that additional text needs to be added to say that the channel can be re-opened later. 2. Race Condition During Call Takedown: the point was accepted; Editor G. Thom (Delta Information Systems) will work with V. Kumar (Intel) to include it in the Implementors Guide. 3. Proper Cleardown at the Transport Level: D.187© proposes a more graceful closing of TCP. Q13/16 will add to the implementors guide a reference to the appropriate RFC and a recommendation to use “graceful” shutdown rather than “Abort.” TD-60(WP2/16) (H.225 editor, G. Freundlich, Lucent) contains 14 editorial changes and minor corrections to the H.323v2 Implementer’s Guide. Each point was addressed, requiring multiple changes to the implementors guide draft. H.332 H.332 (ex H.loosely coupled) was approved by the SG16 Plenary as COM-16-41 plus the single change (Session Description Protocol is RFC2327) in TD-14(PLEN). H.332 had not been Decided at the previous SG16 meeting as the RFC number to reference was not available. H.323 ANNEX D FOR REAL TIME FAX H.323 Annex D was presented as COM-16-60; various editorial changes were agreed. H.323 Annex D uses H.323 procedures to transfer T.38 (real time fax) packets. T.38 Annex B describes a T.38-only-capable terminal that supports a subset of H.245 messages using H.245 tunneling. However, the T.38 Annex B terminal can interwork with an H.323 Annex D terminal using the H.323 Fast Connect (8.1.7) and Encapsulation of H.245 messages in Q.931 messages (8.2.1) procedures. H.323 Annex D was approved at the SG16 plenary. The changes appear as TD- 70(WP2/16). The changes to be applied to COM-16-60 appear in TD-54(PLEN). TD-4(WP2/16), Liaison to SG16 on Draft Annex D to H.323, is from SG8. It presents a range of issues for resolution. The reply liaison is in TD-92(WP2/16), which was sent with the final text of H.323 Annex D attached. Although some complex issues were raised, TD-92(WP2/16) documents a compromise satisfactory to all. D.159© (D. Duehren, Brooktrout, US) proposes revisions to draft H.323 Annex D to Support T.38. The following were agreed: • In the H.323 options section, a reference would be added to T.38. • With regard to DTMF, RTP DTMF is removed, and will require tunneled H.245 in H.323 Annex D. This will also have to be done in T.38 Annex B. • It appears that the maxBitRate text from the previous liaison was lost by accident; the editor will add it back in. • The editor will adopt other changes such as removal of references to T.38 voice.
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D.212© (Eight Japanese companies) proposes Corrections to H.323 Annex D. The changes were accepted; the editor will make appropriate changes to indicate that the things specified (RTP/DTMF, non-fast start) don’t apply to interworking with T.38. D.213© (Eight Japanese companies) proposes TCP Support on H.323 Annex D. This document calls for TCP to be mandatory, with UDP optional, and makes suggestions for when each should be used. A compromise was adopted where TCP is mandatory in H.323 Annex D and UDP may be used as described in T.38.
H.263+ (H.225.0 ANNEX I ) H.263+ VIDEO PACKETIZATION COM 16-70, H.225.0 Annex I, describes an RTP payload format for video data encoded according to the H.263v2 (H.263+). This was approved without change. H.323 ANNEX F “SINGLE USE TERMINAL” TD-48(WP2/16) (J. Ott, Teles) is Draft H.323 Annex F, “Single Use Devices.” This document defines in particular Single Use Audio Devices that operate using H.323 protocols (are interoperable with H.323v2 devices) and are well suited for IP telephony applications. A number of changes were made including: • Fax is explicitly a possible future SUD • RTP DTMF was removed and H.245 tunneling inserted instead • H.323v3 will be modified to require support for Audio SUDs in MCUs and Gateways. TD-31(PLEN) is the initial text. It was reviewed and replaced by TD-51(PLEN). This Annex was Determined. H.323 ANNEX E “CONNECTION OVER UDP” TD-46(WP2/16) (D. Gurle, VocalTec, editor) is H.323 Annex E, “Call Connection over UDP.” H.323v2 introduces the concept of Fast Connect which allows media cut-through in as little as two round-trips from callee to caller (including TCP messages) and in 2.5 round-trips from caller to callee. Using UDP instead of TCP, this can be reduced to one round-trip and 1.5 round-trips, respectively. By adding slightly to the call setup procedure over UDP, a full range of call-signalling messages may be supported. This is especially important when using the Gatekeeper- Routed-Model. It was reviewed, aligned with related work and modified. The first revision text appears in TD- 19(PLEN). It was decided to put this document forward for Determination after further work. It was agreed that Section E.5 (specifics) would be an informative appendix and that new text would be provided prior to Decision. The final text for Determination appears as TD-47(PLEN). It was Determined. H.225.0V3 ANNEX G (GK TO GK COMMUNICATIONS) TD-42(WP2/16) (G. Freundlich, Lucent, Editor) is Draft H.255.0 Annex G - GK to GK Communication. This Annex describes communications between administrative domains in H.323 systems for the purpose of completing calls between the administrative domains. An administrative domain exposes itself to other administrative domains through a border, or edge, element. Annex G does not require an administrative domain to reveal details about its organization or architecture. Annex G does not mandate a specific system architecture within an administrative domain. Annex G supports the use of any call model (gatekeeper routed or direct endpoint). An extensive discussion was held and the following agreements reached:. a) It is a requirement to provide the endpoint type information to the caller, but this must be done in a scalable fashion, i.e., with some roll-up of endpoint type as in “here are 360,000 endpoints, they are all voice only.” Concern was expressed about duplicate listings of the same endpoint as a scaling problem. b) There will be push procedures, and they will be added using the Zone Update. These procedures will cover size of packets, number of templates that can be sent, and frequency of such updates. c) There are 3 kinds of mobility i) IP mobility – this will just happen, and is compatible with Annex G ii) H.323 address mobility – this may require some scheme of home GKs/foreign GKs iii) home environment mobility (future definition) [IP home environment & H.323 home environment] There is no need to make H.323 mobility a part of this determination. d) It is OK to call the zone request a zone request even though it sometimes does not describe a real zone. e) The scope of the document should reflect the requirements more but not limit the scope for all time. The focus of the scope is on address resolution. This would affect the title “Inter-Domain Relationships.”
November-December 1998 Vol. 9.8 Copyright © CSR 1998 21 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS f) Signaling is really in H.246. g) Multi-casting for usage with the inter-domain protocols will be reviewed. This will be an option, as SLP (Service Location Protocol) is not very mature in the IETF. Multi-cast will be added as “for further study” and also based on proposals at the next experts’ meeting. i) The protocol is based on “rollup” and thus assumes non-random distribution. Thus, it is not reasonable to have “complete” freedom of number assignment in a non-clearinghouse environment. Of course, a universal number space can be provided by a clearing house, but this leads to issues related to the control of the clearing house. Thus the protocol will support both a fully flexible number scheme and non-fully flexible numbering scheme as chosen by the service provider. j) It was agreed to proceed with Annex G as SLP will not be sufficiently timely. k) Requirements for inter-zone i) predictable encoding size (not true for ASN.1) ii) very compact There were three proposals: i) templates in BER, with binary wrapper ii) binary wrapper, octet strings for templates iii) wrapper in BER, octet strings for templates The agreement is to propose that one of these three be chosen at the November experts’ meeting based on inputs. The protocol will be specified in ASN.1, then converted as needed when the white paper is issued. l) Future development of this annex will consider intra-domain (or GK to GK) communications and further develop this, either as part of this annex or as a new annex. The work may include specification of interface B (border element to gatekeeper) in Figure 1. D.164©, InterGK Communications with Distributed GK Architecture of Multiple Zones (R. Roy, AT&T), presents a method of extending H.323 to do address routing and caching. Text for Determination appears as TD-82(WP2), with a final version Determined as TD-61(PLEN). H.450.X IMPLEMENTORS GUIDE D.214 (Japan) provides editorial comments on Rec. H.450.1 (Generic Functional Protocol, QSIG based), H.450.2 (Call Transfer), and H.450.3 (Call Diversion). All of these comments were accepted and will be put in the Implementors Guide, for version 2 of these Recommendations. H.450.4 (CALL HOLD) TD-49(WP2/16), “Call Hold Supplementary Service for H.323” (M. Korpi, Editor), notes that it appears that music on hold was always supplied; the text will be changed to indicate that music/video on hold may be supplied, but is not required. A number of other editorial comments were accepted. TD-34(PLEN) is the final text as Determined by SG16. H.450.5 (CALL PARK AND CALL PICKUP) TD-50(WP2/16) (M. Korpi, Editor) is draft Rec. H.450.5, Call Park and Call Pickup Supplementary Services for H.323. A number of changes were made. TD-35(PLEN) is the Determined text. H.450.6 (CALL WAITING) TD-51(WP2/16) (M. Korpi, Editor) is H.450.6, Call Waiting Supplementary Service for H.323. In section 5/7.1.1, mention is made of a subscription option; this needs to be explained as a local terminal configuration matter. G. Freundlich pointed out that if the GK knows that endpoint B does not provide supplementary services, the GK can provide the indications on the endpoint’s behalf; this will be added to section 7.3. These and other changes were made; TD-36(PLEN) is the Determined text.
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H.450.7(MESSAGE WAITING) TD-52(WP2/16) is H.450.7, Message Waiting Indication Supplementary Service for H.323. In section 7.5, procedures when the GK is not available to cache the messages need to be described. There are not any new messages needed, but some text was added. TD-40(PLEN) is the Determined text. H.450.8 (CALL IDENTIFICATION) TD-53(WP2/16) (G. Freundlich, Lucent, editor) is H.450.CallID, Call Identification Services for H.323. A discussion ensued, where it was held that not all of these features should be in H.450.x, and that perhaps this work should be split, with the number identification being part of the basic call, and the name being an H.450.x supplementary service. This work will continue toward modification of H.255.0v3, with focus on full ISDN transparency across H.323 networks. H.323 ANNEX I (H.323 OVER N-ISDN) D.171© (J.P. Blin, France Telecom) proposes H.323 draft Annex I, Point-to-Point H.323 Over ISDN. D.173© (J.P. Blin, France Telecom) proposes requirements for using H.323 on ISDN. See also the Q14/16 report below. The position of PictureTel was that H.323 terminals on ISDN should have a mandatory H.320 fall-back mode. The view was expressed that H.323 could and should be used over all network types. The main issue seemed to be whether it was necessary to standardize Annex I. Q13/16 considered this vision of universal usage of H.323, and breaking with H.320 over a period of time. It was suggested that this long term vision be considered part of the future work, especially toward a joint project for Questions 11, 12, 13, and 14/16. Among the ideas suggested for part of this work were: • A common upper layer, such as H.245, with different lower layers, perhaps as options. • A common core for all parts of the protocol that is tightly packed and can work well at a low bit rate, but with a set of layers that add quality up to much higher bit rates. This might include: – A layered audio coder – A layered video coder (possibly H.263+) – A layered control system The key idea in this approach is rather than creating a series of systems targeted at different transports, instead a single system would be designed to work over all transport systems and bit rates, including xDSL and cable modems. This work might replace or become H.24L. Although general enthusiasm was expressed for this idea, and it will be added to the work program, some voices urged caution given the number of new terminals that have been introduced by the ITU-T over the last five years. Contributions on this topic are solicited. The Q11/12/13/14 rapporteurs met with S. Campos Neto (WP3/16 chair) on this topic (layered audio/video coders) and conveyed the desire of the relevant Questions to work with WP3 on this new project. Annex I of H.323 was not brought forward for Determination due to the lack of consensus. D.156©, Comments on the Projected Annex/Appendix for H.323 over N-ISDN (H. Harasaki, NEC), examines the various options for interworking among current H.323 terminal types. H.323V3 D.160© (USA) proposes the study of highly available H.323 networks. That is, how can H.323 networks recover when a gatekeeper and gateway (possibly supporting many active calls) fails. It was agreed that considerations of reliability, load balancing, and duplication are within the scope of Q13/16 insofar as they are reflected in the protocol itself. The rapporteur cautioned that although this was a worthy goal for H.323v3, the protocol should not become too burdensome, especially on a simple endpoint. TD-8(WP2/16), Use of High Layer Information (HLI) Information Element (SG11/Q20) seeks to correct the usage in H.323 Annex C of the BHLI (Broadband HLI), and contains a proposal for using the Generic identifier transport (GIT) information element. It was agreed that using the GIT was the appropriate way forward, but that a “pre-GIT” ATM system would require some special methods such as user-to-user information. This change will be made in H.323v3 and in the H.323 implementors guide. H.323v2 to H.323v3 interoperability will have to be taken into account. The new text will be sent to SG11 and the ATM Forum. TD-76(WP2/16) is the proposed reply liaison. This was re-written; TD-88(WP2/16) is the final liaison.
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TD-31(WP2/16), H.323 Media Transport over ATM (P.A. Probst, ATM Forum), contains a proposal for a new ATM Forum recommendation for carrying H.323 over ATM networks, especially in the context of IP to ATM to IP networks. It proposes a new type of gateway, an H.323 to H.323 “gateway” which does not affect the media stream, but does affect the control stream. It was noted that Figure 2-2 is very similar to Annex C, and could be adopted into Annex C. It is the intent of Q13/16 to adopt some of these ideas to enhanced Annex C to H.323v3. TD- 87(WP2/16) is the response to the ATM Forum. TD-39(WP2/16) is a report from Q12/16 Rapporteur S. Okubo on efforts related to MPEG2 packetization, and also to multiplexing audio/ video in the same packet. This report covers the work of DAVIC, the IETF, and other groups. The need to evaluate the quality/focus on the existing IETF RFCs was mentioned as a major goal of this work. See also the Q12/16 report above for additional information. TOPICS FOR FUTURE WORK TD-31(GEN), Proposal to specify H.323 text conversation terminal (G. Hellström, Q9/16 Rapporteur), requests that Q13/16 take up the SUD (single use devices) (and non-SUD) H.323 text conversation terminal work as a follow-on to Annex F. The work will be taken up and contributions are solicited. Q14/16 WP2, COMMON PROTOCOLS, MCUS AND PROTOCOLS FOR INTERWORKING WITH H.300- SERIES TERMINALS
The Q14/16 Rapporteur is G. Thom (Delta Information Systems, USA). TD-29(WP2/16) is the Q14/16 status report at the beginning of this meeting. TD-28(WP2/16) is the report of the previous interim rapporteurs meetings. TD-75(WP2/16) is the report of this Q14/16 meeting. Two interim meetings are planned jointly with Q11/16, Q12/16, Q13/16 and Q15/16: November 17-20, 1998, Torino, Italy, and February 23-26, 1999, New Jersey, USA. H.245 VERSION 4 APPROVAL COM16-59 contains H.245v4, Control protocol for multimedia communications. D.217© (P. Cordell, BT) proposes an object oriented approach to H.245 extension. This concept was previously presented in Cannes 8-11 June, 1998 (See APC-1402, CSR-T Vol. 9.5) and was supported. However, it was determined at this meeting that D.217© was not ready to be included in H.245v4 and it should be deferred to H.245v5 (see below). It was agreed that COM16-59 as originally published should be put forward for Decision without the inclusion of D.217©. H.245v4 was approved (Decided) at the SG16 plenary. H.245 VERSION 5 DETERMINATION Q11/16 agreed to incorporate MPEG-4 video as a video codec in H-series terminals. The additions which need to be made to H.245 (originally contained in D.206©, Y. Kikuchi, T. Kawahara, Japan) are in TD-28(PLEN). Q11/16 also approved H.223 Annex D (Optional multiplexing protocol for low bit rate multimedia communication over highly error prone channel) which requires additional support in H.245. These additions are contained in TD- 39(PLEN). D.217©, Object Oriented Capability Sets (P. Cordell, BT) was not ready to be included in H.245v4 for Decision at this meeting. This will be studied during the interim meetings. It was agreed that the current text should be included in H.245v5 for Determination at this meeting. The revised text is in TD-39(PLEN). TD-39(PLEN) plus the additions in TD-28(PLEN) are the text of H.245v5 as Determined at the SG16 plenary. H.341 (H.MEDIAMIB) DETERMINATION TD-55(WP2/16) are the minutes of the H.Multimedia MIB BOF (Management Information Base Birds of a Feather), 8/25/98. Q14/16 discussed the relationship of H.341, Multimedia management information base, and the IETF. The IETF RTP (Real Time Protocol) MIB activities are within the Audio-Video Transport WG. The MIB is on standards track and should go to Last Call for Proposed Standard in 1998 or early 1999. Q14/16 will be able to reference it by RFC #. There was some question as to the best way to progress H.341. There are two approaches to moving forward with H.341: 1. Develop the MIBs in Q14/16 (H.341) and attempt to get technical support from SNMP experts. 2. Have the IETF develop the MIBs and Q14/16 develop H.341 which references them.
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The consensus of the group was to produce the multimedia MIBs in Q14/16, incorporate them in H.341, find SNMP experts in our organizations to review the work and provide technical assistance, and begin to sample implementa- tions to verify the MIB process. This plan was communicated to the IETF in a liaison statement contained in TD- 67(WP2/16). TD-23(WP2/16)©, draft H.341, was presented and discussed. Some editorial changes were identified. It was agreed that it was technically stable, there were no known flaws, and the draft should be moved forward for Determination at this meeting. It was pointed out that as a result of compilation and testing, some of the ASN.1 may change, but the content and structure was stable. H.341 (H.MediaMIB) was Determined by the SG16 plenary as TD-27(PLEN)©. TD-7(WP2/16) is a liaison from SG4 in response to the Q14/16 liaison in TD-28(WP 2/16) Annex 2-4 (report of the interim rapporteurs meetings). This liaison had three points: • SG4 did not have time to review and comment on Q14/16’s MIBs • SG4 notes Q14/16’s use of SNMP and directs Q14/16 to their other liaison on management of IP based networks • SG4 provided information on fitting the multimedia tree into the TMN object identifier. TD-14(WP2/16), TD-5(GEN), TD-6(GEN), and TD-25(GEN), additional liaisons from SG4, were also reviewed. It was agreed that Q14/16 would send them another liaison acknowledging their interest in the management of IP-based networks, informing them of Q14/16’s work in this area, and recommending that they attempt to be interoperable (or at least be compatible) with SNMP. This liaison is contained in TD-80(WP2/16). REMOTE DEVICE CONTROL H.283 (H.RDC), H.282 (V.RDC) AND T.136 (T.RDC) DETERMINATION D.207©, H.282, V.RDC (A. Woollett, ImageCom), and D.208©, T.136, T.RDC (A. Woollett, ImageCom), are drafts of V.RDC (set of services and protocol for RDC) and T.RDC, respectively. T.RDC describes how to utilize V.RDC using T.120 as the lower layer protocol. Future recommendations may describe how to utilize V.RDC using other lower layer protocols. Editorial changes were identified. TD-22(WP2/16) (M. Duckworth, PictureTel) is draft H.283, H.RDC. H.RDC is a data link protocol to carry Common RDC (that part of RDC common to T.120 and H.323) protocol over UDP. The editor was directed to consider the use of the reliable UDP method of H.323 Annex E. If necessary, the method in H.323 Annex E should be extended so that there is a single reliable UDP protocol for use in H.323. Several editorial changes were identified. It was indicated that the use of H.283 in GW to GW communications needs more investigation. This will be indicated as an open issue. It was noted that this draft recommendation was more complete than anticipated. It was agreed that H.283 should be put forward for Determination at this meeting. The revised text, TD-38(PLEN)©, was Determined at the SG16 plenary. The revised text for Determination of H.282 (V.RDC) is contained in TD-24(PLEN) and for T.136 (T.RDC) in TD-25(PLEN). Both were Determined. H.246 ANNEX B (INTERWORKING) There has been little contribution to this work and the editor suggested that Determination be deferred until there is more support for this draft recommendation. This was agreed. TD-12(WP2/16), Liaison from Q11/11 on interoperability of H.series multimedia terminals with voice-only terminals on switched circuit networks, and liaison from Q7/15 on speech quality aspects of internet telephony, were reviewed. TD-12(WP2/16) notes that Q.699 (DSS1/ISUP) provides some interworking descriptions. TD-13(WP2/16) notes that G.131 specifies the relationship between delay and talker echo that is acceptable. In general, an end-to-end one-way delay of 25 ms or more will require echo cancellation. The H.246 editor will take these issues into consideration for further development of Annex B. OTHER H.246 ANNEXES D.171© (J.P. Blin, France Telecom) is draft H.323 Annex I, Point-to-Point H.323 Over ISDN. D.173© (J.P. Blin, France Telecom) provides requirements for using H.323 on ISDN. D.156© (H. Harasaki, NEC) comments on the projected Annex/Appendix for H.323 over N-ISDN. In discussion, it was suggested that Q14/16 develop an Annex to H.246 which defines an H.323 to N-ISDN Gateway (GW) which does not convert to H.320 on the N-ISDN side. This would be used to allow H.323 terminals to connect via N-ISDN through the GW to an IP network. It would also allow efficient GW to GW connection using N-ISDN without the protocol conversion required to go to H.320. It was indicated that these exist today in the form of IP routers. No further action is indicated at this time. See also the Q13/16 report above. TD-31(WP2/16), H.323 Media Transport for ATM (P.A. Probst, ATM Forum), suggests an H.323 to H.323 Annex C (H.323 on ATM) Gateway. It was determined that this was an ATM switch issue. No further action is indicated at this time.
