CSR Volume 11 #10, November 2000

COMMUNICATIONS STANDARDS REVIEW

Volume 11, Number 10 November, 2000

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. Q15/16, Advanced Video Coding Experts Group, August 22 – 24, 2000, Portland, OR, USA...... 2 Coordination of Video Coding Needs With Other Organizations...... 4 H.263 Proposals...... 5 H.26L Proposals...... 6 Error Resilience Aspects of H.26L...... 8 Intra Coding...... 10 Entropy Coding...... 12 Motion Representation...... 12 Test Model, Software Development, and Encoding...... 14 Workplan for H.263...... 14 Workplan for H.26L...... 14 Roster of Q15/16 Rapporteurs Meeting, August 22 – 25, 2000, Portland, OR...... 17 ITU-T World Telecommunication Standardization Assembly, Sep. 27 – Oct. 6, 2000, Montreal, Canada...... 18 Summary of Resolutions and Recommendations Approved by WTSA 2000...... 20 ETSI Access and Terminals (AT) Committee Meeting, October 9 – 13, 2000, Sophia Antipolis, France...... 22 Analog Working Group...... 23 Digital Working Group...... 27 Features Working Group...... 29 ETSI AT Meeting Roster, October 9 – 13, 2000, Sophia Antipolis, France...... 31 TR-30, Data Transmission Systems and Equipment, October 9 – 13, 2000, Columbia, MD...... 32 TR-30.1, Modems...... 32 TR-30.2, Data Transmission...... 34 TR-30.3, Data Communications Equipment Evaluation and Network Interfaces...... 35 TR-30 Meeting Roster, October 9 – 13, 2000, Columbia, MD...... 40 Q4/15, xDSL Network Access Transceivers, Rapporteurs Meeting, Oct. 23 – 27, 2000, Bangalore (Goa), India..... 41 G.gen...... 41 G.shdsl...... 50 G.vdsl...... 51 G.pnt...... 52 G.lite.bis...... 52 G.dmt.bis...... 52 G.hs.bis...... 53 G.ploam.bis...... 54 G.test.bis...... 54 G.ref.bis...... 54 G.voice...... 54 TR-29, Facsimile Systems and Equipment, November 1 – 2, 2000, Arlington, VA...... 56 TR-29 Meeting Roster, November 1 – 2, 2000, Arlington, VA...... 58 Acronym Definitions...... 59 Year 2000 Standards Committee Meeting Schedules as of November 20, 2000...... 62 Year 2001 Standards Committee Meeting Schedules...... 62 Communications Standards Review Terms of Distribution for Electronic Format...... 63

November 2000 Vol. 11.10 Copyright © CSR 2000 1 COMMUNICATIONS STANDARDS REVIEW REPORT OF Q15/16, ADVANCED VIDEO CODING EXPERTS GROUP, AUGUST 22 – 24, 2000, PORTLAND, OR, USA The eleventh meeting (Meeting “K”) of the ITU-T Advanced Video Coding Experts Group was chaired by G. Sullivan (Microsoft), the Q15/16 Rapporteur. Q15-K-60d1 is the meeting report. Q15-K-00 is the document list. Q15-K-01 is the report of the May Osaka meeting. Q15-K-00 is the list of contributions to this meeting. Q15-K-TD-1 is the meeting plan. Documents for this and other meetings, and other information pertinent to the activities of the Advanced Video Coding Experts Group, can be found on the Q15/16 ftp site hosted by PictureTel corporation and managed by the Rapporteur: ftp://standard.pictel.com/video-site http://standard.pictel.com/ftp/video-site Documents for this meeting are in the 0008_Por subdirectory of the ftp site. The email reflector for Q/15/16 is hosted by PictureTel Corp. To subscribe or unsubscribe to this email reflector, send a plain-text email message to: [email protected] in which the body of the email message is in the following format: subscribe itu-adv-video YOUR-EMAIL-ADDRESS The address for email to be sent to all members of the email reflector list is: [email protected] The current study period ends this year; a new charter and organization of work will be constructed in September, with Advanced Video Coding likely being continued as a Question, although probably no longer as Question 15. Reports were presented for the five ad hoc committees that were established at the previous meeting: Ad Hoc Committee Chair Report Simulation Conditions and Error Resilience Testing S. Wenger Q15-K-04 Test Model Enhancement and Software K. Hibi Q15-K-05 Development H.263++ Development G. Sullivan Q15-K-06 H.26L Development K. Hibi Q15-K-07 H.26L Network Adaptation Layer Definition T. Stockham–mer (aided by J. Pandel and Q15-K-08 G. Bäse)

SIMULATION CONDITIONS AND ERROR RESILIENCE TESTING

Q15-K-04 (S. Wenger, Technical University of Berlin) reports that there has been no activity of this ad hoc since the Osaka meeting. H.263++ TEST MODEL ENHANCEMENT AND SOFTWARE DEVELOPMENT

Q15-K-05 (K. Hibi, Sharp Corporation) is the report of the ad hoc committee on test model enhancement and software development. No interim collaborative work was reported, but some topics of discussion for this (Portland) meeting are proposed in the report, including: • The need to add support for new H.263++ annexes in the H.263 test model • The potential promotion of the H.263 test model to a more official form such as a technical report, implementer’s guide, or appendix to the H.263 Recommendation Q15/16 embraced both of these suggestions, targeting improvement of the test model and then adopting it as Appendix II to H.263 (replacing the current non-normative recommended optional modes appendix) in the spring of 2001 (see also Workplan for H.263, below). H.263++ DEVELOPMENT

Q15-K-06 (G. Sullivan, Microsoft) is the ad hoc report on H.263++ development. A major milestone was reached in July with the submission of the white contribution H.263++ Draft Annexes U (enhanced reference picture

selection), V (data partitioned slices), and W (additional supplemental enhancement information) for Decision in Geneva in November. No significant problems were reported in the submitted text, but a couple of minor corrections might be needed in Geneva. Any changes to be suggested should be submitted as Delayed contributions for consideration in Geneva (see also H.263 proposals, below). Q15-K-42 (T. Einarsson & R. Sjöberg, Visual Technology, Ericsson Research Ericsson Radio Systems) proposes to modify Appendix II with recommended optional enhancements. The plan was discussed at the ad hoc and was modified to create a new normative Annex X (see also H.263 proposals, below). The plan described in the ad hoc report to adopt a test model description as Appendix III was modified by Q15/16 to instead use the drafted test model description as a replacement for Appendix II, and to defer the adoption until Decision of the new Annex X. H.26L DEVELOPMENT

Q15-K-07 (K. Hibi, Sharp Corporation) is the report of the ad hoc committee on H.26L development. It reviews the H.26L current draft status, experiment status, relevant contributions to the meeting, key technical areas, functionality requirements, workplan, and top priorities (see also H.26L proposals, below). H.26L NETWORK ADAPTATION LAYER

Q15-K-08 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, Siemens) is the report of the ad hoc committee on H.26L network adaptation layer (NAL); it reports the status of work on definition of network interfaces for H.26L. This ad hoc group was established at the last meeting to address several aspects in the standardization of H.26L which are not primarily connected to coding efficiency. This includes the generation of appropriate network interface including a data format and control and setup mechanisms. The mandate, the key technical areas, and the functionality areas are identical to the H.26L ad hoc group. However, the work in this group intends to focus on many topics related to system aspects not previously addressed by H.26L standardization. It will be necessary to define whether the NAL will be part of the TML document or whether an additional document will be generated. The following documents submitted to the ad hoc address topics on network adaptation and functional requirements: • Error resilience test conditions: Q15-K-15, Q15-K-16 • Data partitioning: Q15-K-17, Q15-K-18 • Network adaptation: Q15-K-19, Q15-K-20, Q15-K-42, Q15-K-43

AMENDMENT AND CORRIGENDUM TO H.262 | ISO/IEC 13818-2 (MPEG-2 VIDEO)

The progress of work on the new amendment (MPEG-2) for adding content description data to H.262 video bitstreams was described. It was also noted that a new corrigendum had been drafted for H.262 video. The white documents for the amendment and corrigendum were submitted to the ITU in July. Members were encouraged to participate in the work of finalization, which is expected to occur primarily within ISO/IEC JTC1 SC29/WG11. This work appears to be on track for final approval at the November SG16 meeting in Geneva. There were no contributions on these issues to the Portland meeting. H.263 IMPLEMENTERS GUIDE

Q15-K-47 (G. Sullivan, Microsoft) proposes clarifications to the draft H.263 Implementers Guide. It includes prior material reviewed at other meetings, plus an additional item regarding whether macroblock stuffing is allowed just prior to a start code. Q15/16 agreed that this contribution contained valuable information for implementers of H.263. It was suggested that it would be useful to investigate inclusion of two other issues in the implementers guide: • Some remarks about the interaction between Annex J (Deblocking Filter) and IDCT rounding error • Clarification of the use of Annex P (Reference Picture Resampling -- Impl. Factor of 4) with Annex N (Reference Picture Selection - Other RPS methods) Q15/16 asked for a new implementers guide draft to be produced as Q15-K-49, to include some remarks on these issues.

COORDINATION OF VIDEO CODING NEEDS WITH OTHER ORGANIZATIONS

VIDEO REQUIREMENTS FOR FUTURE ITU-T S YSTEMS WORK

Q15-K-14 (Q. Gu, P. Luthi, PictureTel) proposes text for changing the H.242 and H.245 signals for use of the factor-of-four reference picture resampling (RPR) feature of H.263+ Annex P. It lists seven difficulties in the resolution capability exchange as proposed in Q15-J-30 (Q. Gu, PictureTel; Osaka), and proposes solutions for dynamicPictureResizingByFour capability exchange: If any resolution H x V that is explicitly declared by the H.242/H.245 capset or implied by the H.263 standard (called a “native resolution”), is declared with the capability dynamicPictureResizingByFour, this shall mean that up to two new resolutions (called “derived resolutions”) H/2 x V/2 and H/4 x V/4 are also supported, as long as these resolutions are greater than or equal to SQCIF both vertically and horizontally. Such derived resolutions shall inherit all the H.263 options of the parent native resolution, including having support for the same Annexes, MPI (Minimum Picture Interval) and clock frequency. This was discussed with Q11-14/16 in a joint session; there was no opposition to the suggested changes. It was understood that the proponents of this issue would need to act to have it considered at the November SG16 meeting. Q15-K-37 (P. Luthi, PictureTel, Editor) contains proposed text for the Implementers Guide for the H.320 series recommendations (Narrow-band visual telephone systems and terminal equipment), including H.263 mode capability negotiation methods. It includes changes made against the May 1999 revision of H.221, H.230, and H.242. This topic was discussed in a joint Q11/Q15 session; the work done on this topic was appreciated. Further evolution of the implementers guide contents should be closely coordinated with any evolution of the relevant H.263 contents, e.g., Annex X. An additional topic of relevance to Q15/16 work was discussed in a joint session with Q11 - 14: “uneven level protection” / “unequal error protection” for H.323 Annex I (Mobility) (APC-1905 of Q12 - 14), draft text for generic uneven level protection (Annex I, see CSR Vol. 11.8). A method was presented to provide unequal error protection to RTP streams, such that more important data is assumed to be at the start of each packet and that the subsequent data toward the end of each packet is assumed to be less important. Forward error correction (FEC) coding techniques were applied across multiple data packets, with some “parity packets” possibly being shorter than others or shorter than some of the data packets to which they were applied; this resulted in varying degrees of protection against packet loss or data corruption (primarily packet loss). A target application of this design was the carriage of error-robust data partitioned or layer-coded video streams. Discussion considered whether this type of work should be addressed primarily within the IETF or the ITU community; several participants indicated (e.g., TD-12 of Q12 – 14, Portland, OR, see CSR Vol. 11.8) that work in the IETF on such packetization schemes was preferred and that alternative technologies might exist. There was some question as to how warmly such work might be received in the IETF, where the idea of value in corrupted or partially-recovered packets might be a foreign concept. No action was taken on these issues. 3GPP/3GPP2 AND H.263 PROFILES

Two contributions contain proposals for the definition of H.263 profiles and levels for use in 3GPP/3GPP2 and other wireless environments. Q15-K-42 (T. Einarsson, R. Sjöberg, Ericsson) focuses on the needs identified in such applications for the existing H.263v2 features. Q15-K-46 (A. Li, F. Liu, J. Villasenor, UCLA; J. Park, D. Park, Samsung Electronics) emphasizes the usefulness of the new Data Partitioned Slice mode of H.263v3. Q15/16 agreed that 3GPP/3GPP2 and similar wireless environments are an important area of application for H.263. Accordingly, it was agreed to send a collaborative letter to the 3GPP/3GPP2 community regarding these issues (Q15-K-54). See below for more details. ISO/IEC JTC1/SC29/WG11 AND FUTURE VIDEO CODING WORK

Q15/16 elected to convey to ISO/IEC JTC1/SC29/WG11 (MPEG) the status of their current video coding work, particularly on H.26L, the project for development of the next-generation video coding standard. H.26L has achieved notable improvements in video coding technology, in particular including an approximately 2:1 improvement in compression efficiency. The technical design of the new standard will be completed around the end of next year. It was noted that WG11 recently announced a call for technology contributions for future video coding standardization activity. Q15/16 felt that, although WG11 currently has no clear plans about what it will do in response to the requested technology contributions, it is important to seek a way to maximally coordinate any potential future

WG11 video coding work with the ongoing H.26L project. These remarks were drafted into an outgoing liaison statement to WG11 (Q15-K-50, G. Sullivan, Microsoft). IETF AVT AND MMUSIC WORKING GROUPS

Q15-K-56 (G. Sullivan, Microsoft) is a collaborative letter to IETF AVT and MMUSIC working groups on the current status of Q15/16 work on video codec design for IP-network applications as contained in the new draft annex (Annex X) for H.263. The new profiles and levels of decoder capabilities defined in the new draft annex will be defined in a normative manner particularly suitable for use in simplified capability scenarios, specifically including SIP. The new draft annex includes definition of a “Conversational Internet” profile designed specifically to address real-time conversational services on IP networks. It also includes a “High Latency” profile designed for non- conversational services that should also be suitable for many IP network applications. H.263 PROPOSALS

H.263 PROFILES AND LEVELS DEFINITIONS

A number of contributions were presented proposing modifications of and uses for the drafted profiles and levels definitions for H.263. The prior plan for such profiles and levels definitions was to include these descriptions as non-normative text in Appendix II to Recommendation H.263. But, as the discussion progressed, it was agreed that the importance of defining such profiles and levels warranted making these definitions normative. By defining normative definitions, profile and level indications defined in H.263 can be used for simplified capability exchange and to further encourage common interoperability configurations. Thus, Q15/16 agreed to alter its plan and therefore put forward the drafted profile and levels definitions as a new Annex X to be Determined in November at SG16, and then to be Decided a few months later. The primary action taken as a result of these proposals was to create a consensus draft; Q15-K-51r3 (G. Sullivan, Microsoft) is the Annex X draft reflecting Portland meeting result. The intent is to finalize the draft for Determination at the November SG16 meeting with Decision in the Spring of 2001. H.263 USE IN 3GPP, 3GPP2, AND SIMILAR NETWORKS

The following two contributions contain proposals for the definition of H.263 profiles and levels for use in 3GPP/3GPP2 and other wireless environments. Q15-K-42 (T. Einarsson, R. Sjöberg, Ericsson) proposes a new profile with Annexes I (Advanced Intra Coding), J (Deblocking Filter), K (Slice Structured Coding - With all submodes), and T (Modified Quantization). 3GPP already contains a specification for circuit-switched video-telephony (3G-324M), which is based on H.324/M, but has some fundamental differences (H.261 and G.723.1 are replaced by H.263 baseline and AMR as mandatory codecs). It includes recommended options to use MPEG-4 (essentially simple profile) and H.263v2 with some annexes. The recommended H.263 annexes are I, J, K, and T, which are Level I preferred modes, except that Full Frame Freeze is not included and Annex K is added. The new profile proposed covers exactly the 3G-324M specification. Q15-K- 42 includes a listing of the profile Annexes. This contribution also proposes two new levels: QCIF/30Hz/128 kbits/sec and CIF/30Hz/384 kbits/sec. The lowest level corresponds to the 3G-324M spec, which is good, but as the jump in bitrate between the two highest levels is considerable, it may be good to have an intermediate value; also, it is important to have a high frame rate for sign language. The relatively low bitrate of 128 kbits/sec is suggested for QCIF image size. Q15-K-46 (A. Li, F. Liu, J. Villasenor, UCLA; J. Park, D. Park, Samsung) proposes to include Annex V into appropriate profiles of the H.263. Annex V provides error resilience for the H.263 bitstreams. By using data partitioning packet structure and reversible variable length coding (RVLC) of the macroblock header and motion vector partitions, it achieves significant enhancement to the image quality over error prone channels. The capability for H.263 to operate over error prone channels is an important requirement for many applications, especially for application over the 3G wireless networks. Another advantage of Annex V is its capability to generate slice packets that can be tailored to fit nicely into transport layer packets. This is extremely useful for coding H.263 bitstream in packet-switched environments. It avoids segmentation of the video packets at lower level, where loss of one data segment can cause other segments of the same video packets to be discarded even when correctly received.

Q15-K-54 (G. Sullivan, Microsoft) is a collaborative letter to 3GPP TSG-S4 and -S2, and 3GPP2 TSG-C informing them of the Q15/16 work on video codec support for wireless multimedia terminals. The draft new Annex X includes two normative profiles that are specifically targeted for wireless multimedia terminals. The first of these two is based on the design identified in 3GPP 3G-324M TS 26.911 for use of H.263. It contains only features from the original (November 1995) and second (H.263+, January 1998) versions of H.263. The second adds to this package two features of the new, third (H.263++, November 2000) version of H.263 that is expected to be Decided at the November SG16 meeting. This letter asks the 3GPP/3GPP2 community to provide any feedback necessary to determine whether the drafted design is fully adequate. SPARE REFERENCE PICTURES FOR IP NETWORK USE

Q15-K-39 (M. Hannuksela, Nokia Mobile Phones) proposes that support for spare reference pictures be added to the description of H.263 Draft Annex W within the IP network-related profile(s) of the new draft H.263 Annex X. H.263 profile recommendations (Q15-J-12, B. Haskell, AT&T Bell Labs) include a preferred mode set targeted for IP networks (Profile 4). As real-time video communication systems in IP networks typically utilize unreliable transport protocols, such as RTP and UDP, this profile aims at enhanced error resilience. Thus, the profile includes reference picture selection modes ( Reference Picture Selection, Annex N and Enhanced Reference Picture Selection, Annex U). Preliminary results in Q15-J-55 (M. Hannuksela, Nokia Mobile Phones) demonstrate the usefulness of spare reference pictures in error-prone environments; this contribution presents more thorough simulations. Experiment results were provided to support the assertion that this feature can enhance video quality. Q15/16 agreed that these indications are useful and can help provide error resilience to the operation of a video decoder. But they have no normative required response in a decoder, and are enabled in the syntax using backward-compatible supplemental enhancement information; it was therefore agreed that there is no clear need to explicitly require support for these indications in Annex X profiles at this time. H.263 TEST MODEL APPENDIX

Q15-K-40 (M. Hannuksela, Nokia Mobile Phones) proposes an addition to the H.263 Test Model (Q15-G-16r3) to describe how to use picture numbering for error resilience enhancement in the use of B pictures (Annex O). Q15/16 agreed that capturing these remarks in the test model could be valuable, and requested that the test model editor produce a new draft of the test model. A break-out session convened to perform this work and to address any areas of missing information in the draft. The new draft will be produced as Q15-K-52, H.263 draft Appendix II, Test model near term number 13 (S. Wenger [Technical University of Berlin], F. Kossentini [University of British Columbia], H.263 Test Model Editors). H.26L PROPOSALS

H.26L DEVELOPMENT POLICY

Q15-K-20 (D. Lindbergh, PictureTel) proposes five policies for the development of H.26L within Q15/16, intended to increase simplicity, testability, interoperability, correctness, acceptance, and actual real-world performance of H.26L: (a) A system of “Application-Level profiles” instead of individual algorithm options (variation on MPEG model) (b) A requirement for two independent interoperable non-realtime implementations before approval (IETF model) (c) A non-real-time C-code implementation (WP2 audio codec model) (d) Test vectors should be provided (e) A requirement for resource-consumption and performance metrics to accompany all algorithmic proposals H.26L has the potential to be an extremely important codec for the telecommunications industry and for users worldwide; as a next-generation natural-scene video codec, it may eventually replace existing codecs in most applications. Q15/16 discussed this proposal extensively and considered it to be important; the concept was generally supported. But some concern was expressed about whether the method of work could be followed well, and fully, in practice. Q15-K-19 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, Siemens) contains additional remarks on the process of H.26L development. (See also further discussion of Q15-K-19, below.) At the May Osaka meeting, an ad hoc group was established to specify a network adaptation layer (NAL). Q15-H-07 (see CSR Vol. 10.9) addressed the key technical areas and the functionality requirements for H.26L. Though it is clear that the improvement of coding efficiency is the most important goal, it is necessary to address more functionality aspects in

the future. Referring to Q15-H-07, the following functional requirements (see Workplan for H.26L, below, for additional detail) have been identified to be finally supported by the H.26L standard: (a) High compression efficiency (b) Simplification “back to basic approach” (c) Flexible application to delay constraints appropriate to a variety of services (d) Error resilience (e) Complexity scalability (f) Full specification of decoding (no mismatch) (g) High quality application (h) Network friendliness Whereas the items (a), (b) and (f) have been addressed in great detail by the current test model, many of the other topics have not been considered at all. To resolve this problem, Q15-K-19 proposes to separate the two issues, coding efficiency and network adaptation, in two different ad hoc groups and especially address the topics (c), (d) and (h) in the network adaptation layer ad hoc group (NALAG). Ongoing interaction between both groups is necessary to identify common work items. Q15-K-19 identifies two key issues to be addressed by the NALAG: • Specify a generic interface for H.26L to underlying networks • Specify coding options for H.26L and the negotiation of these options Q15/16 discussed a number of potential refinements to the ideas presented. The end result of these discussions is embodied in Q15-K-55, Proposed rules for accepting new proposals to TMLx and H.26L (S. Wenger, Technical University of Berlin; D. Lindbergh, PictureTel). The purpose of this document is to define the rules Q15/16 agrees to work with for the future standardization process of H.26L. The rules help to ensure minimal interoperability problems and simple capability negotiation of systems employing H.26L. To do so, a Profile-Level-Version framework is introduced, that, in spirit, corresponds to the one discussed currently for Annex X (although hopefully doing a better job by preventing divergence at the outset). Q15/16 shall not begin the ITU-T approval process for Recommendation H.26L or its Annex, until the complete C-code for that version has been shown to work and test vectors have been generated and tested on the C-code model. The Q15/16 experts will review this contribution by the first experts meeting of 2001. At that time, the plans, as then discussed and potentially revised, will be considered adopted as strong rules to govern future Q15/16 work. S. Wenger will serve as editor of this guidelines document, and as coordinator of the H.26L software development work. NETWORK ADAPTATION LAYER (NAL) DEFINITION

Several contributions (e.g., Q15-K-17, Q15-K-18) on the subject of definition of a network adaptation layer (NAL) for H.26L were considered. Some similar ideas were presented at the May Osaka meeting in the following contributions: • Q15-J-18, Slices for H.26L (R. Sjøberg, Ericsson) • Q15-J-23, Data partitioning for packet-oriented H.26L transmission - A network-friendly interface (G. Bäse, J. Pandel, S. Purreiter, Siemens; T. Stockhammer, Munich University of Technology) • Q15-J-53, H.26L Error resilience: first results (S. Wenger, Technical University of Berlin/TELES AG) Q15/16 encouraged interested parties to collaborate on how this can be reflected in the test model document and software. The result will be embodied in the test model document (TML-5) as Q15-K-59 (G. Bjøntegaard, Telenor Broadband Services, Editor). The group-maintained software will contain the following features: • Increased flexibility in picture size • Slice support • A packetization oriented toward IP network use • A packetization oriented toward Mobile use NAL CONCEPT AND HEADER DESIGN

Q15-K-19 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, Siemens) discusses the issue of definition of a network adaptation layer for H.26L. It proposes an H.26L layer model with appropriate layer definitions within the design to allow customization of H.26L video to a particular network operating environment while maintaining a consistent coding representation structure. The concept consists of separating the specification design into a video coding layer (VCL) and a distinct network adaptation layer. While a single VCL definition would

presumably exist, each transmission network or storage format could contain a distinct network adaptation layer definition. The VCL would support the building blocks necessary for a number of networks, such as interruption of the spatial and temporal prediction processes to support random access and error-resilient resynchronization, while the NAL would determine how these features are best exposed in a given network, e.g., whether packets preceded by headers are defined as in IP networks, or whether bitstreams containing start codes are defined as has been customary in circuit-switched networks. Q15-K-19 proposes a particular header format for the interface between the VCL and the NAL. STUFFING AND START-CODE EMULATION

Q15-K-36 (K Liang, K. Zhang, C. Huang, Sorenson Technologies) discusses stuffing bits and start-code emulation for H.26L. Stuffing bits are bits included in the output of a codec to take up space for alignment to word-size or packet-size boundaries, or for keeping a transmission channel full when the encoder is not generating sufficient data. In H.26L draft 4, there are no stuffing bits after each frame and the proposed slice structure also does not include the stuffing bits. This makes it difficult to match the packet partition to the packet size. This contribution discusses how stuffing bits can be added to the current H.26L syntax, and what impact this might have on the possibility of start-code emulation. The Q15/16 experts found this information valuable, but were unsure whether it should be immediately adopted into the H.26L design. It was felt that more work is needed on the entire NAL definition issue, and it was unclear how this contribution might fit within that framework yet to be defined. Q15/16 decided to take the contribution as valuable information that may prove useful at a later stage of the NAL definition. IP PACKETIZATION

Q15-K-43 (R. Sjöberg, Ericsson) proposes a simple packetization format based on RFC 2429 (the preferred RTP payload packetization format for H.263) for H.26L. Q15/16 asked the proponent to coordinate and harmonize this work with the other work on H.26L. It was also suggested that greater flexibility regarding picture size support should be embodied in the draft. ERROR RESILIENCE ASPECTS OF H.26L