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The following documents were discussed: D.188©, Media Control Aspects of the Proposed Gateway Device Control Protocol D.191©, Signalling Transport Aspects of the Proposed Gateway Device Control Protocol D.192©, Framework for the Proposed Gateway Device Control Protocol V4.2 D.193©, Connection Control Aspects of the Proposed Gateway Device Control Protocol D.194©, Device Management Aspects of the Proposed Gateway Device Control Protocol D.195©, IPDC Base Protocol (all from Nortel, Canada) D.158©, Functional Partitioning of SCN/Packet Gateway (G. Freundlich, Lucent) Many concerns were noted. It was decided that a small group would draft a terms of reference for the Gateway Control Protocol stating the problem to be solved, requirements of a candidate solution, and restrictions on overlap with existing H.323 concepts. The result of this effort, TD-89(WP2/16), Terms of reference for additional study of H.323 gateways interworking with SCN, forms the basis for work on an Annex to H.246. To achieve greater scalability, the H.323 Gateway function may be further decomposed, and sub-functions contained within the H.323 Gateway may be placed in different physical devices. This shows the possible arrangements of sub-functions and the resulting interfaces that may be of interest to standardize. FUTURE TERMINAL TYPE There was a general discussion during the joint Q11/16, Q12/16, Q13/16, and Q14/16 session on the subject of a unifying terminal type which would be applicable to a wide variety of networks with various levels of quality of service. It was suggested that this terminal would use layered coding techniques for the audio, video and control streams. These streams would then be carried on different networks in a manner appropriate for that network and in a way that would enhance interoperability between terminals on different networks. Terms of reference for this work will be developed during the interim rapporteur meetings. Q15/16 WP3, ADVANCED VIDEO CODING The Q15/16 Rapporteur is G. Sullivan (PictureTel/USA). TD-16(WP3/16) is the report of the Q15 Rapporteur’s meeting in Whistler, British Columbia July 21-23, 1998. TD-19(WP3/16) is the status report of Q15/16 activities. TD-17(WP3/16) is the Q15/16 agenda. TD-30(WP3/16) is the Q15/16 report of this meeting. Q15/16 has planned two interim meetings, November 3-6 in Seoul, Korea, and February 23 - 26, 1998 in New Jersey, with Qs 11/16 through 14/16. Q15/16, the video coding area within WP3, currently has two significant ongoing activities, H.263++ and H.26L. The H.263++ development effort is for near-term standardization of enhancements to produce a third version of the H.263 video codec for real-time telecommunication and related non-conversational services. The H.26L development effort identifies new video coding technology beyond the capabilities of incremental enhancements to H.263, for longer-term standardization. In addition to this focus on future needs, Q15/16 is tasked with maintaining the existing prior video coding standards (H.261, H.262, and H.263, and presumably H.120) as necessary. The primary means of document distribution within the Q15/16 Video Coding Experts Group is electronic, and Q15/16 documents are on an ftp site maintained by G. Sullivan of PictureTel: ftp://standard.pictel.com/video-site The group conducts its e-mail conversations over an e-mail reflector that is maintained by M. Zeug of Iterated Systems: [email protected] Requests for subscriptions and “unsubscriptions” for this e-mail reflector should be sent to the list manager: itu-adv- [email protected] H.262, AMENDMENT 5 DETERMINATION H.262, Amendment #5: Draft Amendment 5 (High Level for 4:2:2 Profile) to common text recommendation H.262 | IS 13818-2 (MPEG-2 video), was Determined as TD-26(GEN). JOINT DISCUSSIONS WITH QS 11/16, 12/16, 13/16, AND 14/16 A joint session was held with Q11/16, Q12/16, Q13/16, Q14/16 and Q15/16 to discuss coordination issues. See the Q11, Q12, Q13 and Q14/16 reports for additional information. Common Text Document Handling for H.262 (MPEG-2 video) and H.222.0 (MPEG-2 system) The group discussed the coordination of scheduling of amendments to H.262 and H.222.0 with ISO/IEC JTC1 as addressed in TD-15(GEN), liaison from MPEG, ISO/IEC JTC1/SC29/WG11. A significant delay had been experienced in the publication of the amendments approved at the January/ February SG16 meeting (Amendments 3
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and 4 to H.262 and Amendments 3 and 4 to H.222.0), but it appears that the future work on these recommendations is synchronized well in SG16 and JTC1 (as long as the time between Decision and publication can be kept to a minimum). In particular, Amendment 5 to H.222.0 was Decided (as COM16-67), and Amendment 5 to H.262 and Amendment 6 to H.222.0 were Determined (as TD-26(GEN) and TD-30(PLEN), respectively) at this SG16 meeting. TD-32(GEN) a liaison statement to ISO/IEC JTC1/SC29/WG11 (MPEG) was drafted and approved regarding publication of the common text standards H.222.0 | IS 13818-1 and H.262 | IS 13818-2 (a joint issue for Q12/16 and Q15/16). Q15/16 noted their efforts to facilitate timely publication of updates to these common text standards. Future Work Items The status of the Q15/16 H.263v3 and H.26L projects were discussed, and Q11/16 reported on its plan for an H.32L terminal project with a similar schedule. Q13/16 reported its work on “single use device” specifications in H.323 (not at present including video use). PLANNING AND WORK ON H.263++ The current workplan of the H.263++ project is provided in Annex Q15.A of TD-62(PLEN), the WP3/16 report. Decision is planned for 2002 (see also CSR-T Vol. 9.2 for the work plan). The group discussed the current status of work on H.263++ and recalled the eight key technical areas that appear to be promising for further investigation: 1. Error resilient data partitioning 2. 4x4 motion compensation and DCT 3. Adaptive quantization 4. Reference picture selection enhancement 5. Scalability enhancement 6. IDCT mismatch reduction 7. Deblocking and deringing filters (normative or informative) 8. Error concealment (normative or informative) However, although these areas appear worthwhile for investigation, none of them have appeared to be fully mature yet in terms of having both a sufficiently stable technical content proposal and a high level of proven effectiveness and necessity confirmed by an independent implementation experiment. Thus Q15/16 has not yet created a draft for H.263v3 technical content. PLANNING AND WORK ON H.26L The current workplan of the H.26L project is provided in Annex Q15.A of TD-62(PLEN), the WP3/16 report (see also CSR-T Vol. 9.2 for the work plan). The H.26L project appears to be on track, and will continue to be led by the Q15/16 Associate Rapporteur, K. Hibi. A significant milestone for this project is scheduled for the next Q15/16 Rapporteur’s meeting (Nov. 3-6, Seoul, Korea), at which technical proposals are expected for H.26L. FUTURE WORK Q11/16 has asked to collaborate closely with Q15/16 regarding the use of video communication on mobile networks. Progress is expected at the joint rapporteurs meeting in February 1999. The experts agreed to further consider the needs of video coding for sign language and lip reading communication, and in particular to review TD-35(GEN) provided by the Q9/16 rapporteur. Q16/16 AND Q17/16, MULTIMEDIA HARMONIZATION AND COORDINATION M. Matsumoto (Japan) is the Rapporteur of Q16/16 and Q17/16. T. Taylor (Nortel, Canada) is the assistant Rapporteur. The meeting agenda is TD-27(GEN). The Q16-17/16 meeting report is TD-81(PLEN). LIAISONS Some SG16 Rapporteurs complained that the volume of liaison documents directed to all Questions is excessively large, and liaisons in general require a substantial amount of time. They asked that Q16-17/16 get involved in document management to cut down the volume. TD-2(PLEN) is a request from ITU ICG (Intersector Coordination Group) SAT for a progress report on work related to satellite transmission. The liaison response notes that the only specifically satellite-related work in Study
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Group 16 is the recently Decided (2/98) H.324 Annex E (COM 16-R37), Initialization of acknowledgment timer T401 to allow operation over geostationary satellite channels. Because Working Party 1/16 takes account of channel worst-case characteristics when defining modem operation, the liaison requests that WP1/16 be informed if any new Recommendation modifies satellite transmission channel characteristics. TD-8(PLEN) (TSAG) is a description of procedures for coordination between the ITU-T and the IETF. It requires that Study Group 16 appoint one or more official contact persons to the IETF and notify the ISOC Vice President of Standards accordingly. J. Ott (Teles) and T. Taylor (Nortel) were nominated as contact points for SG16. TD-10(PLEN) is a TSAG contribution on interoperability testing. The nature of the desired response to this document was unclear and remains an open item. The document is related to GII project F.4 (see below). A New Joint Task Group On Multimedia Broadcast Evolution and Common Content Format has been established. SG16 will be asked to appoint a liaison officer to represent the Study Group on this Joint Task Group. THE NATURE OF Q16-17/16’S COORDINATION TASK Discussion resulted in enumeration of the aspects of the coordination task. It was noted that Q16-17/16 has two generic mechanisms for coordination: the framework Recommendation H.200, which must be revised to make it current, and the summaries of work status prepared by the Secretariat. PROMOTION OF THE WORK DONE ON MULTIMEDIA COMMUNICATIONS TD-28(GEN) (I. Sebestyen, Associate Q16-Q17/16 Rapporteur) recalls previous measures put in place to advertise the work of SG16, and notes that no contributions have been received for this purpose. Concern was expressed that MPEG-4 in particular is promoting its product far more vigorously than SG16. It was noted that, at the January meeting, each Working Party had prepared such a contribution describing the results of its work, but this material has apparently disappeared. The question of appropriate procedures for authorization of press releases was raised. Any press release should be made by agreement of the SG16 management team. REVISED SG16 SEMINAR ON MULTIMEDIA Chile has proposed that the spring, 1999 meeting of Study Group 16 be held at the University of Chile in Santiago. Because of the timing of the school year, space would be available only in the middle of May. The Study Group would have to assess whether the University’s facilities would meet the requirements for the meeting. The SG16 Chairman had proposed that a seminar on multimedia be held in conjunction with the meeting. M. Matsumoto (Q16-17/16 Rapporteur) has been working on details of this proposal, and presented them. The seminar would be held on World-Wide Telecommunications Day, 17 May 1999, with the Study Group meeting starting on the following day. The meeting generally approved M. Matsumoto’s proposals as the basis for further work. GLOBAL INFORMATION INFRASTRUCTURE (GII) PROJECTS TD-24(GEN) from JRG (Joint Rapporteur Group) on GII, July 20-24, 1998, Geneva, is the report on the third meeting of the JRG on GII. This includes reports on both the PINT and TIPHON activities. TD-5(PLEN) from Y. Robin-Champigneul as SG16 liaison on JRG/GII and TD-2(GEN) from SG13 are liaisons received on the GII project. SG13, the lead SG on GII, at their plenary meeting in June produced three Recommendations Y.100 (GII: General overview), Y.110 (GII: Principals and framework architecture), and Y.120 GII: Scenario methodology. Y.110 defines four GII blocks, GII service packaging and cooperation service compo- nents, Middleware support components, Application/service creation support and GII interworking service components. Table 4 notes the accepted proposals from SG16 to participate in the GII projects. GII Project name Project leader Collaborating Bodies project No. F.3 Information appliance SG16 (Q2, 11, 12, 13, 17) SG8 (Q1, 3, 4), SG9 (Q17, 19, 20, T. Taylor 24, 25, 27, 28), DAVIC, IEC TC100, JTC1
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F.4 End-to-end SG16 (Q1, 2, 3, 12, 13, 14, 15, SG8 (Q4, 6, 7, 9), SG9 (Q19, 24, interoperability 16, 17, 18) 29), SG12 (Q16, 18, 21) DAVIC, M. Matsumoto IEC TC 100, JTC1 I.1 IP and SG13 (SG11, 16 & IETF will SG2, 3, 7, 9, 10, 11, 12, 15, 16, telecommunications lead the development of the IETF, W3C, JTC1, ATM Forum, networks resulting protocols.) M. DAVIC, TIPHON interrelationships Vandenameele, C.S. Lee I.2 Multimedia over IP SG16 J. Magill SG2, 3, 7, 8, 9, 10, 11, 12(Q16, 18, 21), 13, 15, JTC1, IETF, IMTC, TIPHON, DAVIC M.3 Technical framework for SG16 (Q1 + tbd) SG13 electronic commerce M.4 Middleware for SG16 (Q16, 17) SG7(Q24), SG10, OMG, TINA-C, multimedia M. Blaschitz DAVIC, Open Group Table 4. SG16 Participation in GII Projects Project I.2, Multimedia Over IP The GII project I.2 (TD-29(GEN), Review of Multimedia over IP Standards, J. Magill, WP1/16 chair) reports findings on IP-related work in progress in a number of standards bodies. It was not clear what, if any, additional work should be done under project I.2. See the Q13/16 report above for additional details. Project M.4, Middleware For Multimedia The key point in this project collaboration is that Study Group 16 has the view of the end-to-end services to be provided. Study Group 10 is responsible for the network operating system which will support the implementation of those services. See Q216 report above for details. Project F.4, End-To-End Interoperability TD-21(GEN) (Q16-17/16 Rapporteur) reports on Project F.4, End-To-End Interoperability. Discussion revealed four possible views of interoperability which might be considered within the project. These views were discussed at length. It was agreed that the drafters of the GII project intended as an ultimate goal that any two terminals operating anywhere on the global network would be able to interoperate when accessing/providing the same service. It was noted that another GII project on network interworking exists. Thus project F.4 should focus on application interworking between the terminals, but should also feed requirements into the network interworking project, and in turn should take account of the results of the latter study. Further discussion concerned how to move forward in the project. The two possibilities might be to work with reference scenarios or to continue work on a general methodology for standards development. Another suggestion was to start with service descriptions and move down to scenarios and protocol profiles after that. It was pointed out that the service description for multimedia conferencing has already been standardized as Rec. F.702. This could be the starting point for scenario development. A modified version of TD-21(GEN) was subsequently reviewed and approved. TD-82(PLEN) is the liaison report from SG16 to JRG-GII for F.4. It defines Interoperability as the information exchange between service/ application entities. Project M.3, Electronic Commerce A draft of the project plan for project M.3 was presented with the proposal that Study Group 16 accept leadership of this project (Annex 1 to TD-81(PLEN), the Q16-17/16 meeting report). Extensive discussion resulted on whether Study Group 16 has the necessary resources and expertise to take on the project. It was agreed that we should be guided by the response to a call for interested persons to contribute to the work. Y. Robin-Champigneul (FT/CNET, France) accepted the task of project coordination for project M.3. It was agreed that the project plan should make reference to the extensive work on this topic in various working groups of the IETF and to the work of other bodies where this information is available. TD-85(PLEN) is the modified draft of the M.3 project plan.
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E-Mail Discussion Lists It was noted that the e-mail discussion lists which were to be set up for discussion of the different GII projects had not materialized. The meeting agreed that all discussion should go through the same list: the one allocated for dis- cussion of Questions 16 and 17 at the TSB-SG16 site. M. Matsumoto will submit the names and e-mail addresses of all participants to the TIES Help-Desk personnel to enroll them as list subscribers. DRAFT OF THE MULTIMEDIA RECOMMENDATION MODEL A draft of the new MM Recommendation model was presented. The new draft presented an inventory of existing series of Recommendations rather than the desired framework. It was therefore rejected with instructions to the drafter (T. Taylor, Nortel) to seek instead to extend the framework provided in the original document. Suggestions were presented for the proposed Appendices listing current Recommendations in force; these lists should cross- reference between the individual Recommendations and the systems to which they are applicable. Q18/16 WP1, INTERACTION OF HIGH-SPEED VOICEBAND DATA SYSTEMS WITH SIGNAL PROCESSING
There were no contributions on this topic and no discussion. No interim meetings are required. At the WP1 plenary, the WP1 Chairman reported that the Rapporteur for Q18/16, M. Sherif (AT&T), was no longer able to continue as Rapporteur as his work area had changed and he is no longer involved in standards activities. The WP1 chair thanked M. Sherif for his contribution to the work of Working Party 1/16. D.174© (France Telecom) proposes the transfer of Question 18/16 to Study Group 15 where the work may be more appropriate, and where more of the relevant experts are participating. WP1 agreed with the France Telecom proposal and accordingly TD-56(WP1/16), a Liaison Statement to SG15, was prepared proposing that they consider taking over this Question. Q19/16 WP3, EXTENSION TO EXISTING ITU-T SPEECH CODING STANDARDS AT BIT RATES BELOW 16 KBIT/S S. Hayashi (NTT/Japan) is the Q19/16 Rapporteur. TD-20(WP3/16) is the Q19/16 agenda and prior meeting report; TD-32(WP3/16) is the Q19/16 meeting report. No interim meetings are planned. ANNEX C TO G.729 APPROVAL The work on G.729 (CS-ACELP) Annexes C, D and E took place in the WP 3/16 meeting. The technical content of G.729 Annex C (Floating point specification for G.729 and G.729 Annex A) was reviewed based on COM16-45, as revised by SG16 during the January-February meeting of SG16 (see COM16-R29, pp. 2-4, with updated file sizes), on Annex 2 to TSB Circular Letter 101, and on D.185© (FT/CNET), Bug correction in G.729 Annex C. The group unanimously agreed to incorporate the suggested technical changes, as summarized in TD-16(PLEN). G.729 Annex C was approved (Decided) by SG16 as COM 16-45 plus TD-16(PLEN). ANNEX D TO G.729 APPROVAL COM16-65 presents the text of new Annex D to G.729, - 6.4 kbit/s CS-ACELP. The characterization test methodology was drafted at the SG16 February meeting and revised and approved in SQEG (speech quality experts group Q22/12) in March 1998. FT/CNET and NTT performed the characterization tests of Version 1.2 of the algorithm and presented the test results. All the requirements were met in both laboratories except for the DCR (Degradation Category Rating) test method under high levels of car noise. It was explained by speech assessment experts present at the meeting that there was not sufficient evidence to conclude whether or not G.729 Annex D has problems with car noise. The group agreed to add a note warning of potential performance limitations with high levels of car noise and unanimously agreed that G.729 Annex D should be approved by SG16. It was Decided as TD-43(PLEN)©. ANNEX E TO G.729 APPROVAL D.186© (France Telecom/University of Sherbrooke) presents design considerations on the test vectors for Annex E to Recommendation G.729; this was recognized as useful information.
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COM16-66 presents the draft text of Annex E to Recommendation G.729 - 11.8-kbit/s CS-ACELP speech coding algorithm, which is the higher bit-rate extension designed to accommodate a wide range of input signals such as speech with various background noise and music. This coder was developed by France Telecom/CNET and University of Sherbrooke, and was originally submitted to the Q19/16 Rapporteur’s meeting in September 1997. The design of test vectors for verification or correct implementation of this algorithm was presented by University of Sherbrooke. The characterization test methodology was drafted in the SG16 February meeting and revised and approved in SQEG/SG12. Ericsson, FT/CNET and NTT performed the characterization tests of version 1.2 of the algorithm and presented the test results. All the requirements were met in all the laboratories and some objectives were also met. The group unanimously agreed that the algorithm has adequate performance and that it should be approved by SG16. It was Decided as TD-44(PLEN). CORRIGENDUM FOR ANNEX H TO G.728 APPROVAL Annex H of G.728 (Variable bit rate LD-CELP operation mainly for DCME at rates less than 16 kbit/s) lacked the detailed description on the modified pseudo-code to be used in the calculation of log-gain (GSTATE(1)). The corrigendum proposed in D.215© (Mitsubishi) provides the additional description on the calculation of GSTATE(1) and the additional values for codebook-related arrays. Q19/16 agreed that the corrigendum should be published in an Implementer’s Guide. It was approved as TD-49(PLEN). ANNEX I - G.728 DETERMINATION Proposed Annex I to G.728 (extensions for robust performance in the presence of frame erasures) used to be an extension of the LD-CELP codec that modified the decoder algorithm to be operated under burst error conditions of mobile radio channels. This extension was suspended because some quality loss was previously found in subjective tests performed with Japanese sentences. D.107 (R. Cox, AT&T) from the January 1998 SG16 meeting presented an improved frame-erasure concealment algorithm that intends to overcome the quality loss in the previous proposal. The meeting agreed that this algorithm is valuable not only at 16 kbit/s but also at 12.8 and 9.6 kbit/s under variable-rate operation. The terms of reference for this extension algorithm is attached as Annex B to TD- 32(WP3/16), the Q19/16 meeting report. The test methodology for this extension was drafted in February 1998 meeting and approved by SQEG/12 March 1998. AT&T tested this algorithm in North American English and NTT tested it in Japanese. The results from both test laboratories were reviewed at this meeting (D.155© and D.203©, respectively). All the requirements were met except for a few conditions that were unique to each of the two languages and were recognized to have little statistical significance. The group unanimously agreed that this proposal should be submitted for Determination at this meeting. G.728 Annex I was Determined as TD-48(PLEN). VBD CAPABILITY FOR THE 40-KBIT/S EXTENSION OF G.728 Although the final version of the test methodology of voice-band data (VBD) capability was finalized in February 1998, no action was taken by the proponent of the candidate algorithm (ECI/MOC Israel) to start testing. No progress was made during this meeting. The group reviewed the schedule and would like to come to closure on the issue at the next meeting. The rapporteur will personally contact the proponent to clarify the situation. The terms of reference for this extension algorithm is attached as Annex A to TD-32(WP3/16), the Q19/16 meeting report. PROPOSAL OF IMPROVING VAD D.145© (CSELT) is a new algorithm to improve VAD (Voice Activity Detector) performance when it is used with a digital speech coding algorithm. This new VAD was developed by the University of Catania and is based on an improved (adaptive) version of the Fuzzy VAD presented (as AH-Q19-06) in September, 1997 at the Bethesda, MD, Q19/16 meeting. Performance evaluation with both subjective and objective measures was presented in comparison with Annex B to G.729 identifying the improvement over G.729 Annex B. The meeting thanked CSELT for the information and suggested that a concrete proposal be submitted via contribution for the establishment of a new work item. LIAISON STATEMENTS TD-28(WP3/16) from Q19/16, Q20/16 and Q21/16 to both SQEG/12 and ITU-R TG8/1 notifies them of the approval of Annexes C, D, and E to Recommendation G.729 and of the Determination of Annex I to Recommendation G.728. SG16 thanks SQEG/12 for elaborating the characterization test methodology and ana- lyzing the test results for both draft Annexes D and E to G.729. It also thanks SQEG/12 for reviewing the evaluation test methodology for the proposed Annex I to G.728. WP3/16 would like to ask SQEG/12 and Q14/12 to consider the identification of proper methods for the assessment of VAD/CNI/DTX (discontinuous transmission)
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algorithms in particular in the presence of background noise, which will be part of future standardization work in SG16. Q20/16 WP3, AUDIO AND WIDEBAND CODING IN PUBLIC TELECOMMUNICATION NETWORKS R. Drogo De Iacovo (CSELT/Italy) is the Q20/16 Rapporteur. TD-8(WP3/16) is the meeting agenda. TD- 9(WP3/16) is the Q20/16 progress report. TD-29(WP3/16) is the report of this meeting. The current objectives of Question 20/16 are to evaluate the results of the selection test and plan for future activities. WIDEBAND CODEC TEST RESULTS COM16-71 (PictureTel) is a detailed description of the PictureTel candidate algorithm for the wideband (50 - 7000 Hz) audio coder for multimedia communications with a 16 kHz sample rate. TD-10(WP3/16) (Rapporteur) contains version 1.2 (May 1998) of the Subjective Selection Test Plan for the ITU- T Wideband codec. Five listening laboratories participating in the selection listening tests (DT Berkom, FT/CNET, FUB, NORTEL and NTT-AT) and presented their results. All of them were judged compliant in meeting its deliverables according to the contents of the signed Memorandum of Understanding. This work was funded by PictureTel, who provided the candidate algorithm, at the 50% level. Each of the listening laboratories are expected to send a bill for the balance to ITU-T TSB for payment. D.146© CSELT - FUB D.151© Deutsche Telekom Berkom GmbH D.184© France Telecom/CNET D.190© Nortel D.204© NTT/NTT-AT TD-12(WP3/16) (Q22/12/SGEQ/12 Chairman, P. Usai, CSELT) presents a global analysis of the wideband codec selection tests. From the global analysis it was shown that the codec under test (CuT) has very good performance with music signals and with background noise at 32 kbit/s. In the presence of clean speech, however, the CuT doesn’t provide the required performance in many cases. An overview of the selection test results is included in Annex Q20.A of the Q20/16 meeting report, TD-29(WP3/16) which also includes Terms of Reference and associated time schedules. The following areas were identified as clearly needing improvement before the terms of reference can be said to be met: • Clean speech with frame erasures - performance at the three bit rates • Tandem clean speech performance for 24 and 32 kbit/s • Two and three tandem performance with office noise at 16 kbit/s • Three tandem performance with frequency harmonic noise at 16 kbit/s. It was concluded that the measured performance of the tested algorithm does not satisfy all the terms of reference, in particular for speech signals in (a) tandem connections and in (b) connections with 3% random frame erasure. After the discussion on the selection test results, it was agreed to restart the competition for a 24, 32 kbit/s wideband algorithm for speech and music signal with a very short time schedule. D.196© (Canada) raises the need to consider new standardization of a 7-kHz codec at 16 kbit/s and below devoted for speech signals. TEST RESULTS AND ORGANIZATION OF FUTURE ACTIVITIES D.161© (Lucent) expresses concern on the present state of the standardization activities with regards to wideband speech coding. It requests that no further compromises be made in the relaxing of requirements. As a first way forward, Q20/16 discussed the possibility of considering specific applications and, taking into account the conditions with requirement met, starting an optimization phase. Due to the number of failures in meeting the requirements and the lack of organizations willing and able to enter this optimization phase in order to improve the codec performance, it was decided to explore other ways to go forward. Taking into account the need to proceed rapidly towards an ITU-T wideband standard and, at the same time, noting the state of the art in wideband coding, Q20/16 agreed to proceed with a very short time schedule for a 24, 32 kbit/s wideband algorithm capable of coping with speech and music signals; it was agreed to leave the wideband 16 kbit/s (and around) bit-rate(s) as a longer new project activity mainly focused on speech signals.
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For the 24 and 32 kbit/s algorithms this assures fair competition; it allows other candidates to participate in the selection process. Consequently, the Terms of Reference and time schedule were revised (Annex Q20.B to TD-29(WP3/16)) and the following agreements were reached. The aim is to have the standard algorithm at the end of the very short time schedule: 1. The qualification phase is not performed and no qualification test is required of the candidate proponents; they have to sign a Letter Of Intent (LOI) and send it to ITU-T TSB (F. Bigi). The LOI represents a commitment for the proponents to enter the selection phase and share the cost of the subjective tests. The total amount to be shared will be known when the MoUs (Memoranda of Understanding) are prepared by ITU-T TSB and sent to the interested parties. Editor’s note: On October 7, 1998, an e-mail from S. Campos-Neto noted that the Letter of Intent is now available from the ITU at: ftp://[email protected]/u/tsg16/sg16/wp3/loi.rev1.doc where “account” is a valid TIES account with access to the SG16 Informal FTP area. The Rapporteur for Q20/16 will also be informed by the candidate proponents of their intentions and the Rapporteur will notify the Q20/16 reflector of candidate submissions. 2. Two MoUs will be prepared by ITU-T TSB, as in the previous wideband exercise: MoU “A” between ITU-T and candidate proponents, MoU “B” between ITU-T and listening laboratories. 3. Each candidate proponent will perform the fixed-point software host laboratory processing for its own candidate conditions. As done in the previous wideband selection test, the candidate proponent will process the candidate conditions, and the listening laboratories will provide pre-processing of the source material and processing of reference conditions utilizing the ITU-T Software Tool Library. Spot checking of the processing done at the proponent laboratories will be performed; the procedure will be coordinated by the Rapporteur for Q20/16. The spot checking will be started after the end of the host laboratory sessions and will require that each candidate proponent check the processing performed by another proponent. With this aim, each candidate proponent shall receive, under NDA (Non Disclosure Agreement), the executable code and batch files to perform the spot checking activity. CD-ROM is the preferred media to exchange files (unless differently agreed) in DOS format and executables for a Pentium Windows 95 platform. Moreover, a similar spot checking activity should be performed by listening laboratories as regards the pre-processed source material and processing of the reference conditions using the same exchange media and platform as agreed for the above-mentioned spot checking activity carried out at the host laboratories. 4. The time schedule for wideband coding at 24 and 32 kbit/s (see Annex Q20.B of TD-29(WP3/16)) was prepared, planning for Determination in May 1999 and Decision in September 1999 (co-located meeting with SG12). 5. The Terms of Reference (ToR) were reviewed and it was agreed to leave the 16 kbit/s for a subsequent new standardization activity. The 16 kbit/s compared to G.722 at 48 kbit/s (one third of bit-rate reduction) is not achievable with the current state of the art. Moreover, looking at the results gained in the testing of ITU-T wideband coding during the past five years, it was concluded from the test results that the state of the art likely allows a reduction of 24 kbit/s while maintaining the same performance of G.722 for speech and music. Based on actual test results, the ToR were revised, calling for an algorithm at 24, 32 kbit/s that matches the G.722 performance at 48, 56 kbit/s, respectively, whereas the objective, that will be tested in the selection phase, remains matching G.722 performance at 56, 64 kbit/s. 6. The Rapporteur will also send the Liaison Statement originated by Q20/16 to the SQEG/SG12 e-mail reflector and directly to the SQEG Chairman to minimize the risk of delay in the wideband time schedule. Q20/16 specifically addressed the issue of sharing 100% of the total cost of the subjective tests among candidate proponents. If PictureTel is a candidate proponent, it should be taken into account that they already paid for the previous selection exercise and a compensation mechanism should be adopted to equally distribute the final expenditure.
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The feeling of many potential candidates present at the meeting was that it would be very difficult for them to gain acceptance of this proposal by their respective managements. For that reason they did not accept this compensation mechanism and asked to share 100% of the new costs among proponents, including PictureTel. Nevertheless, when the actual set of candidate proponents is known, the question can then be decided by the proponents. Editor’s note: As of October 28, LOIs from PictureTel and NTT have been received and accepted by the ITU. Lucent Technologies previously notified the Rapporteur that they do not wish to participate in this phase. Q20/16 also addressed the issue of C-source code availability and proper distribution. It was agreed that an escrow copy of the C-source code will be sent by each of the proponents to the ITU-T TSB (deadline is two months before the SG16 meeting). No software distribution will take place before the SG16 meeting. At the next SG16 meeting, if a Determination occurs, the issue of software distribution will be addressed and the guidelines that are expected from TSAG on the subject will be properly considered. Starting from the considerations contained in D.196 (Canada), it was agreed to request contributions for a new wideband (7 kHz) coding activity around 16 kbit/s with focus on speech. An Annex to TD-29(WP3/16) contains a summary of possible applications and technical features for the new wideband algorithm as discussed within Q20/16. These include: ISDN videotelephony on Basic Rate Access, ISDN wideband telephony (e.g., for multichannel applications), wideband transmission over Internet, packet applications (B-ISDN with ATM, PCME, DCME), wideband over indoor wireless and cellular, and PSTN applications (e.g., point-to-point links for business applications). LIAISON STATEMENTS TD-01(WP3/16) is a liaison from Task Group 8/1 on Speech and Multimedia coding for IMT-2000. It requests continuing information on the performance of the extension to G.729 at 11.8 kbit/s, and other candidate set(s) of video and audio codecs for IMT-2000 applications. TD-04(WP3/16) is a reply from Q22/12 (February 1998 meeting) on the progress of speech coding testing and related issues. BT, France Telecom, Nortel, NTT and Rockwell have identified themselves as provisionally able to conduct the tests. However the issue of funding will need to be addressed by SG16. TD-06(WP3/16) is a liaison from MPEG with comments on audio coding and audio verification tests, and a copy of MPEG-4 Audio Verification Test Specifications - NADIB (Narrow Band Digital Broadcasting) Part. This liaison notes that MPEG-4 is focused on narrow band audio broadcasting, music on the Internet and mobile video transmission; verification testing will be aimed at evaluating the performance in these specific application areas. TD-28(WP3/16) contains all the output liaison statements from Q19/16, Q20/16 and Q21/16 regarding Progress on Speech Coding Issues. Included in TD-28(WP3/16) is a liaison to inform SQEG (Q22/12) about the updated Terms of Reference and time schedule for ITU-T wideband coding at 24, 32 kbit/s. It also asks support in developing an appropriate selection test plan. The liaison requests to have the selection test plan for wideband coding at 24, 32 kbit/s ready at the end of next SG12 meeting (December 4, 1998). TD-28(WP3/16) also includes two other liaisons to ITU-R TG 8/1 and SG11 asking advice on foreseen applications and related requirements for the new wideband coding activity around 16 kbit/s started at the present SG16 meeting. Q21/16 WP3, ENCODING OF SPEECH SIGNALS AT BIT RATES AROUND 4-KBIT/S The Q21/16 Rapporteur is P. Barrett (BT, UK). The Q21/16 agenda is TD-21(WP3/16); the report of interim activities is TD-22(WP3/16). TD-23(WP3/16) is the report of this Q21/16 meeting. No interim meetings are planned. The current objective of Q21/16 is to select an algorithm or algorithms that are likely to meet the terms of reference for the future ITU-T 4-kbit/s speech coding standard (G.4k). Candidate proposals are assessed on the basis of subjective test results produced according to the 4-kbit/s qualification test plan. SUMMARY Q21/16 reviewed qualification results from eight organizations. However, none of the proposals fully met the requirements necessary to enter the selection phase; further submissions will be reviewed in September, 1999. A
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new qualification procedure has been defined whereby the subjective tests for all 4-kbit/s candidates will be performed using a common laboratory (or laboratories). The terms of reference (ToR) for speech coding at 4-kbit/s remain unchanged. The revised target for approval of G.4k is the first quarter of 2001. RESULTS During the WP3/16 Plenary in February 1998, it was agreed that organizations submitting candidates to Q21/16 would be required to provide demonstration speech material as a qualification deliverable. A procedure for the production and distribution of the demonstration material, based on the use of common unprocessed speech, was agreed by correspondence during July and August 1998. The Rapporteur received processed material from all eight candidate proponents by the agreed deadline of 2 September. This was placed on the ITU-T ftp server using a filename mapping known only to the Rapporteur. The Rapporteur stressed that the purpose of this demonstration material was to provide WP3/16 with an indication of the current performance of 4-kbit/s speech coding technology, and that although the demonstration material might contribute to the decision over whether to begin the 4-kbit/s selection phase, it would not be considered when deciding which particular algorithms could go forward. Q21/16 agreed that the demonstration material would be removed from the ITU-T ftp server after this Study Group meeting, and that the filename mapping would remain secret. CANDIDATE PROPOSALS Candidate proposals were presented by COMSAT, Fujitsu, Matsushita, Mitsubishi, NTT, Rockwell/Nortel, Toshiba and Voxware. A summary of the algorithms and qualification results is given in Annex Q21.A to the Q21/16 meeting report, TD-23(WP3/16). Input documents are shown in Table 5. SCHEDULE Q21/16 reviewed the qualification results with respect to the ToR (Terms of Reference) for 4-kbit/s speech coding. Although it was acknowledged that further delay in Q21/16 could lead to G.4k missing some windows of opportu- nity, the consensus of the meeting was that the ITU-T 4-kbit/s speech codec should deliver the performance reflected in the ToR. Given that none of the candidates passed all of the requirements, Q21/16 decided to postpone the deadline for candidate submissions. It was agreed that the next Q21/16 qualification tests will be coordinated by SG16, and performed at a common laboratory (or laboratories). The main disadvantages of this approach are the need for candidate proponents to pay external organizations to perform the subjective tests, and the additional delay incurred by the use of a small number of laboratories. However, these factors were felt to be outweighed by the advantage of removing variables such as source material, test language and replay equipment from the qualification phase. The number of listening labora- tories and languages has yet to be agreed, but at least two listening laboratories (COMSAT and Nortel) stated that, in principle, they were interested in participating. BT provisionally stated that it could act as host laboratory. Organizations wishing to submit a 4-kbit/s speech coding algorithm to Q21/16 must make a verbal declaration of intent during the next SG16 meeting, otherwise their candidate will not be included in the qualification phase. Organizations wishing to act as a laboratory for the qualification phase should provide the following information to the Rapporteur not later than six weeks before the SG16 meeting in May 1999: 1. The cost per candidate, per experiment; 2. The maximum number of candidates that can be accommodated; 3. The time required to perform the listening phase for different numbers of candidate algorithms (one to the maximum number inclusive); 4. Whether the laboratory will perform the host laboratory function.
Number Source Title D.152© Mitsubishi High Level description of Mitsubishi 4 kbit/s codec and test results D.154 Matsushita High Level description of Matsushita 4 kbit/s codec and test results D.157© COMSAT Qualification test results of COMSAT 4 kbit/s codec D.165© COMSAT High Level description of COMSAT 4 kbit/s codec D.175© Rockwell High Level description of Rockwell/Nortel 4 kbit/s codec D.176© Rockwell Qualification test results of Rockwell/Nortel 4 kbit/s codec
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D.177© Rockwell IPR statement D.178© Voxware High Level description of Voxware 4 kbit/s codec D.179© Voxware Qualification test results of Voxware 4 kbit/s codec D.180© Voxware IPR statement D.201© Fujitsu High Level description of Fujitsu 4 kbit/s codec and test results D.205© NTT High Level description of NTT 4 kbit/s codec and test results D.209© Toshiba High Level description of Toshiba 4 kbit/s codec and test results Table 5. Input Documents for ITU-T 4-kbit/s speech coding standard (G.4k). In order to keep the cost of the qualification phase to a minimum, it was agreed that the experiments funded by the candidate proponents will only be performed in a single language (which will be the same for both qualification experiments). Proposals from laboratories wishing to repeat the qualification experiments in a second or third language will be considered if they incur little or no extra cost to the candidate proponents. The cost per candidate, per experiment is expected to be in the order of US$10K (i.e., US$20K per candidate). The schedule was revised such that the new target date for Decision of the ITU-T 4-kbit/s speech coding recommendation (G.4k) is the first quarter of 2001. The revised schedule is in Annex Q21.C to TD-23(WP3/16), the Q21/16 meeting report. TERMS OF REFERENCE AND QUALIFICATION TEST PLAN TD-13(WP3/16) (Q21/16 Rapporteur, P. Barrett) is the subjective qualification test plan for 4-kbit/s coding. There were no contributions on the ToR, although Voxware noted that in their qualification tests the provisional requirement for random bit errors (G.729 at a BER of 0.1%) gave better performance than G.726. The Rapporteur invited contributions on this topic, and stated that he would investigate the possibility of obtaining bit error patterns from Q11/16. The performance requirements for random bit errors and bursty detected frame erasures remain for further study. The requirement to pass DTMF signals was questioned, because systems using low bit-rate speech codecs increasingly send this information by means of signaling. A note was added to the ToR to reflect this fact, but the need to pass DTMF tones remains a requirement. One of the candidate proponents stated that they were unable to find a telephone handset meeting the specification in P.830. It was agreed that a liaison statement will be sent to Q22/12 (SQEG) requesting clarification on the use of headphones in future 4-kbit/s subjective tests (contained in TD-28(WP3/16), draft liaison statements from Q19, 20 and 21/16). Finally, it was also suggested that the processing diagrams in the qualification test plan are unclear with respect to the inclusion of G.711 stages. New diagrams will be prepared for approval by SQEG. LIAISON STATEMENTS A liaison statement was drafted to inform SQEG of the revised 4-kbit/s schedule and qualification procedure, and to request guidance on the use of headphones in future 4-kbit/s qualification and selection tests. A liaison statement was drafted to ITU-R TG 8/1 to inform them of the revised 4-kbit/s schedule and terms of reference. Q22/16 WP3, SOFTWARE AND HARDWARE TOOLS FOR STANDARDIZATION OF SPEECH AND AUDIO CODING ALGORITHMS The Q22/16 Rapporteur is S. F. Campos-Neto (COMSAT/USA). TD-18(WP3/16) is a report of the interim activities. The Q22/16 meeting report is contained in the WP3/16 report, TD-62(PLEN). No interim meetings of Q22/16 are planned. Currently Q22/16 is dealing with the maintenance and future enhancements of the STL96 (Software Tool Library96). At the last SG16 meeting, an “unofficial” update (evolving STL, eSTL) was made available (the evolving STL released in January 1998 [eSTL9801] is available to ITU-T members under request from the Rapporteur) and the list of action points (see TD-62(PLEN), Annex Q22.A) was revised.
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Little progress was performed in this period (see TD-18(WP3/16), the report of the interim activities), although some minor bugs were corrected and identified, and some preliminary studies were performed. On the investigation of the alternative calculation of the active level method proposed by Prof. Kabal (COM 16- R28), preliminary comparison showed almost identical measurements when the speech files had been pre-equalized to -26 dBov. Further tests will investigate the effect for a range of input speech level files. When finalized, the results will be posted to the WP 3/16 reflector. The modified (to fix the bugs identified) demo programs will be uploaded to the ITU-T informal FTP area for SG16 under the WP3 Q22 directory. Editor’s note: an e-mail from S. Campos-Neto on October 5, 1998 noted that these files have been uploaded to: ftp://[email protected]/u/tsg16/sg16/wp3/q22/new-9809/new9809.zip where “account” (without quotes) is a valid TIES account and password. LIAISON STATEMENTS Q22/16 reviewed TD-3(WP3/16), a Liaison Statement from Q13/12 on the PSQM (P.861, Objective quality measurement of telephone-band [300-3400 Hz] speech codecs, 2/98) software and from Q14/12 on speech voltmeter aspects (P.56, Objective measurement of active speech level) related to software tools. The group noted the guidelines on the use of test vectors for testing the PSQM implementation, but the Rapporteur reported that the reference implementation of the PSQM software has been taken out of circulation by the TSB, due to IPR issues related to P.861. As a consequence, this work was temporarily halted. Regarding the speech voltmeter, the group created an action item to identify and implement optional filter programs to band-limit the input signals used by the speech voltmeter demo programs. Q23/16 WP1, PCM MODEMS The Q23/16 Rapporteur is L. Brown (Motorola ISG, USA). The agenda for the meeting is TD-24(WP1/16). TD-14(WP1/16) is the report of the Red Bank, New Jersey, Q23/16 Rapporteur meeting (May 1998); TD- 15(WP1/16) is the report of the Quebec City, Canada, Q23/16 Rapporteur meeting (July 1998). An interim Rapporteurs meeting is planned for December 7-10, 1998 in San Diego, California. LIAISON TD-4(WP1/16) is a liaison from SG15 concerning voice-band data over ATM networks. It recognizes the concerns of Q23/16 regarding adaptive build-out delay. Q8/15 added text noting the use of a fixed (300 µs - 2 ms network operator set) build-out buffer to delay playout of the packet/cells. The approved liaison reply (TD- 39(WP1/16)) thanks Q8/15 for their work but raises the issue of when adaptive delay is used. It notes that a statement in I.741 specifying a means to disable adaptive build-out in the case of a data call might be helpful. TD-6(WP1/16) is a liaison from Q4/15 to multiple SGs concerning identification and characteristics of PSTN signals that may interfere with splitterless ADSL (G.lite). The liaison reply, in TD-52(WP1/16) notes the possibility of billing tones (see ETS 300 001) as signals outside the 4 kHz band. TD-13(GEN) is a liaison from SG15 requesting comment and identification of contacts pertaining to their draft ANT (access network transport) standardization plan; Q23/16 approved a liaison reply, indicating that they should add the V-series Recommendations from SG16 and delete the cited H.2xx documents, which do not relate to access transport. The liaison is in TD-44(WP1/16). RECOMMENDATION V.90, PCM MODEM Q23/16 agreed to the editorial changes to draft Recommendation V.90 (COM 16-64) given in TD-6(PLEN) items 2-5. They also considered and approved, with revision, the proposed Appendix I (example network configuration) for V.90 contained in TD-6(PLEN). The updated text for the Appendix is contained in TD-45(PLEN). PROPOSED RECOMMENDATION V.ADM TD-23(WP1/16) is the updated issues list for the ongoing work on PCM modems as updated at the Q23/16 Rapporteur meeting in Quebec City. This was revised to TD-40(WP1/16), which was then approved by Q23/16. TD-19(WP1/16), the proposed baseline text for V.adm, based on the agreements reached at the Quebec City meeting (July 1998), was approved with minor revision.