FINE GRANULARITY SCALABILITY

The following contributions were provided on the subject of fine granularity scalability (FGS). • Q15-K-09 (K. Illgner, G. Baese, Siemens) reports results for the core experiment on fine-granular scalability as defined in Q15-J-70, H.26L Core Experiment Description on Granular Quality Scalability. The fine-granular scalable coding concept performed very well, especially for channels with varying capacity. • Q15-K-10 (D. Marpe, G. Blättermann, G. Heising, Heinrich-Hertz-Institute) presents the results of the core experiment on granular quality scalability according to the conditions given in Q15-J-70. It demonstrates the benefit of having the functionality of granular quality scalability (QS) in a multicast scenario with a time-varying channel. In terms of coding efficiency, the QS-coder provides on the average a better performance than the simulcast technique assuming a multicast scenario with different fixed bitrates. • Q15-K-11 (D. Marpe, Heinrich-Hertz-Institute) contains simulation software for quality scalable codec with fine granularity scalability. • Q15-K-12 (D. Marpe, G. Blättermann, G. Heising, Heinrich-Hertz-Institute) proposes a technical description of a quality scalable coder for H.26L. • Q15-K-26 (C. Mayer, M. Wien, Institut für Elektrische Nachrichtentechnik) presents results of the H.26L core experiment on fine granularity scalability. The proposed FGS scheme shows good performance in comparison to the simulcast scenarios. Especially in the test with time-varying channel bandwidth, the advantage of FGS to smoothly adapt to the available bandwidth can be observed. FGS is a relatively new design feature for video coding; this feature is embodied in some form in a draft of ISO/IEC 14496-2 (MPEG-4). At the May Osaka meeting, Q15/16 discussed a contribution on the same subject (Q15-J-24, A quality scalable mode for H.26L [G. Blättermann, G. Heising, D. Marpe, Heinrich-Hertz-Institute]); an experiment was designed for testing this feature (Q15-J-70). The concept encompasses the construction of a video bitstream with two distinct layers: a conventional base layer and an enhancement layer. In the enhancement layer, the more important information for each picture is sent first, so if the initial portion of the enhancement layer data for a picture is received but some subsequent remaining data for that picture is lost, the received portion of the enhancement layer information is still useful for generating an enhanced representation of the picture. To prevent

artifacts in the enhancement layer due to a lack of knowledge of the value decoded for prior pictures, temporal prediction is not allowed in the enhancement layer. A number of particular design aspects of such a system were explored in these contributions, and experiment results were provided to show the effectiveness of the proposed design. But Q15/16 had difficulty identifying in which key application scenarios the FGS feature will benefit the H.26L design. The FGS design presumes a differentiated quality of service, in which the base layer is highly protected for reception while the enhancement layer is less protected. It also seems to require a multi-level form of this service, in which the first bits of the enhancement layer of each picture are protected more than the subsequent bits. It also assumes that this multi-level differentiated QoS has fine granularity and perhaps time-varying characteristics; otherwise some other form of scalability such as the spatial scalability proposed in Q15-J-40 (M. Wien, M. Beermann, RWTH Aachen U) could be used. Q15/16 questioned whether such a scenario should be considered a sufficiently important application area of H.26L to warrant devoting effort at this stage to adopt special features into the codec to address this scenario. Also, without a good understanding of the likely application scenario, the proper performance metrics to use in optimization of a design remain unclear. Q15/16 therefore decided to not adopt such design features into H.26L until a justification and application scenario could be provided to clearly show the need for such a capability. In an effort to begin collecting information about possible network designs that might incorporate this feature, it was decided to include a question in the liaison statement to the 3GPP/3GPP2 community (Q15-K-54) to help determine whether 3G networks could be expected to provide such services in the near future. DATA PARTITIONING

Q15-K-17 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, S. Purreiter, Siemens) contains data partitioning test software. Q15-K-18 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, S. Purreiter, Siemens) presents results of transmission of H.26L via error prone channels. It distinguishes three different packetization modes, one conventional and two data partitioning modes. Additionally, it introduces prioritized transmission by applying unequal error protection to different partitions. It presents objective and subjective results and shows the benefits of conventional data partitioning and progressive data partitioning. It proposes that data partitioning be introduced in H.26L. Q15-K-16 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, S. Purreiter, Siemens) proposes extended test conditions for video performance evaluation in H.324/M supporting error protection and prioritization. (The Reed-Solomon error protection capability of the adaptation layer of H.223 Annex D is emulated.) By mapping different data packets on different logical channels with different amount of redundancy for error protection, prioritization of certain data is possible such that the probability of a packet loss is reduced; equal and unequal error protection is supported in the test conditions. With these extended test conditions, the benefits of error protection and prioritization are possible without including any forward error correction mechanism in H.26L. Q15-K-16 presents the software used and defines the extended test conditions; it adopts most of the test conditions previously defined in Q15-I-60 (Common conditions for video performance evaluation in H.234/M error-prone systems, S. Wenger, TU Berlin/TELES AG). Q15-K-15 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, S. Purreiter, Siemens) contains PseudoMux H.223/Annex B (Multiplexing Protocol for Low Bitrate Multimedia Communication Level 2) and Annex D (Optional Multiplexing Protocol for Low Bitrate Multimedia Communication over Highly Error-prone Channel) Software. See also Test Model, Software Development, And Encoding, below. The proposed design includes: • A data partitioning design separating mode information, motion vector data, and DC and AC transform coefficients • A “progressive” packetization format with a progressive-refinement ordering of transform coefficients • Unequal level protection applied with varying degrees of error protection for different parts of the video packet • A method of providing prioritization of data at a network interface The submitted software included enhancements to prior “pseudo-mux” software for mobile network simulation (e.g., H.223 Annex D). Greater error protection was shown in some experiments to produce higher video quality, and uneven protection was shown to also provide a performance benefit when using the progressive packetization format. Some concern was expressed over the practicality of assuming support of uneven level protection in networks. As

November 2000 Vol. 11.10 Copyright © CSR 2000 9 COMMUNICATIONS STANDARDS REVIEW with the proposals on FSG, requesting information about future network designs in Q15-K-54 seemed like a good starting point for evaluation. Q15/16 therefore adopted only the simpler packetization format for inclusion in the test model, and deferred investigation of the more advanced hypothetical scenarios pending further information and understanding. INTRA CODING See also Entropy coding enhancement work below relating to intra coding. NOKIA MOBILE VIDEO CODER (MVC) DESIGN

Q15-K-32 (M. Karczewicz, B. Dobrin, J. Lainema, Nokia) presents the results of the core experiment on convergence and improvement on the intra coding design in the Nokia mobile video coder (MVC) proposal. An intra coding performance improvement of typically 0.5 to 1.5 dB gain relative to TML-4 was reported by use of the MVC intra method. Removal of the 4x4 (8 basis function) and 8x8 (16 basis function) Karhunen-Loève Transform (KLT) feature from the MVC design was shown to result in little loss in performance for most sequences (up to 0.5 dB at low rates, but generally less), except for the “Foreman” sequence, which showed approximately a 1 dB loss. Other areas of key difference between the MVC and TML designs include the pixel prediction and entropy coding methods. Q15-K-30 (G. Bjøntegaard, Telenor Satellite Services) reports that the TML design could have a performance improvement for intra of approximately 0.5 dB at high bit rates by deviating from the universal variable-length code (UVLC) entropy coding design. Other experiments with use of the KLT in the TML context by others were noted to result in only about half the reported gain as reported in the MVC case. Q15/16 took no action in response to these contributions. Further investigation of performance differences between the MVC and TML designs was encouraged, toward ensuring that the TML design has a degree of performance consistent with the needs of H.26L (which include “difficult to significantly beat in overall design in a timely fashion”). See also Q15-K-13 below for another indication of significant potential intra coding performance improvement. BLOCKING ARTIFACTS IN SMOOTH AREAS

Q15-K-35 (M. Karczewicz, B. Dobrin, J. Lainema, Nokia) shows that undesirable blocking artifacts can be exhibited when large step sizes are used for intra coding with H.26L. These artifacts were reportedly caused by the 4x4 combined coding of intra DC values in the TML design. Since this combined coding method does improve compression performance, it was desirable to find a way to address the problem of these artifacts without dropping compression efficiency. The proposed method for achieving this goal was to adjust the filtering process for the reconstructed picture, by using a longer (5-tap) and locally-recursive filter rather than the filter previously in the TML design. As this proposal solves a problem that was effectively shown to exist in the current design, it was adopted for inclusion in the test model. WAVELET-BASED INTRA CODING

Q15-K-13 (M. Karczewicz, B. Dobrin, J. Lainema, Nokia) describes a wavelet-based method of intra picture coding. It updates some results reported previously (Q15-I-12) and compares the wavelet method with that of the TML. When chroma PSNR performance was matched, a reported gain of 0.2-0.5 dB was reported at low bit rates, and more than 1 dB of gain was found at high rates. The gain was dramatic at high rates, with the “Mobile and Calendar” and “Tempete” pictures having maximum gains of about 3 dB or more. The wavelet method seemed to have better performance on larger picture resolutions (such as CIF as opposed to QCIF). Some smaller gains were also exhibited relative to JPEG-2000 VM 7.2 software on some large images. Resolution/bit-rate scalability was also a noted feature of the wavelet coding design. Hypothetically, JPEG-2000 or this method could be adopted as a method of coding only intra pictures. A question was raised as to whether an interaction of artifacts (such as “I-Frame Beating”) might occur if the wavelet design was used for intra coding with a block-based scheme used for inter coding. The transform and entropy coding designs of the different methods are very different from each other. Q15/16 must decide how much intra picture coding performance matters to the video codec design; the gain shown was significant in some cases. Q15/16 took no action in response to this contribution.

INTRA PREDICTION FOR CHROMINANCE DATA

Q15-K-28 (G. Bjøntegaard, Telenor Satellite Services) investigates performing directional prediction of chrominance data. For a modest increase in chrominance coding complexity, some performance improvement (approximately 3%) was shown in some experiments. Although Q15/16 had a favorable attitude toward the content of this proposal, it decided not to adopt it at this time in favor of stability in the TML design and in view of the modest performance improvement indicated. BLOCK ORDER FOR INTRA PREDICTION

Q15-K-41 (P. Fröjdh, R. Sjöberg, Ericsson) advocates changing the order of the coding of 4x4 blocks in a macroblock to provide more data for use in spatial prediction of the content. The proponents noted that the same concept could hypothetically be applied to motion vector prediction as well. While intriguing in concept, little gain was shown in the experiment results, with the best performance being about 0.25 dB gain on “Foreman.” Because of the modest gain shown as presented, Q15/16 did not take action in response to this proposal. INTEGER ADAPTIVE BLOCK TRANSFORMS

Q15-K-24 (M. Wien, C. Mayer, J.R. Ohm, Institut für Elektrische Nachrichtentechnik) proposes integer approximations of the DCT matrix of size 8x8 and 16x16 for application with adaptive block transforms (ABT). The transforms both have a norm that is a multiple of 17 and can be operated in 32bit arithmetic. The quantization and coding procedure are designed the same way as in the TML. The quantization procedure uses a set of five quantization tables that reflect the varying norms of the transform blocks. For encoding of the quantized coefficients, scan blocks of 16 coefficients are used. This preliminary approach allows for application of the TML VLC as well as for a simple R-D optimization on the encoder side, similar to the optimization used in the TML. This contribution also describes a technique for removing single non-zero coefficients. The deblocking filter was turned off in these experiments, and rate-distortion optimized quantization was not performed for the modified proposal. The results were compared with the TML but with the TML’s deblocking filter turned off (with the TML’s R-D optimized quantization active). This paper builds on Q15-J-41 which presented the basic idea of ABT, to connect the block sizes of the applied transforms to the size of the blocks used for motion compensation. Since these block sizes are transmitted for motion compensation, no additional side information needs to be transmitted to the decoder. Q15-K-25 (M. Wien, Institut für Elektrische Nachrichtentechnik; T. Halbach, NTNU) gives the simulation results for the proposed ABT. The experiment results were not particularly encouraging. Ideas raised that could potentially help included: changing the coefficient scan order, using a different VLC, performing R-D optimized quantization, and special treatment of chroma. The coding gain for the 16x16 transform may not have been ideal. Some Q15/16 participants were intrigued by the ideas in the contribution, and felt that perhaps further work might result in better performance. A reminder was tendered to keep in mind that visual rather than PSNR performance maximization is the primary goal. Q15-K-57 (M. Wien, Institut für Elektrische Nachrichtentechnik) proposes a core experiment for ABT to find an entropy coding method that matches the statistics of the ABT coefficients. AC CHROMA COEFFICIENT QUANTIZATION

Q15-K-29 (G. Bjøntegaard, Telenor Satellite Services), with accompanying software (Q15-K-31) and performance results (Q15-K-28), investigates the quantization of chrominance data. At the moment, H.26L has a step size adjustment for chrominance data that is patterned from H.263 Annex T (Modified Quantization), which sometimes results in a significant percentage of the bit rate being devoted to chroma. An approach investigated in Q15-K-29 was to use a smaller step size for the DC component of chroma blocks, but allow a larger step size for luminance, to improve overall color. This approach is reminiscent of a feature in ISO/IEC 14496-2 (MPEG-4). The experiment results showed a significant drop in chroma PSNR quality, accompanied by a minor increase in luma quality, e.g., 0.3 dB improvement in luma for 1.5 dB degradation in chroma for “Mobile and Calendar,” or 0.2 dB typical improvement in luma for other sequences for 0.6 dB degradation in chroma. The “Flower Garden” sequence was suggested as a good test case. The theoretical PSNR maximization argument seemed to favor keeping the step size similar for all coefficient frequencies, but some perceptual phenomenon might favor something else. It was suggested that perhaps lower bit rates should be tested to show the artifacts better. Ultimately, Q15/16 took no action on this due to the lack of a demonstration of clear benefit.

ENTROPY CODING

INTRA ENTROPY CODING

Q15-K-30 (G. Bjøntegaard, Telenor Satellite Services) presents a method of adapting the variable-length coding as coding progresses for intra data, along with experiment results (Q15-K-28). A gain of 0.25 to 0.5 dB was shown at high bit rates, i.e., at low quantization parameter values, with use of this technique to switch between the prior UVLC table and a new “VLC2” table. However, the results were described as preliminary and for information only. ENTROPY CODING

Q15-K-45 (L. Kerofsky, Sharp Labs of America) presents an analysis of the entropy coding performance of the H.26L UVLC code which appears to show that significant performance improvement can be obtained for low quantization parameter values. The UVLC code was compared with the VLC2 code presented in Q15-K-30. The design of these codes was compared to that of Golomb codes, which are optimal for geometric pdfs (probability distribution function). A “tree grafting” idea was shown as a method for adjusting the code structure to account for an “inflection point” in the pdf behavior. The UVLC code was asserted to be good for QP>17, and the grafted new code was asserted to demonstrate improvement for QP<13. Using an entropy code as modified, a 5-18% reduction in the bit rate for the transform coefficient part of the bitstream was achieved at low QP values. Q15/16 took no immediate action in response to this proposal, even though it considered the analysis of the issues interesting and well-structured. Further work was encouraged. MOTION REPRESENTATION

AFFINE MOTION

Q15-K-33 (J. Lainema, M. Karczewicz, Nokia) reports the results of integration of affine motion representation into the TML design, based on a core experiment design planned in Osaka (Q15-J-69). The affine motion compensation algorithm was accommodated in the TML software as described in Q15-J-43, MVC motion compensation with TML-2 (J. Lainema, M. Karczewicz, Nokia Research Center). One bit was used to indicate whether affine motion would be used for each 16x16 or 8x8 motion block. Residual differences were coded with an 8x8 DCT (Q15-J-19). Rate-distortion optimized quantization was not used. Performance results reportedly ranged from no improvement to 0.5 dB improvement. The most gain was seen at low bit rates. It is hypothetically possible that coupling affine motion with other features such as 4x4 residual difference coding could help the design. However, these results seem to indicate that simply adding a switch to support affine motion does not appear to justify the added complexity of this feature. Q15/16 took no direct action in response to this; further investigation was encouraged. 1/8-S AMPLE MOTION

Q15-K-21 (T. Wedi, University of Hannover) reports an investigation of 1/8-sample motion vector resolution in which various motion vector resolutions were tested with various filtering methods. It concludes that at high bit rates with high resolution (CIF or higher) some benefit can be shown for increasing the motion vector resolution beyond today’s 1/4-sample TML design to support 1/8-sample motion. The reported gain on “Flower Garden” was up to 0.8 dB and on “Mobile and Calendar” was up to 1.0 dB. A number of sequences showed little or no gain. The sequences which showed the most benefit seemed to be those with steady motion, such as camera motion. The result on video of QCIF resolution was usually a loss in performance. It thus proposes to use 1/4-sample resolution for QCIF or lower resolution and 1/8-sample resolution for higher resolution pictures. The proposed extension of motion vector accuracy to 1/8-sample would not add much complexity to decoding, but would appear to add a significant amount of complexity to the encoding search process. The perceptual characteristics of the video were also unknown. Some concern was expressed that sharp motion compensation filters could aggravate the presence of visible noise in the video (due to allowing high-frequency information into a prediction loop). Although this proposal offers the potential of improved performance for some scenarios, Q15/16 did not feel that it offers sufficient evidence to show that this feature warrants the added complexity; no action was taken.

MOTION VECTOR POSITIONAL FILTERING

Q15-K-27 (G. Bjøntegaard, Telenor Satellite Services) investigates the filtering characteristics of the “special position” having different filtering characteristics in the motion compensation process. It concludes that even with the in-loop deblocking filter, the special position made a visible difference in picture appearance. It was suggested to retain the use of this special filtering position in the TML and to study its characteristics in light of the planned simplification of the in-loop filter and any other yet-to-be-adopted changes to the TML design. The special filtering position could eventually be removed if it provides no benefit, but at the moment the performance impact is unclear and the impact on complexity appears to be minimal. MOTION VECTOR PREDICTION

Q15-K-34 (J. Lainema, M. Karczewicz, Nokia) proposes a modification of the motion vector prediction process to account for the segmentation within the macroblock and the mode and reference picture selection information. Some PSNR gain was shown (about 0.2 to 0.5 dB) on a particular sequence “Stefan” with high motion, although other sequences showed no real significant performance difference. Because the modification had no real impact on complexity, made intellectual sense, and did show some benefit, it was adopted into the test model. PREDICTION FROM TEMPORALLY-SUBSEQUENT PICTURES

Q15-K-38 (M. Hannuksela, Nokia) investigates the use of multiple reference picture buffering in high-delay scenarios such as multicast streaming. In some situations, allowing the temporal prediction process for P pictures to run backward in time appears useful for error resilience, reverse playback, and possibly coding efficiency. Q15- K-38 proposes that P pictures be allowed to use temporally-subsequent pictures as references. Q15/16 judged this proposal to be very much in keeping with the intent of the multi-picture buffering concept. If the display process is viewed as conceptually decoupled from the decoding process, it is easy to enable not only P pictures that have temporally subsequent reference pictures, but also P pictures that have a mixture of temporally prior and subsequent references, and B pictures that have two temporally prior references used in bi-directional averaging prediction, or have a mixture of temporally subsequent and prior reference pictures, or that reference two blocks of the same reference picture to average in forming a prediction. The only remaining distinction then between a P picture and a B picture is that each motion block of a P picture is predicted by, at most, one reference picture region, whereas some motion blocks of B pictures are predicted by averaging the predictions from two reference locations. B pictures then naturally become “multi-hypothesis motion” pictures in the Flierl-Wiegand sense. This decoupling of the display and decoding processes was therefore adopted as Q15/16’s TML design in principle. Each picture to be decoded simply has a pool of available, previously decoded pictures to use as references in the decoding process, and pictures are fed sequentially to the display process from the multi-picture buffer as an activity entirely separate from this decoding process, except that the picture must be in the buffer in order to be sent to the display process. DIRECT PREDICTION IN B PICTURES

Q15-K-44 (K. Lillevold, RealNetworks) proposes an alteration of the direct motion prediction mode in B pictures to accommodate scenarios such as scene-to-scene and scene-to-black fade transitions. Rather than weighting just the values of the motion vectors in the prediction process, it advocates also weighting the averaging combination of the two prediction blocks. It provides some evidence, in the form of experiment results, to show that this will help fade transitions without harming conventional coding operation. It was noted that something resembling this is present in some draft stage of a prior standard (ISO/IEC 11172-2 [MPEG-1]). Q15/16 was favorably disposed to this proposal. The weighting of motion vectors is based on temporal distance in prior standards such as H.263. However, with the decoupling of decoding and display that is found in the H.26L design (see Direct Prediction in B Pictures, Q15-K- 44), it seems no longer prudent to make assumptions about temporal relationships for the references used by B pictures. Therefore, the proposal was modified to specify a weight factor by directly sending it as a multiple of 1/16, using 4 bits (coded by the UVLC) in the picture header. LOOP & POSTFILTERING FOR H.26L

Q15-K-22 (M. Hong, Soongsil University; Y. Park, LG Electronics) discusses the need of loop/post deblocking filter for H.26L. Q15-K-23 (M. Hong, Soongsil University; Y. Park, LG Electronics) proposes replacing the current in-loop filter of the H.26L TML with a filter constructed as a hybrid - being a loop filter coupled with a post

November 2000 Vol. 11.10 Copyright © CSR 2000 13 COMMUNICATIONS STANDARDS REVIEW filter. The proposal was reported to provide a reduction in complexity (at least for the in-loop portion of the new filter) with similar perceptual end-result performance (including both the new in-loop and post-processing filters). Q15/16’s initial reaction to this was to stay with an in-loop design rather than move some part of the designed process outside of the prediction loop. This would avoid the likelihood of it moving outside of the scope of the standard and thus outside of the quality constraints imposed by the standard. At least some minimal degree of quality should be demonstrated with in-loop processing before considering further outside-the-loop enhancement. Thus, Q15/16 was more interested in finding a way to decrease the complexity of the filtering process while retaining that process within the prediction loop. Only if this goal cannot be sufficiently achieved will they plan to change that intent. This proposal was not adopted in its present form; perhaps a modified form of the proposed method will provide the desired design. TEST MODEL, SOFTWARE DEVELOPMENT, AND ENCODING See also Data Partitioning above. H.223/ANNEX B & D “PSEUDO-MUX” TEST MODEL SOFTWARE

Q15-K-15 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, S. Purreiter, Siemens) includes test software for simulation of the effect of H.223 Annex B and D multiplex use over error prone channels on video data streams, including the effect of H.223 Annex D Reed-Solomon forward error correction coding. This software was provided as an upgrade of prior software submitted to the group (Q15-G-42). Q15/16 appreciated having this software available to simulate the effect of some mobile channels on video data streams; it could be a valuable tool for future work. H.324/M TEST CONDITIONS

Q15-K-16 (T. Stockhammer, Munich University of Technology; J. Pandel, G. Bäse, S. Purreiter, Siemens) specifies a set of test conditions for examining the effect of H.324/M terminal operation over error prone channels. These test conditions emphasize measurement of the impact of H.223 Annex D Reed-Solomon forward error correction coding with prioritization on video streams. Q15/16 considered this contribution valuable in the context of designing a test method for its stated environment. However, few (if any) prevalent implementations of this type of H.324/M terminal system are currently anticipated, as the H.223 Annex D design this contribution emphasizes appears not to have been widely embraced by industry. As a result, significant testing for this environment does not appear critical for Q15/16 work at this time. WORKPLAN FOR H.263 The H.263 Schedule is shown in Table 1.

Meeting Date Type Milestone Q15-K Aug ‘00 Experts Alteration of Appendix II to Annex X SG16-1 Nov ‘00 Study Group Decision Annexes U, V, W Qxx-L Jan ‘01 Experts Final Draft for Decision Qxx-M Spring ‘01 Decision Annex X Approval Test Model Appendix II Table 1. H.263 Workplan WORKPLAN FOR H.26L

FUTURE WORK, KTAS , AND FUNCTIONALITY AREAS

Since the TML-5 was defined in this meeting, technical proposals for future meetings should compare their performance against the algorithm described in the latest TML document (Q15-K-59), or at least with the latest software available from the software coordinator. Q15-K-58 (S. Wenger, Technical University of Berlin) contains a schedule for coordination of the TML software development work. It also discusses a few items that were accepted to the test model earlier, but are not yet implemented in the common codebase. It was strongly requested that the contribution of technical proposals should clearly describe which part of the TML should be changed and specifically how the TML should be changed for incorporating the proposed technology.