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D.162© (B. Barazesh, Lucent) proposes work on the definition of Phase 1 of the handshake for V.adm, in particular on the detection of “clear” channels, i.e., channels with no digital impairments. D.199© (K. Chu, Rockwell, US) addresses several of the open issues on V.adm. D.200© (T. Liau, Rockwell, US) raises concern regarding the use of a DC offset for the V.adm digital connectivity probing sequence. TD-33(WP1/16) is a compilation of the contributions from the Quebec City meeting addressing open issues for V.adm. TD-41(WP1/16) is the report of an ad hoc session that reached agreement on open issues for V.adm. The revised report is in TD-51(WP 1/16). It reports that one proposed set of DCP (Digital connectivity probing) signals (repeating octets) would be before CM and after optional CI in Phase 1 or alternatively a DC offset could be added to CM and JM Phase 1 signals. During the deliberations, the group also approved the following: • Inclusion of an Appendix discussing the typical network configuration for V.adm • Optional support of V.8bis ahead of Phase 1 startup for V.adm • The use of the signal point represented by Ucode 66 for SCR in Phase 3 • Handling of interchange circuits 104 and 106 during resynchronization and retrain, and circuits 107 and 109 during disconnect (after a 6 second timeout). The Rapporteur will update the issues list to reflect all of the agreements reached during this meeting. TD-46(PLEN) is the revised text for proposed Recommendation V.adm incorporating all of the agreements. The remaining open issues for V.adm are: • Finalization of the provisional agreement on the structure of Phase 1 of the startup procedure, which depends on the definition of robust DCPc (calling) and DCPa (answering) signals • Further consideration of test loops (section 9) • Clarifications to the Scope and the Title of the Recommendation pertaining to the definition of switched digital network, and type(s) of network over which V.adm is intended to operate • Work on Appendix describing typical network configurations for V.adm These issues will be addressed at the interim Rapporteur’s meeting. Q23/16 agreed that proposed Recommendation V.adm is sufficiently mature to be forwarded to SG16 for Determination. V.91 (former V.adm) was Determined at the closing plenary as TD-72(PLEN). V.ADM INTELLECTUAL PROPERTY To date, the following companies have indicated verbally that they may have Intellectual Property pertaining to proposed Recommendation V.adm: Lucent Technologies, Rockwell, 3Com, Motorola, Matsushita, and Lake Datacomms.
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MEETING ROSTER OF STUDY GROUP 16, SEPTEMBER 14 – 25, 1998, GENEVA, SWITZERLAND
Pierre-André Probst, Swisscom, Switzerland SG16 Chair George Helder, PictureTel, US SG16 Vice Chair John Magill, Lucent, UK SG16 Vice Chair Federico Tosco, CSELT, Italy SG16 Vice Chair
Country Company Name ETSI Gur Kimchi ETSI Paolo Usai INMARSAT Eyal Trachtman INTELSAT Andrew C. Lee TSB Fabio Bigi Austria Gerhard List Austria Post und Telekom Austria Michael Blaschitz Austria Post und Telekom Austria Paul Muzak Austria Post und Telekom Austria Klaus Sambor Brazil Georges Claessen Canada Redwan Salami Canada Thomas Taylor Canada Mitel Dave Walker Canada Nortel (Canada) Nicole Gallant Canada Nortel (Canada) Peter Yue Chile Eduardo Vera China Yu Hong Bin China Fei Wen Duan China Jiang Lin Tao China Xu Yun Tao China Dai Xiao Hui China Lin Xin Yue Finland Helsinki Telephone Co. Markus Backstrom Finland Helsinki Telephone Co. Juha Kauppi Finland Helsinki Telephone Co. Teemu Varonen Finland Nokia Matti Alkula Finland Nokia Ari Heikkinen Finland Nokia Harri Honko Finland Nokia Marko Luomi Finland Nokia Lippo Rantanen Finland Nokia Pekka Rissanen France Daniel Battu France Jean Pierre Blin France Lucien Bourgeat France Pierre Combescure France Yves Robin-Champigneul France France Telecom Gerard Dupin France France Telecom Isabelle Haignere France France Telecom Claude Lamblin France France Telecom Franck Lelong France France Telecom Catherine Quinquis France France Telecom Georges Sebek France MATRA Telecommunications Francois Capman France MATRA Telecommunications Carlo Murgia France MATRA Telecommunications Didier Rocchia France SAGEM Gerard Lachaussee Germany Manfred Magele Germany Rolf Ruggeberg Germany Istvan Sebestyen Germany Alcatel SEL Klemens Adler
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Germany Deutsche Telekom Ralf-Rainer Damm Germany Deutsche Telekom Siegfried Rausch Germany Deutsche Telekom Joachim Stegmann Germany Siemens Robert Callaghan Germany Siemens Martin Euchner Germany Siemens Gerard Hofer Germany Siemens Karl Klaghofer Germany Siemens Markku Korpi Germany Siemens Gerald Meyer Germany Siemens Imre Varga Germany Siemens Bernard Wimmer Germany TELES Jorg Ott Germany TELES Stephen Wenger Hungary MATAV Hungarian Telecomm Tivadar Szabo Ireland Lake Datacomms Michel McLaughlin Israel Ami Amir Israel Philippe Klein Israel Goory Ronen Israel Sasha Ruditiski Israel Uzi Shalev Italy Giuseppe Rinaldo Italy Mauro Falcone Italy CSELT Rosario Drogo De Iacovo Italy CSELT Federico Tosco Italy Italtel Renata Guarneri Japan Mitsuji Matsumoto Japan Junichi Nakazawa Japan Sakae Okubo Japan Akihiko Tsukui Japan Canon Masao Hosaka Japan CIAJ Keiichi Hibi Japan Fujitsu Yasuji Ota Japan Fujitsu Kiyoshi Sakai Japan KDD Shigeyuki Sakazawa Japan KDD Hideaki Yamada Japan Matsushita Electric Industrial Akira Atsuta Japan Matsushita Electric Industrial Hioryuki Ehara Japan Mitsubishi Electric Yushi Naito Japan Mitsubishi Electric Hirohisa Tasaki Japan NEC Yoshihisa Aotani Japan NEC Hidenobu Harasaki Japan NEC Masahiro Serizawa Japan NTT Shiji Hayashi Japan NTT Naoki Kobayashi Japan NTT Hiroshi Koyano Japan NTT Kazunori Mano Japan NTT Takahiro Muraki Japan NTT Shigeaki Sasaki Japan NTT Mobile Comm Network Toshiro Kawahara Japan NTT Mobile Comm Network Takashi Suzuki Japan Oki Electric Industry Yasuo Aoyagi Japan Oki Electric Industry Yasubumi Chimura Japan Oki Electric Industry Minoru Miyazaki Japan Toshiba Masimi Akamine Japan Toshiba Barry Aronson Japan Toshiba Eizo Fujisawa Japan Toshiba Yoshihiro Kikuchi Japan Toshiba Kimio Miseki
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Japan Toshiba Hirokazu Tanaka Japan Toshiba Toshiaki Watanabe Korea Don Whan Hyun Korea Samsung Yong Duk Cho Morocco Driss Lamsane Poland Andrzej Wykrota Slovak Republic Slovak Telecom Aljosa Salgovic Spain Enrique Berrojalvis Sweden Gunnar Hellstrom Sweden L.M. Ericsson Bo Burman Sweden L.M. Ericsson Eric Ekudden Sweden L.M. Ericsson Magnus Hallenstal Sweden L.M. Ericsson Jan Holm Sweden L.M. Ericsson Mickey Nasiri Sweden L.M. Ericsson Anders Svennevik Sweden Telia Annika Kilegran Switzerland Armin Blum Switzerland Rene Koch Switzerland Siemens Schweiz Rudolph Hasler Switzerland Swisscom Pierre-André Probst Syrian Arab Republic Souad Dahdal Syrian Arab Republic Mohamed Rafic Ghannam Syrian Arab Republic Nabil Kisrawi Syrian Arab Republic Bassema Koueder Thailand Somyot Tanapirunthorn The Netherlands KPN Jeroen De Muijnck The Netherlands KPN Cor Quist UK William Pechy UK BT Paul Barrett UK BT Alistar Farquharson UK BT Mike Nilsson UK BT Joseph Pointer UK BT Andrew Woollett UK GPT Nicholas Winch UK Hayes Microcomputer Products John Moughton UK Lucent Mike Buckley UK Lucent John Magill UK MADGE Michele Bozier UK MADGE Andrew Draper UK Panasonic Standards Europe Alan Pugh UK Racal Datacom Chris Firth Ukraine Igor Usov Ukraine Mykola Vakulenko Ukraine Alexander Varnosov USA An Nguyen USA Andrea Saks USA Bruce Degrasse USA Gary Fereno USA Granger Kelley USA Mark Neibert USA Patrick Murphy USA Paul Jones USA Radhika Roy USA 3-COM Fred Lucas USA 3-COM Richard Stuart USA 3-COM Richard Williams USA Analog Devices Rao Nuthalapati USA Ascend Comm Dale Skran
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USA AT&T Richard Cox USA Bell Atlantic Katrina Hopkins USA Bellcore Raymond Hapeman USA Bellcore Ralph Jensen USA Bellcore Hong Liu USA Cirrus Logic Vedavalli Krishnan USA Cisco Systems Rich Bowen USA COMSAT Corp. Simao Campos-Neto USA COMSAT Corp. Suat Yeldener USA Databeam Neil Starkey USA Delta Information Systems Gary Thom USA ESS Technology Jordan Cookman USA Hayes Microcomputer Products Bruce Adams USA IBM Ali Sadri USA Intel Narjala Bhasker USA Intel Vineet Kumar USA Lucent Carle G. Wray USA Lucent Glen Freundlich USA Lucent Sean Ramprashad USA Lucent Zhongjin Yang USA Microsoft Jane Dailey USA Microsoft Toby Nixon USA Motorola Info. Systems Les Brown USA Nokia Senthil Sengodan USA Nortel (USA) Francois Audet USA Nortel (USA) Slobodan Jovanovic USA PictureTel Antony Crossman USA PictureTel Mark Duckworth USA PictureTel Kaynam Hedayat USA PictureTel George Helder USA PictureTel David Lindbergh USA PictureTel Patrick Luthi USA PictureTel Marshall Schachtman USA PictureTel Gary Sullivan USA Polycom Matt Collier USA Qualcom Amitav Das USA Qualcom Peter Jackson USA Rockwell International Keith T. Chu USA Rockwell International Tom Geary USA Rockwell International Thomas C. Liau USA Sun Microsystems Jenn Yeh USA Videoserver Georges Kajos USA Videoserver Mark Reid USA Videoserver Irina Suconick USA Voxware Robert Zopf USA VTEL Smita Gupta USA VTEL Joon Maeng
42 Vol. 9.8 Copyright © CSR 1998 November-December 1998 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF ETSI TM6 ACCESS TRANSMISSION SYSTEMS ON METALLIC CABLES, SEPTEMBER 21 – 25, 1998, VIENNA, AUSTRIA
Note: As of November 1, 1998, any user can now access, free of charge, the complete range of ETSI Publications, including European Standards in the telecommunications series (EN, ETS, I-ETS, TCR-TR, AN, EG, ES, ETR, GTS, NET, SR, TBR, TR, TS). Use the Publications Download application located at http://webapp.etsi.org/publicationssearch to download individual copies of ETSI Publications in Adobe Acrobat Reader format (.pdf). H.-J. Frizlen (ETSI STF, Ericsson) is the TM6 Chair. Sixty-two delegates, representing fifteen countries including Slovenia and the Czech Republic and including new delegates from the former TM3 Working Party A, were registered. Documents TD-1 and TD-2 are the agenda and summary of work items extracted from the ETSI database. TD-0 (A. Carrick, ASCOM and acting TM6 secretary) is the updated list of abstracts received at the start of the meeting. The new group ANAI (Access Network Architecture and Interfaces), formerly TM3 Working Party A, now takes part in the TM6 work; it will hold fewer meetings than TM6, roughly one meeting of ANAI for two TM6 meetings. B. Orth (DTAG) is the temporary rapporteur of ANAI. Except for the ISDN-BA rapporteur, whose work is completed, the TM6 rapporteurs (ADSL, VDSL and HDSL/SDSL) were confirmed. Two new rapporteurs were appointed within ANAI: A. Profumo (ITALTEL) is rapporteur of the RTR/TM-03075, “Broad-band access digital section and NT functional requirements”; P. Battistello (France Telecom) is rapporteur of REN/TM-03086, “Cell based UNI for 155 Mbit/s and 622 Mbit/s”. An editing group, chaired by Mr. Gindle (Austrian Telecom), will establish a list of definitions and abbreviations relating to TM6 documents. This is not a rapporteur group because of the short duration of its task, and no work item was created within TM6. The TM6 Chair attended the TM meeting held in Helsinki September 14-18. The terms of references of TM6 have been changed because of the merger with the former TM3 working group; TM6 number remains TM6 because of its relations to T1E1 and ITU-T.
FSAN (FULL SERVICE ACCESS NETWORK) LIAISON D. Clark (British Telecom) gave a presentation (WD-23) of the activity of FSAN and invited manufacturers to participate in the FSAN Boston meeting, October 7-8, 1998. FSAN, a telco oriented body, was convened to define the system requirements (especially spectral compatibility issues) for VDSL as an integral part of a full service access network. Since the work of FSAN is vital to TM6, some members felt that this work should be done within ETSI. The TM6 Chair stated that collaboration with FSAN has been good and did not see any reason why it should not continue. T1E1 LIAISON There are no formal liaison officers from T1E1 to TM6, and the TM6 Chair regrets that situation. L. Humphrey (Nortel) read a liaison statement from E. Eckert (Chair, T1E1) to the TM6 Chair indicating completion of work on ADSL document issue 2 and gave a verbal report of the last T1E1 meeting. All letter ballot comments on T1.413 issue 2 have been resolved; it should now be moving to publication. ANSI will most likely recommend that work on xDSL (all the different Digital Subscriber Line services) be started within ITU-T, especially when dealing with spectral compatibility; the work within T1E1 on spectral compatibility has not been very successful and has led more to a spectral incompatibility. The RADSL (Rate-Adapting ADSL) document has been sent to vote as a Technical Report, not a Standard. ADSL FORUM LIAISON B. Dugerdil (Motorola), the official liaison between TM6 and ADSL, was unable to attend the last ADSL Forum meeting. Liaison statements WD-01 (transmittal document requesting ETSI comment on WD-02) and WD-02 (working text for ATM over ADSL Recommendation) were received from ADSL. They were assigned to ANAI for study and reply.
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TM LIAISON At the instigation of British Telecom in the TM meeting, TM approved a liaison statement to ITU-T SG15 Q4 stating that ITU-T should not start work on VDSL (Very high speed ADSL) as long as the regional standard bodies have not completed their work. TM6 was asked to endorse liaison statement WD-05 (from Deutsche Telekom AG, France Telecom, Telia, Sagem, Nokia and Sonera in support of the earlier BT position) and to add names to the list of members supporting those liaison statements; TM6 drafted a similar liaison statement concerning SDSL (WD-06, source BT, Deutsche Telekom AG, France Telecom, Telia and Sagem). Some members feel that ITU-T should be kept aware of the progress of the work within ETSI; others feel the contrary. Also at the instigation of British Telecom in the TM meeting, two working documents (WD-03 and WD-04) were liaised to TM6 concerning potential problems raised by the application of the just-approved CTR (Common Technical Requirements) 21; one problem is that a non-voice TE (Terminal Equipment) approved to CTR 21 (TBR [Technical Basis for Registration] 21, Requirements for pan-European approval for connection to the analog PSTN) may generate noise above 200 kHz which will disturb ADSL and other xDSL TEs; another problem is that CTR 21 cannot be applied to G.lite-like TEs and/or to other TEs specified by the Home Appliance Association and which use the non-voice part of the available line spectrum; there is a gap in the pan-European approval requirements for that equipment. An ad-hoc group was constituted under the responsibility of K. Foster (BT); the conclusions of that group are contained in WD-13. WD-13 notes that TBR-21 is technically flawed and should be fixed quickly. It is primarily deficient in the lack of sending level limits above 200 kHz. Liaisons were drafted to TRAC (Technical and Regulatory and Approvals Committee responsible for pan-European approval of TE) and the ETSI Board to determine whether a new TBR is required for DSL. HDSL (HIGH-RATE DIGITAL SUBSCRIBER LOOP)
ISDN TRANSPORT After some periods of instability, the HDSL document (issue 5 of TS 152) is finally stable. TD-52, Request for Clarification of Subclause 7.7.3.2 (C. Heidelberger, Schmid Telecom AG), gives a minor editorial comment concerning the application of the scrambler only to the ISDN bits and not to synchronization and to the justification bits. With this agreed modification, the issue 5 of now TS 101 135 will go to TM for approval and publication. S. Schmoll (Alcatel) indicated that the ITU Recommendation G.991.1 on multi-pair HDSL, based on TS 101 135, is likely to be approved at the October SG15 meeting. WD-21, the Living List of HDSL, has therefore been closed after six years of work. HDSL2 A T1E1.4 working draft of the HDSL2 Standard from ADC Telecommunications was tabled as WD-07; no discussion took place on this document, which is not on the present list of work items of TM6. ANAI (ACCESS NETWORK ARCHITECTURE AND INTERFACES) Two work items are assigned to ANAI: RTR/TM-03075, Broad-band access digital section and NT functional requirements (Rapporteur, A. Profumo) REN/TM-03086, Cell based UNI for 155 Mbit/s and 622 Mbit/s/s (Rapporteur, P. Battistello) It is assumed that another work item will be phasing out DTS/TM03024 revisions to TS 101 272 (Requirements of Optical Access Networks for evolving services). WD-16 gives part of the preceding meeting (May, 1998) report. B. Orth (DTAG), coordinator of ANAI, presented the report of ANAI activity (Vienna Sept. 21-25, 1998) in WD-17.
TS 101 272, REQUIREMENTS OF OPTICAL ACCESS NETWORKS FOR EVOLVING SERVICES TD-6 (S. Webster, NEC) is the second version of items for the possible revision of TS 101 272 V1.1.1 (the former DTS/TM-03024). Agreements reached at the final TM3 meeting in Sophia Antipolis, May 1998, have been incorporated. At the last meeting of the FSAN OAN group, a document with the required editorial changes to the draft recommendation G.983 (G.983.1, G.PONB for ATM-PON System) was provided for the next ITU-T SG15 meeting in October 1998. TD-9, Proposals for the Living List of TS 101 272 (I. Marlow, Deutsche Telecom AG), provides a part of the ITU-T document, including all those changes which had not been submitted to ETSI before this meeting. The remaining part of the ITU-T document was already incorporated in TS 101 272 during the TM approval. In sum, these changes are to maintain alignment of G.983 and TS 101 272.
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REN/TM-03086 (REVISION OF ETS 300 299) TD-7, Simulation result on the simplified mechanism proposed for DSS synchronization process (P. Battistello, FranceTelecom-CNET), was presented for information. It provides simulation results based on real implementation for the simplified DSS synchronization mechanism which was proposed in ETSI TM3 Bern meeting (TD-02) and which is still in the Living List as “Under Study.” These simulation results confirm the theoretical analysis detailed in previous contribution.
TD-8, ANAI Technical Comments on ETS 300 299 (P. Battistello, FranceTelecom-CNET), addresses three technical points that should be clarified during the next revision of ETS 300 299. These technical points are: 1) Applicability of HEC (header error control) single bit error correction mode (§10.3.1) 2) HEC regeneration and header scrambling (§10.5.3.3) 3) Automatic scrambling detection (§10.5.3.3) WD-20 includes for information the latest text of the ITU-T I.432.1 Recommendation. BROAD-BAND ACCESS DIGITAL SECTION AND NT FUNCTIONAL REQUIREMENTS (DTR/TM-03007) TD-18, Proposed Methodology for xDSL NT1 Functional Specification (R. Boden, Philips), suggests a possible way to specify NT (Network Termination) functionality by using a functional modeling approach; this specification method is based on functional decomposition of the equipment into atomic functions. The equipment is then described by its P2S Equipment Functional Specification which lists the atomic functions, their interconnection and any overall performance objectives. WD-18 is the reply to WD-1 received from ADSL, which accepts that the final version of the TR shall include comments regarding VB56 usage, F4 flows, and the inconsistency to route a single path via different links. The following were presented for information: WD-11 (NEC, Functional architecture for xDSL Dual Latency) WD-14 (Nortel to the ADSL Forum, a simple device protocol) WD-15 (Nortel to the ADSL Forum, a new NT type between NT1 and NT2) MISCELLANEOUS TD-20, Application of DTM in Access Network (M. Meninger, SPT TELECOM), summarizes basic properties of a new transfer mode (DTM [Dynamic Transfer Mode]) and asks if TM6 should consider its applicability in access network. The forthcoming ANAI meeting will be held the last week of November. J. Besseyre (Consultelecom) asked if the ANAI meeting might be not be held in Sophia Antipolis at the same time as the SDSL/VDSL meeting, 24-27 November, 1998; since ANAI is now part of TM6, some delegates agreed that it should meet at the same time to profit from the synergism between the former TM3 and TM6 and to avoid unnecessary travel. SDSL The SDSL session was chaired by S. Schmoll (Alcatel). S. Schmoll highlighted first the difference between the US requirements and the European operator-expressed requirements in terms of transport of ISDN, reach, remote powering, latency, and power available/needed to/by the SDSL equipment. The operator requirements are dealt with first. • TD-51, Functional Requirements for SDSL (C. Pellicer Losato, Telefonica), expresses Telefonica’s functional requirements. It suggests that narrowband services (e.g., telephony) should be transported in the digital core frame to avoid the requirement for a splitter and that remote power feeding should be optional. • TD-45 (L. Tempestilli, Telecom Italia and L. Magnone, CSELT) indicates the requirements for SDSL seen by Telecom Italia; the existing solutions for HDSL (2B1Q and CAP) should be investigated first before looking into new modulation solutions. • TD-37, Further Requirements on SDSL (T. Stefansson, Telia Research AB), presents their requirements based on a target application of SOHO IP applications. • WD-08 presents a late contribution on the requirements for SDSL as seen by France Telecom. It suggests reach of 4.5 km at 384 kbit/s and 3 km at 2.048 mbit/s on 0.4 mm wires.
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Once those later requirements were known, as well as some changes expressed by BT, the discussion concentrated on TD-4, Requirements for a SDSL Transmission System (S. Schmoll, Alcatel): Five operators (BT, Deutsche Telekom, Finnet Group, PT Austria, and Telia) presented a list of their requirements for a SDSL transmission system. These requirements are taken from the report of the Luleå meeting, sub-clause 4.4. A lengthy discussion took place; the most controversial topics were splitter versus in-frame transmission of the POTS/ISDN services, need for remote powering of the “lifeline” service, and of the SDSL modem in part or in totality. “Range is more important than bit rate.” Bit rate is defined as the actual data rate available to the SDSL data user. It does not include the overhead for framing, signaling and management and may be quite different for splitter vs. non-splitter solutions. The SDSL user data bit rate does not assume any baud rate on the line. As a result of this discussion, there were a few conclusions agreed by all delegates, contained in WD-24: • Data bit rate 384 kbit/s/s to 2.304 kbit/s/s • Reach of 3 kms at 2.048 kbit/s/s and reach of 4.7 kms at 384 kbit/s/s (same reach as basic rate ISDN) • Granularity nx64 kbit/s (user bit rate) • A management channel (which may be a logical channel) is needed with a bit rate of up to 64 kbit/s • No handshaking; no rate adaptation but fixed rates at installation time. Items for further study are: remote powering numbers (POTS power) and splitter vs. in-frame solutions. TD-25, Central Office Powering for SDSL (M. Sorbara, GlobeSpan), describes some power budgeting guidelines for SDSL system dissipation supporting lifeline applications via the NTU. To provide the associated lifeline service for the voice channel, the NTU (network termination unit) would need to be powered from the central office. Depending on the power dissipation of the components in the NTU, the reach of SDSL may be limited by either NTU power dissipation or core modem transmission capability. This contribution recommends that power budgeting be incorporated in the SDSL report. As a result of this TD, an ad-hoc group was formed; the conclusions are given in the full meeting report and in WD-19. WD-19 contains conclusions that were not agreed by some delegates and that are different from the conclusions reached by the ad-hoc meeting. Operators are invited to contribute on the power needs of a POTS telephone; the figure of 450 mW seems overoptimistic. TD-39, Remote Powering (M Kempe, Siemens) addresses the issue of remote powering in SDSL. Its conclusions come very close to TD-25 and were also considered by the ad-hoc group on powering budget. TD-26, Customer Premises Wiring for SDSL (M. Sorbara, GlobeSpan) describes various premises wiring scenarios. One of the key requirements for SDSL is to simultaneously provision a data channel along with either a telephone or ISDN channel. If SDSL service is to be provisioned in the residential environment (for either business or consumer applications), then the impact on premises wiring must be considered. This contribution recommends that premises wiring be included in the Living List and in the SDSL report. TD-12, SDSL: POTS Splitter Considerations (A. Carrick, Ascom AG), proposes various items for addition to the Living List for SDSL for further study, based on the results of laboratory tests of simple proof-of-concept POTS splitters tested with existing TS 101 135 HDSL systems. While most operators initially had put in their requirements of no splitter and imbedded transmission, this presentation asks the questions in terms of performance and challenges the actual requirements for no-splitter operation. For maximum reach at minimum power, the POTS splitter band offers excellent SNR (Signal to Noise Ratio) which cannot be easily recovered elsewhere in the spectrum. TD-38, Capacity and POTS Splitters (M. Kempe, Siemens), shows that, from a capacity point of view and for both PAM (Pulse Amplitude Modulation) and CAP/QAM (Carrier-less Amplitude Modulation Phase Modulation/Quadrature Amplitude Modulation) modulation formats, there is a clear advantage in carrying POTS in a digital form via in-band transport rather than using an analog form via a POTS splitter. TD-30 on mixed crosstalk issues from Lucent and Cicada Semiconductor was postponed to the next meeting because it proposes line coding considerations. It notes that ANSI T1E1.4 chose the OPTIS (Overlapped PAM Transmis- sion with Interlocking Spectra) line code for HDSL2. TD-3, SDSL Spectral Compatibility Issues (A. Carrick, Ascom AG), presents a summary of the signal spectra that could be expected in the access environment, and illustrates the possible cross-talk into SDSL. The artificial shaped noise model used previously to represent crosstalk in the local network is inadequate for this new environment, and a new test noise model must be developed. It should be based upon an agreement as to the other systems with which SDSL is expected to share the network, and the amount of performance degradation that existing systems can tolerate when SDSL is added to the network. While this presentation was well received, some delegates felt that it gives an unfair representation of the actual OPTIS performance in a European environment.
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TD-10, SDSL: Baseline Proposals for Performance Requirements (A. Carrick, Ascom AG), presents proposals for baseline performance requirements as a starting point for the design of the new optimum line code for SDSL. It pre- sents performance curves for the HDSL systems of TS 101 135, and it proposes that the new optimum SDSL system should be designed to outperform the first generation HDSL systems by the order of 6 dB, with an additional 4 dB improvement gained by optimizing the test noise. TD-11, SDSL: Proposed Requirements for Bit Rate Granularity (A. Carrick, Ascom AG, Study Point 3 of the Living List for DTS / TM-06011-1, Functional requirements for SDSL), proposes a bit rate granularity of n x 128 kbit/s for SDSL systems. This contribution is based on the analysis of existing HDSL systems, although a granularity of n x 256 kbit/s should be for further study for line rates exceeding 1536 kbit/s. While this contribution was well received by the manufacturers, the operators seemed to keep their requirement for a granularity of n x 64 kbit/s. TD-43, Noise Model Wish List for SDSL Performance Test (R. Van den Brink, KPN), provides a wish list of information required to generate a comprehensive noise model for the SDSL tests. The contribution uses the existing VDSL noise specification and points out areas that need to be investigated. WD-27 provides a copy of the foils presented by R. Van den Brink in relation to the content of TD-27, presented in the VDSL discussion but also applicable to SDSL. LIVING LIST The following Living List (WD-25) was established by the rapporteur: SP1-1 Functional requirements SP1-2 Investigation of an optimal line code SP1-3 Rate Adaptation SP1-4 Asymmetric transmission methods SP1-5 Creation of an appropriated noise model SP1-6 Network Termination functions of sub-channels (new) SP1-7 Feasibility of defining a suitable reference point MIB (new) SP1-8 Management of link failure (new) SP1-9 Power budget for remote power feeding (new) SP1-10 Transport of narrow-band signals (new) SP1-11 POTS premises wiring considerations (new) Even though the noise model for SDSL is not yet defined (see discussion on VDSL, below), contributions are invited on transmission and electrical characteristics. ADSL
COEXISTENCE WITH ISDN TD-5 (G. Rose, ETSI Secretary) contains results and comments from TM6 approval for DTS/TM-06006 (ADSL: Coexistence of ADSL and ISDN BA on the same pair and ADSL extended bit-rates). In order to achieve consensus, the rapporteur and the TM6 Chair asked to resolve the “no” vote from BT (British Telecom). A new point was added to the ADSL living list to study the ADSL performance on test loops. The TM delegates also decided to open a new work item to issue a new document corresponding to the new T1E1 ADSL issue 2 document. A discussion followed as to which document should be the base for ETSI’s new document: G.lite, T1E1, or UAWG documents, none of which are compatible with each other. The T1E1 document was agreed to be the base for any new ETSI document. TD-49 (P. Reusens, Alcatel) suggests corrections to some of the time-outs in the diagrams; the corrections were accepted for the ADSL over ISDN document. TD-47, Definition of the C-TONE for ADSL over ISDN (P. Reusens, Alcatel), was accepted. The sets of tones used in ETSI TM6 DTS/TM-06006 do not include the C-TONE (defined in ANSI T1.413 issue 2 for ADSL above POTS). Within G.dmt, C-TONE disappears completely, because it is replaced by G.handshake (G.hs). However, in the (unlikely) case that a purely tone-based activation of the ADSL over ISDN is defined, we still need to define C- TONE. The proposal is to put it on tone 82, which is an even carrier, and not a multiple of 8. (Multiples of 8 are now accepted for the carriers used by downstream in G.hs for G.dmt.) A new study point was added to the ADSL Living List and a note in the document will be added.
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WD-10 and TD-48, Safety of ADSL above POTS or ISDN according to IEC 950 (P. Reusens, Alcatel), raises the issue that when one adds the DC voltage, the ISDN voltage, and the ADSL voltage, one comes out with a voltage across the line which exceeds the IEC limit of 120V. According to the (rigorous) interpretation of the IEC 950 regulations, the sum of all signals of the telephone line must be considered “dangerous”, when the ISDN battery (nominally above 90 V DC) and both the ISDN and the ADSL AC signals are present on the line. It appears that the IEC 950 regulation is not aware of xDSL technology and is applying unnecessarily strict rules. It seems necessary to study the safety of the xDSL products in the IEC and to specify new rules for these xDSL cases above ISDN. One delegate from Alcatel Germany is attending the IEC conference in Toronto and this establishes an informal link to IEC; S. Schmoll (Alcatel) will inform TM6 delegates of the result of that discussion in the forthcoming meeting of TM6. TD-46, Framework Proposal for Revision of ETSI ADSL Technical Specs (L. Magnone, CSELT, rapporteur of ADSL), proposes a revision to ETR 328 (ADSL technical report based on T1.413 issue 1) as well as a revision to the just approved TS-06006 (Asymmetric Digital Subscriber Line (ADSL) - Coexistence of ADSL and ISDN BA on the same pair and ADSL extended bit-rates [revision of T1.413]). TM6 delegates agreed to create a new work item (European-specific ADSL requirements based on ANSI T1.413 issue 2) to be drafted by G. Rose (ETSI Secretariat). This is contained in WD-26 and was approved by TM6. All other work items in ADSL are closed. TD-50, G.lite: bit-swap (P. Reusens, Alcatel), states that different standardization bodies are involved in the G.lite variant of ADSL; in G.lite bit-swap is proposed but is not yet agreed; technically, bit-swap is judged a necessary el- ement in protecting DMT transmission against varying noise sources. This contribution presents its technical merits and encourages European manufacturers and operators to endorse bit-swap, to make it mandatory in any ETSI document and to vote in favor in the ITU-T. The meeting agreed that bit-swap should be mandatory in Europe; individual members are asked to contribute into the ITU-T. (See also the discussion on bit swap in the WP1/15 report in this issue of CSR-T.) TD-27, Proposal for SDSL performance tests (R. Van den Brink, KPN), is a detailed proposal for test loops, noise models and test requirements on SDSL. The framework of this text is mainly based on the VDSL performance tests, but dedicated to the SDSL frequency band. It enables well-defined performance simulations on SDSL to support the future definition of realistic SDSL requirements such as spectral masks, bit rates, loop length, etc. While TD-27 was presented in the ADSL session and the VDSL session, it also applies to SDSL. The TM6 chair proposed to make an ETSI Technical Report out of this document; however, R. Van den Brink did not agree to become the rapporteur for this ETR, so TD-27 will become a permanent TM6 document instead; this vital document needs to have inputs for SDSL which are encouraged for the forthcoming TM6 meeting. The set of foils that were presented, which are somewhat different from the content of TD-27, were tabled as WD-22. VDSL This VDSL session did not have any document for approval. B. Waring, rapporteur for VDSL, asked delegates for more participation between meetings so as to move the work faster. The session consisted of a presentation of most of the contributions and a discussion on how to advance the VDSL specification. TD-34, TC Sublayer-ATM Transport Protocol Specific TC (V. Oaxman, Lucent technologies for VDSL Coalition), proposes a specification of the ATM Transport Specific Transmission Convergence sublayer (ATM-TC) which de- scribes the ATM-based service transmission over VDSL system. This document defines a minimum set of requirements to deliver an ATM service from the ONU to the customer premises. TD-41, ATM-TC for VDSL (L. Humphrey, Nortel/Bay Networks), outlines an ATM TC for VDSL which accommodates power saving and crosstalk saving modes by allowing the transmitter to enter a low power state during transmission of idle cells. This proposal was not yet accepted by the VDSL Alliance and may be subject to reconsideration if dynamic power saving becomes relevant. TD-33, VDSL Payload Rates for Symmetric Services (V. Oaxman, Lucent technologies for VDSL Coalition), proposes a new set of payload bit-rates for performance evaluation of VDSL link transporting symmetric services. The document is based on previous contributions to TM6. The new definition of evaluation rates provides an effective usage of VDSL payload for symmetric services, the main component of which is SDH. The proposed approach is independent of the line coding and of the modulation technology. TD-40, VDSL Frame-OAM and Narrow-Band Service Delivery (L. Humphrey, Nortel), proposes a format for a generalized clear Embedded Operations Channel (EOC) channel which supports transmission of network timing refer- ence and maintenance indicator bits. The method also supports the in-band transmission of n x 64 kbit/s telephony
48 Vol. 9.8 Copyright © CSR 1998 November-December 1998 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS channels and multiple plesiochronous independent streams. TD-40 was accepted as input to study points SP1-14 and SP 1-20. TD-28 (K. Jacobsen, Amati/TI) is the latest draft of the VDSL Alliance’s DMT proposal for VDSL. The proposal specifies both a time-division duplexed (TDD) and frequency-division duplexed (FDD) system. In both cases, compliant modems support both symmetric and asymmetric transmission. Support of 1:1, 2:1, 3:1, 4:1, 6:1 and 8:1 transmission is mandatory, as is rate adaptivity at start-up. Support of ATM is also required. TD-28 is to be incorporated into the draft of TM 06 003-2.
TD-31 (V. Oaxman, Lucent technologies for VDSL Coalition) proposes line coding, modulation and duplexing methods for VDSL systems using single carrier technologies (CAP and QAM). It specifies a PMD sub-layer for both NT and LT which complies with the VDSL system requirements as specified in DTS/TM-06003-1. The proposal supports all the ETSI downstream rates with either symmetric or asymmetric upstream rates. The proposed coding and modulation methods provide full interoperability between CAP and QAM transceivers. This document was accepted for draft TM6 003-2. TD-32 (V. Oaxman, Lucent technologies for VDSL Coalition) proposes a specification for the VDSL transmission frame format, frame delineation algorithm, randomization and FEC methods. The proposed frame format optionally contains Fast and Slow virtual data channels and provides both for single and dual latency operations. The transmission frame header bears frame alignment, NTR and control information. The proposed methods are independent of the line coding modulation technology. This document was accepted for draft TM6 003-2. TD-17 (K. Foster, BT) summarizes the progress in resolving the following VDSL Living List items : SP1-1, SP1- 2, SP1-20, SP2-9. It collates the e-mail discussion which has occurred since the last TM6 meeting and makes some proposals to progress the work. TD-13, Editor’s report on the ANSI VDSL System Requirements (J. Cioffi, Stanford University, Editor for the VDSL ANSI) attaches Rev 16a of the ANSI VDSL System Requirements. It differs from the Rev 16 official liaison only in the correction of some typographical errors found after the San Antonio meeting and posted on the T1E1.4 web page. Also included here for information is the editor’s summary of differences with ETSI TM6 Phase I technical report for VDSL. These are probably of a nature that a single implementation could be designed that will comply with both specifications. TD-14, Mixed Loading for Splitterless DSL Operation (J. Cioffi, Stanford University), describes a method for recovering from abrupt line changes, like off-hook impedance changes in splitterless operation, without service dis- ruption. The method allows a guarantee of a fixed high-quality continuous service on the line that is augmented by a rate-adaptive non-guaranteed data rate. This method would allow the option of not using any fast-training in splitterless DSL operation, thus preserving quality of service for DSL even when operating without splitters. TD-15, Further Results on Peak-to-Average Ratio Reduction (J. Cioffi, Stanford University), shows that if PAR reduction is done on these Nyquist rate samples, the PAR of the continuous time wave form can increase signif- icantly, but if we extend the tone-reservation and tone-injection algorithms to reduce the PAR at twice the Nyquist rate, the continuous time PAR can be efficiently reduced. Moreover, for the tone-injection method we can extend our previous algorithms to include the effects of the transmit filter, which leads to PAR reductions of more than 5 dB at the AFE input. TD-16, Mitigation of DSL Crosstalk via Multi-user Detection and CDMA (J. Cioffi, Stanford University), presents fundamentals of multi-user detection and multi-user information theory to suggest that the current DSL approach to modeling and specification of DSL spectral compatibility are overly pessimistic. Some examples and fundamental information-theoretic results suggest that crosstalk can be substantially mitigated without coordination or access to inputs or outputs of crosstalking pairs, depending on the level of background additive white Gaussian (AWG) noise. TD-19, A Request for Clarification from the Telcos on the VDSL Requirements (M. Kempe, Siemens/Savan), raises five issues for clarification of the requirements as part of the feedback from the equipment suppliers to the Telcos, prior to the definition of Part 2 of the VDSL specification. TD-21, Throughput of Short Range VDSL Services (A. Kliger, Metalink), corrects the results of a former contribution. The former contribution considered the transport of S3 with transmitted mask M1. This contribution take the slow decline of mask M1 between 10 MHz and 20 MHz into account. It also considers a flat PSD mask of -70 dBm/Hz and -75 dBm/Hz between 10 and 20 MHz. It concludes that with those modifications, the performance of S3 and S4 services are improved significantly.