A new development at this meeting is the proposed development policy for H.26L (Q15-K-55). Experts were asked to comment by the first meeting of 2001 on the appropriateness of adopting this policy to govern future Q15/16 work. Features previously approved for adoption into the TML but not yet fully acted upon include: • B pictures (some form of this is in the document, but none is in the software) • Slice structured coding • Data partitioning • Packetization for IP use • H.263 Annex U, Enhanced reference picture selection (ERPS) capability New changes approved for adoption into the TML include: • Greater picture size flexibility • Mobile-oriented packetization • Loop filter modification (Q15-K-35) • Motion vector prediction modification (Q15-K-34) • Temporal decoupling of display and decoding processes (Q15-K-38) • Modified direct bi-directional prediction for B pictures (with 4 bits in picture header) (Q15-K-44) Shortcomings of TML-5 taken as action items to evaluate and correct include: • Quantizer step size control - Step size change on macroblock by macroblock basis - Check the step control specified (currently 12% increase per increment) • Investigating fully-specified responses to lost or corrupted data The technical areas for further improvement were discussed. A core experiment was designed for further investigation of adaptive integer transforms (Q15-K-57). Q15/16 reviewed the prior list of H.26L KTAs and identified the following seven KTAs for H.26L development: Inter frame prediction motion handling • Improved motion compensation accuracy - Increased motion vector accuracy - Pixel interpolation scheme • Affine motion model - Adoption of six parameter affine motion model - Control grid warping method - Combination with block MC • Supported block segmentation strategies Inter frame residual coding (also applicable to Intra texture coding) • VQ, wavelet, variable block-size residual coding method - Adoption of wavelet coding - Variable size transforms - Integer transforms Intra frame coding • Enhanced Intra coding performance - Improvement of prediction in Intra coding - Adoption of wavelet coding method Entropy coding • Improvement of entropy coding - Efficient mapping of VLC table indexes - Alternative VLC tables Error resilience • Consideration of error resilience - Specification of error resilient decoding - Consideration of multiple description coding (MDC) techniques

- Consideration of interworking with media-specific unequal error protection adaptation layer The list of H.26L functionality areas were kept unchanged from Q15-H-07, as described below. Functionality areas to be covered: (a) High compression performance - Capable of 50% or greater bit rate savings from ‘98 H.263v2 (with Annexes D, F, I, J, and T) at all bit rates (b) Simplification “back to basics” approach - Adoption of a generally simple, straightforward design using well-known building blocks - For example, use of a minimal number of VLC tables (e.g., one) for all parameters to be coded (c) Flexible application to delay constraints appropriate to a variety of services - Low delay (e.g., no B pictures) for real-time conversational services - Higher delay usage appropriate for storage or sever-based streaming application (d) Error resilience - Packet loss resilience - Mobile channel corruption resilience (e) Complexity scalability in encoder and decoder - Asymmetry of encoder and decoder processing complexity - Scalability between amount of encoder processing and achievable quality (f) Full specification of decoding (no mismatch) - Resolve mismatch problem (e.g., integer transform, VQ,…) (g) High quality application - Performance improvement in higher bitrate - Applicability to entertainment-quality applications (h) Network friendliness - Ease of packetization - Information priority control - Application to video streaming services SCHEDULE OF H.26L PROJECT The H.26L workplan schedule was kept largely unchanged as provided below in Table 2. One change made at this meeting was to postpone the date targeted for final major feature adoptions. The actual schedule will depend on the progress of work and can be modified in either direction as events develop.

Meeting Date Type Milestone Q15-K Aug ‘00 Experts SG16-1 Nov ‘00 Study Group Qxx-L Jan ‘01 Experts Final Major Feature Adoptions Jul ‘01 Experts Aug ‘01 Study Group Determination Oct ‘01 Experts Bug-Checking Jan ‘02 Experts White Document Generation May ‘02 Study Group Decision Table 2. H.26L Workplan PLANS FOR FUTURE WORK, AND AD HOC COMMITTEE DESIGNATIONS The future work plans for the H.263++ and H.26L projects, and for deployment of prior Q15/16 video codec standards, were briefly reviewed. The following ad hoc committees were established to progress the work in the interim to the next meeting: Test Model and Software Development S. Wenger H.263 Development G. Sullivan H.26L Development G. Sullivan H.26L Network Adaptation Layer Definition T. Stockhammer Gary Sullivan, Microsoft

ROSTER OF Q15/16 RAPPORTEURS MEETING, AUGUST 22 – 25, 2000, PORTLAND, OR Gary Sullivant, Microsoft Q15/16 Rapporteur

Canada Univ. of British Columbia Anthony Joch [email protected] Finland Nokia Mobile Phones Miska Hannuksela [email protected] Finland Nokia Research Center Marko Luomi [email protected] Germany Deutsche Telekom T-NOVA Peter List [email protected] Germany Heinrich Hertz Institute Guido Heising [email protected] Germany RWTH Aachen Univ. Mathias Wien [email protected] Germany Siemens AG Gero Bäse [email protected] Germany Siemens AG Thomas Stockhammer [email protected] Germany TELES AG / TU Berlin Stephan Wenger [email protected] Germany University of Hannover Thomas Wedi [email protected] Italy Aethra Telecomunicazioni Roberto Flaiani [email protected] Japan NEC Yoshihiro Miyamoto [email protected].nec.co.jp Korea ACS Technology Chul-Woo Kim [email protected] Korea LG Electronics Byeong-Moon Jeon [email protected] Korea Samsung Electronics K.-Y. Yoo [email protected] Korea SoongSil Univ. Min-Cheol Hong [email protected] Korea Sungkyunkwan Univ. Byeungwoo Jeon [email protected] Norway Tandberg Telecom AS Tom-Ivar Johansen [email protected] Norway Telenor Broadband Services Gisle Bjøntegaard [email protected] Sweden Ericsson Radio Systems AB Per Fröjdh [email protected] Sweden Ericsson Radio Systems AB Rickard Sjöberg [email protected] UK BT Labs Mike Nilsson [email protected] UK Essential Viewing Systems Richard Fryer [email protected] USA Apple Computer Hsi-Jung Wu [email protected] USA C-Cube Diego de Garrido USA C-Cube Chad Fogg [email protected] USA C-Cube Didier Le Gall [email protected] USA FastVDO, Inc. Pankaj Topiwala [email protected] USA FastVDO, Inc. Trac D. Tran [email protected] USA GlobeSpan Eric Viscito [email protected] USA Intel Corporation Ram Rao [email protected] USA Intervideo Chang-Su Kim [email protected] USA Microsoft Sridhar Srinivasan [email protected] USA Microsoft Gary Sullivan [email protected] USA Motorola David Baylon [email protected] USA Nokia Research Center Jani Lainema [email protected] USA Packet Video Corp. Maximilian Luttrell [email protected] USA Packet Video Corp. Bo Xie [email protected] USA PictureTel Qunshan Gu [email protected] USA PictureTel MrDavid Lindbergh [email protected] USA PictureTel Patrick Luthi [email protected] USA Polycom Michael Horowitz [email protected] USA Real Networks Gary S. Greenbaum [email protected] USA Real Networks Karl Lillevold [email protected] USA Sharp Labs of America, Inc. Louis Kerofsky [email protected] USA Sharp Labs of America, Inc. Shijun Sun [email protected] USA Sorenson Technologies, Inc. Kyminh Liang [email protected] USA Sorenson Technologies, Inc. Kui Zhang [email protected] USA Toshiba Corp. Barry Aronson [email protected] USA UC, Los Angeles Adam Li [email protected]

November 2000 Vol. 11.10 Copyright © CSR 2000 17 COMMUNICATIONS STANDARDS REVIEW REPORT ON THE ITU-T WORLD TELECOMMUNICATION STANDARDIZATION ASSEMBLY, SEPTEMBER 27 – OCT0BER 6, 2000, MONTREAL, CANADA The ITU-T held its World Telecommunication Standardization Assembly (WTSA), to review the ITU-T progress, and revise the structure and working methods as required to meet the new challenges now facing the ITU-T. Over 600 delegates attended from 80 countries. The following report covers key outcomes, particularly those of interest to CSR readers. IMT – 2000 AND BEYOND

In recognition of the crucial need for more focus on standards for mobile communications, a new Special Study Group (SSG) was established to address studies on IMT-2000 and beyond. The aim of this new SSG is to promote network inter-operability among third generation mobile systems by working with other SDOs, Partnership Projects, etc. It will also start to address requirements for fourth generation mobile systems. Some more flexible working methods were agreed to allow this SSG to operate in a more flexible and responsive method. These are documented in new Recommendation A.9 (see URL below) and include: • Maximum use of electronic working; • Use of teleconferences rather than physical meetings; • Physical meetings announced electronically with a minimum of one month’s notice; • The SSG can investigate producing output documents other than Recommendations, and make proposals to TSAG accordingly. THE ROLE OF TSAG

The Telecommunications Standardization Advisory Group (TSAG) was given additional authority to revise the ITU- T structure and procedures between meetings of the WTSA. In effect, some of the powers of the WTSA have now been delegated to TSAG. These include the authority to establish or close Study Groups, the revision of Study Group working methods, and the revision of the Recommendation approval processes. With this new authority, TSAG can ensure that the ITU-T will now be more responsive to the demands of the standards community, and consequently to changes in market demands. THE NEW ALTERNATIVE APPROVAL PROCEDURE

A new approval procedure has been agreed for ITU-T Recommendations which do not have any regulatory or policy implications. The approval process can be initiated at a meeting of a Study Group or Working Party as before, but can then proceed electronically by correspondence, with approval of the Recommendation occurring as soon as two months after initiation of the procedure. The option exists for a comment resolution period followed by a further additional review. If this correspondence process is not completed successfully, the Recommendation is sent back to the Study Group for resolution of remaining issues and approval, in a manner similar to the traditional approval process. The details of this new approval procedure are available in Recommendation A.8 (see URL below). ITU-T M EMBERSHIP

It is now possible to join the ITU-T as an Associate and participate in the work of a single Study Group for a reduced membership fee. This reduced fee is one sixth of a contributory unit and is approximately $6,000. Details will be available on the ITU web site. TERM LIMITS

The limit of eight years has been set on the term of office of Study Group Chairs and Vice-Chairs, and for the Chair and Vice-Chair of TSAG. STUDY GROUP STRUCTURE: STUDY GROUP 8

SG 8 has been terminated and all the facsimile work has been transferred to Study Group 16. Further comments are included in the SG 16 section below. There were no SG 8 Recommendations presented for approval by the WTSA. Recommendations which have already been Determined by SG 8 will be considered for approval by the next meeting of SG 16 (November 13-17, 2000).

STUDY GROUP STRUCTURE: STUDY GROUP 15

The title for SG15 has been changed to “Optical and Other Transport Networks.” The mandate and responsibilities of SG 15, as proposed by TSAG, were approved by WTSA 2000. SG15 also took on some additional responsibilities with the transfer into SG15 of two Questions previously addressed in SG13: • Q.F/13 - Support for Recommendations specifying systems based on ISDN physical layers • Q.K/13 - Network synchronization and time distribution performance SG 15 is also Lead Study Group on Access Network Transport and on Optical Technology. There was no change to the work program with respect to the work on xDSL and the home networking Recommendations. There was no discussion about G.pnt. The following SG 15 Recommendations were approval by the WTSA: Rec. No. New/ Title Location Rev. Annex H to N Specific requirements for a synchronized symmetrical DSL (SSDSL) system COM 15-R 63 G.992.1 operating in the same cable binder as ISDN as defined in G.961 Appendix III G.705 N Characteristics of Plesiochronous Digital Hierarchy (PDH) Equipment COM 15-R 70 Functional Blocks G.783 R Characteristics of Synchronous Digital hierarchy (SDH) Equipment COM 15-R 75 Functional Blocks G.806 N Characteristics of Transport Equipment – Description Methodology and COM 15-R 76 Generic Functionality I.731 R Types and general characteristics of ATM equipment COM 15-R 76 I.732 R Functional characteristics of ATM equipment COM 15-R 76 Annex D to N Library of Atomic functions COM 15-R 77 I.732 G.707/ R Network Node Interface for the Synchronous Digital Hierarchy (SDH) COM 15-R 71 Y.1322 G.650 R Definition and test methods for the relevant parameters of single-mode fibers COM 15-R 80 G.652 R Characteristics of a single-mode optical fiber cable COM 15-R 80 G.653 R Characteristic of a dispersion shifted single-mode optical fiber cable COM 15-R 80 G.654 R Characteristics of a cutoff-shifted single-mode optical fiber cable COM 15-R 80 G.655 R Characteristic of non-zero dispersion shifted single-mode optical fiber cable COM 15-R 80 G.691 N Optical interfaces for single-channel STM-64, STM-256 and other SDH COM 15-R 82 systems with optical amplifiers G.972 R Definition of terms relevant to optical fiber submarine cable systems COM 15-R 82 G.975 R Forward error correction for submarine systems COM 15-R 82 G.976 R Test method applicable to optical fiber submarine cable systems COM 15-R 82 G.871/ N Framework of Optical Transport Network Recommendations COM 15-R 82 Y.1301 The new management team for SG 15 will be: Chairman: P. Wery (Nortel Networks, Canada) Vice-Chairmen: G. Bonaventura (Telecom Italia, Italy) S. Trowbridge (Lucent Tech., USA) H. Okamura (NEC, Japan) STUDY GROUP STRUCTURE: STUDY GROUP 16

The only change to the work program of SG16 was the addition of the facsimile work from SG8. The majority of this work will now be handled by a single new Question in SG16 which is a combination of the Questions A, B, and C/8 (formerly Questions 1/8, 4/8, and 5/8) which were proposed by SG8. The work under the proposed Q.D/8 (formerly Q6/8) will be handled within the SG 16 proposed Q.E/16 on media coding.

The new SG 16 project on multimedia coordination “Mediacom 2004” was endorsed by the WTSA. The objective of project Mediacom 2004 is to create a framework for the harmonized and coordinated development of multimedia communication standardization for use across all ITU-T and ITU-R Study Groups, and in close cooperation with other regional and international SDOs and industry forums.

In addition to being Lead SG on multimedia issues, SG16 was also appointed as Lead SG on e-commerce and e- business. However, SG13 remains the Lead SG on IP matters.

No Recommendations were proposed by SG16 for approval by the WTSA. The new management team for SG 16 will be: Chair: P-A Probst (Swisscom, Switzerland) Vice-Chairs: S.F. de Campos Neto (Brazil) J. Magill (Lucent Tech., UK) M. Matsumoto (Waseda/NTT, Japan) F. Tosco (CSELT, Italy) M.Y. Wreikat (Jordan) SUMMARY OF RESOLUTIONS AND RECOMMENDATIONS APPROVED BY WTSA 2000 The documents below are now available publically, and free of charge from the ITU web site: and

RESOLUTIONS

Number Title 1 (rev) Rules of procedure of the ITU-T 2 (rev) Study Group responsibilities and mandates 7 (rev) Collaboration with the ISO and the IEC 11* Collaboration with the Postal Operations Council (POC) of the Universal Postal Union (UPU) in the study of services concerning both the postal and telecommunication sectors 17* Telecommunication standardization in relation to the interests of developing countries 18 (rev) Principles and procedures for the allocation of work to, and coordination between, the Radiocommunications and Telecommunication Standardization Sectors 20 (rev) Procedures for allocation and management of international numbering resources 22 (rev) Authorization for TSAG to act between WTSAs 26 (rev) Assistance to Regional Tariff Groups 29 (rev) Alternative calling procedures on international telecommunication networks 31 (new) Admission of entities or organizations to participate as Associates in the work of ITU-T 32 (new) Strengthening the use of EDH for the work of the ITU-T 33 (new) Guidelines for ITU-T strategic activities 34 (new) Voluntary contributions 35 (new) Appointment and maximum term of office for chairmen and vice-chairmen of ITU-T Study Groups and of the TSAG 36 (new) ITU Reform 37 (new) Alternative approval process for ITU-T 38 (new) Coordination among ITU-T, ITU-R and ITU-D for IMT-2000 activities 39 (new) The changing role of the WTSA 40 (new) Regulatory aspects of ITU-T work 41 (new) Accounting rate principles for international telephone services

*Resolutions 11 & 17 have been re-issued without changes.

RECOMMENDATIONS

Number Title A.1 (rev) Work methods for study groups of the ITU-T A.2 (rev) Presentation of contributions relative to the study of Questions assigned to ITU-T A.4 (rev) Communication process between ITU-T and fora and consortia A.6 (rev) Cooperation and exchange of information between ITU-T and national and regional standards development organizations A.7 * Focus Groups: working methods and procedures A.8 (new) Alternative approval process for new and revised Recommendations A.9 (new) Provisional working procedures for the special study group on IMT-2000 and beyond A.11 (new) Publication of ITU-T Recommendations and WTSA proceedings A.12 (new) Identification and layout of ITU-T Recommendations A.13 (new) Supplements to ITU-T Recommendations

*Recommendation A.7 is unchanged from that approved by TSAG in June 2000.

Communications Standards Review regularly covers the following committee meetings:

TIA TR-30 Data Transmission Systems & Equipment TR-41 User Premises Telephone Equipment Requirements ITU-T SG15 WP1 Network Access SG15 WP2 Network Signal Processing SG16 Multimedia ETSI AT Access and Terminals TIPHON Voice over Internet TM6 Transmission & Multiplexing DSL Forum xDSL, Access Technologies

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November 2000 Vol. 11.10 Copyright © CSR 2000 21 COMMUNICATIONS STANDARDS REVIEW REPORT OF ETSI ACCESS AND TERMINALS (AT) COMMITTEE MEETING OCTOBER 9 – 13, 2000, SOPHIA ANTIPOLIS, FRANCE This was the second meeting of the new Access and Terminals Committee; TD-01 is the agenda. N. Encarnação (OFCOM) is the Chair. Forty-two members attended from fourteen different countries; most are listed in TD-02. TD-03 is the AT Chair’s report of this meeting. TD-05 contains the ETSI IPR policy. TD-13 sets out the procedure for approval by correspondence in AT. B. Martensen (Ericsson) was unable to attend due to illness; the WG Analog sessions were chaired by N. Encarnação. Following the request of the ETSI Board that TC AT should merge with TC SPAN by the end of the year, M. Briggs (BT), the SPAN Chair, gave a presentation on the recent reorganization of SPAN. He set out proposals for incorporating TC AT into its new structure (TD-77, TD-78). He invited TC AT members to attend the next meeting of SPAN to determine what synergy might exist (TD-79). ETSI SPAN has adopted a new structure and meeting arrangements. TD-77 identifies the following areas where SPAN will start new activities: • Adaptation and standardization of the Megaco and H.248 protocols and packages for network (core and access) and terminals. • Adaptation and standardization of SIP / SDP protocol and extension for networks (core and access) and terminals. • Adaptation and standardization of the SIGTRAN protocols for the support of reliable signalling transport for networks (core and access). • Consideration of the standardization of the security aspects relating to the signalling transport protocols. • Consideration of the impact on protocols: - For NAT (Network Address Translation) and ENUM (tElephone NUmbering Mapping) in the context of network security and the network access from terminals and firewalls. - For network address and naming translation policies. - For regulatory requirements (e.g. CLI and emergency services). - For QoS level provisioning and related control protocols. • Standardization of control protocols for advanced access network including xDSL technologies. • Evolution of ISDN / PSTN networks for interoperability of services for fixed and mobile networks using common protocols (e.g., 3GPP and TIPHON). It was noted that recent Board proposals on the merger of micro committees had failed and it had been agreed to cease the use of committee performance indicators. TD-08 (N. Encarnação, OFCOM) is a proposed liaison to the Board requesting that TC AT continue to operate as an independent TB; it was condemned as being too wordy and politically undesirable. A considerably revised and shortened version of TD-08 was approved to be sent to the Board. TD-40 (N. Encarnação, OFCOM; M. Briggs, BT) presents a preliminary mapping of common AT/SPAN interest areas; TD-39 (N. Encarnação, OFCOM; M. Briggs, BT) identifies those areas within the timetable of the November SPAN meeting. TD-12 (I. Marshall, Nortel) presents arguments against the proposed AT/SPAN merger. H. Carr (BABT) suggested that the arrangements in SPAN would only benefit large companies able to support many representatives. I. Marshall (Nortel) complained that the SPAN organization requires dedicated standardizers and does not fit representatives with other responsibilities. It was noted that fewer people are attending SPAN meetings under the current arrangements; M. Briggs, SPAN Chair, admitted that the three main meetings per year were largely devoted to rubber stamping and dealing with cross working group issues that arise in other working group meetings. TD-07 (N. Encarnação, OFCOM) presents information on new CEC regulations (networks and services). It contains a copy of a CEC press release noting the EC’s adoption of a package of legislative proposals to overhaul the rules for electronic communication. The most relevant text for AT contained in this contribution are the following proposals for directives of the European Parliament and of the Council on: • A common regulatory framework for electronic communications networks and services • Universal service and users’ rights relating to electronic communications networks and services • Unbundled access to the local loop TD-67 is a liaison from TIPHON informing of their current work items.

ANALOG WORKING GROUP

SAFETY DOCUMENTS

WG Analog, led by N. Encarnação (OFCOM), amended the 20 draft ETSI documents listed below (TD-29). These amendments were necessary due to the removal of safety and EMC requirements, and to changes in the regulatory regime. Some regulatory references were also removed, and the clarity was improved: • EN 300 247 specifies the technical requirements and test principles for connection characteristics of ONP 2,048 kbit/s digital unstructured leased lines. • EN 300 248 specifies the full physical and electrical characteristics and corresponding test principles for a terminal equipment interface for connection to the network termination points of ONP 2,048 kbit/s digital unstructured leased lines using 120 W interfaces. • EN 300 288 specifies the technical requirements and test principles for the network interface presentations of ONP 64 kbit/s digital unrestricted leased lines with octet integrity; these presentations are codirectional. • EN 300 289 specifies the technical requirements and test principles for the connection characteristics of ONP 64 kbit/s digital unrestricted leased lines with octet integrity. The leased line provides access to the full digital bit rate of 64 kbit/s, with network timing for both directions of the transmission, with no restrictions on the binary content. • EN 300 290 specifies the full physical and electrical characteristics and corresponding test principles for a terminal equipment interface for connection to the network termination points of ONP 64 kbit/s digital unrestricted leased lines with octet integrity. • EN 300 418 specifies the technical requirements and test principles for the network interface presentations of ONP 2,048 kbit/s digital leased lines using 120 W interfaces. This includes: - The 2,048 kbit/s digital unstructured leased line - The 2,048 kbit/s digital structured leased line with an information transfer rate of 1,984 kbit/s without restriction on binary content. • EN 300 419 specifies the technical requirements and test principles for connection characteristics of ONP 2,048 kbit/s digital structured leased lines. The leased line operates at 2,048 kbit/s and provides an information transmission capability, without restriction on binary content, of 1,984 kbit/s. The remaining 64 kbit/s provides an 8 kHz framing structure in accordance with ETS 300 167 and ITU Recommendations G.704 and G.706. • EN 300 420 specifies the full physical and electrical characteristics, the necessary functional characteristics, and the corresponding test principles for a terminal equipment interface for connection to the NTPs of ONP 2,048 kbit/s digital structured leased lines using 120 W interfaces with an information transfer rate of 1,984 kbit/s without restriction on binary content. • EN 300 448 specifies the technical requirements and test principles for the connection characteristics and the physical and electrical characteristics of the network interface presentation of ordinary quality, voice bandwidth, 2- wire, analog leased lines, provided as part of the minimum set under the Council directive on the application of ONP to leased lines (92/44/EEC). • EN 300 449 specifies the technical requirements and test principles for the connection characteristics and the physical and electrical characteristics of the network interface presentation of special quality, voice bandwidth, 2- wire, analog leased lines, provided as part of the minimum set under the Council directive on the application of ONP to leased lines (92/44/EEC). • EN 300 450 specifies the full physical and electrical characteristics and corresponding test principles for a terminal equipment interface for connection to the network termination points of ONP ordinary quality or special quality voice bandwidth 2-wire analog leased lines defined by EN 300 448 and EN 300 449. • EN 300 451 specifies the technical requirements and test principles for the connection characteristics and the physical and electrical characteristics of the network interface presentation of ordinary quality, voice bandwidth, 4- wire, analog leased lines, provided as part of the minimum set under the Council directive on the application of ONP to leased lines (92/94/EEC). • EN 300 452 specifies the technical requirements and test principles for the connection characteristics and the physical and electrical characteristics of the network interface presentation of special quality, voice bandwidth, 4- wire, analog leased lines, provided as part of the minimum set under the Council directive on the application of ONP to leased lines (92/94/EEC). • EN 300 453 specifies the full physical and electrical characteristics and corresponding test principles for a terminal equipment interface for connection to the network termination points of ONP ordinary quality or special quality voice bandwidth 4-wire analog leased lines defined by EN 300 451 and EN 300 452. • EN 300 686 specifies the technical requirements and conformance tests for the network interface presentations of 34 Mbit/s and 140 Mbit/s digital leased lines. This includes:

- The 34 Mbit/s digital unstructured leased line operating at 34,368 kbit/s - The 140 Mbit/s digital unstructured leased line operating at 139,264 kbit/s - The 34 Mbit/s digital structured leased line operating at 34,368 kbit/s for the support of an unstructured 33,920 kbit/s information transfer rate - The 140 Mbit/s digital structured leased line operating at 139,264 kbit/s for the support of an unstructured 138,240 kbit/s information transfer rate • EN 300 687 specifies the technical requirements and conformance tests for connection characteristics of point-to- point 34 Mbit/s digital leased lines. These leased lines operate at: - 34,368 kbit/s providing an information transmission capability, without restriction on binary content (D34U) - 34,368 kbit/s providing an information transmission capability, without restriction on binary content, of 33,920 kbit/s (D34S); the remaining 448 kbit/s provides an 8 kHz framing structure in accordance with ETS 300 337 (ITU-T Recommendation G.832) • EN 300 688 specifies the technical requirements and conformance tests for connection characteristics of point-to- point 140 Mbit/s digital leased lines. These leased lines operate at: - 139,264 kbit/s providing an information transmission capability, without restriction on binary content (D140U) - 139,264 kbit/s providing an information transmission capability, without restriction on binary content, of 138,240 kbit/s (D140S); the remaining 1,024 kbit/s provides an 8 kHz framing structure in accordance with ETS 300 337 (ITU-T Recommendation G.832) • EN 300 689 specifies the full mechanical and electrical characteristics, the necessary functional characteristics, and the corresponding conformance tests for a terminal equipment interface for: - Connection to the network termination points of 34,368 kbit/s digital unstructured leased lines (D34U) - Connection to the network termination points of 34,368 kbit/s digital structured leased lines (D34S) which support an unstructured 33,920 kbit/s information transfer rate These leased lines are defined in EN 300 686 and EN 300 687. • EN 300 690 specifies the full mechanical and electrical characteristics, the necessary functional characteristics and the corresponding conformance tests for a terminal equipment interface for: - Connection to the network termination points of 139,264 kbit/s digital unstructured leased lines (D140U) - Connection to the network termination points of 139,264 kbit/s digital structured leased lines (D140S) which support an unstructured 138,240 kbit/s information transfer rate These leased lines are defined in EN 300 686 and EN 300 688. • EN 300 766 specifies the technical requirements and test principles for the connection characteristics and network interface presentations of a 64 kbit/s point-to-point digital unrestricted leased line with octet integrity that is provided between either two 2,048 kbit/s structured network interfaces or a 2,048 kbit/s structured network interface and a 64 kbit/s codirectional network interface. WG Digital also discussed these same 20 documents; they agreed on a policy to deal with them which differed from that of WG Analog. In a joint session between these two WGs, it was agreed to obtain final approval of the documents via postal vote to give all members time to study the revisions. TD-68 and TD-69 contain the intended final versions of these 20 documents. In plenary session it was decided to allow two weeks for TC AT to approve the changes before they were sent out for one-month’s approval by correspondence (one-step approval procedure). It was also agreed to inform TC Safety of these actions. The plenary provisionally approved the following five work items necessary to improve the safety related text following a liaison received from TC Safety: • TD-50 (REN/AT-020012), for revision of ETS 300 247 • TD-51 (REN/AT-020013), for revision of ETS 300 289 • TD-52 (REN/AT-020014), for revision of ETS 300 419 • TD-53 (REN/AT-020015), for revision of ETS 300 687 • TD-54 (REN/AT-020016), for revision of ETS 300 688 W. Mellors (ANEC) drew members’ attention to TD-35, a press release from ANEC informing on the ANEC Guide for product design and testing. This document aims to help both designers and testing houses of products and services identify and include the needs of older persons and persons with disabilities. This document is available at . G. Ochel (ETSI, as Secretary of the JPG, the Joint Presidents Group of CEN/CENELEC/ETSI) gave a presentation on eEurope at one of the joint sessions, explaining the Commission’s intention to encourage a cheaper, faster, and secure Internet, to invest in people and skills, and to stimulate use of the Internet. He drew attention to a joint

CEN/CENELEC/ETSI activity to produce a rolling action plan to speed up Internet activities with Commission financial support. He asked TC AT to inform him of its activities with eEurope implications. ATAAB A joint session dealt with the format of ATAAB (analog type approval advisory board) advisory notes. N. Encarnação (OFCOM) presented his proposals for the handling of Advisory Notes (AN, TD-28). TD-56 (N. Encarnação, OFCOM) contains an exchange of messages between N. Encarnação and D. Barry, the ETSI TRAC Chair. N. Encarnação drew attention to the draft advisory note on automatic dialing with dial tone detection (TD-24), for the Czech Network, and noted that two other Czech Network ANs are being discussed between B. Martensen (Ericsson, WG Analog Chair) and Z. Gutter (Czech expert). He also noted that AT decided earlier to follow the xTAAB criteria, but that it took some time for the most concerned experts to understand that using the same exact format as xTAAB facilitates a clearer separation between the R&TTE (in EU) and 98/13 (at present in some other countries) regimes. Further, he proposed that no AN technical information on ETSI deliverables be published before TRAC decides and publishes the information on the TRAC server. D. Barry (ETSI TRAC Chair), in TD-56, notes his receipt of three draft ANs for use with TBR 21 and EN 301 437 when these standards are applied by designers for terminals intended for use in the Czech Republic (TD-56 contains these ANs). To aid designers, and to support the efforts of the Czech Telecommunication Office, he has uploaded the proposed ANs as Zip files on the Members side of the TRAC website, in the folder: ATAAB_Docs/Advisory Notes/Development. He asks that AT consider whether these proposed ANs are technically appropriate, i.e., consistent, technically relevant, etc.; if so, he will begin the formal process of TRAC consideration toward raising their status to current ANs, upon which he will make them available in the TRAC Members file: ATAAB_docs/Advisory Notes/Current, and via the public side of the TRAC site. TD-27 (N. Encarnação, OFCOM) is a proposed format of the ANs in the form of a TR. It gives guidance on the application of TBR 21, and is therefore applicable to terminal equipment falling within the scope of TBR 21 with automatic dialing facilities implemented according to clause 4.8.1.2 of TBR 21 and intended to be connected in the Czech Republic. TD-25 (ETSI) is a draft listing of ANs; it is intended to be an overview of all the parts of the TR 103 016 series of documents and should be used together with each single part or sub-part of this series. Members opposed the change of format; they preferred to retain the ATAAB format. It was agreed to continue the ATAAB method of working until TRAC ceases to exist. J. Long (DTI) insisted on removal of the phrase in the ATAAB format suggesting that TC AT is acting on behalf of TRAC. He also explained the difference between an endorsed advisory note (designated AN), wherein ATAAB supports the technical content, and notes that are not endorsed, in the case of ATAAB not being convinced of their technical merit. Such notes are published with a national designation (e.g., CZ) indicating the country of origin. It was noted that EG 201 121, the guide to the application of TBR 21, will need updating from time to time. Z. Gutter (Czech Telecommunication Office) presented the technical content of TD-24, automatic dialing with dial tone detection and noted the many different dial tone implementations in the Czech Republic; it received minor amendment, and was approved as TD-84 (AN 18). TD-63, on loop current characteristics, with simplifying amendment, was approved as TD-85 (AN 20). TD-64, on DTMF signaling: tone and pause duration, was also approved, following amendment, as TD-86 (AN 19). TD-65 proposes an advisory note calling for a change of the DC characteristics which reduces the 9 V limit at low currents to 8 V. This note was not supported, mainly as similar proposals from Spain and Germany had not been endorsed by ATAAB. The Czech Republic agreed that the proposal should be put forward as a non-endorsed note as CZ 01 (TD-87). ES 301 235 1-4 (DTMF) TD-62 (R. Gandvik, Telia) points out that ES 201 235 does not provide a complete set of requirements for all applications intending to use DTMF signaling, notwithstanding the statement in its scope that it does; a number of problems in digital environments were not dealt with. TD-62 notes that the transmitter function in a digital local exchange is a digital device and the output level from such a device is in general expressed in dBm0. Knowing the relative output level of the analog line circuit, the dBm0 can be converted to the dBV level across ZR as given in 4.2.2 of ES 201 235-2. However, sending of DTMF for display services, in general takes place during on-hook so the actual sending levels will be substantially higher (e.g., 6 dB). Also the PSTN receiving of DTMF dialing from a digital PBX is not covered by ES 201 235-3 (receiver specification). Requirements for such receiving may still be found in clause 4 of ETR 206.

It was agreed that a contribution should be submitted to the next SPAN meeting to determine their intent on ETRs 206 and 207. P. Dofnas (Ericsson) agreed to assess whether ES 201 235 is suitable for use by the Commission in the proposed new directive on Universal Service. RINGING GENERATION

TD-43 (P. Erasmus, Telkom SA) is draft v.0.1.3 of TR 101 768, PSTN; Study on the generation of analog ringing signals; it contains changes resulting from comments made at the previous meeting. All references to “type approval testing” had been changed to “conformance testing,” and the wording in general had been changed to a positive form to show how to ensure correct operation. After discussion, minor changes were made; the amended version was agreed for publication by the plenary, where it was also agreed to upgrade the document to an ETSI Guide under a new WI (TD-90). POTS/ADSL SPLITTERS

TD-44 (B. van Leerdam, KPN) is the input version (v.0.0.6) of the draft TR 101 728, Study for the specification of the low pass section of POTS/ADSL splitters; it contains modifications from the June meeting. This draft was submitted to the September TM 6 meeting; it produced the comments contained in TD-45, which proposes some modifications to the text of TD-44 to clarify the fact that the splitters, and the filters of the distributed splitter, are all intended for full rate ADSL. J. Montenot (France Telecom) was of the opinion that this document should still cover ADSL Lite, as it is a TR. It was agreed to add a new sub clause under Clause 6 giving a more detailed description of the distributed splitter. The comments from TD-45 were incorporated. F. Howett (Nortel) pointed out that in 5.13 (Common Mode Impedance) the requirement applies only to the common mode choke case; the text was suitably amended. TD-55 (N. Encarnação, OFCOM) proposes various minor improvements to TR 101 728. It proposes inclusion of a Clause 8.2, “line tests,” with the following text: “It is known that, particularly in cases of unbundled local loops, some difficulties arise from testing the access lines, e.g., who is testing which facility (and how) and what impact does this testing have on other services sharing the physical line. This matter is intended to be submitted to a special study where experiences in different legal surroundings will be analyzed.” This was agreed, but without the reference to legal issues. Related to stability issues, textual modifications were proposed to Clause 5.6.1.1 (Impedance testing at the POTS-port) Table 4 (return loss), and Annex A (Impedance of “non-transparent” splitters) Table 8 (return loss), to align the text for transparent and non-transparent splitters. TD-61 (R. Gandvik, Telia) contains comments and proposed editorial changes to TR 101 728. It was agreed to change all references from “Central Office (CO)” to “Local Exchange (LE)”, as proposed. It was agreed to refer to “voltage drop” instead of insertion loss in 5.3.1. It was agreed to delete 5.7.1, the “one port test” used for splitters which are an integral part of equipment. It was noted that the isolation test requirement was incomplete and new text was added. TD-76 lists the result of the discussion on TR 101 728. TD-88 is the output version (v.0.0.7); the plenary session approved it for publication. THE FUTURE OF TBRS

TD-47 and TD-48 (H. Carr, BABT) are draft (not yet distributed) surveys on the current use of non-radio TBRs, the first to ETSI members, the second to organizations and administrations. AT is conducting a study of the global usage and acceptance of non-radio TBRs and associated documents. This study is being conducted in light of the recent changes in EU legislation, and in consideration of the widespread increasing use of many TBRs outside the EU, including regulatory and non-regulatory aspects and impact by and on other technologies, e.g., ADSL over POTS or ISDN, or IP applications on terminals. The purpose of this study is to focus any future support of the TBRs in the directions required and identify the interested parties. TD-46 (N. Encarnação, OFCOM) is a first draft of TR 101 844, Study of the global usage and acceptance of non- radio TBRs and associated documents. J. Long (DTI) suggested that the subject has implications outside the responsibilities of TC AT and should therefore be dealt with by ETSI as a whole and possibly by the Commission. After discussion, it was generally agreed that others in ETSI had responsibilities for TBRs and would need to be involved. It was also agreed that the report was premature.

At the final plenary, J. Long (DTI) insisted that TD-46 be withdrawn from the server, as it pre-empted TC AT discussion, and that no further reference to it be made. It was finally agreed to send a liaison (TD-81) based on TD- 47 to members of TC AT, ATAAB, ITAAB, and TRAC, with reply solicited within one month. A liaison related to the support for TBRs by AT (TD-80) was also approved to be sent to other TB Chairs through the OCG and to the Board. It was also agreed to send a liaison (TD-82) to the ETSI Board asking that the Board confirm to the worldwide standards community that ETSI will continue to support the users of TBRs by ensuring the future public availability of TBRs in an appropriate manner; the plenary agreed to approve this by correspondence. It was agreed to hold a Rapporteurs meeting Dec. 4-5, 2000, to study the responses to TD-47. OTHER ANALOG ITEMS

TD-18 (duplicated as TD-32) is a liaison from ISO/IEC JTC 1/SC25 on broadband cabling on customer premises. During its June meeting in Tromsø, ISO/IEC JTC 1/SC 25/WG 3 started to study broadband applications with respect to premises cabling. Presently it is open whether new cabling channels are needed or whether existing cabling channels are sufficient to support the broadband applications specified by IEC TC 100. This liaison identifies the most important applications and their requirements, and asks for information on the applications which are under AT responsibility and could make use of broadband premises cabling. J. Long (DTI) suggested that the only applicable area is out-of-band signaling in POTS terminals. It was agreed to not reply at this time, but that the Chair should generate a document to be sent via email before December. TD-17 provides notes and minutes of the September meeting of CENELEC TC 205/WG5 (Home and building electronic systems). It puts forward information and suggestions on residential gateways and asks for feedback. They plan to base their work on ISO/IEC JTC1 SC25 N629 Home electronic system - Residential Gateway (HomeGate) - Part 1: Architecture, and ISO/IEC JTC1 SC25 WG1 N925 (E) - CD 18012-1 Home electronic system - Guidelines for product interoperability - Part 1: Introduction. CENELEC TC 205/WG5 is looking for people to help work toward their goal of producing a useful residential gateway standard by November 2001. This was noted for information. TD-41 (presented by N. Encarnação, Chair) is a proposal for a WI to study the coexistence of in-home LAN technologies, existing home installations, and voice band access networks also using DSL technologies. AT Analog agreed that any such work will spread across the responsibilities of a number of TBs, and should not start until the overall position becomes more mature. It was agreed to send a liaison (TD-83) to other ETSI TBs and ISO/IEC JTC 1/SC25 to inform them of this proposal. DIGITAL WORKING GROUP TD-16 is draft TR 101 731 (v.0.0.8), Publication of interface specification under Directive 1999/5/EC; Guidelines for describing digital interfaces; it was completed, and subsequently approved for publication in plenary session. CABLE NETWORK INTERFACES

TD-36 (S. Kang, Motorola) is draft TR 101 857 (v.R01), Publication of interface specification under Directive 1999/5/EC; Guidelines for describing cable network interfaces. The purpose of this document is to assist the public network operators and public service providers in producing publications that describe their public interfaces in accordance with article 4.2 of Directive 1999/5/EC. TD-30 (I. Marshall, Nortel Networks) emphasizes that the draft TR 101 857 must make clear that CATV systems that are pure broadcast do not fall within its scope; AT Digital must clarify exactly which systems are covered by the TR. TD-31 (I. Marshall, Nortel Networks) notes that TR 101 857 needs to address the position of the NTP, which can vary from operator to operator and from country to country; the TR must address all foreseen possibilities. TD-31 notes two business models where the cable modem is terminal equipment or the cable modem is part of the network infrastructure. TD-34 (S. Kang, Motorola) discusses the scope of TR 101 857, and provides a framework for its structure. S. Kang noted that he was still awaiting inputs from European cable operators; he pointed out that the position of the NTP is dependent on national license agreement. One task in the development of the guidance document is to identify the various network interface points; the description of the network interface will depend on whether the cable modem is considered part of the network or the CPE. Following discussion, it was agreed that, where possible, TR 101 857

November 2000 Vol. 11.10 Copyright © CSR 2000 27 COMMUNICATIONS STANDARDS REVIEW should reference existing guideline documents from TC AT and ERM to avoid unnecessary duplication. A revised draft will be put on the server by the end of the year. TD-42 (presented by S. Kang, Motorola) is a proposal for a new work item to produce a standard for multimedia IP telecommunication services over European broadband cable networks. This work was supported by Broadcom, Motorola, Nortel, and Telewest; a Special Task Force (STF) was requested to carry out the work. It was agreed to send a liaison to other TBs to inform them of this TC AT work item. The WI was subsequently agreed in plenary session. ISDN TECHNICAL ADVISORY AD HOC BOARD (ITAAB) MATTERS

TD-10 (D. Barry, ETSI TRAC Chair) presents the positive decision from TRAC to reassign the TAABs to ETSI AT, and asks the AT Chair to advise TRAC if/when the need is seen to modify any ANs or take any other TAAB actions. For TRAC information: TD-11 (N. Encarnação, OFCOM) informs that both ATAAB and ITAAB have been moved to ETSI responsibility; the TC AT Chair is responsible for drafting any ANs that may be required, for formal approval by TRAC Plenary via correspondence. It was pointed out that DECT, GSM, and TETRA advice notes had not been transferred to ETSI. After discussing the future of IT01, A reference listing of recommendations for the accredited testing and type approval of ISDN terminal equipment, it was decided to leave it unchanged until April 2001, at which time it would probably need to be converted to a TR. TD-06 (J.M. Lescop, France Telecom) suggests the removal of AN 054r4, Additional French attachment requirements for the ISDN. AT Digital WG felt that it should remain available until the last EuroNumeris connection has been removed. TD-14 (S. Frankholz, Siemens) reports that the old BRI chip PEB2080 is still available at Infineon, but is not recommended for new designs; Infineon plans to cancel its production by 2001. It was agreed to take no action beyond informing TRAC of the situation. TD-71 (T. Schildt BAPT) contains an analysis of the technical differences between ETS 300 102-1 (old layer 3) and ETS 300 403-1 (new layer 3), and between ETS 300 125 (old layer 2) and ETS 300 402-1 and-2 (new layer 2), and considers their impact on TBRs 3 and 4. The lists of changes were taken from Annex ZB/ZC of ETS 300 402 and Annex ZA.2, Technical changes of ETS 300 403-1. In discussion, it was noted that TBRs 3 and 4 refer to the ETS 300 100-series of standards, whereas many networks are now being constructed based on the ETS 300 400-series. C. Linford (Natural Microsystems) will draft an application note permitting TBR approval to be based on either series of base standards. It was further agreed that S. Frankholz (Siemens) will revise AN 119, Overvoltage protection to delete references to ETS 300 046 (Primary rate access) and ETS 300 047 (Basic access). IP TERMINALS

TD-26 is draft TR 101 941 (v.0.1.1), Study of the implications of standardization of IP terminals utilizing Ethernet, PSTN, and ISDN connection methods. The purpose of this Technical Report is to identify possible open gaps in the standardization process for IP terminals and to make proposals for new work items. A. Kamcke (Siemens) opposed this document; he held that it leads towards the TIA minimalist approach. It was supported by two Nortel representatives, but F. Howett (Nortel) expressed concern that the work has no focal point within ETSI. E. Hay (Mitel) suggested liaison with the IEEE on powering of terminals. This liaison was opposed by A. Kamcke, who also suggested deletion of Clause 7 dealing with proposals for future work. H. Carr (BABT) pointed out that standards already exist for connection to the PSTN and the ISDN, and that work is needed only for Ethernet connection. It was finally agreed that work should continue on the draft. TD-59 contains comments from A. Kamcke on draft TR 101 941. He asserts that cooperation with IEEE would not be a good idea, noting that IP telephony is not only a new access interface, it opens the door to new opportunities. In spite of these objections, WG Digital agreed to initiate a work item on the powering of IP terminals (TD-72) based on the work carried out in IEEE 802af. The WI was subsequently approved in plenary session.

TD-73 (P. Erasmus, Telkom SA, Rapporteur) is a new WI on general principals for parameters applicable to IP terminals; it describes the characteristics and applications of IP terminals based on information available in existing documents and standards. This was approved in plenary session. OTHER DIGITAL BUSINESS

TD-15 is a liaison from TIPHON WG5, QoS, in reply to a liaison from TC AT (see CSR Vol. 11.8, TIPHON WG5) on the proposed study of TE utilizing IP technology. TIPHON asks TC AT to continue to liase with TIPHON for advice and inputs on standardization issues relating to IP terminals and looks forward to the TC AT deliverables. TIPHON does not have any input to the TC AT study regarding the powering of IP terminals, but any studies relating to IP terminal characteristics/features and voice QoS classes and IP addressing are of importance to TIPHON. TIPHON therefore asks that such specific studies take into account the deliverables from TIPHON to ensure interworking between the TIPHON IP terminal equipment and TIPHON-based IP access networks. FEATURES WORKING GROUP TD-22 (U. Jansson, Telefon AB LM Ericsson) is draft EN 300 778-1 (v.0.4.0), PSTN; Protocol over the local loop for display and related services; Terminal equipment requirements; Part 1: On-hook data transmission. TD-23 (U. Jansson, Telefon AB LM Ericsson) is draft EN 300 778-2 (v.0.4.0), PSTN; Protocol over the local loop for display and related services; Terminal equipment requirements; Part 2: Off-hook data transmission. TD-33 (KPN), TD-37 (Telia), and TD-74 (France Telecom) contain comments on EN 300 778-1. TD-38 (Telia) contains comments on EN 300 778-2. Most of the proposed amendments were accepted and incorporated into revised versions of the two parts of the standard, which were subsequently approved in plenary session to go for vote. The following work items were drawn up to cover the work on test documents and conformance test specifications for the on-hook and off-hook data transmission standards (G. Engström, Telia, Rapporteur): • TD-92, Conformance test specifications for the display services protocol (FSK) over the local loop, Off-hook; Part 7: PICS; Part 8: TSS&TP; Part 9: TTCN • TD-93, Test document for a TE according to EN 300 778-2 (Off-hook); Part 4: Conformance test • TD-94, Test document for a TE according to EN 300 778-1 (On-hook); Part 3: Conformance test • TD-95, Conformance test specifications for the display services protocol (FSK) over the local loop, On hook; Part 4: PICS; Part 5: TSS&TP; Part 6: TTCN TD-09 (A. Kamcke, Siemens) proposes a new WI for user-to-user SMS in PSTN and ISDN; it gives the basic requirements and a short description of a technical solution. The Short Message Service (SMS) is one of the most popular services in mobile communication for text messages with a size up to 160 characters. The number of SMS- messages sent in Germany exceeds one billion per month. In GSM, the Short Message Service works by using a Short Message Service Center. The network operator is not usually the operator of the Service Center. TD-49, describes SMS via the PSTN/ISDN. The main focus of this specification is to describe the interworking and the protocol between the communication device (CD) and the short message service center (SM-SC) via the PSTN/ISDN. The CD is connected to the PSTN/ISDN via an analog or an ISDN access. The short message service center is connected to the PSTN/ISDN via an ISDN primary rate interface. The PSTN/ISDN access of the CD must provide the Caller ID feature. With the information transmitted via the caller ID feature, the CD can detect and accept incoming calls from the SM-SC automatically. After the connection between the CD and the SM-SC has been established, the SM-SC delivers an SMS to the CD. The PSTN/ISDN provider shall also be able to transmit the caller ID of the CD to the SM-SC. The SM-SC needs this information to identify the user and to deliver SMS information in the case that a polling algorithm is used by the CD. The Caller ID information is also required for the billing. TD-66 (W. Schellhaas, T-Nova Deutsche Telekom) provides status and information on uSMS (Universal Short Message Service) within SPAN11 (formerly SPAN2). Two general views arose: one sees a need for a complete service description for uSMS over PSTN/ISDN, the other sees a need for just a short description describing the differences against the GSM standard. It was agreed that SPAN11 will discuss the scope and content of a new draft in November, depending on the result of the AT SMS discussion. From their point of view, a need for a stage-1 service description (in a traditional manner) is only given for a network-based solution; therefore a positive decision from SPAN13 about the following questions is necessary: • Is there sufficient support for the uSMS within SPAN13?

• Is SPAN13 willing to open a new WI and to produce the according documents for uSMS ? • Is there a volunteer in SPAN13 to take over the rapporteur for this new WI ? Features WG discussion identified some potential difficulties of performing such a function completely without special network facilities. The new work item was subsequently approved in plenary session as TD-89, SMS communication between a fixed network terminal (PSTN/ISDN) and a short message service center (W. Goertz, Siemens, Rapporteur). TD-58 is a liaison from SPAN11 to TC AT; it contains the latest version of DTR/SPAN 110062, PSTN Display services, list of information for PSTN use. It contains some amendments made by the rapporteur according to the final version of the TC AT document EN 300 659-3, Subscriber line protocol over the local loop for display (and related) services; Part 3: Data link message and parameter codings. TD-57 is a liaison from SPAN11 on characters set in DTR/SPAN 110062 (EN 300 659-3). Currently, in EN 300 659-3, characters are encoded as specified by ITU-T.50 Recommendation, which specifies only one character set. This may be too limited, since not all languages can be supported. Extension of the number of character sets requires an additional parameter to identify the character set used. SPAN11 will be pleased if TC AT can study the possibility of allowing the encoding of character sets specified by both ITU T.50 Recommendation and ITU T.52 Recommendation; an additional parameter to identify the character set used is needed. TD-91 is a liaison to SPAN11 informing them of the TC AT activities on SMS: AT Features has created a new WI on SMS, within which they will study the opportunity to introduce the ITU-T.52 alphabet. This character set will also be taken into consideration in a new revision of the existing FSK protocol containing SMS capability. W. J. Mellors, WM Services

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ETSI AT MEETING ROSTER, OCTOBER 9 – 13, 2000, S OPHIA ANTIPOLIS, FRANCE Nuno Encarnação, OFCOM Chairman AT Pat O’Keeffe, Eircom Secretary AT Ian Marshall, Nortel Networks (Europe) Chairman ATd Göran Engström, Telia AB Chairman ATf Claire d’Esclercs ETSI Secretariat Ted Laverack ETSI Secretariat Estelle Mancini ETSI Secretariat Belgium ANEC Walter Mellors Belgium Belgacom, S.A. de droit public Marc Bohets Belgium Belgacom, S.A. de droit public Luc Wulgaert Czech Rep. Czech Telecommunication Office Jaroslav Bockstefel Czech Rep. Czech Telecommunication Office Zdenek Gütter Finland Finnet Group Kaj Andersson Finland Telecomms Administration Centre Antero Saarinen France Conexant Systems SAS Wilfrid Dangelo France France Telecom R&D Philippe Lottin France France Telecom R&D Jean Montenot France Natural Microsystems Europe Chris Linford France Natural Microsystems Europe Patrick Meghnagi Germany Cetecom GmbH Joachim Seewald Germany Deutsche Telekom AG Werner Schellhaas Germany Reg TP Christina Gandyra Germany Siemens AG Susanne Frankholz Germany Siemens AG Andreas Kamcke Hungary Ministry of Transport, Communication and Water Management Sandor Szilagyi Ireland Eircom Pat O’Keeffe Italy CSELT - Centro Studi e Laboratori Telecomunicazioni Rodolfo Ceruti Italy Telecom Italia S.p.A. Adriano Depaoli Italy Telecom Italia S.p.A. Roberto Naldi Netherlands KPN Jo Salemans Netherlands KPN Bert Van Leerdam Netherlands Philips Communication Systems Pim B. Hesdahl Norway Norwegian Post and Telecommunications Authority Jan Nergard Norway Norwegian Post and Telecommunications Authority Gunn Anny Roym S Africa Telkom SA Limited Pieter Erasmus Spain Alcatel Espana SA Juan-Antonio Saez Sweden Telefon AB LM Ericsson Per Döfnäs Sweden Telefon AB LM Ericsson Urban Jansson Sweden Telia AB Göran Engström Switzerland OFCOM Nuno Encarnação Switzerland OFCOM Antonio Rullo Switzerland Swisscom Hansueli Gerber UK ADC Microcellular Systems Ltd. Paul Schmokel UK BABT Hilton Carr UK DTI - Department of Trade and Industry John Long UK Mitel Semiconductor Ltd Anthony Morgan UK Mitel Telecom Ltd Edward Hay UK Nortel Networks (Europe) Fred Howett UK Nortel Networks (Europe) Ian Marshall