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TD-42, Specification of crest distribution mask for noise in performance test (R. Van den Brink, KPN), states that the current VDSL performance test puts insufficient requirements on the nature of the noise signals to be used in the performance test. It proposes to use a mask for the crest distribution function of the test noise. As the shape of the mask is not yet defined, this document did not convince all delegates. TD-35, Achievable bit rates with the constant power back-off method (T. Kessler, DTAG), notes that the achievable upstream bit rates of VDSL with NTs distributed along a cable have been calculated for different maximum distances. For a maximum distance of 1.5 km, a bit rate of 13 Mbit/s upstream and 13 Mbit/s downstream cannot be achieved with FSAN-noise and constant power back-off. The required dynamic range depends on the maximum distance and the reference frequency. It is suggested that only a management system can set optimal power back-off for all VDSL systems within a cable. TD-17 from the Luleä meeting describes various power backoff methods to reduce the effect of FEXT coupling from short lines into long lines in the distributed cable topology. The contribution examined three alternatives. TD-29, Proposal to Use Frequency-Dependent Upstream Power Backoff (K. Jacobsen, Amati/TI), examines the implementation complexities of the constant power backoff and reference length methods. It concludes that the reference length method should be used by VDSL systems to maximize performance. TD-29, together with TD-35, was added to study point 1-18 of the VDSL Living List. TD-36, VDSL Deployment, Services, and Customers, Part 2: Shared access with flexible symmetry (D. Bengstrom, Telia Research AB), introduces the fact that customer initiatives regarding VDSL deployment reveal potent niche- markets for VDSL and raise technical issues as well. The concept of “Shared access” business case is discussed, as well as the corresponding network structure and the requirements it puts on VDSL. The new application is a building LAN shared among several tenants and communicating with the outside building world through VDSL. TD-36 was added to the Living List study point 1-20 and was sent to ADSL Forum as a liaison (WD-28). TD-44, Noise model Wish List for VDSL Performance Test (R. Van den Brink, KPN), addresses the information that is required to complete the VDSL noise model. Although much progress has been made, there are still areas where operator input is required to generate a noise model that is representative of the VDSL reality. As a result of these contributions, the VDSL Living Lists (for part 1 and part 2) will be updated; some study points will be deleted due to lack of contributions. Jacques Besseyre, Consultelecom
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50 Vol. 9.8 Copyright © CSR 1998 November-December 1998 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF WORKING PARTY 1/15, NETWORK ACCESS OCTOBER 12 – 23, 1998 GENEVA, SWITZERLAND The Working Party 1/15 (Network Access) chair is A. Nunn (UK). COM 15-R 9 is the previous meeting report. TD-38(PLEN) is the report of this meeting. TD-40(PLEN) is the status of the WP1/15 Recommendations. TD-41(PLEN) contains the liaison statements sent from this meeting. The Working Party proposed the ITU TSAG a new standardization area, Access Networks, and requested the TSAG allocate an appropriate code (TD-41(PLEN), WP1/15 liaisons, Annex 12). The questions currently allocated to WP 1/15 are: Q Title Rapporteur 1/15 Access Network Transport R. Feigel, Bosch 2/15 Characteristics of Optical Systems in Local Access Networks T. Finegan, BT 3/15 DCEs for Digital Leased Circuits G. Sebek, France Telecom 4/15 DCEs for Subscriber Access Systems R. Stuart, 3Com TD-51(WP1/15) contains proposed revisions to the Questions in WP1/15. The titles and text of Q2/15 and Q4/15 were revised to reflect the requirements of networks optimized for the transport of IP and IP-based services. The new titles are: Q2/15 Characteristics of Optical Systems in Local Access Networks for Transport and Distribution Q4/15 Transceivers for Subscriber Access Systems The text of the revised Questions is in TD-72(PLEN). WP1/15 RECOMMENDATIONS APPROVED AT SG15 Q Approved Recommendations Document(s) 2/15 G.983.1, G.PONB for ATM-PON (Asynchronous Transfer TD-26(PLEN 2/98), TD-39 Mode - Passive Optical Network) System (WP1/15 2/98) + COM 15-110 4/15 G.991.1 (G.hdsl) High Bitrate Digital Subscriber Line (HDSL) TD-38(PLEN 2/98) + COM 15- Transmission System on Metallic Local Lines 123
Table 1. Recommendations Approved (Decided) at Working Party 1/15, October 1998. WP1/15 RECOMMENDATIONS DETERMINED AT SG15 Q Determined Recommendation Document(s) 3/15 V.300, ex V.144K, A 144 kbit/s Data Circuit Terminating Equipment TD-43 (PLEN) Standardized for Use on Digital Point-to-Point Leased Circuits 4/15 G.992.1 (G.dmt) Asymmetrical Digital Subscriber Line (ADSL) Transceivers TD-44 (PLEN)© 4/15 G.992.2 (G.lite) Splitterless Asymmetrical Digital Subscriber Line (ADSL) TD-45 (PLEN)© Transceivers 4/15 G.994.1 (G.hs) Handshake Procedures for Digital Subscriber Line (DSL) TD-46 (PLEN)© Transceivers 4/15 G.995.1 (G.ref) Overview of Digital Subscriber Line (DSL) Recommendations TD-47 (PLEN)© 4/15 G.996.1 (G.test) Test Procedures for Digital Subscriber Line (DSL) Transceivers TD-48 (PLEN)© 4/15 G.997.1 (G.ploam) Physical Layer Management for Digital Subscriber Line TD-49 (PLEN)© (DSL) Transceivers Table 2. Recommendations Determined at Working Party 1/15, October 1998. Q1/15, ACCESS NETWORK TRANSPORT The Question 1/15 Rapporteur is R. Feigel, (Bosch, Germany). The agenda is TD-23(WP1/15). The report on the interim activities prior to this meeting is TD-21(WP1/15). TD-33(WP1/15) is the report of Q1/15 from the SG15 February 1998 Meeting. TD-35(WP1/15) is the list of input documents at this meeting. No interim meetings are scheduled.
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ANT STANDARDIZATION The feedback received from the various Standardization Groups to whom the initial draft of ANT (Access Network Transport) Standardization (TD-17 WP1/15)) was sent for comment, additions and contact has been positive and constructive. The feedback was incorporated into the final draft of the Standardization Plan, which was completed at this meeting of SG15. TD-54(PLEN) provides the ANT model, ANT scenarios (including wireless, satellite and cable) and an extensive overview of existing standards activity. An initial draft of the Work Plan was also prepared (TD-55(PLEN)) and should be further developed. The Work Plan continues coordination and liaison with other standards bodies to maintain the Standardization Plan. TD-18(WP1/15) (R. Feigel, Bosch Telecom) is a table of ETSI radio related Standards for inclusion in the Standardization Plan. TD-19(WP1/15) (R. Feigel, Bosch Telecom) contains a table of Standards from several bodies (mostly ITU-R) for inclusion in Standardization plan. With the completion of the Standardization plan covering the work of both the ITU-T and ITU-R, Q1/15 plans to establish contact with the relevant external standards bodies so that details of their standards can be incorporated into the plan. Both the ANT Standardization Plan and Work Plan will be “living” documents, since they will require continued updating. Hence it is envisaged they will be published in the COM 15-R series of documents. TD-20(WP1/15) (R. Feigel, Bosch Telecom) is a proposal for a web-based ANT Standardization Plan. Once the presentation methodology for these documents is finalized, it is hoped that the Standardization Plan and the Work Plan will be migrated to a web site. TD-18(PLEN) (Chair, WP1 SG15) reports activities and achievements of Q1/15 as the core Question supporting SG15’s role as Lead Study Group for ANT. It reflects the objectives for this meeting. INPUT DOCUMENTS TO Q1/15 REGARDING THE ANT STANDARDIZATION PLAN TD-1(GEN) (ICG for IMT-2000, R. Blane, Inmarsat) reports on the progress of the Intersector Coordination Group for IMT-2000. The list of Standards in this liaison was incorporated in the ANT Standardization Plan, A2.3. This list has to be revised, as not all listed Standards seem to belong to ANT. TD-6(GEN) (ITU-T SG4, M. Klerer, AT&T) is a proposal for integrated management of telecom networks and IP networks. SG4 notes its responsibility in GII for integrated management of telecommunication networks and IP networks. The issue was incorporated in the ANT Work Plan as well as the Standardization Plan. TD-13(GEN) (ITU-R WP 9B, Y. Schifres, TRT Lucent) is a liaison that notes the responsibility of WP9B for technical studies on Fixed Wireless Access (FWA) and points to a first revision of the Hybrid Fiber Radio Recommendation ITU-R F.1332. The Recommendation was added to the Standardization Plan; a liaison with the attached new ANT Standardization Plan was sent as a reply (TD-41(PLEN) Annex 2). TD-16(GEN) (ITU-T SG4, D. Sidor, Nortel) notes that SG4 as the lead Study Group for Telecommunications Management Network (TMN) has installed a Project Management Team (PMT) for TMN. A list of TMN-related Recommendations is included. Q1/15 asks in a liaison reply (TD-41(PLEN) Annex 3) if they would prepare a list of ANT-related TMN documents for inclusion in the ANT Standardization Plan. TD-3(WP1/15) (ITU-T SG5, J. Erreygers, Raychem) contains a well-prepared table of K.series Recommendations for inclusion in the ANT Standardization Plan. A reply (TD-41(PLEN) Annex 6) with the ANT Standardization Plan attached was sent asking for further contact. TD-6(WP1/15) (ITU-T SG12, C. Dvorak, AT&T) confirms SG12’s expertise on transmission delay and echo control and proposes the inclusion of G.114 and G.131 in the ANT Standardization Plan. A liaison (TD- 41(PLEN) Annex 7) with the ANT Standardization Plan attached was sent back asking for further close cooperation. TD-8(WP1/15) (ITU-T SG13, T. Kent, BT, R. Townsend, Lucent, Y. Maeda, NTT, and D. Cooper, Nortel) is a liaison that contains several comments and suggestions from various Questions in SG13 on the ANT Standardiza- tion Plan, especially on the use of the interface point XNI between access and customer premises networks. Some issues like the presentation of the scenario figures need further consideration. A liaison (TD-41(PLEN) Annex 11) was sent back asking for further close cooperation; it notes that the ANT Standardization Plan is a living document.
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TD-11(WP1/15) (ITU-R WP 8A, J. Costa, Nortel) gives information about the task of a JRG of WP8A and WP9B. Attached is a draft on “Performance and availability requirement an objectives for FWA” and a list of frequency band allocations used in several countries. Both issues were added to the ANT Work Plan and the Standardization Plan. A liaison (TD-41(PLEN) Annex 14) was sent back containing the new Standardization Plan and asking for further close cooperation. TD-12(WP1/15) (ITU R Task Group 8-1 J. Costa, Nortel) notes that Task Group 8-1 is working on radio aspects of IMT-2000; they consider the IMT-2000 radio interface as equivalent to the XNI (Customer Network Interface) in the ANT model, and the Radio Access Network (RAN) interface to the SNI (Service Node Interface). A list of relevant M.series Recommendations is recommended for inclusion into the ANT Standardization Plan. The Recommendations were included in the plan, and a liaison (TD-41(PLEN) Annex 8) was sent back asking for further cooperation. TD-13(WP1/15) (ITU-R Task Group 8-1 A. Kumar, Telecommunications Engineering Centre) contains a working document on “proposed FWA (Fixed Wireless Access).” The issue of FWA was added to the ANT issues list in the ANT Work and Standardization Plan. A liaison (TD-41(PLEN) Annex 9) was sent back asking for further cooperation. TD-14(WP1/15) (ITU-T SG9, R. Catchpole, Nortel ) gives comments and information in the field of CATV (Cable Television). It proposes the inclusion of J.112 (Transmission systems for interactive cable television systems) and other Recommendations in the Standardization Plan. The Recommendations were included, J.series Recommendations references were updated, and a liaison (TD-41(PLEN) Annex 1) was sent back asking for further cooperation. TD-16(WP1/15) (ITU-R JRG 8A-9B, Y. Schifres, Lucent) informs Q1/15 of the JRG 8A-9B’s work on a new analog user/network (UNI) interface for FWA. A draft of the electrical requirements is attached. The issue was in- cluded in the ANT Work and Standardization Plan; a responsible SG in ITU has yet to be identified. A liaison (TD- 41(PLEN) Annex 2) was sent back. An ETSI draft has been identified dealing with this issue. TD-36(WP1/15) (ITU-T SG16, L. Brown, Motorola) notes the approval of Recommendation V.90, defining modems for Internet access. V.90 has been included in the ANT Standardization Plan. A liaison (TD-41(PLEN) Annex 10) was sent back asking for ongoing cooperation; the new ANT Standardization Plan was attached. TD-17(PLEN) (SG15 representatives to ICG IMT-2000) reports of the third meeting of ICG IMT-2000. The issue of standardization of satellite transmission-related access networks was added to the issues list in the ANT Work and Standardization Plan. ADDITIONAL INCOMING DOCUMENTS AND LIAISONS TD-1(PLEN) (ITU-T SG2) contains a questionnaire on the Year 2000 Millennium Compliance. It was provided for information. TD-9(PLEN) (ITU-T TSAG, F. Brett, Nortel) contains information for the collaboration between ITU-T and the Internet Society (ISOC) and the Internet Engineering Task Force (IETF). The issue is incorporated in the ANT Work and Standardization Plan. Q1/15 will contact the bodies via their web pages, and results will be reported to TSAG. TD-10(PLEN) (ITU-T TSAG, K. Park, ETRI, Rep. of Korea) informs Q1/15 about the ITU’s pre-publication policy (Recommendations appear on the web 4 weeks after SG approval), the informal FTP areas (IFTP), publication of Formal Language Descriptions, and document submission formats. TD-16(PLEN) (ITU-T SG13) reports the June meeting of Intersector Coordination Group (ICG) SAT. It includes consideration for the future collaboration between ITU-T and ITU-R on satellite matters as well as a work plan related to satellite issues. TD-7(GEN) (SG4, M. Klerer, AT&T, and T. Rutt, Lucent) contains updated information on SG4’s responsibilities for GII projects. TD-12(GEN) (ITU-T SG13, H. Schink, Siemens) contains the allocation of Work on the GII Standardization Projects and their description. Q1/15 covers the Project N.1, Architecture and layer 1 aspects of narrowband/ broadband access infrastructures for GII. TD-2(WP1/15) (ITU-T SG4, A. Gillespie, BT) comments on the presentation of management interfaces in the ANT Standardization Plan and proposes to show clearer distinction between management interfaces and OAM
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(Operations, Administration, and Maintenance) flows which are embedded in the transmission flows between network elements (e.g., the F1, F2 and F3 flows of SDH and the F4 an F5 flows of ATM). Since there is not enough ex- pertise on OAM flows in the group, a liaison (TD-41(PLEN) Annex 13) was sent back asking for further clarification and a suitable diagram. TD-5(WP1/15) (ITU-T SG11, R. Pandya, Nortel) asks for information about updated work schedules in field of IMT-2000. REVISION OF Q1/15 WORKPLAN The updated Q1/15 workplan is in Annex 3 of TD-38(PLEN), the WP1/15 report. There were only minor changes to the Q1/15 Work Plan. Q1/15 will not longer produce Recommendations. The area of related standards was expanded to full services access networks. Some information about the issue of several Standards Organizations was added to Table 1, Phased Approach to ANT Coordination with Critical Organizations. REVISION AND UPDATE OF THE ANT WORK PLAN TD-55(PLEN) is the Access Network Transport Work Plan dated October 20, 1998. The list of contacts was restructured to show all presently known contact persons with names and addresses. Additional/ supplemental contacts will be obtained via correspondence. Results will be reported to the TSB. The list “ANT Issues identified” was expanded. Gaps and open issues were added from the input documents to this meeting and from those identified in the meeting discussions. No progress was made on prioritization, plan for missing standards, and plan for conflicting standards. The liaison tracking list has yet to be updated. The installation of an interactive Web Page for Q1/15 ANT Standardization activities should be pursued in the near future. REVISION AND UPDATE OF DRAFT ANT STANDARDIZATION PLAN TD-54(PLEN) is the Access Network Transport Draft Standardization Plan, dated October 20, 1998. It is based on the draft ANT Standardization Plan from the February 1998 SG15 meeting. All changes –even those of the Tel Aviv interim meeting– are identified by change marks; only the figures of the Scenarios do not show all the change marks. A clean copy will be provided in the Q1/15 IFTP area (ANTPL1098.DOC) The main results from this meeting are • Insertion of the expanded “ANT Issues identified” list from the ANT Work Plan in 6.1.3 • A2.2, a list of Standards not assigned up to this meeting, has been completed, but changes were not incorporated in ANNEX 2.1. Liaisons (TD-41(PLEN) Annex 4 and Annex 5) to ANSI, ATMF, EIA/TIA, ETSI, ADSL Forum, DAVIC and ITU-T SG5 were sent asking for help in revising A2.2 in order to have the correct assignments. • A2.3 was added. It contains a list of all standards which were added in this meeting. A2.3 needs a careful check, to verify whether all listed documents relate to ANT. This check should be done by correspondence. It was agreed to advance the draft ANT Standardization Plant to “Issue 1” status.
Q2/15, CHARACTERISTICS OF OPTICAL SYSTEMS IN LOCAL ACCESS NETWORKS The Question 2/15 Rapporteur is T. Finegan (BT, UK). An interim meeting will be held January 27-29, 1999, in USA (hosted by Lucent Technologies). Recommendation G.983.1, G.PONB for ATM-PON (Asynchronous Transfer Mode - Passive Optical Network) System, was approved (Decided) at the opening Plenary, as TD-26(PLEN 2/98), TD-39 (WP1/15 2/98) + COM 15-110. Following the approval of G.983.1, the Q2/15 objective was to focus on a draft new Recommendation covering the management and control of ATM-PON. Following the review of documents in the WP1/15 plenary, only four documents remained for consideration in Q2/15. TD-6(PLEN) (P. Wery, Nortel) ADSL Forum Request, TD-17(PLEN) (SG15 Representative to ICG
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IMT-2000) Summary of Third Meeting of ICG IMT-2000, and TD-22(PLEN), List of White Contributions, were taken for information; it was agreed that no further action was required. The text of Question 2/15 was reviewed in connection with the transport of IP and some modifications were agreed. The revised text is given in TD-72(PLEN). DRAFT RECOMMENDATION G.983.2 The main focus of the meeting was D.457 (Y. Maeda, NTT), Proposed ONT/NT (ONU [optical network unit] in the FTTH configuration/NT [network termination] in the FTTB, FTTC and FTTCab configuration) Management and Control Interface (omci) specifications for a new draft Recommendation G.983.omci. The experts agreed that the work in the next eight months should concentrate on the development of a draft new Recommendation G.983.2 - “ONT/NT management and control interface specifications.” The target for this draft new Recommendation is Determination at the June/July 1999 meeting of SG15. D.457 provides the initial text to be considered. It was agreed to use this document as a basis for this work and that Y. Maeda (NTT) will be the editor. Some minor editorial items were pointed out in this text and these will be updated. In particular, it was agreed that in Table 6 of this document, the primary rate 2 Mbit/s E1 should be included, consequently Table 9 will be updated with the 2M REC and 2M AIS. The UPC function, which is not included in this document, should be the subject of future contributions. In order to achieve the challenging target of Determination at the next meeting of SG15, an interim meeting will be held January 27-29, 1999, in the USA hosted by Lucent Technologies. At this meeting it is intended to: • Consider the contributions and changes to the clauses in this document; • Agree to a stable document; • Prepare a white contribution for the June/July 1999 meeting of SG15. Although this is a very challenging target, it is essential that this document be available at this stage of the ATM- PON development; it is unlikely to be of benefit a year later. The Agenda for the interim meeting is given in Annex 4 to TD-38(PLEN). The status of the Q2/15 Recommendations included in the WP1/15 Work Plan was reviewed and updated.
Q3/15, DCES FOR DIGITAL LEASED CIRCUITS Because there were no contributions addressed to this Question, it was agreed to deal with any Q3/15 matters during the WP1/15 plenary sessions. The text of draft new Recommendation V.300 (ex V.144k, TD-43(PLEN), A. Nunn) was reviewed; it was agreed to forward it to the SG15 plenary for Determination. This DCE is intended for use on 128 kbit/s (or 144 kbit/s) digital point-to-point leased circuits other than ISDN. The DCE specified includes rate adaption, end-to-end signaling, testing and multiplexing features. However, the line signal and the signaling rate is considered a national matter and is not specified. It was noted that some further editorial work is required on this draft new Recommendation and it was agreed that the Rapporteur would submit a white contribution containing the revised text to the next SG15 meeting.
Q4/15, DCES FOR SUBSCRIBER ACCESS SYSTEMS R. Stuart (3Com) is the Q4/15 Rapporteur. TD-15(WP1/15) is a report from the four Interim Rapporteurs meetings. Three interim meetings were approved for 1999: Jan. 18 - 22, Portland, OR; Mar 29 - Apr. 2, Melbourne, Australia; and May 10 - 14, Boston, MA. TD-40(WP1/15) is the proposed Q4/15 agenda. Recommendation G.991.1, High speed Digital Subscriber Line (HDSL) Transceivers, was approved (Decided) at the opening Plenary, as TD-38(PLEN 2/98) + COM 15-123. Q4/15 agreed to new titles for the Q4/15 Recommendations as follows:
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Rec. No. Rec. Name Recommendation Title G.990 General G.991.1 G.hdsl High Speed Digital Subscriber Line (HDSL) Transceivers G.991.2 Reserved for possible future HDSL Recommendations G.992.1 G.dmt Asymmetric Digital Subscriber Line (ADSL) Transceivers G.992.2 G.lite Splitterless Asymmetric Digital Subscriber Line (ADSL) Transceivers G.993 Reserved for possible future VDSL Recommendations G.994.1 G.hs Handshake Procedures for Digital Subscriber Line (DSL) Transceivers G.995.1 G.ref Overview of Digital Subscriber Line (DSL) Recommendations G.996.1 G.test Testing Procedures for Digital Subscriber Line (DSL) Transceivers G.997.1 G.ploam Physical Layer Management for Digital Subscriber Line (DSL) Transceivers Q4/15 agreed to plan for second generation versions of all Recommendations; the present Editors will maintain the Issues List for the second generation versions, at least until final approval of the present Recommendations. The Rapporteur will select new Editors, as appropriate, for second generation Recommendations. C. Hansen (Intel) indicated he plans to hand over the editorship of G.992.2 after Decision (final approval). INTELLECTUAL PROPERTY RIGHTS (IPR) 32 companies have indicated IP interest in the xDSL G.series Recommendations. All listed below except Lucent have provided notification by either contribution or a letter to the TSB: 3Com Compaq Paradyne Alcatel Fujitsu PC-Tel Altocom GDC Racal Datacom Amati GlobeSpan Rockwell AMD Itex SAS Aware Lucent Stanford Univ. Analog Devices Matsushita Sumitomo Bell Atlantic Mitsubishi Texas Instr. Centillium Motorola VoCAL Tech. Cirrus Logic NEC Siemens AG Cisco PairGain All companies which have made an indication have done so indicating they will be in accordance with 2.2 of the ITU Patent Policy. The Rapporteur reminded the meeting that for those companies which had only provided a contribution, that it was necessary that they also provide a letter to the ITU Director indicating their IP position. NEW WORK ON VDSL, HDSL, AND SDSL D.333C1 (R. Hamdi, Compaq, USA) proposes that SG15 start work on enhancements to G.lite to provide longer loop reach, and higher performance after G.lite is Determined. D.408 (Y. Okamura, NEC, Japan) proposes continuation of the work on Annex C (Japanese TCM ISDN) of G.dmt to reduce latency after G.dmt is Determined. The contributions note a goal of Determination for these follow-on Recommendations in 2000. D.279 (K. Foster, BT, UK) proposes that the work on G.vdsl be deferred until work has progressed in the Regional Standards bodies. D.326 (G. Zedler, Deutsche Telekom) and D.343 (A. Johansson, Ericsson, Sweden) essentially echo D.279. D.330 (T. Starr, Ameritech, USA) proposes that, immediately following the finalization of the present set of Recommendations, work proceed on G.vdsl and G.hdsl2. It recommends that the initial focus be on spectral compatibility, defining international system requirements, and the feasibility of common handshake procedures. D.406 (S. Palm, Matsushita, Japan, representing multiple Japanese manufacturers) essentially echoes D.330. D.328 (G. Zedler, Deutsche Telekom) proposes that work on G.sdsl and G.hdsl2 be deferred until the work has been progressed in the Regional Standards bodies.