TR-30.1, MODEMS The TR-30.1 Chair is L. Brown (Motorola). TR-30.1/00-08-065 is the report of the May meeting; TR- 30.1/00-10-080 is the report of the August meeting. V.92, ENHANCEMENTS TO RECOMMENDATION V.90

Draft ITU-T Recommendation V.92, Enhancements to Recommendation V.90, is up for approval at SG16 November 13-17, 2000 in Geneva, Switzerland. Since its Determination in June, considerable testing of product developed to the draft Recommendation has taken place. A number of contributions to the TR-30.1 meeting recommend modifications to the draft text of V.92 resulting from that testing. Some of these were approved as proposed USA contributions to SG16. Those so noted were subsequently approved by the US Study Group D meeting as USA contributions. TR-30.1/00-10-082 (K. Jones, Lucent, Editor) contains proposed changes to the V.92 draft Recommendation resulting from agreements at the August, Huntsville meeting. As a result of other contributions proposing changes to V.92 (discussed below), TR-30.1/00-10-082r3 was approved as a proposed USA contribution to the SG16 meeting. The final version was approved by the TR-30 plenary as TR-30/00-10-056R1. TR-30.1/00-10-083r3 (K. Jones, Lucent, Editor) is the hypothetically revised V.92 draft; it is a version of the draft as it would appear if revisions resulting from agreements at the August meeting are accepted. This is not an approved version of V.92 but one which was used by TR-30.1 for reference purposes. TR-30.1/00-10-085 and 085r1 (V. Krishnan, B. Zhang, Intel) proposes changes to the V.92 draft. During their work to implement V.92, Intel found a number of areas needing clarification. These proposals concentrate on the Fast Parameter Exchange in V.92. TR-30.1/00-10-089 (S. Ólafsson, Conexant Systems; Motorola, Lake Datacomms) addresses problems with V.92 indication in INFO0. At their June meeting in Edinburgh, Scotland, Q13/16 agreed to interchange the role of bits 26 and 27 in the INFO0 sequences transmitted by V.92 modems. It now appears that this change created problems worse than those it intended to solve. TR-30.1/00-10-089 proposes to change the role to where bit 26 of INFO0a and bit 41 of INFO0d indicate V.92 and bit 27 of both indicates a short phase 2. Attempts to correct this problem other than this proposed change were made, but they all had additional problems. TR-30.1/00-10-090 (S. Ólafsson, Conexant Systems) discusses modem roles in V.92. It notes that the scenario of two V.92 analog modems connecting with short phase 1 needs clarification in the V.92 draft. It proposes using phase 2 according to V.34, as originally proposed by Conexant, for that case. In addition, it proposes some text to clarify the role of modems after an on-hold session. These proposals were accepted, and included in TR-30.1/00- 10-083r3. TR-30.1/00-10-091 (M. Nicholas, 3Com) describes implementation issues with the V.92 Quick Connect transition to Phase 2 as defined in the V.92 draft (Edinburgh, June 2000). It proposes a technical change which was expected to alleviate a possible problem; it was not adopted. TR-30.1/00-10-092 (M. Nicholas, 3Com) describes the round trip delay limitations of using V.92 Quick Connect procedures as defined in the V.92 draft, (Edinburgh, June 2000), and proposes a possible solution. TR-30.1/00-10-093 (M. Nicholas, 3Com) describes a problem in detecting the 1st Ja and 1st CPt using training procedures as defined in the V.92 draft; it proposes that the TRN1u signal be differentially encoded to solve this problem. TR-30.1/00-10-094 (M. Nicholas, 3Com) points out that there is a very small inconsistency between the A- law/Mu-law values in V.92 and those in ITU-T Recommendation G.711. It proposes that the -9dBm scl factors and the corresponding -9dBm table be changed to be truly -9dBm, and that 1416 mu-law and 708 A-law be used instead of 1334 mu-law and 667 A-law. As an alternate solution, it asks whether, since it is not the level that matters much for this signal but that it be well-defined, could the text just be changed to read -9.56dBm scale factor and -9.56dBm table. It was felt that this inconsistency is known and that a knowledgeable implementer will understand the significance.

TR-30.1/00-10-095 (M. Nicholas, 3Com) illustrates the problems of using V.92 Quick Connect procedures when network echo cancelers are present. It was recognized that this problem needs attention. An ad hoc group was authorized to propose a solution for distribution within TR-30.1 prior to the October 19 US Study Group D meeting. This was done and a USA contribution was approved for submission to SG16. TR-30.1/00-10-096 (C. Modlin, Texas Instruments) clarifies the definition of the upstream gain, G, in CPd. TR-30.1/00-10-097 (V. Krishnan, B. Zhang, Intel) discusses fast parameter exchange. The V.90 data mode receiver is designed for optimum throughput under V.42 error control. Fast parameter exchange uses data mode modulation, but it uses a less robust error control method. TR-30.1/00-10-097 suggests a few possible solutions, and provides the draft modification for the preferred solution. TR-30.1/00-10-098 (K. Jones, Lucent) proposes quick connect procedure changes. There are some error recovery scenarios in the current quick connect procedures that do not seem to be correctly handled. Also concerns have been raised about the robustness of the current procedures when network echo devices are present. TR-30.1/00-10-098 proposes minor modifications to address these concerns. TR-30.1/00-10-101 (K. Chu, Conexant Systems) contains a series of diagrams depicting typical V.92 modem- on-hold scenarios. It proposes that they be considered for inclusion as an appendix to V.92. This contribution was approved as a proposed USA contribution to SG16. TR-30.1/00-10-102 (M. Nicholas, 3Com) notes that interoperability testing has shown there is some confusion over the definition of the constellation gain, G, as defined in V.92. This problem is similar to the problem pointed out in TR-30.1/00-10-096. It has also revealed a limitation with the current V.92 constellation. TR- 30.1/00-10-102 proposes that the client modem send LTRN1u value in INFO1a as was previously suggested. This will allow the digital modem to calculate the channel loss. This will also allow the client modem to determine the numbering system it desires to use. V.44, DATA COMPRESSION PROCEDURES

As with draft Recommendation V.92, it was found that draft Recommendation V.44, Data compression procedures, also required additional corrections. TR-30.1/00-10-086 (J. Heath, Hughes Network Systems) is a proposed USA contribution to the November SG16 meeting. It proposes a few substantive changes to Annex B, Operation in packet networks, and several editorial changes, to the Determined draft of Recommendation V.44 (TD-12R1, June Q8/16 meeting). TR-30.1/00-10-087 (J. Heath, Hughes Network Systems) is also a proposed USA contribution to SG16. It proposes that parameter identifiers x’40’ through x’5F’ in the user data sub-field of the XID information field be reserved for V.44 and future data compression XID negotiation parameters. It further proposes the creation of a register to track and assign additional data compression parameter identifiers within the user data sub-field. The proposals for changes to V.44 contained in TR-30.1/00-10-086 and TR-30.1/00-10-087 were combined into a single proposed USA contribution, which was approved at the TR-30 plenary session as TR-30/00-10- 053R1. The proposal for establishment of a registry for data compression parameters was included in a new proposed USA contribution, which was approved at the TR-30 plenary as TR-30/00-10-054R1. TR-30.1/00-10-088 (J. Heath, Hughes Network Systems; Lucent) provides information and clarification of FLUSH procedures in V.44. The V.44 source code that Hughes provided to several manufacturers does not match the FLUSH procedures in the Determined version of Recommendation of V.44 in a particular instance. This contribution intends to make all companies aware that the procedures for the FLUSH are correct as defined in Recommendation V.44 and that the source code did not follow the defined procedure in a specific instance. Table 5/V.44 specifically states that an ordinal output immediately following a control code shall have a code prefix of ‘0’. This is correct. The V.44 source code provided several months ago does not conform to Table 5/V.44 in one instance. An ordinal output immediately following a FLUSH control code may, in some instances, have a code prefix of ‘00’. This is NOT correct. New source code, with minor fixes to the V.44 encoder and decoder, to correct this non-conformity has been provided to affected companies and is available if desired.

TR-30.1/00-10-099 (K. Lacey, U.S. Robotics) addresses a problem with V.44 negotiation in the user field of V.42. It is a secondary submission and clarification of TR-30.1/00-08-075 (K. Lacey, C. Wallach, US Robotics) from the August, Huntsville meeting. The new V.44 compression standard is negotiated by using the user sub-field of the V.42 XID frame. This utilization causes compatibility problems for companies that have already used the user sub-field. TR-30.1/00-10-099 proposes a solution to allow an alternate mechanism for negotiating enhanced error control and data compression procedures. This problem was also discussed in TR- 30.1/00-10-087. TR-30.1/00-10-100 (K. Lacey, U.S. Robotics) proposes an editorial correction to V.44. The wording of draft V.44 refers to “transmit direction and receive direction.” This can be confusing, particularly with a full-duplex link. TR-30.1/00-10-100 proposes replacing all instances of the phrase “transmit direction” with “negotiation initiator-responder direction,” and all instances of the phrase “receive direction” with “negotiation responder-initiator direction” in Section 7.4, Table 10, and Table A1. This was not accepted. Since consensus could not be reached on a number of the suggested items raised, companies were encouraged to bring company contributions to the US Study Group D meeting for the SG16 meeting in November. OTHER HIGHLIGHTS

TR-30.1/00-10-103 (L. Brown, Motorola) contains a document presented to the August Q13/16 Rapporteurs meeting. It defines the procedures to be applied to allow data transmission between terminals where, in addition to the PSTN or ISDN, a portion of the transmission path between terminals includes an IP network, e.g., the Internet. It was provided by the TR-30.1 Chair for information. It will be discussed under Question 23 during the November meeting of SG16. TR-30.1/00-10-084 (V. Krishnan, Intel) is a copy of the draft of PN-2330, Procedures for automatic interworking between automode modems and V.32bis, V.32, V.22bis, V.22, V.21, V.23, 212-type, and 103-type modems, from April 1991. This work had begun some years ago as a formal standard to replace Interim Standard IS- 63, which was recently withdrawn. TR-30.1 never completed work on PN-2330, having spent the time instead on the V.90 series of modem standards. TR-30.1 considered the issue of completing this work. The project number has long expired; application of a new one would be necessary to continue. TR-30.1 decided to open a new project and to proceed with the development of this standard. Fred Lucas, 3Com

TR-30.2, DATA TRANSMISSION The TR-30.2 Chair is F. Lucas (3Com). TR-30.2/00-10-028 is the report of the August meeting. The focus of this TR-30.2 meeting was to prepare contributions for the SG16 meeting Nov. 13-17, which would go through the USA approval process at Study Group D on October 19. PN-4647, ADDENDUM 1 TO TIA/EIA-678

The Chair reported that the Addendum to TIA/EIA-678, Data transmission systems and equipment - Serial asynchronous automatic dialing and control for character mode DCE on wireless data services, had been sent to TIA for final approval and publication. This Addendum should be available for purchase within the next couple of months. PN-4584, TIA/EIA-644 R EVISION

The Chair reported that the SP-4584 ballot closed on August 7; there were no negative ballots. One ballot with comments was received (TR-30.2/00-10-031) from F. Stein, TIA editorial consultant, with editorial comments. TR-30.2 reviewed the comments, and they were accepted. The Editor, J. Goldie (National Semiconductor), will make the revisions, and the revised version will be sent to TIA for approval and publication. PN-4828, ELECTRICAL CHARACTERISTIC OF M-LVDS

The TR-30.2.1 ad hoc committee, under the chair of J. Goldie (National Semiconductor), did not meet. J. Goldie had indicated that the group still expects to bring the draft of PN-4828, Electrical characteristics of multipoint low voltage differential signaling (M-LVDS) interface, to the TR-30.2 December meeting for approval for industry ballot.

PN-4686, REVISION OF TIA/EIA-602

The Chair reported that the revision of TIA/EIA-602, Data transmission systems and equipment - Serial asynchronous automatic dialing and control, has been published by TIA and is available for purchase. ADDITIONS/MODIFICATIONS TO V.25X COMMANDS

The primary work of this TR-30.2 meeting was consideration of commands to be added to the V.250 Implementers Guide, which is being written under Question 7 in Study Group 16. Three proposed USA contributions were approved at the meeting, and were then approved by the U.S. Study Group D committee as USA contributions on October 19. V.92 Commands for V.250 Implementer’s Guide TR-30.2/00-10-029 (F. Lucas, 3Com) is the draft of a proposed USA contribution to the November SG16 meeting. It is proposed text for the new +P series of commands created to support PCM DCE to be included in the V.250 Implementers Guide. It represents the agreements reached at the August TR-30.2 meeting in Huntsville, Canada, and includes additional editorial “clean up.” TR-30.2/00-10-032 (K. Chu, Conexant Systems) proposes a modification to the +PMHR (initiate modem on hold) command as described in TR-30.2/00-10-029. TR-30.2/00-10-032 proposes changes to support a more interactive user procedure when the MOH request is granted with a timeout by the remote DTE. TR-30.2 considered these two contributions and agreed on a number of revisions to TR-30.1/00-10-029. F. Lucas made the changes and TR-30.2/00-10-029R1 was approved to go to TR-30 as a proposed USA contribution. It is expected that this document will be accepted at the at the SG16 meeting and will be incorporated into the V.250 Implementers Guide. V.44 Commands for V.250 Implementer’s Guide The Chair reported that an open item remained from the August meeting that needed resolution. TR-30.2/00-08- 026 (K. Chu, Conexant) provided comments on Draft 2 of the V.250 Implementers Guide. It suggested that the +DCS command was redundant; the same result is achieved by using +DS=0 and +DS44=0. TR-30.2 considered this, and agreed with it. K. Chu drafted a proposal to delete the +DCS command (TR-30.2/00-10-033), as a proposed USA contribution to SG16; it was approved. There is a possibility that it will be discussed at SG16, but it is expected to be adopted in the end. V.59 Commands for V.250 Implementer’s Guide TR-30.2 reviewed a contribution (TR-30.2/00-08-027, B. Adams, Signals & Software) from the August 2000 meeting which suggested a +TMO command to support V.59. The Chair provided a draft wording (TR-30.2/00- 10-030) as a proposed USA contribution to SG16. TR-30.2 reviewed it, and agreed to a number of revisions; the final version, TR-30.2/00-10-030R2, was approved. Fred Lucas, 3Com

TR-30.3, DATA COMMUNICATIONS EQUIPMENT EVALUATION AND NETWORK INTERFACES TR-30.3/00-10-063, Report of Meeting 108 at Deerhurst, Huntsville, Ont, Canada was accepted with minor changes. TR-30.3/00-10-064 is the Assignment List from August TR-30.3 Meeting. TR-30.3/00-10-065 is the October 2000 Document Register. TR-30.3/00-08-058R1 is a letter thanking J-P. Houdard (TI) for his contributions to TR-30 and TR-30.3. It was signed by F. Lucas (3Com, Chair TR-30) and J. Douglass (Conexant, Chair TR-30.3). LIAISON REPORTS

TR-30.3/00-10-071 (L. Brown, Motorola) is a proposed USA contribution to SG16/Q10 on the status of TIA/EIA-793, North American Telephone Network Transmission Model for Evaluating Analog Client and Digitally Connected Server Modems. It notes that TIA/EIA-793 is now published and is therefore available for consideration to be included in an ITU Recommendation. TR-30.3 approved this document. It was reported that SG16 Working Party 1 Q4, Q10 and Q23 will be combined into one question for the new Study Period. It was also reported that Modem “AT” commands are now documented in V.250.

T1E1 Spectrum Management document, LB 869 (third public review) is expected to go out for ballot, pass, and become T1.417. J. Douglass (Conexant) reported that new domestic and international network statistics are expected to be received from an anonymous source. The international network statistics will be submitted to the ITU when they are available. PN-3509, REVISION OF TSB-38 (T EST PROCEDURES FOR EVALUATING MODEM PERFORMANCE)

TR-30.3/00-08-062 is Draft 13 of PN-3509, Test procedure for Evaluation of PCM Modems (G. Bretting, Compaq, Editor). TR-30.3 focused on V.92 Quick Connect and Modem on Hold (MOH) testing, and worked on the following sections: • 5.3.5 V.92 Connect time testing (fixed location) • 5.3.6 V.92 Connect time testing (mobile location) • 5.3.7 Modem on Hold • 5.3.8 Connect Time vs. Network Model These V.92 tests will be included in PN-3509 Draft 14. J. Douglass (Conexant) and W. Henderson (Henderson Labs) will request that someone from TR-30.1 discuss Modem-On-Hold and Call-Waiting at the December TR-30.3 meeting, because TR-30.3 needs to map all possible event handling events. W. Henderson will draft a liaison letter to TR-30.2 requesting a feature that permits clearing of modem train-up file for quick connect. W. Henderson will provide modem test results for V.44 test files, as well as an updated report and files for distribution. He will contact A. Clark (consultant) about a program to analyze files for V.44 testing. T. McGrath (TAS) will request that TAS put a priority on being able to run large files for V.44 testing. PN-3857, NORTH AMERICAN TELEPHONE NETWORK TRANSMISSION MODEL FOR EVALUATING ANALOG CLIENT AND DIGITALLY CONNECTED SERVER MODEMS

TR-30.3/00-10-066 (TIA) is a summary of the PN-3857 ballot responses. There were seven approvals and one abstention. Three ballots were not returned. TR-30.3/00-10-068 (B. Zidek-Connor, TIA) is the cover letter, informing TR-30.3 that the ballot was approved and is now ready for TSSC approval prior to publication. TR-30.3/00-10-067 (P. Dillon, Marconi) provides 11 clean-up comments on PN-3857 – Draft 14, dated March 2000. W. Henderson (Henderson Labs) will draft a response to P. Dillon. TR-30.3 decided to include many of the recommendations in the next revision of TIA/EIA-793. TR-30.3/00-10-069 (M. Pellegrini, TAS) is e-mail concerning the status of TAS adding features to test equipment. After discussion, TAS agreed to put a priority on modifying the simulator equipment so that it can run V.90 tests (larger files, Caller ID/Call waiting, MOH, upstream PCM, distributed loop noise), although resources are not expected to be available for 3 to 6 months. TR-30.3/00-10-070 (P. Dillon, Marconi) is e-mail concerning adding a supplement to T1.403.2 (DS1 - Robbed- Bit Signaling State Definitions) to define Bit Stuffing for Robbed Bit Signaling. P. Dillon notes that it will be completed in time for the T1E1.2 meeting on November 15. E. Schulz (Lucent) will be editor for the international version of PN-3857 (V.test). G. Bretting (Compaq) will provide setup information and test results for TR-30.3/00-03-034 (V.test draft 1). J. Douglass (TR-30.3 Chair, Conexant) will open a new project to revise TIA/EIA-793, North American Telephone Network Transmission Model for Evaluating Analog Client and Digitally Connected Server Modems. PN-4254, NETWORK ACCESS TRANSMISSION MODEL FOR EVALUATING XDSL MODEM PERFORMANCE

TR-30.3/00-10-801R4 is PN-4254, Draft 12, Network Access Transmission Model for Evaluating xDSL Modem Performance, Volume 1: Network Model (same as T1E1.4/00-801R4). TR-30.3/00-08-855R1 is a revised TR-30.3 liaison letter to K. Harris (Nortel) concerning the effect of AM radio ingress on xDSL. It requests that K. Harris review her data, and, if possible, provide TR-30.3 with the distribution

of AM radio signals and their transmitted power over the entire band. In particular, TR-30.3 is interested in characterizing these distributions in Tier 1 and Tier 2 cities. TR-30.3/00-09-857R2, xDSL Network Simulator Block Diagram (R. Cassan, DLS Test Works), was assigned at the August meeting, and presented first at the September ad hoc meeting. It includes a detailed test configuration diagram. TR-30.3/00-10-800R4 (RK Smith and P. Kyees, Paradyne) is the updated Issues List for xDSL Transmission Model Project. TR-30.3/00-09-858AH, PN-4254: Rational for Model Structure and Proposed IC Table Templates (RK Smith, Paradyne), proposes that the network access model be formally described in terms of three constituent elements: Physical Description, Statistical Impairments Model and Specified Impairments Model. TR-30.3/00-08-858 are draft IC/Loop Tables for PN-4254, created at the August TR-30.3 meeting. TR-30.3/00-09-859AHr2, PN-4254: Proposed Impairment Combination Table (P. Kyees, Paradyne), fills in the IC table templates. Data is provided for both the Residential and the Multi-user/Business Network Impairment Combination Tables. TR-30.3/00-09-860AH (P. Kyees, Paradyne) provides a proposed Impairment Model for Section 5.1 (Definition of Impairments). The following, all from RK Smith (Paradyne) were created during the September TR-30.3 Ad Hoc meeting: TR-30.3/00-10-862AH, a hand-drawn block diagram of CO TR-30.3/00-09-863AH, Steady State Impairment Combination Table TR-30.3/00-09-864AH, Revised Impairment Combination Tables TR-30.3/00-09-865AH, Simulator Implementation Model TR-30.3/00-09-866AH, CO Configuration for Line Sharing and Non-Line Sharing TR-30.3/00-10-867AH, Network Access Impairment Model TR-30.3/00-10-868, Readjusted xDSL Scores for Network Access Transmission Model (R. Perez, Telcordia), provides redistributed test loop scores; it had been suggested that the loops outside of the CSA design rules would decrease by 25% by the year 2002. R. Perez (Telcordia) will update TR-30.3/00-10-868 to: • Remove loops 1 and 6. • Modify loop 8, 10 and 11 to give more distributed resistance. • Add granularity to loops about 9k (12k, 15k, 18k). TR-30.3/00-10-869, Simulator Subsection Model, was created during the TR-30.3 meeting. Discussion resulted in the following comments, decisions and assignments: J. Douglass will ask J. Moran and DLS Test Works to calculate the loop characteristics. P. Kyees (Paradyne) will also look into calculating loop characteristics. DLS Test Works will provide R. Perez (Telcordia) with enough reference to do loop calculations. R. Perez (Telcordia) will calculate loop characteristics base on these references. RK Smith (Paradyne) and P. Kyees (Paradyne) will determine if resources are available for spot checks to validate the network model using real loop plant and using a spectrum analyzer to measure the crosstalk transfer function. TR-30.3/00-10-861AH (G. Young, Chair DSL Forum) is a liaison reply from the DSL Forum. They note that it is not obvious why TR-30.3 proposes using several line simulators and noise sources. Although this simulates reality closely, it would mean extra complexity in implementing the tests and add test uncertainties. The DSL Forum would like further information on how the loop simulators relate to each other. TR-30.3 believes that the DSL network model can be simplified as requested by the DSL Forum: 1. The Simulator Implementation Model in TR-30.3/00-10-867AH (Network Access Impairment Model) shows composite CO and CPE interferers. The composite interferers are made up of the interferers from different injection points. The composite interferer characteristics can be obtained by multiplying interferer at each injection point by the transfer function for the associated sections. 2. Composite of transfer functions ‘a’ and ‘b’ [Xƒ(a) + Xƒ(b)] will be inserted at the DUT (Device Under Test). 3. The interferer transfer function is not the same as the “active loop under test” transfer function. 4. Transfer function ‘a’ Xƒ(a) = loop under test 5. Transfer function ‘b’ Xƒ(b) = cross-talk, Multiply the spectrum by the Xƒ(b)

6. It is believed that Xƒ(a) is a function that decreases in value with increasing signal frequency. 7. It is believed that Xƒ(b) is a function that increases in value with increasing signal frequency. 8. TR-30.3 believes that it is accurate to multiply the intermediate crosstalk point by the transfer function, but TR- 30.3 needs to fully define the intermediate characteristics. J. Douglass (Conexant) will send a response to the DSL Forum. TR-30.3 needs to determine the signal effects where there are bridge-taps near the DUT (device under test) and the effect of (or on) crosstalk noise. They also need to determine if the referenced bridge-taps nullify or amplify crosstalk noise. P. Kyees (Paradyne) and M. Ayoub (Conexant) will create a section for Annex E concerning sources of CO crosstalk. It is expected that the Y factor can be removed from the Impairment Combination Table. R. Perez (Telcordia) ran a cable circuit analyses program to compare results with J-P. Houdard’s (TI) calculations. The results didn’t match. The following are action items: • An Annex for explaining the Simplified Simulator Block Diagram needs to be added. • An Impairment Condition/Combination Matrix Table needs to be created. • W. Henderson (Henderson Labs) will define Transient Impairments. • W. Henderson (Henderson Labs) will define Intermodulation characteristics for phones. • RK Smith (Paradyne) will define signal level conditions for phones. • P. Kyees (Paradyne) will define POTS interference characteristics. At the December meeting, TR-30.3 expects to release PN-4254 to T1E1 for comment, to DSL Forum for comment, to ITU SG15/Q4 for comment, and to TIA for TR-30.3 Committee Letter Ballot (Green). J. Douglass (Conexant) will present PN-4254 at the January 2001 Q4/15 meeting in Florida. PN-4255, TEST PROCEDURES FOR EVALUATING XDSL SYSTEM PERFORMANCE

A Profile Table for Steady State, Transient, and Home Wiring impairments was created for Rural, Residential and Multiple Unit/Business. A Profile Table for Non-Splittered, Splittered and Distributed Splitter was created for Steady State, Transient and Impairment Combinations. There are 864 test conditions per category: 864 = (12 loops) x (2 connection types) x (4 severity levels) x (3 home wiring models) x 3 specified impairment levels) Example test reduction method for a Single Family Home (goal is to complete test in 1 day) is to reduce severity level from 4 to 2: 432 = (12 loops) x (2 CT) x (2 severity levels) x (3 HW) x (Specified Impairments) Tests planned include: 1. Training time -- Measure time & consistency 2. Connect Rate -- Measure carrier rate & consistency 3. Corrected errors: (a) Bit Error Rate -- Count & consistency (b) Packet Error Rate -- Count & consistency (c) Cell Error Rate -- Count & consistency 4. Uncorrected errors: (a) Bit Error Rate -- Count & consistency (b) Packet Error Rate -- Count & consistency (c) Cell Error Rate -- Count & consistency 5. Robustness: (a) Retraining -- Count (b) Connect reliability -- Carrier rate & consistency 6. Throughput: (a) Streaming (Raw) Data (b) FTP 7. Latency: (a) Block delay -- Measure time & consistency (b) Ping delay -- Measure time & consistency

(c) Protocol Negotiation -- Measure time & consistency Test categories include: • Tests #1 & 2 -- Start-up • Tests #3 & 4 -- Error rate • Test #5 -- Transient tests/stress • Tests #6 & 7 -- System tests Test output looks like: • Test #1 = NMC-SS vs. Connect Speed (data rate) • Test #1 = NMC-SS vs. training time • Test #1 = NMC-SS vs. training time consistency • Test #2 = NMC-SS vs. Connect Reliability (consistency) • Tests #3 & 4 = NMC-SS vs. Error Rate • Test #5 (transients) = 1 loop (mid-range of easy loops) & 2 loops (in range of difficult) • Test #6 = Throughput vs. NMC-SS Stress tests include: • Incoming calls (a) Answer – Signal level change, 2-4 ring answer, multiple phones going off/on-hook • No answer – multiple times, 6 rings, wait 2 minutes, 6 rings • Call disconnect – Loop current drop out, Signal level changes • Outgoing calls • DTMF (a) Pulse-dial • Other (a) Light Dimmer (b) Motor (c) Binder cable impulse W. Henderson (Henderson Lab) will create a new draft of PN-4255 incorporating the tests defined by TR-30.3. Jack Douglass, Conexant

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Communications Standards Summary (ISSN 1075-5721), a quarterly publication reporting on all active projects and recently completed standards of the TIA’s (Telecommunications Industry Association’s) TR- committees. Authorized by TIA. For more details visit http://www.csrstds.com. To receive a complimentary issue of either of CSR’s technical journals, please contact Elaine Baskin, tel +1 650 856-9018, fax +1 650 856-6591, e-mail: [email protected]

TR-30 MEETING ROSTER, OCTOBER 9 – 13, 2000, COLUMBIA, MD

Fred Lucas, 3Com TR-30 Chair Les Brown, Motorola TR-30.1 Chair Fred Lucas, 3Com TR-30.2 Chair Jack Douglass, Conexant TR-30.3 Chair Host: 3Com

3Com Fred Lucas 3Com Michael Nicholas 3Com Timdor Sakharuk ADI Haim Primo Broadcom Art Carlson Cisco Systems Tom Martin Cisco Systems Alex Urguizo Compaq Computer Greg Bretting Conexant Micha Anholt Conexant Mounir Ayoub Conexant Burk Beadle Conexant Keith Chu Conexant Jack Douglass Conexant Sverrir Olafsson Conexant Charles Raasch ESS Ping Dong ESS Hong Yao Henderson Comm. Labs Warren Henderson Hughes Network Systems Jeff Heath Infineon Neal King Intel Vedavalli Krishnan Intel Bo Zhang Lucent Technologies Horace Hagen Lucent Technologies Mark Hargrove Lucent Technologies Ken Jones Lucent Technologies John Magill Lucent Technologies Ed Schulz Lucent Technologies Jay Yu Motorola Les Brown Motorola Patrick Maurer Paradyne Philip Kyees Paradyne R K Smith Patton Electronics Azmi Al-Kurd PCTel Yuri Goldstein PCTel David Tung Soltel Gerald Hoefer Spirent Comm. (TAS) Thomas McGrath Telcordia Ricardo Perez Telewise Comm. Greg Yang TI Cory Modlin TI Piyush Patel TI Adrian Ziakrzewski TIA Susan Hoyler TIA Billie Zydek-Conner US Robotics Kevin Lacey

40 Vol. 11.10 Copyright © CSR 2000 November 2000 COMMUNICATIONS STANDARDS REVIEW REPORT OF Q4/15, XDSL NETWORK ACCESS TRANSCEIVERS, RAPPORTEURS MEETING, OCTOBER 23 – 27, 2000, BANGALORE (GOA), INDIA The scope of Q4/15 is the development of Recommendations related to digital subscriber line (DSL). R. Stuart (3Com) is the Q4/15 Rapporteur. BI-000 is the document list. BI-001 is the agenda. BI-002 is the report of the April, 2000 Rapporteurs meeting in Huntsville, Canada. BI-004 provides the Q4/15 Rapporteur meeting electronic document submission guidelines. BI-005 is the attendance roster of this meeting. While the documents maintain the Bangalore, India designation (BI), the meeting actually took place in Goa as there was some question about unrest in the Bangalore area. Concerns were noted during and after the meeting about the number and length of the ad hoc meetings as several spanned two days. In effect, the ad hocs became unplanned (not on the prepublished agenda) parallel sessions that prevented some from participating in all the discussions they desired. BI-033 (S. Palm, Broadcom) is the draft G.989.1 IPR statement. Broadcom has submitted a Patent statement regarding draft G.989.1 to the TSB with Patent Policy Option 2 (paragraph 2.2) checked off. The statement has been recorded by the TSB as ID G989_1-01. The database of statements is available at: . BI-070 (Y. Kumar, Catena) is the draft G.dmt.bis/G.lite.bis IPR statement. Catena Networks has submitted a patent statement regarding draft Recommendations G.dmt.bis and G.lite.bis to the TSB with Option 2 checked off. The wording for this is as follows: “The Patent Holder is prepared to grant, on the basis of reciprocity for the above ITU-T Recommendation/ISO/IEC International Standard, a license to an unrestricted number of applicants on a worldwide, non-discriminatory basis and on reasonable terms and conditions to manufacture, use, and/or sell implementations of the above ITU-T Recommendation/ISO/IEC International Standard. Such negotiations are left to the parties concerned and are performed outside the ITU-T/ISO/IEC.” G.GEN BI-023 is a liaison from the DSL Forum. While DSL is being well received by the user community and future projections are excellent, a significant population of users cannot receive DSL service because they are served by a DLC (digital loop carrier) system, a pedestal, or are beyond 17K feet from a Central Office. The DSL Forum believes a significant amount of the total available market cannot be served by DSL because of the limitations to the existing implementations. DSL deployment must exist without regard to subscriber location or economic status. Too many subscribers are currently out of reach of DSL because of distance from the Central Office or due to the fact they are not served directly by copper from the Central Office. The DSL Forum invites the ITU-T to assist in determining how Phy (Physical Layer) standards can be improved to address this situation. The critical goal to be met is that of being able to provide broadband data delivery via DSL everywhere, to every subscriber without regard to the customer’s location. The DSL Forum requests information on the ITU-T’s plans to implement the required Phy standards to meet this goal. Specifically, the DSL Forum sees an urgent need to improve DSL loop reach in the presence of impairments (e.g., crosstalk, RFI, bridged taps), and reduce DSL transceiver power consumption to facilitate RAM and DLC implementation. DSL Forum held a BOF at its August-September meeting in Dublin to address this issue; a number of possible solutions were proposed, including: • NGDLC • Remote DSLAM • Remote Access Multiplexer (RAM) in the RT • DLC line cards • Improved ADSL Modulation recommendations • All digital ADSL recommendations • ADSL which provides improvements in canceling noise and removing tap impairments • Improved loop qualification recommendations • Mid-span repeaters recommendations for ADSL • Loop extender recommendations for ADSL See also CSR Vol.11.9, DSL Forum Operations and Network Management WG report.

BI-dslf is the response from Q4/15 to BI-023. Q4/15 points out that Recommendation G.shdsl can be deployed using repeaters and/or 2-pair configuration to extend loop reach pursuant to nation spectral compatibility standards. Regarding current generation ADSL, Recommendations G.992.1 and G.992.2 can be deployed in DLC environments with proper loop management, i.e., with a wire center with no feed-through loops. Regarding next generation ADSL Recommendations, Q4/15 is currently investigating new modulation and coding features that will extend loop reach. Additionally, in the next generation ADSL Recommendations, Q4/15 has agreed to include functionality to support deployment in a mid-span DLC environment; there is also a call for papers for ADSL loop extenders. BI-034 (F. Van der Putten, Alcatel, Editor, G.dmt.bis) provides the proposed new PMD section for the current draft of the G.dmt.bis Recommendation. This is an editor’s contribution and is consistent with current agreements in the issues list. The intent is to use this text in the G.lite.bis and G.dmt.bis documents by reference. The editor proposes to adopt this as working text for the G.dmt.bis recommendation. The following four contributions from the G.lite.bis Editor (T. Cole, AMD) provide various proposed sections for the current draft of the G.lite.bis Recommendation. They are consistent with current agreements in the issues list. The intent is to include the proposed texts in the G.lite.bis and G.dmt.bis documents by reference. The editor proposes that they be adopted as working text in the respective currently blank sections of G.lite.bis: • BI-035 - proposed ATM-TC section • BI-036 - proposed STM-TC section • BI-037 - proposed new framing section • BI-038 - proposed description of the management entity RFI BI-031 is a liaison from ETSI TM6 providing information on EMC standardization activities in response to the questions on RFI egress raised by Q4/15 in HC-085 (R. Stuart, 3Com, Q4/15 Rapporteur, see CSR Vol. 11.8). • ETSI TC ERM WG EMC, chaired by R. Storrs, has the responsibility to determine EMC limits for non-radio systems. They produce EN 300 386, which contains relevant limits and will soon include the changes proposed to CISPR22 (and to EN 55022). • ETSI/CENELEC is a joint working group on EMC, of conducted transmission networks also chaired by R. Storrs. This group has been created recently, with the scope to “formulate immunity and emission requirements based on a common approach for CATV, powerline and telecommunication networks.” • CENELEC TC209, TC 215, SC205A and TC210 are also involved in the elaboration of EMC related standards. BI-032 is a liaison from TM6 to Q4/15 regarding RFI ingress on access lines carrying xDSL signals; it advises Q4/15 of the outcome of a discussion on RFI ingress test conditions for SDSL and ADSL, at frequencies up to about ~1MHz. TM6 has decided to address the RFI ingress problem space by breaking the work down in the following parts: • Frequency and power (dBm) levels for differential mode ingress in the band to ~1MHz • Application of modulation to the ingress test signals • Test method(s) for RFI ingress testing of xDSL TM6 supports the ingress power levels in TD-35 (D. Daecke, Infineon; CSR Vol. 11.9, TM6 report): 333kHz, -90dBm and 387kHz, -85dBm. There is a general lowering of ingress levels in the band between LW and MW broadcast frequencies across Europe; this has been confirmed by the 3,000 noise measurements made by BT. TM6 reaffirmed the currently agreed set of test frequencies, as used in G.test for Europe and repeated in TD-35. TM6 emphasizes that RFI ingress levels and test methodology should be repeatable and realistic. Levels that are too high may have cost/complexity implications for xDSL transceiver designs. If xDSL systems are susceptible to RFI ingress, it will be very costly for the telco to “roll a truck” and either fit mitigation devices, e.g., common mode chokes, or replace access cabling. A telco can expect to be required to perform some limited retrospective re- engineering of the access network, but the percentage of occurrence must be kept to an absolute minimum. Specification of common mode levels for RFI ingress will be also required; this will enable operators to make assessments if their frequency dependent cable balance is significantly different from the baseline balance characteristic. Relevant study points in the SDSL and ADSL projects exist within TM6 for doing further work on RFI ingress levels; TM6 intends to supply more substantive information after its next meeting (November – December, 2000).

BI-044 (R. Stolle, Infineon) is a tutorial contribution on the electromagnetic coupling theory of twisted pair cables. This contribution also supplies approximation formulae for the prediction of RFI egress and ingress. BI-045 (D. Daecke, Infineon) gives background information on the discussions held by TM6, in their September meeting in Vienna, on tone levels in RFI ingress noise tests and RFI ingress test methods. At that meeting, TM6 took into account the new information given in TD-35 through TD-39, which critically analyzed the RFI tests that had previously been agreed for ADSL and proposed for SDSL. It was shown that the scenario modeled in these tests is impossible and cannot occur; as an alternative, TD-35, RFI ingress tests for SDSL, was proposed as a worst-case test. The ADSL and SDSL study points on RFI ingress tests that had the status “agreed” were moved back to the status “under study.” BI-045 includes text from ETSI contributions TD-35, TD-36, The electromagnetic field environment in Europe, and TD-37, Frequency dependence of cable balance. BI-078 (D. Daecke, Infineon; Siemens) notes that closure of the work on RFI ingress levels is scheduled for the next TM6 meeting in November. To avoid differences between the European requirements in ITU-T standards and ETSI standards, BI-078 proposes: • G.dmt.bis: Move the agreement on the RFI ingress tests from BA-059 (CSR Vol. 11.7) back to “open.” • G.dmt.bis: Adopt the new European RFI ingress tests for G.dmt.bis as soon as they are available. • G.shdsl: Remove the old European RFI ingress test from the G.991.2 (ex G.shdsl) draft Recommendation (HC- R15r3©, Paragraph B.3.5.3.5; CSR Vol. 11.8). • G.shdsl: Adopt the new European RFI ingress tests for G.shdsl as soon as they are available. These issues remain open. BI-084 (L. Humphrey, Nortel) reports the result of calculations to establish the near field magnetic component at 1m from various lengths of overhead drop wire. Unbalance is assumed to arise in the distribution cable and is represented as a point source of common mode signal. BI-084r1 corrects the Y axis label in figure 4 - changing m to mu. An ad hoc chaired by L. Humphrey prepared a draft liaison (BI-115) to the ITU SG rapporteur responsible for the lightening protection Recommendation K.36. INITIALIZATION

BI-091 (K. Harris, Nortel) proposes a new initialization sequence for G.lite.bis and G.gen.bis that is suitable for fast retrain and full initialization without the use of profiles. This proposal enables termination, at the vendor’s discretion, of signals that some modems may require for significant time periods. BI-096 (B. Barazesh, R. Banerjea, Lucent) proposes a simplified initialization procedure for G.lite.bis and G.dmt.bis. It will allow each ATU-C and ATU-R receiver to autonomously determine its receive rate and parameters, taking into account the requirements provided by ATU-C such as maximum rate, margin, and latency. The proposed method reduces initialization time up to 1.2 seconds; this time can be used to send other useful information. BI-099 (M. Jong-Hyuck Park, Samsung AIT) proposes the basic structure of adaptive length initialization sequence for G.dmt.bis and G.lite.bis. The proposed structure provides methods to be used for defining variable length training and message sequences. By utilizing this structure, the issues raised for the adaptive length initialization can be solved. This contribution applies to G.dmt.bis and G.lite.bis. BI-100 (M. Arvind, A. Verma, Silicon Automation Systems) lists the requirements of an initialization procedure for G.lite.bis and G.dmt.bis. BI-101 (M. Arvind, A. Verma, Silicon Automation Systems) provides modifications to the G.lite.bis and G.dmt.bis initialization proposal (Section 0.4 of BI-R17r1, draft Recommendation G.dmt.bis). The modifications intend to make the training robust and reduce its duration. Since training sequence lengths are variable, the same procedure may used for shortened initialization. BI-111 (T. Cole [AMD], F. Van der Putten [Alcatel], ad hoc Conveners) is the report of the ad hoc on initialization. The meeting addressed the G.dmt.bis and G.lite.bis contributions BI-091, 096, 099, 100, 101, and G.lite contribution BI-097. The goal of the meeting was to come up with requirements for the initialization (G.hs, training, analysis, exchange). The ad hoc agreed that the following points shall be requirements for the initialization:

G.hs initialization requirements: • The adaptive length initialization sequence may or may not include the use of profiles. • The performance shall be maximized through direct selection of the coding parameters by the receiver with general boundaries set by the CO. • Before sufficient power cutback is applied, the signals shall be carefully constructed to limit intermodulation products and distortions in the voice band. • The transmit power at which G.hs messages are sent shall be indicated within a G.hs message. • The parameters to be exchanged in G.hs shall be carefully selected to limit the duration of the G.hs session. Other parameters which are only needed prior to exchange shall be sent after G.hs. A mechanism shall be provided in the post-handshake sequence for that purpose. Training initialization requirements: • The ATU-R shall be able to determine cutback levels based on a vendor discretionary line probe signal. • The ATU-R shall be able to communicate the cutback levels to the ATU-C using a rapid and reliable signaling mechanism. • The ATU-x shall be able to exchange the optional capabilities and boundary requirements for maximum and initial configuration parameters using a robust signaling mechanism. Analysis and Exchange initialization requirements: • No requirements were agreed. It was discussed with interest but without conclusion that: • The end of the PMD training might not be the end of activation. The ad hoc discussed the concept of layering, i.e., the PMD layer is trained, then the PMS layer is activated. • In the shortening of the activation sequence, shortening could include that G.hs is not redone and entry points are provided later in the activation sequence. FRAMING

BI-047 (S. Abbas, Centillium) provides information on potential efficient, multi-latency, framing options to support simultaneous transport of channelized voice and data over second-generation ADSL modems (bis versions). There are number of desirable features that form the requirements for the framing in the second-generation ADSL modems. The notables are lossless rate change and repartitioning, highest framing efficiency, minimum guaranteed overhead bandwidth and its programmability, maximum coding gain, and support of multiple latency paths for applications such as channelized voice. A framer that satisfies all these requirements simultaneously may be considered as an optimum framer. This contribution aims to describe some of these optimum options, with the intent to stimulate discussion on this subject. BI-048 (ADC Telecommunications, Aware, Cisco Systems, Ikanos, Legerity, Siemens ICN, SigmaTel, Texas Instruments, presented by S. Abbas, Centillium) describes an efficient, multi-latency, framing mechanism to support simultaneous transport of channelized voice and data over second-generation ADSL modems (bis versions). This mechanism is proposed for adoption for G.dmt.bis and G.lite.bis. The support of channelized voice in second- generation ADSL modems will require the definition of an appropriate framing and signaling mechanism across the ADSL link. In addition, definition of a dynamic rate repartitioning (DRR) mechanism will optimize the use of available bandwidth across data and voice paths. Companion contributions BI-050 and BI-071 (See the report of G.voice, below) propose a signaling and DRR mechanism related to channelized voice. The proposal in this contribution aims to simultaneously achieve all of the possible approaches to framing requirements outlined in BI- 047. BI-062 (S. Abbas, Centillium) suggests an improvement to the existing single latency framing proposal, which allows independent optimization of the overhead capacity and RS coding gain while optimizing the framing efficiency, and aligning mux data frames with DMT symbols. This alignment should help the DRR/DRA/Bitswap protocols and support programmable fixed overhead capacity. BI-069 (ADC Telecommunications, Aware, Cisco Systems, Ikanos, Legerity, Siemens ICN, SigmaTel, Texas Instruments, presented by S. Abbas, Centillium) suggests EOC messages based on BA-078 (F. Van der Putten, Alcatel) which proposes an ADSL overhead structure for use with the efficient framing proposal that is currently under development in Q4/15. Companion contribution BI-050, Proposed mechanisms to support CVoDSL

signaling over an ADSL link, defines an HDLC-based mechanism to support AOC, EOC and voice signaling functions on a single overhead channel. BI-069 was proposed for agreement, should BI-050 be accepted. BI-094 (F. Van der Putten, Alcatel) is an adaptation of Alcatel contribution BA-078. It proposes an ADSL overhead structure for use with the framing as currently contained in the draft G.dmt.bis and G.lite.bis Recommendations. It proposes that all EOC and AOC messages be sent over a single HDLC-based channel. If multiple PMS-TCs are used, the HDLC channel is allocated to a particular PMS-TC by configuration. BI-106B (T. Cole, AMD, ad hoc Convener) reports on the framing, overhead structure, and overhead protocol ad hoc results. The following papers were discussed: BI-047, BI-048, BI-062, BI-069, BI-094 as they relate to issues: 21.7.3 21.15 21.9 21.16 21.12.2 23.1.1 21.13 24.1.1 21.14 24.5 Without dissent, the ad hoc recommended the following agreements: 1. The CRC shall be carried in the path for which it is calculated, and it shall be carried in a byte-oriented periodic structure, i.e., not using a message format. 2. The following indicator bits are particularly time sensitive and shall be transported in a bit-oriented overhead structure, i.e., not using a message format: a. NTR downstream (PMS-TC related) b. Los and sef in both directions (PMD related) c. Lcd-0, lcd-1, … in both directions (ATM-TC related) d. Lpr upstream (PMD related) 3. All other management primitives currently defined shall be counted locally and shall be communicated within the message-based overhead, e.g., periodic autonomous message reporting, query protocol. 4. All overhead functions, excluding those named in 1 and 2 above, shall be carried in a single message- based overhead structure. These functions include the following (time sensitive message are denoted *): a. *Reconfiguration messages (TPS-TC and PMS-TC and PMD related) b. Read/write protocol (ME related) c. Performance Monitoring (ME related) (i.e., those related to item 3 above) d. Power management (ME related) e. *Voice TPS-TC related f. *Dying gasp (under study) g. Profile management (under study) h. Q-mode related (under study) 5. The bit-oriented structure and the message-based structure shall be carried in the same path. The path is TBD (e.g., path #0, selected path, highest path, path with highest overhead, etc.). 6. The HDLC-based message protocol shall be used in the message structure for all messages based on the protocols used in G.hs and G.ploam. Methods to add additional reliability are for further study. QUIESCENT MODE (Q MODE)

BI-051r1 (A. Carlson, Broadcom) proposes a general framework for Q-mode. Q-mode has been discussed by Q4/15 at least since April, 1998, and since then a number of companies have presented contributions on Q-mode, and two ad hoc discussions have also been held on this as well. Presently, the G.lite.bis and G.dmt.bis issues lists record several agreements regarding Q-mode, but none of these agreements, or any others, take steps toward a specific implementation for Q-mode. This proposal is intended to form the basis for further development of specific Q-mode signals and procedures. BI-052 (A. Carlson, Broadcom) discusses a PRBS (Pseudo-Random Bit Sequence) generator for the semi-stationary Q-mode signal. BA-045, Semi-stationary quiescent mode signal (Orckit Communications), documented the advantages of a semi-stationary Q-mode signal; HC-029r1, Semi stationary Q-mode - detailed signal definition (Orckit Communications), presented a specific proposal for a semi-stationary Q-mode signal. That proposal included a pair of PRBS generators, each with a period greater than 4000. BI-052 proposes to replace that pair of PRBS generators with the existing SHOWTIME data scrambler already defined in G.992.1 and G.992.2.