During the discussion, BT explained that their concern mainly centered on the availability of enough human resources to track this work in multiple forums. In the end, the Rapporteur ended the discussion by stating that the
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SG15 management team had directed him to proceed with work on these Recommendations. Using this as justification, the Rapporteur obtained the group’s agreement to proceed with the work on G.vdsl and G.hdsl2. Q4/15 agreed to commence work on a VDSL (G.vdsl) and an HDSL2/SDSL (G.shdsl) Recommendation. In making this agreement, Q4/15 recognized the guidance provided by the SG15 management team as presented in Section 6, Guidelines for the meeting of Working Parties, of TD-5(PLEN). Q4/15 determined to take every advantage of the good work already started or published by ETSI TM-6, ANSI T1E1.4, the ADSL Forum and other regional standard groups in regard to this work. This should be done by encouraging the member companies to contribute to the work of the ITU and to encourage close and frequent liaison on the work by each committee. Concerning the timing of this new work however, it is understood by all that Q4/15’s first priority will be to complete the editorial work on the Determined Recommendations at the January 1999 Rapporteurs Meeting. Accordingly, it is not expected that serious consideration of the new Recommendations will be practical until the proposed March/April 1999 meeting in Australia. An initial focus on the International Requirements, on Spectral Compatibility Issues (particularly for VDSL), and the integration/application of G.hs/G.994.1 to these Recommendations was agreed. Q4/15 agreed that liaison person(s) should be appointed to provide improved communications between regional standards groups. This person(s) should carry unbiased communications between the groups and should not therefore hold a position in either group. The Rapporteur requested candidate(s) for such positions. The new Recommendation development work will be conducted under the following designated names: Rec. Name Recommendation Title G.shdsl Single pair High speed Digital Subscriber Line (SHDSL) Transceivers G.vdsl Very high speed Digital Subscriber Line (VDSL) Transceivers
G.LITE C. Hansen (Intel) is the editor of G.992.2, G.lite, Splitterless ADSL Transceivers. D.419 (F. Van der Putten, Alcatel, Belgium) proposes changes to the text of G.dmt and G.lite to bring them into alignment with T1.413. D.284 (G. Sebek, France Telecom) proposes that specific statements should be included in G.lite and G.dmt to clarify that interworking with T1.413 issue 2 is possible. It proposes that this interworking should not require changes to the hardware. Appropriate text will be added to G.ref. D.445 (T. Starr, Ameritech, USA) provides a pointer to ANSI T1.413 Issue 2 for information only. D.467 (R. Townsend, Lucent, USA) proposes that the present text of G.lite be Determined at this meeting. D.334 (L. Brown, Motorola, USA) proposes that the entire suite of xDSL recommendations be Determined at this meeting. D.407 (S. Palm, Matsushita, Japan, representing Multiple Japanese Companies) proposes that the SG15 Determine the present texts for xDSL Recommendations and proceed immediately with work on newer versions. D.325 (R. Hamdi, Compaq, USA) proposes two additional table rows in G.lite. It also provides a simple home wiring model. The group accepted the additional test cases proposed. It was proposed that a section be added entitled “acoustic levels” which would contain the values to reflect the points raised in TD-7(WP1/15) from SG12. This liaison provides guidance from SG12 on acceptable levels of interference from ADSL systems into POTS. After some discussion, it was decided to include this sort of information in either G.lite or G.test. D.420 (F. Van der Putten, Alcatel, Belgium) proposes additional code points (with supporting text) for G.hs (standard information field), G.dmt and G.lite (identification filed); it notes the need to specify how G.dmt and G.lite are supposed to handle information conveyed in G.hs. D.333C1 (R. Hamdi, Compaq, USA) proposes that work immediately start on enhancements to G.lite after Determination of the present text. A question was raised as to whether starting work on the next generation of a Recommendation before it was even approved was in conflict with ITU rules. There was no resolution of this issue. Bit-swap D.281 (F. Van der Putten, Alcatel, Belgium) and D.311 (S. Cascelli, Alcatel, Italy) provide a rationale for making bit swap mandatory in G.lite. They claim the benefits of improved performance and more reliable fast-retrain operation. D.337 (G. Joncour, FranceTelecom) supports the position in D.281.
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D.327 (G. Zedler, Deutsche Telekom) reports that the majority of ETSI members would require that bit-swap be made a mandatory requirement in European implementations. D.338 (A. Johansson, Ericsson, Sweden) and D.430 (R. Feigel, Bosch, Germany) support the position in D.327. D.331 (T. Starr, Ameritech, USA) proposes that bit-swap be made optional in G.lite. D.431 (R. Venkatraman, Silicon Automation Systems, India) proposes that bit-swap be made optional. Opponents of mandatory bit-swap based their arguments on the premise that the protocol has not been shown to be robust. Proponents stated that their tests did not show any problems with robustness. It was also proposed that a code point could be added to G.hs to provide early identification of bit-swap. An ad hoc group was formed to look into this issue. No agreements were reached at the first ad hoc on bit swap but several “compromises” were tabled. The following proposals were made: • Optional • Mandatory • Optional with Auto-adaptation (new) • Rate Adaption (RA) mandatory • RA optional • RA mandatory with recommendation to use bit swap if a splitter is present • Mandatory, with Auto-disabling (new) • Optional, with a recommendation to use bit swap when splitters are used (new) The auto-adaptation proposal received the most discussion. It was decided to convene another ad hoc group to “flesh out” the proposals. TD-46(WP1/15) (J. Mueller, 3Com) is the report of the second bit-swap ad hoc group. Most of the meeting was spent addressing two of the alternatives, specifically, “the Addition of Rate Adaptive Capability (bit-swap optional)” and “Adding Auto Disabling (bit-swap mandatory).” In line with the group’s charter, no recommendation was made. It does however, recommend the adding of a specific time interval (within 400 ms) for the response to the bit-swap request message to Section 11.2.7 of G.dmt. An informal paper developed during the meeting (WD-bit-unn, F. Van der Putten, Alcatel, Belgium, with France and Italy) offered a compromise which essentially proposes that bit-swap be made optional. It proposes that bit- swap text (lifted from G.dmt) be added to G.lite. It further proposes that the transmitter be allowed to respond with either an ACK (acknowledge) or an UTC (Unable to Comply) and that it recommend (but not mandate) that an ACK be sent if the environment includes an in-line filter or a POTS splitter. It also proposes text, which includes the 400 ms value proposed above. After conferring in delegations outside of the meeting, the group accepted this proposal. Transfer Delay D.339 (A. Johansson, Ericsson, Sweden) proposes the specification of a single transfer delay with a value of 10 ms. It was clarified that this was proposed as a test value. Sweden later accepted the compromise reached below as also satisfying their requirements. D.317 (S. Abbas, Centillium Technology, USA, representing Multiple US Companies) proposes a general formula for guidance in computing the max payload transfer delay. It also provides a value of 14 ms that should be met un- der a given set of circumstances. D.391 (R. Venkatraman, Silicon Automation Systems, India) proposes that the delay not be specified in the Recommendation. D.397 (G. Reina, Orckit Communications, Israel) agrees with D.391 based on the premise that it is not practical to measure. There was considerable discussion following these papers. It was finally decided to accept the proposal in D.317 with the first number in the formula changed from “6.25” to “4.00” and the required value changed to “10 + (S x D)/4 ms” from “14 ms when (S x D) <= 16”. Power Management/Fast Retrain D.282 (J. Mueller, 3Com) proposes a revised version of 3Com’s Quiescent Mode proposal, for inclusion in the future versions of G.lite and G.dmt. D.380C1 (N. King, Siemens, USA) proposes that this be considered under the present version of G.lite. D.415C1 (F. Van der Putten, Alcatel, Belgium) essentially supports D.282. D.390 (A. Baragi, Silicon Automatic Systems, India) proposes the Quiescent Mode be mandatory in the present version of G.lite. It was decided to consider the possibility of inclusion of Quiescent Mode in the first issue of G.lite.
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D.418 (F. Van der Putten, Alcatel, Belgium) proposes the addition of provision for power management initiation by the ATU-C. This paper was addressed in the power control ad hoc group. D.421 (D. Van Bruyssel, Alcatel, Belgium) proposes solutions for problems identified in the transition from the L3 to the LO state. Proposals are identified with escaping from a failed fast retrain, escaping to fast retrain from full initialization and going to fast retrain from the idle state. The group agreed to the “fast retrain truncate” proposal (which addresses the escape from a failed fast retrain) made in Annex A to D.421. In line with the second proposal, the group agreed that the ATU-C not be allowed to NAK a request for fast retrain issued by the ATU-R. The mechanism of using a code point in G.hs. to initiate this escape was agreed (see D.420, F. Van Der Putten, Alcatel). The exact placement of the code point was put off for further discussion. The decision on the proposals in Annex C (proposed text for fast retrain initiated from idle state) and Annex E (proposed text for state diagrams) of D.421 was deferred pending discussion in an ad hoc session on “fast retrain/power management.” TD-47(WP1/15) (R. Hamdi, Compaq, USA) is the report of the report of the Fast Retrain/ Power Management Ad hoc. It includes proposed revised text for Annexes A through D: A - Proposed Text for Fast Retrain Truncate B - Proposed Text for Transition from L3 to L0 C - Proposed Text for Fast Retrain Initiated From Idle State D - Proposed Text for Escape to Fast Retrain D.423 (D. Van Bruyssel, Alcatel, Belgium) proposes that the PSD levels for C-PILOT-FR1 and R_RECOV be maintained at the level of preceding signals rather than allowing them to be dropped to a vendor discretionary level as presently specified. The group agreed to the proposal in Annex A (proposed changes to fast retrain procedures) of D.423. D.466 (K. Cone, Lucent) examines the impact on ATM of the L0 to L1 transition and concludes that this will not cause a problem. It also concludes that the L1 state must support a minimum ATM data rate of 32 kbit/s in order to support ATM signaling protocols. No text changes are proposed. D.368 (J. Carlo, TI) proposes changes in values of the R-LINE PROBE and C-REVERB-FR6 signals used in fast retrain. The meeting agreed to the new value of 512 ms for R-LINE PROBE. It also agreed to an exact value of 400 ms for C-REVERB-FR6. D.366 (F. Van der Putten, Alcatel, Belgium) analyzes the timing recovery procedures in G.dmt and G.lite and concludes that they are adequate to work with G.hs. TD-43(WP1/15) (T. Cole, AMD) is the report of the ad hoc group on Power Management. This report proposes replacement text. It recommends the removal of the L2 state (and reserving it for future use by the ITU-T), and reserving the Power Management states 128 through 255 for vendor-specific use. The group accepted the report and the proposals. European Performance Requirements WD-12(WP1/15) is a report of the ad hoc group on European performance Requirements for G.dmt and G.lite. It was clarified that the Europeans would require in-line filters in any installations. The group accepted the technical proposals. These include having separate regional performance requirements (Annexes) in both G.lite and G.dmt, revising the European G.lite and G.dmt test cases (to include longer loops and increased data rates with lower noise) and to rename Kirkby noise to Euro-K noise. Trellis Coding, 1-bit Constellations, and Improved Efficiency Framing D.392 (R. Venkatraman, Silicon Automation Systems, India) proposes that the one-bit constellation be mandatory in both G.lite and G.dmt. D.332 (R. Hamdi, Compaq, USA) proposes that Trellis coding, 1-bit constellation, and efficiency framing not be included in G.lite at this time. D.342 (A. Johansson, Ericsson, Sweden) proposes to include a Trellis coding option. Later in the meeting, Sweden offered a compromise which would involve putting information on Trellis coding in an Appendix which would be purely informative. Deutsche Telekom and France expressed support for this compromise. The editor obtained the groups’ agreement to the wording below for the text of the proposed Appendix:
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“In anticipation of future revisions of this Recommendation manufacturers are encouraged to implement and investigate implementing the performance of Trellis coding in a splitterless environment as specified in Recommendation 992.1. Implementers wishing to investigate the use of Trellis coding should negotiate its use via the non-standard facilities capabilities of G.hs.” D.400 (G. Reina, Orckit, Israel) proposes to include a Trellis coding option. D.316 (S. Abbas, Centillium, USA, representing Multiple US Companies) proposes 1-bit constellations for future versions of G.lite. D. 396 (G. Reina, Orckit, Israel) proposes including a 1-bit constellation option. D.392 (R. Venkatraman, Silicon Automation Systems, India) proposes a mandatory 1-bit constellation. D.318 (S. Abbas, Centillium, USA, representing Multiple US Companies) proposes increased framing efficiency for G.lite-bis. D. 398 (G. Reina, Orckit, Israel) proposes an optional efficient framing mode. The group agreed to study the inclusion of trellis coding, 1-bit constellation and increased efficiency framing in future issues of G.lite. Eventually it was agreed to leave trellis coding (see wording above), 1-bit constellations and increased efficiency framing for further study. Miscellaneous D.388 (A. Verme, Silicon Automation Systems, India) describes what is characterized as a low complexity method for reducing Peak-to-Average (PAR) power. D.389 (A. Verme, Silicon Automation Systems, India) notes that, as it is possible to design PAR power reduction schemes that are totally transparent to the receiver, no provision for PAR management needs to be specified in the Recommendation. D.340 (A. Johansson, Ericsson, Sweden) proposes the inclusion of an echo canceling option in G.lite. There was no discussion as G.lite presently specifies an echo canceling option. D.399 (G. Reina, Orckit Communications, Israel) notes a flaw in the formula used to compute the power constraint and recommends that it either be modified or removed. Resolution and Final G.lite Agreements WD-4(WP1/15) (C. Hansen) is an interim version of the G.lite Recommendation. During the meeting the editor reviewed the changes to this document point-by-point, obtaining agreement to the changed items. The accuracy of the power formula in Annex A and Annex B was again brought up. Annex B - An issue relating to the use of a100 ohm impedance for the 0-4 kHz measurement was raised. In the tables in Annex B it was agreed to replace the term “FDM G.lite” with “Annex A G.lite” TD-44(WP1/15) (C. Hansen, Intel, USA) proposes revised text for sections 11.2 and 11.3, (Handshake ATU-C and Handshake ATU-R, respectively) which incorporates the agreements made at this meeting. It was accepted. Eventually all open issues were resolved; TD-45(PLEN)© (C. Hansen, Intel, USA) is the final text of G.992.2 (G.lite) which was Determined by SG15. G.DMT S. Palm (Matsushita) is the editor of G.992.1, G.dmt, ADSL Transceivers. TD-26(WP1/15) (S. Palm, Matsushita, Japan) is the Issues List for G.dmt TD-07(WP1/15) (S. Palm, Matsushita, Japan) is a liaison from SG12 responding to a request for information on ADSL interference into POTS. TD-37(WP1/15) (L. Brown, Motorola, USA) from SG16 provides a pointer to where information on billing tones could be obtained. TD-10(WP1/15) (T. Geary and G. Sullivan, SG16 Q11 and Q15 Rapporteurs) provides characteristics of various multimedia applications which could be provided over xDSL facilities.
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TD-27(WP1/15) (T. Geary, SG16 Q11 Rapporteur) identifies some possible approaches to multimedia applications: • Entire xDSL capacity is devoted to delivery of IP without any special QoS support • Some of the xDSL capacity is devoted to baseband voice and some to IP. • A QoS aware protocol (“probably ATM”) is used to convey voice and IP. TD-28(WP1/15) (G. Sullivan, Q15/16 Rapporteur) provides information on the video coding work in SG16. TD-36(WP1/15) (L. Brown, Motorola, USA) reports on the progress of Rec. V.90. It offers L. Brown as a liaison officer. TD-06(GEN) from SG4 provides a proposal for integrated management of telecom and IP networks; it requests comments. TD-08(GEN) from SG12 Q18 reports on their study on voice quality over IP. TD-09(GEN) (S. Palm, Matsushita, Japan) from SG12 reports on the acoustical properties of “hands free” modems contained in P.30 Group audio terminal, P.340 Transmission characteristics of hands-free telephones, P.341 Transmission characteristics for wideband (150-8000 Hz) digital hands-free telephony terminals, and P.342 Transmission characteristics for telephone-band (300-3400 Hz) digital loud-speaking and hands-free telephony terminals. TD-24(GEN) (L. Brown, Motorola, USA) from SG16 discusses modem testing and requests information from SG15 on the digital network characteristics. Interworking with T1.413 issue 2 D.284 (G. Sebek, France Telecom) proposes that specific statements should be included in G.lite and G.dmt to clarify that interworking with T1.413 issue 2 is possible. It proposes that this interworking should not require changes to the hardware. D.341 (A. Johansson, Ericsson, Sweden) proposes that an Annex be added to G.dmt (or G.hs as verbally amended by the presenter) which would provide a pointer to T1.413. D.419 (F. Van der Putten, Alcatel, Belgium) proposes changes to G.dmt to further align it with T1.413 issue 2. It further proposes that if these changes are accepted into G.dmt, they should also be incorporated into G.lite. The group generally accepted all of the proposals in this contribution. After discussion, it was finally decided that the interworking issue would be discussed under G.hs (see below). European Performance Requirements D.424 (D. Van Bruyssel, Alcatel, Belgium) proposes performance requirements for the European loops to be included in G.dmt. D. Van Bruyssel stated that the information in this document was superseded by WD- 12(WP1/15), a report of the Ad Hoc group on European Performance Requirements for G.dmt and G.lite. A final decision on the status of the proposals in WD-12(WP1/15) was deferred in response to a request from France. N. Billington (BT) reported on the recommendations of the European test case ad hoc. The proposal is to modify Annex G by deleting section 3.1 and to use the tables in WD-12(WP1/15). The group accepted this proposal pending agreement on final text. Transfer Delay D.339 (A. Johansson, Ericsson, Sweden) proposes the specification of a single transfer delay with a value of 10 ms. The proposal was to incorporate this value into the appropriate Annex. It was clarified that this test would only be related to the crosstalk tests (not the impulse noise tests). The final decision was deferred pending the development of text in the editing group. It was later agreed to include the 10 ms limit in Annex F, ATU-x Classification and Performance for Region A (Other than Europe). However, concerns were expressed when it was proposed to add this to Annex G, ATU-x Classification and Performance for Region B (Europe). D.408 (Y. Okamura, NEC, Japan) proposes the continued study of a means to reduce the latency figure for Annex C (Specific Requirements for an ADSL System Operating in the Same Cable as ISDN) with the goal of closing this issue at the January Rapporteurs’ meeting. The group agreed to this work plan. D.448 (W. Matsumoto, Mitsubishi, Japan) proposes the Low Payload Transfer Delay method as one of the latency reduction methods in a revised G.dmt Annex C.