BI-056 (K. Harris, Nortel) suggests wording for an informative appendix on protection devices to be added to Recommendations G.vdsl, G.shdsl, G.pnt, G.dmt, and G.lite.bis, as agreed in the August – September Huntsville meeting. BI-080 (J. Carlo, M. Locke, Texas Instruments) proposes that the “Non-stationary” signal in Q-mode consist of vendor-specific 4-QAM modulation on the applicable tones for REVERB/SEGUE rather than the specific PRD (Pseudo-Random Downstream) sequence. Minimization of PAR does not necessarily lead to minimum power, and in some cases, power can be better reduced by careful choice of the 4-QAM modulation sequence at the transmitter. Since the receiver is not decoding this signal for data anyway, the transmitter should be given the freedom to minimize power during Q-mode. BI-105 (A. Carlson, Broadcom, ad hoc Convener) is the report of the Q-mode ad hoc. Eleven representatives of nine companies met in an ad hoc session to discuss Q-mode for G.dmt.bis and G.lite.bis. Discussion clarified some Q-mode concepts and resulted in one agreement. The first agenda item proposed that Q-mode be made mandatory. Several members expressed uneasiness with making anything mandatory before it was defined. The discussion evolved to consider, separately, the roles of the transmitter and the receiver in operation of a hypothetical Q-mode. While not willing to grant mandatory status upon Q-mode, the ad hoc agreed that, if Q-mode is defined, and if it is mandatory, then it shall be mandatory at the receiver. In other words, the ad hoc almost, but not quite, agreed that Q-mode could/should be initiated by the transmitter. During Q-mode the transmitter would transmit some kind of Q-mode signal. The receiver would be required to recognize the onset of Q-mode as well as the end of Q-mode. Due to lack of time, no further agreements were reached, but there was a general feeling of support for the following concepts: • Q-mode could/would be initiated independently by the transmitter(s) at either end of a connection. • The transmitter should transmit a low-PAR signal during Q-mode. The ad hoc recommended that the following agreed item be added to the G.lite.bis and G.dmt.bis issues list: Any Q- mode, if required to be mandatory, shall be mandatory at the receiver. EXTENDED PSD MASK

BI-057 (D. Van Bruyssel, Alcatel) proposes to define two annexes in G.dmt.bis and G.lite.bis to support operation without an underlying service: • An annex for an all-digital mode ADSL with improved spectral compatibility with ADSL over POTS (e.g., G.992.1 Annex A) • An annex for an all-digital mode ADSL with improved spectral compatibility with ADSL over ISDN (e.g., G.992.1 Annex B). It was agreed to have two annexes; the text is to be proposed later. Annex I will cover all digital loop with spectral compatibility with ADSL over POTS. Annex J will address all digital loop with spectral compatibility with ADSL over ISDN. These Annexes will mostly be “cut and paste” of the existing Annexes A and B respectively except for the PSD tests. Upstream and downstream PSD texts are agreed for Annex I as contained in TD-058. There is presently no agreement on the PSD texts for Annex J (over ISDN). Nortel and Alcatel will contribute to the next meeting. BI-058 (D. Van Bruyssel, Alcatel) defines the PSD masks for the non-overlapped spectrum operation of ADL, i.e., ADSL without underlying POTS or ISDN. For the downstream direction it was already agreed to use the same PSD mask as in G.992.1 (agreement 6.4.1) and G.992.2 (agreement 12.2.5.1); this contribution therefore concentrates on the PSD mask of the upstream direction. HC-035, Proposed upstream PSD mask for all-digital loop (D. Van Bruyssel Alcatel), showed results on projected performance increase; the achieved gain in capacity and loop reach is significant and justifies the introduction of a new PSD mask. BI-059 and BI-060 discuss spectral compatibility with other services. BI-059 (D. Van Bruyssel, Alcatel) expresses the T1E1.4 consensus on the spectral compatibility of the PSD masks proposed in BI-058, according to Method B of dpANS spectrum management (T1E1.4/2000-002R4, Spectrum management for loop transmission systems, draft, Napa, CA, October 2, 2000). BI-060 (D. Van Bruyssel, Alcatel) addresses the specific spectrum compatibility issues in Europe. In Europe, ETSI has started work on spectral management; TM6 is working on a report, ETSI-DTS/TM-06016-1 (2000), Spectral

compatibility - Classification of signals. This report intends to simplify and harmonize the description of network- specific spectral management documents. Although clear common rules are currently absent, it can be reasonably assumed that by the proof of spectral compatibility according to the dpANS spectrum management (T1E1.4/2000- 002R4), spectral compatibility in Europe will be satisfied: • Proposed changes of the upstream PSD mask (BI-058) fall in the low frequency region, where crosstalk coupling functions are weak. • The type of services tested for spectrum compatibility in T1E1.4/2000-002R4 are similar or identical to services used in Europe, i.e., V.90, BRA-ISDN, G.SHDSL, HDSL. Further, it seems that these rules for spectral management are considered to be network-specific. BI-063 (S. Abbas, Centillium) describes a fast approach for DRR, DRA and Bitswap event signaling. It was presented for information. BI-064 (K. Harris, Nortel) discusses code points for the session aggregate power, session maximum PSD, and session nominal PSD parameters. In the July – August Huntsville meeting, it was agreed that the ATU-C and the ATU-R should indicate these parameters during initialization. This contribution suggests three ways this information can be sent within the handshake; one method makes these parameters general to all recommendations. For G.vdsl it was agreed to support the method that makes these parameters general to all DSL recommendations. The issue remains open for G.dmt.bis and G.lite.bis. DATA COMPRESSION

BI-066 (Y. Kumar, Catena) provides a strawman proposal for the implementation of data compression in ADSL modems. It asserts that the following features of ADSL modems need to be kept in mind when considering the implementation of data compression: • Latency and data rate • The presence of ATM cells in the data payload • The need for multiple streams of data, with varying QoS requirements • The impact of BER, and the consequence of uncorrected bit errors This contribution discusses the present implementation of voice band modems using V.42 for data link error control and also V.42bis and V.44 data compression procedures noting the limitations of such procedures in ADSL; it presents an implementation, which includes ATM header compression, and is therefore better suited to ADSL. Concerns were noted about applying compression at a low OSI layer and maintaining quality and grade of service. BI-067 (J. Heath, Hughes Network Systems) provides information on certain features of the new ITU-T Recommendation V.44, which defines a data compression algorithm for use in modems and other communications networks. One of the features of the algorithm is packet method, in which packets (blocks, frames, etc.) are compressed separately, so that if packets are lost, or received out of order, the packets received can still be correctly de-compressed. This method of data compression provides a packet network with excellent compression ratios without incurring any data expansion when processing uncompressible data. It also allows a mechanism to limit execution time when processing uncompressible data. N. King (Infineon) convened an ad hoc on data compression. The meeting report is BI-114. The ad hoc produced a liaison to SG13 asking thier views on the application of data compression alborithms in xDSL standards. CODING

BI-040 (H. Sadjadpour, R. Sonalkar, AT&T; G. Jin, Mitel) proposes to use the multi-tone turbo trellis coded modulation (MTTCM) technique as an option for the forward error correction in ADSL modems. It describes both the encoder and decoder functions, and includes a recommendation for the decoding of the proposed turbo code. It suggests a procedure to design an interleaver suitable for turbo codes. It also discusses the computational complexity of the decoder and the delay in the system. This issue is open. BI-068 (T. Coolkev, M. Tzannes, A. Friedman, Aware) presents an overview of Low density parity check (LDPC) codes and their properties in comparison with turbo codes, and lists similarities and differences. Both code families have coding gains very close to the Shannon limit; the main difference is that LDPC codes fundamentally do not have an error floor, while turbo codes do.

BI-081 (T. Cooklev, M. Tzannes, A. Friedman, Aware) proposes using LDPC codes in place of TCM for ADSL. It describes a proposal for a multi-level coding scheme for ADSL. It presents the performance of the advanced coding scheme both with and without Reed-Solomon codes, and includes complexity estimates. BI-089 (J. Mueller, V. Mitlin, 3Com) discusses the benefits of using the automatic repeat request protocol (ARQ) together with the currently defined Reed-Solomon forward error correction scheme for improving the data rate and loop reach performance of G.dmt.bis and G.lite.bis. It argues that: • The errors seen over a DSL link are typically not due to AWGN (additive white Gaussian noise) but rather to impulse noise. • ARQ can offer increased performance in both an AWGN channel and, in particular, a burst error channel. • ARQ can mitigate the need for interleaving, thereby allowing the memory and delay associated with interleaving to be reapplied to support ARQ. BI-090 (B. Li, A. Decsky, Catena) proposes a new turbo trellis-coded modulation (TCM) scheme for the ADSL standard. It evaluates, through computer simulations, some performances of this turbo TCM for AWGN channel with and without impulse noise. It presents the coding gains for both cases with and without concatenation of RS codes. It also gives the complexity evaluation of this turbo decoder. This new scheme provides a very good error performance and a low implementation complexity with respect to the other schemes presented so far. BI-092 (D. Van Bruyssel, Alcatel) provides simulated performance results of G.992.1 trellis coding with and without G.992.1 Reed-Solomon coding in BA-108R1 format. BA-076, (F. Van der Putten, Alcatel) proposed the mandatory use in G.992.1 of Concatenated Trellis and Reed-Solomon coding (R£16) for improved coding. These simulations show the interpolated net coding gain (BER = 1e-7) without RS ranging between 3.42 and 3.79 and with RS ranging between 4.93 and 5.25. BI-093 (Mitsubishi Electric) shows the performance evaluation of TTCM(PCCC) proposed in BA-086, (W. Matsumoto, Y. Miyata, M. Narikawa, Mitsubishi Electric). This paper also provides complexity, impulse noise performance and burst error length calculations. These simulations show the net coding gain (BER = 1e-7) without RS ranging between 3.05 and 3.09 dB and with RS ranging between 4.61 and 6.41 dB. BI-095 (E. Eleftheriou, S. Ölçer, IBM) proposes the application of low-density parity-check (LDPC) codes for DSL transmission. It presents simulation results that show that LDPC codes achieve excellent performance for bandwidth-efficient QAM transmission. LDPC codes do not suffer from “error floors” and offer some unique advantages in terms of practical implementation; they therefore represent an alternative to turbo-codes for advanced coding in ADSL. These simulations show the net coding gain (symbol error rate = 1e-7) ranging between 3.5 and 6.2 dB. BI-110 (T. Cole [AMD], F. Van der Putten [Alcatel], ad hoc Conveners) is the report of the ad hoc on improved coding gain. This meeting addressed the G.dmt.bis and G.lite.bis contributions BI-040, 068, 081, 089, 090, 092, 093, and 095. The goal of the meeting was to come up with requirements for the improved coding gain functionality. The ad hoc agreed that the following points shall be requirements for the improved coding gain functionality: • Shall support different bit loading on each of the DMT tones (1 to 15 bits) • Shall support multiple latency paths including low and high data rates • Shall support multiple latency paths including low and high latency • Shall have a TBD minimum coding gain when configured for zero additional end-to-end latency • Shall have a TBD minimum coding gain when configured for high TBD additional end-to-end latency • Shall support seamless reconfiguration of the bits&gains table and the number of bits per symbol from different latency path • Shall support all valid values of number of bits per symbol from a latency path The ad hoc also considered that a bit loading reference scenario would be useful for further improvement and comparison of contributions on the subject of improved coding gain. The strawman proposal is to have linear SNR from (carrier 0, 50 dB SNR) to (carrier 200, 0 dB SNR). The work on a reference scenario was continued during this meeting. In BI-110, it was suggested to evaluate the coding proposals on a channel with non-flat SNR. BI-116 (D. Van Bruyssel, Alcatel) contains a proposal on this subject.

MISCELLANEOUS

BI-026 (K. Barman, D. Kumar, Silicon Automation Systems) proposes that G.dmt.bis and G.lite.bis include the requirement of transmitting pilot(s) on tones with low SNR that do not carry data, as explained in the earlier contribution BA-058 (K. Barman, Silicon Automation Systems; CSR Vol. 11.7). It proposes the following: • G.dmt.bis shall provide for use of low SNR sub-carrier(s), that is (are) not being used for data modulation, for pilot on request by the receiver. • G.dmt.bis shall adopt the text from the reference for providing pilot on low SNR sub-carrier(s). • G.lite.bis shall provide for use of low SNR sub-carrier(s), that is (are) not being used for data modulation, for pilot on request by the receiver. • G.lite.bis shall adopt the text from the reference for providing pilot on low SNR sub-carrier(s). This issue remains open. SAS will continue to try to convince Q4/15 that their solution is needed. Other developers seem to recover clock without using this approach. BI-065 (K. Harris, Nortel) discusses balance requirement with DC bias. Many xDSL modems are deployed without a central splitter, and are designed to share the copper loop with other services including POTS. In these conditions, it is important to ensure that the balance requirement is met under DC bias conditions that may reasonably occur. This contribution recommends that the balance requirement of the ATU-R for G.lite.bis, G.dmt.bis, G.vdsl, and G.pnt be modified to state that the balance requirement be met with –52 V DC bias (North American requirement) applied to one terminal and 0 V bias to the other. This issue was opened. BI-072 (C. Posthuma, Lucent; Nortel) provides three alternatives to provide telephony service when commercial AC power is not present at the integrated access device (IAD) in the customer premise: • Traditional battery feed circuit and a traditional phone • CPE reserve battery • Lower Bit Rate DSL Service similar to the HC-036 (D. Van Bruyssel, Alcatel) proposal BI-072 proposes that protocol “hooks” be included in each of the standards mentioned to enter and exit all three methods. This issue is open in G.dmt.bis and G.lite.bis and was agreed in G.vdsl. BI-073 (J. Mueller, 3Com) discusses ADSL link performance monitoring. An ATU-R can collect valuable information on the characteristics and quality of the transmission link. This contribution requests that a standardized mechanism be defined in G.lite.bis and G.dmt.bis to pass this link information to the ATU-C. A service provider can utilize this information to qualify the link and monitor the quality of service. This contribution requests that the following new issue be opened: Should G.lite.bis and G.dmt.bis specify a standardized mechanism for passing link statistics from the ATU-R to the ATU-C during showtime? BI-088 (K. Harris, M. Pakravan, Nortel) discusses the definition of clipping. The current Recommendations for G.lite and G.dmt specify a clipping rate of 1e-7; it is unclear whether this refers to a sample clipping rate (which can be easily changed into a peak to rms requirement) or a symbol clipping requirement. This contribution recommends that the definition be clarified in the bis versions of the specification and discusses ways of doing this. BI-074 (D. Kumar, Silicon Automation Systems) points out that a table in Section A.4 of BI-R17, draft Recommendation G.dmt.bis (and HC-R18, draft Recommendation G.lite.bis), does not correctly reflect the agreed item in both the G.dmt.bis and the G.lite.bis issues lists (BI-U17 and BI-U18, respectively). Modems in the inactive state, when connected to the line with another modem in the active state, should not significantly attenuate the signal on the line. For this to happen, even the load impedance of the modem in the inactive state should be high, i.e., it should be ZL-Hi and not ZL as proposed in D.812© (J. Mueller, 3Com; Compaq, Pulsecom; seeCSR Vol. 11.5). This is how the agreed items are worded, but the table in BI-R17 Annex A.4 specifies that the load impedance be ZL. This contribution proposes that it be changed to ZL-Hi. Consequently, the first three states in the table should be defined as high impedance states. This was agreed. BI-102 (G, Koppisetti, D. Kumar, Silicon Automation Systems) addresses the unresolved topics in the section A.4 of BI-R17r1. It provides the minimum impedance levels for the high impedance state, and some clarifications to facilitate further progression of the development of the G.dmt.bis and G.lite.bis Recommendations. BI-103 (G, Koppisetti, D. Kumar, Silicon Automation Systems) provides the working text of the specific requirements for ADSL CPE modem (active state) in the normal impedance state (Annex A.4 of the bis version). This shall be a separate section in the Annex A of the bis version. The ATU-R can be designed with an external

splitter, or with the high pass filter (HPF) built into it. This document describes the characteristics of the ATU-R + HPF in the normal impedance state. It does not describe the characteristics of ATU-C in the normal impedance; this shall be taken up separately. G.SHDSL BI-R15 (S. Blackwell, Centillium, Editor) is the draft G.shdsl Recommendation. BI-U15 (S. Blackwell, Editor) is the updated issues list. BI-A15 (S. Blackwell, Editor) is the agenda and work plan. BI-029 (S. Blackwell, Centillium) contains a list of proposed changes to the G.991.2 white contribution to the February 2001 meeting in Geneva. The proposed changes are editorial in nature and represent an attempt to correct the known inconsistencies in the current version of the document. BI-028 (S. Blackwell, Centillium) proposes text clarification for SNMP support using the EOC. The G.shdsl EOC channel includes a message (Message 121) that is intended to provide a mechanism for the support of G.997.1 encapsulated SNMP messages. However, in its present form, the defining text for that message is not sufficiently clear to assure that implementations from different vendors will interoperate in this area. This issue remains open. BI-027 (S. Blackwell, Centillium) proposes clarifications to four-wire framing for ISDN and ATM TPS-TCs. For most of the TPS-TCs specified in Annex E of G.991.2, the current text is very clear as to the framing and the ordering of data for the optional four-wire mode. But in the ISDN BRA and ATM sections, four-wire framing is not described. This contribution proposes text for both sections to clearly specify the framing to be used by the ATM and ISDN BRA TPS-TCs (§E.9 and §E.8, respectively) in the optional four-wire mode. This issue remains open. BI-030 is a liaison from TM6 on commonalities between ETSI SDSL and ITU-T G.shdsl, in reply to HC-083r1 (CSR Vol. 11.8). TM6 is aware that minor differences exist between the ETSI SDSL specification and the ITU G.shdsl draft specification. As part of the ongoing work of merging the two published parts of the SDSL specification into a single document, TM6 intends to identify and resolve those differences in the combined ETSI SDSL document. Those differences that cannot be resolved will be listed in an informative section of the combined SDSL document. For the combined SDSL document, TM6 agreed to use the existing G.hs code-point structure of G.shdsl Annex B with the possible addition of new ETSI-specific code-points, if necessary, within the existing G.shdsl code-point structure. BI-041 is a liaison from ETSI TM6 on dual bearer mode for SDSL. At their September meeting (No. 19) in Vienna, Austria, TM6 agreed to adopt the text of Annex E.10 of G.shdsl. The ANAI (Access Network Architecture and Interfaces) group studied the content of E.10; to align the text with the specific European requirement, TM6 proposes additions and changes to E.10.2, dual bearer mode types. BI-042 is a liaison from ETSI TM6 on SDSL ATM-TC EOC messages. At their September meeting TM6 agreed to align the text of ETSI SDSL with ITU-T G.shdsl. According to this agreement, they compared the ETSI and ITU-T EOC messages relevant to SDSL ATM-TC status, and agreed to the following: • To choose, for the values of a and d parameters, pertinent to cell delineation, the values 7 and 6, respectively. • To choose, for the number of contiguous frames, during which the condition of LCD defect is present, and required to declare LCD failure, the value 9. • To align the relevant portion of living list study point ATM TC layer for SDSL to the ITU-T text; however, some additional improvements have to be brought to the ITU-T text. TM6 reports that several delegates, mostly representing network operators, noticed that the indicator bits used for loss of cell delineation (LCD) failure reporting do not allow the build up of consistent availability statistics, e.g., based on the severely errored seconds measurements, that take into account the duration of the failure. TM6 proposes that a viable solution would be one based on a regular (e.g., every one second) autonomous generation of messages, as was proposed in the previous ETSI liaison to ITU-T from May 2000 (BA-098; CSR Vol. 11.7), even keeping the ITU-T proposed information field layout for the OAM message. BI-108 contains the response to BI-042. It includes the latest text for EOC messages dealing with cell delineation, with changes from this meeting indicated, and notes Q4/15 comments on two of the issues raised by TM6: • Failure reporting: Q4/15 has added an ACK mechanism such that the LT is guaranteed to receive the message; there is therefore no need to send a message every second for fear of one getting lost. • Building of statistics: polling can be used to establish availability statistics. The polling interval is left up to the STU-C and could be set to 1 second or some other value. Q4/15 believes that such a method sends messages

over the EOC in cases when it is necessary, rather than mandating the generation of autonomous messages every second over the EOC in all cases. BI-053 (D. Daecke, Infineon; Adtran, Siemens) proposes a small modification to the text of section E.9.4.7 and E.9.4.8 dealing with OAM for ATM over SHDSL. With the current mechanisms, the possibility exists of a message being sent from the NTU, corrupted during transmission and never received at the LTU. This contribution proposes that the existing section E.9.4.7 EOC ATM Cell Status Request Message Format – Message ID 17 be modified to act as an acknowledgment message. This was agreed. BI-054 (D. Daecke, Infineon) proposes editorial modification of the section E.9.2, Reference model for ATM transport, to reach alignment with ETSI SDSL, as was proposed in HC-083r1 (R. Stuart, Q4/15 Rapporteur), from the July – August meeting in Huntsville, Canada. This was agreed. BI-055 (D. Daecke, Infineon; Siemens) proposes editorial corrections for the text of Annex E.8, TPS-TC for synchronous ISDN BRA; it resolves ambiguities and adds clarifying notes. This was agreed. BI-021 is a DSL Forum liaison addressing IETF MIBs for SHDSL; it proposes changes to the HDSL2/SHDSL draft MIB for the IETF ADSL working group to consider before the last call is made. Q4/15 did not find any issues with this work but decided not to respond as Q4/15 was only copied on the document. BI-022 is a DSL Forum liaison on their testing and interoperability activities. The DSL Forum has scheduled ADSL interoperability testing sessions to prepare for the CES 2001 show staging on December 13 - 20, 2000, to be held at the University of New Hampshire, Durham, New Hampshire. The DSL Forum is progressing the new work item on G.shdsl interoperability. The test plan for G.shdsl interoperability test events is progressing well. At their August – September meeting, the DSL Forum identified the following area for clarification: How is G.994.1 (G.hs) intended to operate with G.991.2? The SHDSL Consortium at the University of New Hampshire InterOperability Laboratory held the first G.shdsl interoperability test exercise during the week of October 23, based on the DSL Forum’s G.shdsl test plan. The next DSL Forum meeting will take place in Portland, Oregon, December 5 - 8, 2000. G.VDSL BI-R11 (S. Palm, Broadcom, Editor, is the draft G.vdsl Recommendation. BI-U11r2 (S. Palm, Broadcom) is the updated issues list. BI-A11 is the agenda and work program for G.vdsl at this meeting. BI-025 (J. Bostrom, Ericsson) presents the output from the TM6 September meeting in Vienna, Austria, relevant to the issues list for G.vdsl published as HC-U11 of the August-September Q4/15 meeting. The comments on the open issues are based on the ETSI Transceiver Specification for VDSL (TS 101 270-2). The specification was forwarded to the ETSI TC TM Chair for a decision on publication; the result of the approval process is expected to be available at the next TM6 meeting scheduled for November 27 – December 1, in Monterey. TM6 is continuing their work on VDSL transceivers; they expect that this will lead to an Issue 2 of TS 101 270-2. Work on the Fx plan and others is to be continued under a new work item. TM6 recommends that, as far as possible, the ETSI (European) requirements be included in the G.vdsl requirements to avoid the need for a separate regional annex for Europe. TM6 decided to modify the text in Section 5.2 of the transceiver specification, which specifies upstream power back- off, to align with the spirit of the agreements reached by Q4/15 in Huntsville. However, the new text included in Section 5.2 does not require that the reference PSD shall be independent of noise model (Issues list item numbers 8.1 and 8.9). TM6 decided to open a new WI to study the market requirements for VDSL services to determine the need for any additional band plans, such as the Fx plan (Issues list item number 2.10.2). BI-061 (V. Oksman, Broadcom) discusses the definition of LOSS function for upstream power back-off (UPBO). The agreement on the UPBO mode (issue 8.16 of the G.vdsl issues list) requires usage of the electrical length and of the LOSS function as two main parameters to set the upstream transmit PSD mask. BI-061 presents a generic view on the definition of electrical length and shows that usage of electrical length causes certain limitations on the approximation for the loop loss function. It suggests definition of a reference loop for UPBO purposes that approximates popular VDSL loops with sufficient accuracy. The simulation results show the accuracy of approximation for several popular types of loops by two different models of reference loop. BI-079 (Bell Canada, BT, France Telecom, Korea Telecom, SBC, Swisscom, Telecom Italia, Telia developed by D. Clarke and M. Patel, BT) suggests some network topologies for VDSL upstream power back-off analysis which are of interest to network operators; it was presented for information.

BI-085 (S. Schelstraete, Alcatel Bell; V. Oksman, Broadcom; Aware, Cadence, Ericsson, ETRI, IBM Research, Ikanos, Infineon, Italtel, Lucent, Mitel, Mitsubishi, NEC, Next Level Communication, Nortel, Samsung AIT, SK Telecom, ST Microelectronics, Telia, Texas Instruments, Toshiba) proposes an improved working text for the VDSL out-of-band PSD mask. At the January-February, 2000 Q4/15 meeting in Fiji, it was agreed to use FI-140R1 as the working text for the PSD mask in the stop band. Some parameters in that contribution required further study; this contribution proposes values for these parameters, clarifies some details of the proposal, and aligns it with the last agreements of ETSI TM6. It was agreed to use BI-085r1 as the new working text for the PSD mask in the stop band. BI-086 (S. Schelstraete, Alcatel Bell; V. Oksman, Broadcom; Aware, Cadence, Ericsson, ETRI, IBM Research, Ikanos, Infineon, Italtel, Lucent, Mitel, Mitsubishi, NEC, Next Level Communication, Nortel, Samsung AIT, SK Telecom, ST Microelectronics, Telia, Texas Instruments, Toshiba) proposes a working text on VDSL UPBO. At the August-September Q4/15 Huntsville meeting, a text was agreed (HC-082) for the definition of UPBO in VDSL. BI-086 contains text based on that agreement and on work done in ETSI TM6. This work has resulted in four basic statements specifying the exact application of the UPBO mode, and some minor changes to the original ITU proposal for the mode itself (see also BI-025). BI-086 proposes text for the working text for VDSL UPBO in ITU, complementing and clarifying the agreed item 8.16. This was agreed. G.PNT BI-R12 (J. Magill, Lucent, Editor) is the draft Recommendation G.pnt.f, Phoneline networking transceivers – foundation. BI-U12 is the updated issues list. BI-056 and BI-065 (see G.gen above) were added to the open issues list for G.pnt. G.LITE.BIS BI-R18 (T. Cole, AMD, Editor) is the draft G.lite.bis Recommendation. BI-U18 is the updated issues list. BI- A18 is the agenda and work plan for G.lite.bis. D.665©, D.663©, BA-090, HC-022 and HC-023 discussed the issue of egress xDSL signals causing interference into adjacent AM radio receivers. They also discussed the diversity of in-house wiring, the large number of untwisted drops, and the use of Solid State Protectors, all of which increase the likelihood of egress from a cable. Due to the spectral allocation of G.lite an egress compliant mask can be provided with little degradation to the achievable data rates. BI-043, North American Egress compliant mask for G.lite (K. Harris, Nortel), suggests defining such a mask as a proactive step to addressing this cross-industry concern. There is of course a similar egress concern for services other than G.lite. However, many of these services are not intended to use uncontrolled home wiring. The impairments on the distribution portion of the network are very operator dependent. In some areas there may be no use of untwisted drop or solid state protection devices. BI-043 summarizes data presented in previous contributions and presents masks that would provide suitable protection. This was already rejected by T1. Some delegates state that one should wait for regulatory actions prior to taking any action on this item. Whether the template for PSD applies to the receiver or to the transmitter can be discussed. There are several possibilities, e.g., improve the balance, or go to G.dmt with better cable control. As there was no agreement, the issue is open. BI-097 (B. Barazesh, R. Banerjea, Lucent) proposes to modify fast retrain to remove the profiles for G.lite.bis. It proposes to increase training time by less than one second to allow the transceivers to train sufficiently to exchange new rates and B&G tables. Removal of the profiles and addition of extended training will allow for a more robust fast retrain sequence with the benefit of a short retrain for changing line and interference conditions. G.DMT.BIS BI-R17 (F. Van der Putten, Alcatel Bell, Editor) is the draft G.dmt.bis Recommendation. BI-U17 is the updated issues list for G.dmt.bis. A review of BI-R17 and also the text of BI-034, PMD text for G.dmt.bis, was conducted. In figure 8-4 of BI- 034, showing the primitives, there should appear a clock synch primitive. In table 8-4, the definition of NSc should be revised. The content of BI-034 will be included into the draft of BI-R17. In review of the issue list BI-U17, the text of the European Annex on ingress is left in the draft Recommendation; there was no consensus to remove it: J. Besseyre (consultant to GlobeSpan) supported the removal of the European Annex as it is technically wrong and ETSI TM6 is expected to prepare a new text at the Monterey meeting in November.