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Miscellaneous D.376 (J. Torres and V. Demjanenko, VoCAL Technologies, USA) proposes that an optional Serial Concatenated Convolutional coder be included in future versions of G.dmt. D.420 (F. Van der Putten, Alcatel, Belgium) proposes code points, and was discussed under G.hs. The group, however, gave its endorsement to the proposals contained in Section 3.2 as they applied to G.dmt. G.dmt Final Text TD-44(PLEN)© (S. Palm, Matsushita, Japan) is the final text for G.992.1 (G.dmt) Asymmetrical Digital Subscriber Line (ADSL) Transceivers. It was Determined at the SG15 plenary. G.REF S. Abbas, Centillium Technologies) is the editor of G.995.1, G.ref, Overview of DSL Recommendations. TD-24(WP/15) (S. Abbas, Centillium Technologies, USA) is the draft Recommendation G.ref as input to this meeting. However, as WD-05(WP1/15) represented an update to this, it was not presented. A detailed review of WD-05(WP1/15) was made. TD-38(WP1/15) (S. Abbas, Centillium Technologies, USA) is the G.ref issues list. TD-47(PLEN)© (S. Abbas, Centillium Technologies, USA) is the final text for G.995.1 (G.ref), Overview of Digital Subscriber Line (DSL) Recommendations. It was Determined at the SG15 plenary. G.HS L. Brown (Motorola) is the editor of G.994.1, G.hs, Handshake Procedures for DSL Transceivers. D.293 (S. Palm, Matsushita, Japan representing multiple Japanese comapnies) proposes adding the tone index 64 to indicate incompatibility with Annex A. D.329 (T. Starr, Ameritech, USA) proposes a mechanism for initiating a connection with legacy equipment (T1.413). D.404 (S. Palm, Matsushita, Japan) proposes refinements to G.hs. The proposals were broken down into “editorial matters,” “completion of open items and text deficiencies,” and “configuring xTU-R G.hs using G.ploam.” The editorial proposals in section 2 were accepted. D.414 (F. Van der Putten, Alcatel, Belgium) proposes changes to G.hs to help clarify the text. The proposal for a modulation formula was accepted; editorial changes will be made to clarify Octet transparency and parsing of data blocks. WD-hs(WP1/15) (L. Brown, Motorola, USA) is the report of the G.hs ad hoc group. Agreements reached: • New text for T1.413 interworking • Flag corruption, the length of Message Type and Revision • The structure of the Vendor ID field • The maximum transmit power • Adding tone index 64 to Table 1 • Adding an appendix for provider code information • The inclusion of sample sessions in an appendix • Moving the Level 2 and lower PARS back to G.hs • Moving the spectral coding information to the standard information field GS-016R2(WP1/15) (L. Brown, Motorola, USA) is the updated Issues List for G.hs. The editor briefly reviewed the changes to this document, obtaining agreement to the changed items. He then got the agreement of the group to close the majority of the open issues. The proposals in D.420, code points for G.hs (F. Van der Putten, Alcatel, Belgium), were addressed. It was agreed to accept the tables proposed in section 3.1. TD-31(WP1/15)© (L. Brown, Motorola, USA) is the draft Recommendation G.hs and the Issues List. There was considerable discussion about the provision of a feature for indicating that the xTU-C is connected but not ready to start a G.hs session. It was decided to put a placeholder here and address this at the January Rapporteurs meeting. It was agreed to assign the fast retrain code point as a level 2 PAR. Conversely, C-TONE was moved up to a level 1 PAR. The group also agreed that there would only be three levels of parsing.
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GS-006(WP1/15) (L. Brown, Motorola, USA) is the final text of G.994.1 (G.hs) proposed for Determination. During the point-by-point review of the text, the French delegation once again raised the issue of the need for a more definitive specification of the support of interworking with T1.413 issue 2. With the caveat that some text would be developed to satisfy the French concern, the group accepted the document for Determination. G.994.1 (G.hs) Handshake Procedures for Digital Subscriber Line (DSL) Transceivers, was Determined as TD-46(PLEN)© at the SG15 plenary. G.TEST M. Tzannes (Aware) is the editor of G.996.1, G.test, Test Procedures for DSL Transceivers. D.314 (T. Cole, AMD, USA, representing Multiple US Companies) proposes a modification to the test procedures in G.test to take into account that in-line filters might be used in the field, by allowing the use of in-line filters in the tests if appropriate. D.443 (K. Kikushima, NTT, Japan) proposes revisions to the section of G.test that relates to testing G.lite in the presence of TCM-ISDN disturbers. The in-home wiring models were accepted. D.444 (K. Kikushima, NTT, Japan) proposes simple models for off-hook, on-hook impedances, which could allow repeatability of testing. D.416 (F. Van der Putten, Alcatel, Belgium) proposes to use appropriate values and formulas from T1.413 issue 2 to further align the work. WD-POTS-QOS(WP1/15) (M. Tzannes, Aware) is the output of the POTS QoS ad hoc. It contains some minor text modifications to clearly specify where an in-line filter would be inserted in the test set if it were appropriate. TD-48(PLEN)© (M. Tzannes, Aware) is the final text of G.test proposed for Determination. Draft Recommendation G.996.1 Test Procedures for Digital Subscriber Line (DSL) Transceivers, was Determined at the SG15 plenary. G.PLOAM A. Johansson, Ericsson) is the editor of G.997.1, G.ploam, Physical Layer Management for DSL Transceivers. WD-01R1© (A. Johansson, Ericsson, Sweden) is the text of draft Recommendation G.ploam including the changes given in TD-22(WP1/15). D.417 (F. Van der Putten, Alcatel, Belgium) proposes clarifying text changes to sections 7, 8, and the Appendix of the Draft Recommendation. The group accepted the proposed changes. TD-49(PLEN)© (A. Johansson, Ericsson, Sweden) is the final text of G.997.1 (G.ploam) Physical Layer Management for Digital Subscriber Line (DSL) Transceivers proposed for Determination. It was Determined at the SG15 plenary. Dick Brandt dB Consulting
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WP1/15 PARTIAL MEETING ROSTER, OCTOBER 12 – 23, 1998, GENEVA, SWITZERLAND
Peter Wery, Nortel, Canada SG15 Chair Gastone Bonaventura, Telecom Italia, Itay SG15 Vice Chair Makoto Yamashita, NTT, Japan SG15 Vice Chair Andrew Nunn, BT, UK WP1/15 Chair Austria Post und Telekom Austria Gunter Reisinger Belgium Frank Van Der Putten Belgium Alcatel Bell Jan De Groote Belgium Alcatel Bell Danny Van Bruyssel Canada Peter Wery Canada Mitel Gordon Reesor Canada Mitel Silvana Rodrigues Canada Newbridge Networks F. Tian Canada Nortel Christian Bourget Canada Teleglobe Canada Surendra Sharma China Chen Yun Zhi China He Yida China Jiang Jing China Mao Qian China Peng Yang China Ren Shun Yao China Wang Jun Hua China Wei Le Ping China Zhang Zhi Yi Denmark Danish Electronics Industry Flemming Gerdstrom Denmark Tele Danmark Rune Hylsberg Jacobsen Finland Eino Jauhiainen Finland Vesa H. Kaiharju Finland Helsinki Telephone Co. Pasi Poikolainen Finland Helsinki Telephone Co. Seppo Tormala Finland Nokia Jouko Tormenen Finland Nokia Leif Wikberg France Gilles Joncour France Alain Lhermitte France Luc Peyrat France EUTELSAT Malcom Jones France France Telecom Georges Sebek France IBM Europe Sedat Oelcer France T.R.T. Yannik Schifres Germany Hans L. Koffler Germany Gunther Zedler Germany Alcatel SEL Seigfried Schmoll Germany Alcatel SEL Karl-Albert Turban Germany Bosch Walter Bourdon Germany Bosch Reinhold Feigel Germany Deutsche Telekom Ralf-Rainer Damm Germany Deutsche Telekom Andreas Templin Germany Siemens Paul Drugh Germany Siemens Franz Fimpel Germany Siemens Neal King Germany Siemens Hans-Joerg Thaler Germany Siemens Peter Wildenauer Germany Wandel und Goltermann Wolfgang Miller Great Britain Andrew Nunn Great Britain BT Nigel Billington Great Britain BT Tim Finegan
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Great Britain BT Ian Mann Great Britain BT Jerry Skorkowski Great Britain Cable & Wireless Philip King Great Britain GPT Ghani Abbas Great Britain Lucent Technologies John Magill Great Britain Racal Datacom Chris Firth Great Britain Tektronix UK Mark Lum Greece OTE Harris Katopodis Hungary MATAV Hungarian Telecomm Laszlo Barna India Surinder Kumar Malhotra India Silicon Automation Systems T. Arvind India Silicon Automation Systems Rajagiopalan Venkatraman Israel Reina Guy Israel Amir Ilevitzky Israel Ken Krechmer Israel Ilan Sharfer Israel National Semiconductor Avraham Gal Israel National Semiconductor Salvatore Napolitano Italy Sergio Cascelli Italy Marconi Massimiliano Amirfeiz Italy Marconi Davide Pagnotta Italy Pirelli Cavi e Sistemi Paolo Boero Italy Telcom Italia G. Bonaventura Japan Seiichi Takagi Japan Toshiro Kato Japan DDI Koichiro Tahara Japan Fujitsu Yutaka Awata Japan Fujitsu Akinori Kamijo Japan Fujitsu Ryoji Okita Japan Fujitsu Haruo Yamashita Japan Hitachi Tohru Kazawa Japan KDD Yoshinori Namihira Japan Matsushita Electric Industrial Stephen Palm Japan Mitsubishi Electric Wataru Matsumoto Japan Mitsubishi Electric Yushi Naito Japan NEC Yoshiyuki Moriguchi Japan NEC Yusaku Okamura Japan NTT Koji Kikushima Japan NTT Yoichi Maeda Japan NTT Kazuhiro Oda Japan NTT Masaharu Ohashi Japan NTT Makoto Yamashita Japan Oki Electric Industry Kazuho Kawagushi Japan Oki Electric Industry Yoshihiro Kondo Japan Oki Electric Industry Akihiro Takahashi Japan Sumitomo Electric Industries Kazuya Matsumoto Japan Toshiba Hiroshi Fukinuki Japan Toshiba Yasumasa Kikunaga Japan Toshiba Takeshi Sugoh Korea Yun Bin-Yeong Korea Korea Telecom Myung-Jun Kim Mexico Lucio Adame Netherlands KPN Stefan Op De Beek Netherlands Lucent Technologies Netherlands Peter Stassar Norway Jarle Kiil Norway Telenor AS Vidar Skovli Russia Yuri Alekseev Singapore Singapore Telecom Herjit Singh
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Slovak Republic Slovak Telecom Jozef Nosik Spain Telefonica de Espana Gonzalo Sanchez Gilo Sweden Anders Hoglund Sweden Jorgen Karlsson Sweden L.M. Ericsson Albin Johansson Switzerland Hassane Makki Switzerland AscomTech Angus Carrick Switzerland AscomTech Kurt F. Gfeller Switzerland Swisscom Yu Wang Switzerland TSB Paolo Rosa Syrian Arab Republic Siba Attasi Syrian Arab Republic Kamal Awad Syrian Arab Republic Roula Massouh Ukraine Tetyana Andrushko Ukraine Mykola Biryukov Ukraine Anatoly Glushkovskyy Ukraine Viktor Katok Ukraine V. Victor Panteleev Ukraine Vartan Saroyan USA Elaine Baskin USA Steven Blackwell USA John Chen USA Marcos Maranhao USA James E. Matthews USA John McDonough USA Soching Tsai USA Benson Wang USA 3-COM Joseph Mueller USA 3-COM Richard Stuart USA Advanced Micro Devices Terry Cole USA Ameritech Services Tom Starr USA Analog Devices Rao Nuthalapati USA AT&T Deborah Brungard USA AT&T D. Sparrell USA Aware Marcos Tzannes USA Bay Networks Aleksandar Purkovic USA Bellcore Zhi-Wei Lin USA Centillium Technology Syed Abbas USA Centillium Technology Guozhu Long USA CIENA Corporation Jerry Shrimpton USA CIRRUS Logic Mandayam Krishnan USA Cisco Systems Amir Hindie USA Cisco Systems John Joyce USA COMPAQ Rabah Hamdi USA Corning Mark Soulliere USA Corning Steven E. Swanson USA ESS Technology Yuanjie Chen USA ESS Techonology Ping Dong USA General DataCom Yri Goldstein USA GlobeSpan Technologies Daniel Battu USA GTE BD&I Gary McAninch USA Intel Chris Hansen USA Intel Barry O'Mahony USA Level One Hanan Herzberg USA Lucent Technologies Subramanian Ambati USA Lucent Technologies Randall Brown USA Lucent Technologies Kevin Cone USA Lucent Technologies John Eaves
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USA Lucent Technologies Song Jiang USA Lucent Technologies Hing-Kam Lam USA Lucent Technologies Rick Townsend USA MCI Telecommunications Daryl C. Tannis USA Motorola Information Systems Richard Brandt USA Motorola Information Systems Les Brown USA Motorola Information Systems Ken Cavanaugh USA Motorola Information Systems Bernard Dugerdil USA Pair Gain George Zimmerman USA Paradyne Corp. R.K. Smith USA PC-TEL Gary Anwyl USA PC-TEL Enrico Cadorin USA Pulsecom Dennis Rauschmayer USA Rockwell International Glen Griffith USA Rockwell International Ragnar Jonsson USA RSA Communications Raymond Chen USA SBC Technology Resources Richard McDonald USA SBC Technology Resources John Roquet USA Texas Instruments James Aslanis USA Texas Instruments James Carlo USA VoCAL Technologies Joan Alberto Torres
Communications Standards Review – Telecommunications regularly covers the following committee meetings:
TIA TR-29 Facsimile TR-30 Modems TR-41 User Premises Equipment ITU-T SG8 Telematic Terminals SG15 WP1 Network Access SG16 Multimedia ETSI ATA Analog Terminal Access DTA Digital Terminal Access MTA Multimedia Terminals TC SP Speech Processing TC STQ Speech Transmission Quality TIPHON Voice Over Internet TM6 Transmission & Multiplexing
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ACRONYM DEFINITIONS AAL ATM Adaptive Layer ACELP Algebraic Code Excited Linear Predictor ACTS Advanced Communications Technology Satellite ADSL Asymmetric Digital Subscriber Line AFE Analog Front End AIS Alarm Indication Signal ANAI Access Network Architecture and Interfaces ANSI American National Standards Institute ANT Access Network Transport (Q1/15) API Application Programming Interface ASN Abstract Symbol Notation ATM Asynchronous Transfer Mode B-ISDN Broadband ISDN BER Bit Error Rate BOF Birds of a Feather CELP Code Excited Linear Prediction CI Call Indicator (V.8) CM Call Menu CNI Calling Number Identification CORBA Common Object Request Broker Architecture CPE Customer Premise Equipment CS-ACELP Conjugate Structure -Algebraic Code Excited Linear Predictive DAVIC Digital Audio-Visual Council DC Direct Current DCE Data Circuit Terminating Equipment DCME Digital Circuit Multiplication Equipment DCT Discrete Cosine Transform DMT Discrete Multi-tone Carrier DSS1 Digital Subscriber Signaling 1 DTE Data Terminal Equipment DTMF Dual Tone Multi Frequency ETSI European Telecommunications Standards Institute EURESCOM European Inst. for Research & Strategic Studies in Telecommunications FEC Forward Error Control FEXT Far End Cross Talk FSAN Full Service Access Networks FTTB Fiber to the Building FTTC Fiber to the Curb FTTCab VDSL to the cabinet FTTH Fiber to the Home FWA Fixed Wireless Access GII Global Information Infrastructure GK GateKeeper GSM Global System for Mobile Communications HSD High Speed Data Channel ICG Intersector Coordination Group IDCT Inverted Discrete Cosign Transform IE Protocol Discriminator Information Element IEC International Electrotechnical Committee IETF Internet Engineering Task Force IFTP Informal FTP area IMT International Mobile Telecommunications (IMT-2000) IP Internet Protocol IPDC IP Device Control IPR Intellectual Property Rights iptel Internet Protocol Telephony (IETF Working Group) ISDN Integrated Services Digital Network
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ISDN-BA ISDN basic access ISOC Internet Society ISUP ISDN User Part JM Joint Menu JRG Joint Rapporteurs Group LATA Local Access Transport Area LD-CELP Low Delay CELP LOI Letter of Intent LSD Low Speed Data channel LT Line Termination MAP Mobile Application Part MCS Multi-point Control Services (T.122) MCU Multi-point Control Unit MIB Management Information Base MLP Multi-Layer Protocol MMUSIC Multiparty Multimedia Session Control (WG) MOU Memorandum of Understanding MPEG Motion Picture Experts Group N-ISDN Narrowband ISDN NT Network Termination NTR Network Timing Reference marker OAM Operations, Administration, and Maintenance OAN Optical Access Network OMG Object Management Group ONU Optical Network Unit OPTIS Overlapped PAM Transmission with Interlocking Spectra PAM Pulse Amplitude Modulation PAR Peak to Average Ratio PCM Pulse Code Modulation PCME Packet Circuit Multiplication Equipment PDH Packet Digital Hierarchy PINT PSTN Interworking (IETF) PMD Physical Media Dependent Layer PON Passive Optical Network POTS Plain Old Telephone Service PSD Power Spectral Density PSQM Perceptual Subjective Quality Measure PSTN Public Switched Telephone Network QoS Quality of Service RBS Robbed-bit signaling RDC Remote Device Control REC RECeive alarm RFC Designation for an Internet Standard RTP Real Time Transport Protocol SAT Satellite SCN Switched Circuit Network SCR Selective Call Rejection SDH Synchronous Digital Hierarchy SDL Specification and Description Language SDSL Symmetrical high bit rate Digital Subscriber Line SG Study Group (ITU, CCITT) SLP Service Location Protocol SMG Special Mobile Group SNMP Simple Network Management Protocol SOHO Small Office Home Office SUD Single Use Device TA Terminal Adapter TBR Technical Basis for Regulation (ETSI standard)
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TC Technical Committee TC Transmission Convergence Layer TCP Transmission Control Protocol TINA Telecommunications Information Networking Architecture TSAG Telecommunication Standardization Advisory Group TSB Telecommunications Standardization Board (ITU) UDP User Datagram Protocol UMTS Universal Mobile Telecommunications System UNI User-Network Interface UPC Usage Parameter Control VAD Voice Activity Detector VDSL Very high speed ADSL WG Working Group xDSL all the different Digital Subscriber Lines XNI Customer Network Interface
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70 Vol. 9.8 Copyright © CSR 1998 November-December 1998 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS
1998 STANDARDS COMMITTEE MEETING SCHEDULES AS OF NOVEMBER 4, 1998 Subject to Change without Notice Committee Date(s) Location Committee Date(s) Location Q1/8, Q3/8, Q4/8 Nov 2 - 6 UK Q11-14/16 Rapp. Nov 17 - 20 Torino, Italy Rapporteur ETSI TM6 (only Nov 24 - 27 Sophia Antipolis, Q15/16 Rapp. Nov 3 - 6 Seoul, Korea VDSL and SDSL) France TR-29 Nov 9 - 13 Arlington, VA T1E1 Nov 0-Dec 4 Texas TR-30 Nov 9 - 13 Clearwater, FL ETSI ATA Dec 7 - 11 South Africa ETSI DTA Nov 16 - 18 Berlin, Germany Q4/16, Q10/16, Dec 7 - 10 San Diego, CA TR-41 Nov 16 - 20 Palm Springs, CA Q23/16 Rapp.
1999 STANDARDS COMMITTEE MEETING SCHEDULES AS OF NOVEMBER 4, 1998 Subject to Change without Notice
Committee Date(s) Location TR-41 May 17 - 21 --- Q1/16 Rapp. January Tokyo ITU-T SG16 May 18 - 28 Santiago, Chile ETSI TIPHON Jan 11 - 15 S. Antipolis, Fr. T1E1 Jun 7 - 11 --- Q4/15 Rapp. Jan 18 - 22 Orlando TR-30 Jun 14 - 17 California Q3/16 Rapp. Jan 19 - 21 California ITU-T SG15 Jun 21-Jul 2 Geneva TR-29 Feb 8 - 10 Newport Bch, CA Q15/16 Rapp. July --- TR-30 Feb 8 - 11 --- ETSI TIPHON July Manchester, UK TR-41 Feb 21 - 26 Sarasota, FL TR-30 Aug 9 - 12 Quebec City, PQ ETSI TM6 Feb 22 - 26 Tel Aviv, Israel TR-41 Aug 23 - 27 --- Q11-15/16 Rapp. Feb 23 - 26 New Jersey, US T1E1 Aug 22 - 23 --- ETSI TIPHON March New Jersey, USA ETSI TM6 Sep 20 - 24 UK T1E1 Mar 8 - 12 --- TR-30 Oct 11 - 14 Baltimore, MD ITU-T SG8 Mar24-Apr 1 Geneva Q15/16 Rapp. November Q4/15 Rapp. Mar29-Apr 2 Melbourne TR-41 Nov 15 - 19 Reno, NV TR-30 Apr 12 - 15 --- TR-30 Nov29-Dec 2 --- ETSI TIPHON May Belgium ETSI TM6 Nov29-Dec 3 Netherlands ETSI TM6 May 3 - 7 Grenoble, France T1E1 Dec 6 - 10 --- Q4/15 Rapp. May 10 - 14 Boston, MA T1E1.4 Interim May 17 - 18 Boston, MA Committee Date(s) Location
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Communications Standards Review –Telecommunications (ISSN 1081-4655) is published 8 - 9 times per year, within days after the latest, related standards meetings. Editor: Elaine J. Baskin, Ph.D. Technical Editor: Ken Krechmer. Copyright © 1998, Communications Standards Review. All rights reserved. Copying of individual articles for distribution within a subscriber organization is permitted. Subscriptions: $695.00 per year worldwide, $795.00 in electronic format. Corporate Intranet subscriptions (site license for multiple copies) are available. Submit articles for consideration to: Communications Standards Review, 757 Greer Road, Palo Alto, CA 94303-3024 U.S.A. Tel: +1-650-856-9018. Fax: +1-650-856-6591. e-mail: [email protected]. WWW: http://www.csrstds.com. 19908
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