BI-075, G.dmt.bis; Performance Requirements for Region A (North American) with RFI Ingress (K. Harris, Nortel Networks), proposes rates for the North American annex of G.dmt.bis for the tests with ingress model 1 and model 2 present. These were based on the proposal made in FI-097, with the change in rate suggested in HC-053 for the downstream Mid-CSA loop. BI-082 (D. Van Bruyssel, Alcatel; A. Redfern, Texas Instruments) proposes downstream data rates for category I performance requirements with crosstalk and RFI. The results are based on simulations and testing of the already agreed test cases using the RFI ingress models 1 and 2. The goal is that these data rates be accepted as target data rates. Per agreement 3.1.7 of BI-U17, the target rates are considered working text; they are expected to be increased as improvements are added to the standard. BI-083 (L. Humphrey, Nortel) is based on a proposal made to ETSI TM6 (Vienna WD-01) for upstream PSD masks for ADSL that can be used where there is no underlying POTS or ISDN service to provide increased upstream capacity. It proposes two masks, one for countries where ADSL over ISDN is allowed to be deployed, and one where it not. This issue is open. G.HS.BIS BI-R16© (L. Brown, Motorola, Editor) is the draft G.hs.bis Recommendation. BI-U16 is the updated issues list. BI-046 (L. Brown, Motorola) is the first draft of an Implementers Guide for the published version of G.994.1. BI-098 (M. Jong-Hyuck Park, Samsung AIT) proposes the code points for G.hs.bis to support G.vdsl mode for MCM-based VDSL. The use of the proposed code points is for VDSL modems based on multi-carrier modulation (MCM) only. The mode of operation between MCM and SCM VDSL is distinguished by a SPar(1) bit in the standard information field. This contribution is the revised version of the MCM-based VDSL handshake that was agreed to be included in the multi-carrier sections of ETSI VDSL specification and the ANSI MCM VDSL draft standard at the Vienna TM6 and Vancouver T1E1 meetings. This contribution is for G.hs.bis and G.vdsl discussions. BI-108 (M. Jong-Hyuck Park, Samsung AIT; T, Pollet, Alcatel, Aware, Inc., Cadence, Ericsson, ETRI, IBM Research, Italtel, Mitel Co. Mitsubishi Electric Co., NEC, Nortel Networks, SK Telecom, ST Microelectronics, Telia AB, Texas Instruments, Toshiba) discusses standardization of G.vdsl-related G.hs work. G.hs defines signals, messages and procedures for exchanging these between DSL equipment, when the modes of operation of the equipment need to be automatically established and selected. G.hs will be used for G.vdsl (agreed issue 3.2 on G.vdsl open issue list). Dependencies between G.vdsl and G.hs can jeopardize timely progress in G.hs. BI-108 intends to stimulate discussion on eliminating these dependencies and how the two recommendations can progress in parallel. BI-112 (L. Brown, Motorola, G.hs.bis Editor) is the report of the G.hs.bis ad hoc. During the discussion of BI- 108 in the G.hs.bis session of the main meeting, it was noted that ETSI is using G.994.1 for the multi-carrier variant of their VDSL standard that is out for ballot, and that they had assigned specific G.994.1 code points for their own use. Recognizing that G.994.1 would be used for several variants of VDSL including the ETSI standard(s), the ANSI T1E1.4 Technical Report(s), and ITU-T Recommendation G.vdsl, an ad hoc was convened to discuss how best to coordinate the use of G.994.1 for all of these specifications. The ad hoc concluded that: • Duplication of text, including G.994.1 code point definitions, in multiple documents should be avoided since it introduces unnecessary administrative difficulties in keeping all of the documents synchronized and since failure to do so results in interworking problems; • Interworking between variants of VDSL that use G.994.1 should rely on the G.994.1 protocol (code points), not on G.994.1 signaling (tone sets); and therefore agreed that: • A separate SPar(1) bit should be assigned to each variant of VDSL: Application for the assignment of an SPar(1) bit for the multi-carrier mode of ETSI TS 101 270-2 should be made immediately, according to the procedure detailed in G.994.1 Appendix IV. • A communication should be sent to ETSI Technical Committee TM detailing the proposed actions taken and recommendations of ITU-T Q4/15:

- ETSI TM should remove the duplicated text taken from G.994.1 and refer to the appropriate sections of G.994.1 as applicable. - Encourage correspondence and cooperation between ETSI TM and ITU-T Q4/15 on the definition of signaling (tone sets) within G.994.1 to support VDSL. - Inform ETSI TM about the procedure for approving new code points in G.994.1 (G.994.1 Appendix IV). - Indicate that the code point tables (not the definitions/meanings of each of the bits) may be placed in either G.994.1 or ETSI TS 101 270-2. As a minimum, the SPar(1) bit in G.994.1 would refer to the multi-carrier mode of ETSI TS 101 270-2. • A communication should be sent to ANSI T1E1.4 concerning the use of G.994.1 for the various VDSL specifications informing them of the actions taken by Q4/15 to support the multi-carrier mode of ETSI TS 101 270-2. BI-112 includes Attachment 1, the proposed text of the ETSI TM communication. G.PLOAM.BIS BI-U19 (S. Abbas, Centillium, Editor) is the updated issues list for G.ploam.bis. Regarding BI-086 (text for VDSL UPBO), it was agreed that the network management system shall set the limiting transmit PSD mask for the VTU-R to one of the standard transmit PSD masks to be defined by the VDSL Functional Requirements. The method to determine this limiting transmit PSD mask is for further study. It was noted that the IETF is working on a MIB for VDSL. G.TEST.BIS BI-R13 (M. Tzannes, Aware, Editor) is the G.test.bis draft Recommendation. BI-U13 (M. Tzannes, Aware, Editor) is the updated issues list for G.test.bis. BI-113 (M. Tzannes, Aware, Editor, G.test.bis) is a proposed liaison to ETSI regarding RFI testing. It informs that G.test.bis (G.996.1 Issue II) was Determined at the last ITU SG15 meeting and is scheduled for Decision at the next ITU SG15 meeting in February 2001. The Determined version of G.test.bis contains RFI test procedures and RFI models for North America. The Determined version of G.test.bis does not contain RFI models for Europe, but Q4/15 has agreed to include the European RFI models from BA-059 (L. Humphrey, Nortel) in a future version of G.test. It asks that ETSI provide Q4/15 an update on the status of the European RFI models in ETSI. G.REF.BIS BI-R14 (S. Abbas, Centillium, Editor) is the draft G.ref.bis Recommendation (white paper). BI-U14 is the updated issues list for G.ref.bis. G.VOICE BI-U10 (C. Hansen, Intel, Editor) is the updated issues list for G.voice. BI-A10 is the agenda and work program. It was agreed that Q4/15 should proceed with the drafting of a Recommendation at least to establish a set of requirements on DSL systems to carry voice; channelized voice over SDSL would not be affected by this approach. BI-020 is a liaison from the DSL Forum on STM requirements for Voice over DSL, from their September meeting in Dublin. The DSL Forum has approved TR-036, Requirements for voice over DSL. TR-036 includes Annex A on broadband loop emulation service (BLES). TR-036 is publicly available on the DSL Forum web site . The VoDSL WG added STM transport of VoDSL to its living list at its May meeting in Orlando. Further contributions on this topic were received in Dublin, and text was included into the living list. This liaison also lists some concerns raised about the system level complexity of this approach: • Concerns about the traffic management of an ATM layer sitting on a physical layer that dynamically changes (at the frequency of on- and off-hook events). In particular how cell rate changes are dynamically reflected in the Connection Admission Control and cell scheduling aspects of the ATM layer. • Network management of an ATM layer that sits on a dynamic physical layer. • Control and Management Plane interactions between narrowband and broadband partitions (i.e., cross layer management issues). The DSL Forum has agreed to further investigate the system-level ramifications of this approach. Some potential benefits are:

• Lower latency across the DSL • Simplification of CPE • Simplification of narrowband voice delivery across the DSL access network BI-024 (B. Wiseman, Texas Instruments; Analog Devices, Aware, Centillium, Cisco, Catena Networks, Motorola, Siemens, SigmaTel, Legerity) contains the proposed baseline text for channelized (STM) voice over DSL, currently on the DSL Forum VoDSL sub-working group living list. This text is considered preliminary; it has been reviewed, but not officially endorsed by the DSL Forum. BI-049 (S. Abbas, Centillium) discusses some potential approaches to support signaling for CVoDSL on an ADSL link. There are two commonly employed techniques for telephony signaling, namely, state-based and message-based signaling. This signaling information is carried across a physical layer in-band or out-of-band. In- band signaling uses overhead in the same path as the voice data to transport the telephony signaling information. Out-of-band signaling uses messages that communicate the telephony signaling information in a path that is not the same as voice data. Out-of-band signaling may use an exclusive path or a path shared by other control and management functions across the physical layer. BI-050 (ADC Telecommunications, Aware, Cisco Systems, Ikanos, Legerity, Siemens ICN, SigmaTel, Texas Instruments, presented by S. Abbas, Centillium) describes mechanisms to support channelized voice signaling over an ADSL link. Support of channelized voice requires the definition of an appropriate framing and signaling mechanism across the ADSL link. In addition, definition of a Dynamic Rate Repartitioning (DRR) mechanism would optimize the use of available bandwidth across data and voice paths. Companion contributions BI-048 and BI-071 propose framing and DRR mechanisms related to channelized voice. This contribution proposes an HDLC- based channelized voice signaling approach that optimizes the use of HDLC framing and can simultaneously supports EOC, AOC, channelized voice signaling and other overhead related information on a single HDLC channel. This HDLC-based signaling mechanism can support both CAS and CCS signaling. In addition, it proposes the support of in-band CAS signaling based on the well-known robbed bit signaling approach. If a subscriber uses channelized voice service, then only one of the above signaling scheme would be used and this would be negotiated during startup. It was agreed to open two issues: • Should the definition for channelized voice go into DSL? • Should signalling message be carried in the overhead EOC or/and in the bearer? BI-071 (B. Wiseman, Texas Instruments; Cisco, PairGain) proposes a mechanism for dynamic rate repartitioning (DRR) for channelized voice over DSL (CVoDSL) systems. It is based on the current DRA messages and will be adapted to G.bis framing messages. BI-104 (C. Hansen, Intel) proposes that G.voice contain a functional interface for voice terminals. For discussion, it lists a basic set of functions to be encompassed by a functional interface for a voice terminal. Once the set of functions are defined, a way forward may be to associate events in the PHY or PMS-TC layer with actions on the interface. Other potential issues may be a mapping of the functions onto some common voice distribution transports, such as POTS and ISDN. Jacques Besseyre, Telecomsult S.A.R.L.

Note: The meeting roster from Q4/15 was not available.

November 2000 Vol. 11.10 Copyright © CSR 2000 55 COMMUNICATIONS STANDARDS REVIEW REPORT OF TR-29, FACSIMILE SYSTEMS AND EQUIPMENT NOVEMBER 1 – 2, 2000, ARLINGTON, VA The Chair of TR-29 is H. Silbiger (Lucent). The minutes of the previous meeting (TR-29/00-11-01) were reviewed and approved. TR-29.4 did not meet. Since TIA has agreed to merge TR-29 into TR-30 as TR-30.5, this was the 161st and last meeting of TR-29. TR- 29 can look back on a long and illustrious history as one of the principal contributors to the technological progression of facsimile. Chairs during the last 20 years were Ralph Grant, Steve Urban and Herman Silbiger. Facsimile is now mature and is no longer at the forefront of technology. The principal work foreseen is responding to advances in transmission technology rather than improvements in the facsimile protocol itself. TR-30.5 will meet for the first time in March, 2001. Since the current chair, H. Silbiger (Lucent), will no longer be active in facsimile standardization, an election for a new chair was held. J. Dahmen (Jim Dahmen Consulting) was nominated and unanimously elected to serve as chair of TR-30.5. TR-29/00-11-14 is the proposed charter for TR-30.5. TR-29 has previously been notified about the following IPR items: • Fujitsu has some intellectual property on sending voice files in T.30. • Mixed Raster Content - Xerox may have IPR related to this work and has submitted an IPR statement. (See TR- 29/96-11-55). Xerox also submitted a new patent statement on Mixed Raster Content at the March-April 1999 SG8 meeting, but it was later withdrawn. • JBIG2 - Xerox may have IPR related to this work with respect to the rendering of JBIG-2 images, and there also may also be additional patent claims related to JBIG-2. • Internet Fax – D. Duehren (Brooktrout) is aware of Intellectual Property associated with dial forwarding. D. MacTaggart (Cyberfax) is aware of potential IPR that may apply for real time fax over the Internet. There are patents from Biscom, Matsushita, and Open Port on some aspects of Internet fax (see http://www.patents.ibm.com for details on US patents). J. Dahmen (Lanier) is aware of a patent owned by Infotrieve on a device to convert between fax and email formats. This may have an impact on some Internet fax related gateway products. • Fax Security - There is IPR on the security page from France Telecom and on public key management from RSA. H. Silbiger reported on the ITU World Telecommunication Standardization Assembly in Montreal. The four fax questions proposed by SG8 were combined into one question in SG16 (TR-29/00-11-05), Facsimile terminal capabilities and operation on GSTN and ISDN. The drafts which were Determined at the April 2000 SG8 meeting and further edited at the June Rapporteur’s meeting were approved for Decision at the November SG16 meeting. The following projects will be closed due to lack of activity: • PN-3130, Class X • PN-3625, Class 2.1 The final text for PN-3626 (Class 1.0), retrofitting ITU-T T.31 for incorporation in an updated TIA-578-B, was approved for publication, but it has not yet been published. The following interim standards have been rescinded: IS Title Recision PN IS-650 MultiFunction Peripheral Interface Standard (MFPI) Level 1 PN-4850 IS-134 Facsimile Digital Interfaces- Amendments to TIA/EIA 592 to Support ITU-T PN-4851 T.30 1993 Interim Standard. IS-141 Routing of Group 3 Facsimile Message Utilizing the Subaddress PN-4852

PN-3675, EXTENDED NEGOTIATIONS

It was agreed to send out the draft of an interim TIA standard on extended negotiations within Group 3 facsimile for committee ballot at the previous meeting. The prospects for an ITU version are small. The Chair will contact the editor. It was proposed to close the project at the next meeting if there is no further activity.

PN-3799, I NTERNET FAX

The ITU contribution on V.34 to T.38 gateways had been further edited as agreed at the August meeting. It was submitted to and approved by ITAC-D as a US contribution to SG16. This is a current project and will remain open. TR-29.1/00-11-12 is the report from the ad hoc group that reviewed the delayed contributions to SG16. This report is summarized below: TR-29/00-11-03©, Proposal for Amendment in T.38 regarding Message Flow for V.8 Signal (Canon, Matsushita, NEC, Oki, Ricoh, Toshiba, same as D.15(WP1/16)©), was reviewed. The proposed change is an implementation detail and not part of the standard. Recommendation T.38 intentionally does not discuss any details of spoofing so this proposal is not pertinent. TR-29 does NOT support this contribution. TR-29/00-11-04©, Data rate change handling for V.34 half-duplex fax operation over T.38, using externally initiated retrains (Surf, same as D.31(WP1/16)©), was discussed. In the V.34 half-duplex over IP, a mechanism is required to avoid data overflow and underflow in the gateways. This can be obtained by rate adaptation between the two V.34 half-duplex connections and by reflection of the retrain, change requests and restart events between both connections. TR-29/00-11-04© notes that a clear procedure must be defined in Rec. T.38 to ensure this in a way supported by the V.34 half-duplex standard. To avoid interoperability problems, this procedure should not involve any changes in the current V.34 standard. A mechanism to help synchronize the beginning of control data is suggested as well. TR-29 considered this contribution to have merit but the implications of the contribution need to be evaluated. This topic was identified for additional work. TR-29/11-08©, Proposal for Amendment in T.38 Annex B – Normal connection and disconnection sequence (Canon, Matsushita, NEC, Oki, Ricoh, Toshiba, same as D.16(WP1/16)©), had been agreed at the June Rapporteur’s meeting. At June meeting, draft H.323 Annex D version 2 (GMD-23) was introduced. It describes the detail switching sequence between voice and fax. In comparison with that, the normal connection and disconnection sequence previously agreed in TD-299 (T.38 Appendix II) seems to be insufficient. But it is not appropriate to repeat the detail sequence in T.38 Annex B because of maintaining compatibility issues. This proposal to change this description to refer to the draft H.323 Annex D was supported. TR-29/11-09© (Canon, Matsushita, NEC, Oki, Ricoh, Toshiba, same as D.38(WP1/16)©) proposes an additional new section to T.38 IAF (Internet Aware Fax) device and requests clarification in UDP (User Datagram Protocol) mode. It was agreed in principle that there are timing issues with IAF aware devices operating in UDP mode. The proposed change of extending the T.30 timeout in the IAF to allow for the sending of the TCF (T.30 training check) pattern seems appropriate. No opinions were rendered on the following three documents: TR-29/00-11-06, SIP T.38 Call Flow Example and Best Current Practice (F. F. Mule, Clarent), is an IETF draft . The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt. TR-29/00-11-06 gives examples of SIP call flows for T.38 Internet fax communications (SIP, the Session Initiation Protocol, is defined in RFC2543; T.38 is an ITU-T Recommendation). Elements in these call flows include SIP User Agents, SIP Proxy Servers, and Gateways to the PSTN (Public Switch Telephone Network). TR-29/00-11-06 introduces best current practices for T.38 fax calls: a call starts with audio capabilities, and, upon fax tone detection, T.38 fax capabilities are negotiated. The T.38 fax call scenarios include the detection of T.38 fax transmission by the receiving side, or the emitting side, or both. TR-29/00-11-10©, Information for T.37 Internet Fax Work Plan (Canon, same as D.45(WP1/16)©), delineates extensions to Rec. T.37 to be studied: • Support for Full Mode enhancements • Support for new image compression capabilities • Support for non image transmission capabilities • Support for Group 4 • T.37 over mobile packet networks • T.37 Internet aware terminals • T.37 quality of service Terminal Mode was proposed in Q4/8 Rapporteur’s meeting at Gaithersburg on June 2000 (GMD-19, see CSR Vol. 11.8). The Terminal Mode supports the transfer of image data, capabilities exchange and confirmation for Store and

Forward internet fax terminals having limited memory and small CPU power. Terminal Mode also supports all features of Group 3 facsimile on the Internet using T.30 signals in the capability exchange. The proposal in TR- 29/00-11-11©, T.37 (Canon, Oki), is the updated version of Terminal Mode based on the results of the discussion in Gaithersburg. PN-3825, MULTIMEDIA FAX PROTOCOL (T.30)

Amendments to Rec. T.30 were drafted to add V.92 modulation to Group 3. It had been agreed to send the draft to ITAC-D as a proposed US contribution. After the close of the August TR-29 meeting, Conexant objected to the document going forward as a proposed US contribution. At the ITAC-D meeting, M. Mehta (Nortel) withdrew the document. TR-29 felt that M. Mehta had no authority to withdraw the document, but should have proposed it as a company contribution. TR-29/00-11-07 (K. Chu, Conexant) documents Conexant’s objections to the addition of V.92 modulation to G3. Concerns are raised about each of the three major functions of V.92: PCM upstream, short startup capabilities, and the ability to put a pair of connected modems on hold. Modem-on-hold allows for terminals to interrupt a current data connection and place the modem in a suspended state. Users can take incoming (call waiting) or initiate outgoing voice calls without losing the data connection. Modem- on-hold is a negotiated operation between server and client. The point here is that this function can be open ended in terms of allowed interrupt time. This is counter to the existing timeouts in T.30. Short phase 1 and phase 2 startup is a reduced connecting time mode for V.92 modems, after they have established the same connection on a previous occasion. Client modems may store profiles of the prior connection with the assumption that most of the connection characteristics will not change on a connection-by-connection basis. The problem for facsimile is that V.92 has no mechanism to indicate that a short phase 1/short phase 2 connection attempt is a facsimile session. PCM upstream is the name given to the modulation used for the transfer of data from client to the server for V.92. The benefits of PCM upstream are higher data throughput in this direction. The current maximum for existing facsimile terminals is 33600 bit/s using V.34 modulation. V.92 has as its maximum rate 48000 bit/s, which is a best-case design parameter. In real life connections, upstream data rates will be mostly in the 40000 bit/s region, with higher data rates being a rare occurrence. Another aspect of the modulation data rates for facsimile terminal consideration is that there is no mechanism in T.30 to select the priority of upstream and downstream data rates. T.30 must be able to manage this aspect of V.92 connectivity in order to be useful. TR-29 discussed these issues. It was agreed unanimously that Conexant had not found any technical problems with the contribution. Some of the objections raised were related to the utility of the proposal. The modem-on-hold could be handled by an application making use of a procedure interrupt call. The proposal should be discussed again at the next committee meeting for resubmission to SG16 as a company contribution, if Conexant continues to disagree. It was noted that the IEEE has taken on the standardization work of the Internet Printing Protocol, which previously took place in the IETF. TR-29/00-11-13 is a liaison to the Printer Working Group (Chair, D. Wright), offering TR-30.5’s (formerly TR-29) technical fax expertise. It was approved.

TR-29 MEETING ROSTER, NOVEMBER 1 – 2, 2000, ARLINGTON, VA Herman Silbiger, Lucent Technologies TR-29 Chair Host: TIA 3Com Fred Lucas Conexant Mahdi Zaidan Dialogic Mike Spann Lanier World-wide Jim Dahmen Lucent Technologies Herman Silbiger Telogy Shahid Akhtar

ACRONYM DEFINITIONS 3GPP Third Generation Partnership Project (ETSI) ABT Adaptive Block Transform AC Alternating Current ACK Acknowledgment ADSL Asymmetric Digital Subscriber Line AM Amplitude Modulation AN Advisory Note AOC ADSL Overhead Channel ARQ Automatic Repeat Request AT Access and Terminals (ETSI Committee) AT Asynchronous Terminal ATAAB Analog Technical Ad hoc Advisory Board ATM Asynchronous Transfer Mode ATU-C ADSL Transceiver Unit - Central Office End ATU-R ADSL Transceiver Unit - Remote Terminal End AVT Audio/Visual Transport AWGN Additive White Gaussian Noise B&G Bits&Gains (Q4/15) BER Bit Error Rate BOF Birds of a Feather BRA Basic Rate Access BRI Basic Rate Interface CAS Channel Associated Signaling CATV Cable Television CCS Common Channel Signaling CEC European Committee for Standardization CEN Commission Europeenne de Normalisation (European Standards Committee) CENELEC Commission Europeenne de Normalisation Electrotechnique (European Electrotechnical Standards Committee) CIF Common Intermediate Format CISPR International Special Committee on Radio Interference CLI Calling Line Identification CO Central Office CPE Customer Premise Equipment CRC Cyclic Redundancy Code CSA Canadian Standards Association CVoDSL Channnelized VoDSL DC Direct Current DCE Data Circuit terminating Equipment DCT Discrete Cosine Transform DECT Digital Enhanced Cordless Telecommunications (ETSI) DLC Digital Loop Carrier DMT Discrete Multi-tone Carrier DRA Dynamic Rate Adaptation DRR Dynamic Rate Repartitioning DS1 1.544 Mbit/s T1 Interface DSL Digital Subscriber Line DSLAM DSL Access Multiplexer DTE Data Terminal Equipment DTMF Dual Tone Multi Frequency DTR Draft Technical Report EC European Commission EDH Electronic Document Handling EMC ElectroMagnetic Compatibility EN European Norm EOC Embedded Operations Channel ERM ETSI committee on EMC and Radio spectrum Matters ES ETSI Standard ETR ETSI Technical Report ETSI European Telecommunications Standards Institute EU European Union FGS Fine Granularity Scalability FSK Frequency Shift Keying

FTP File Transfer Protocol GSM Global System for Mobile Communications GSTN General Switched Telephone Network (i.e., PSTN) HDLC High level Data Link Control HDSL High-rate Digital Subscriber Line HS Harmonized Standards IAF Internet Aware Fax (T.38) IC Impairment Combination ID Identification IDCT Inverted Discrete Cosine Transform IEC International Electrotechnical Committee IETF Internet Engineering Task Force IMT International Mobile Telecommunications (IMT-2000) IP Internet Protocol IPR Intellectual Property Rights ISDN Integrated Services Digital Network ISO International Organization for Standardization ITAAB ISDN Technical Advisory Ad hoc Board ITAC ITU-T Advisory Committee ITU International Telecommunication Union ITU-T ITU Telecommunications Sector JBIG Joint Binary Image Group JPEG Joint Photographics Expert Group JTC Joint Technical Committee KTA Key Technical Areas LAN Local Area Network LCD Loss of Cell Delineation LDPC Low Density Parity Check LT Line Termination LTU Line Terminating Unit LW Long Wave MC Message Center ME Mobile Equipment Megaco MEdia GAteway Control (IETF) MIB Management Information Base MMUSIC Multiparty Multimedia Session Control MOH Modem on Hold MPEG Motion Picture Experts Group MVC Mobile Video Coder MW Mid Wave NAL Network Adaptation Layer NGDLC Next Generation Digital Loop Carrier NMC Network Model Coverage NTP Network Termination Point NTR Network Timing Reference NTU Network Terminating Unit OAM Operations, Administration, and Maintenance OCG Operational Coordination Group (ETSI) ONP Open Network Provision OSI Open System Interconnection PAR Peak to Average Ratio PCCC Parallel Concatenated Convolutional Codes PCM Pulse Code Modulation PICS Protocol Implementation Conformance Statement PMD Physical Media Dependent layer PMS Physical Media Specific POTS Plain Old Telephone Service PSD Power Spectral Density PSNR Peak Signal to Noise Ratio QAM Quadrature Amplitude Modulation QCIF Quarter CIF QoS Quality of Service QP Quantization Parameter (H.262) R-D Rate Distortion

R&TTE Radio and TTE (Telecommunications Terminal Equipment) Directive RAM Remote Access Multiplexer (DSL Forum) RFC Designation for an IETF Standard RFI Radio Frequency Interference RS Reed-Solomon (code) RT Remote Terminal RTP Real Time Transport Protocol (IETF) SCM Single-Carrier Modulation SDO Standards Development Organization SDP Session Description Protocol SDSL Symmetrical high bit rate Digital Subscriber Line SHDSL Single-line High Speed DSL SIGTRAN SIGnaling TRANsport (IETF) SIP Session Initiation Protocol (IETF) SNMP Simple Network Management Protocol (IETF) SNR Signal to Noise Ratio SPAN Services and Protocols for Advanced Networks (ETSI) SS Steady State SSG Special Study Group (ITU) STM Synchronous Transmission Mode STU SHDSL Transceiver Unit TAAB Technical Ad hoc Advisory Board TB Technical Body TBD To be Determined TBR Technical Basis for Regulation (ETSI standard) TC Technical Committee TC Transmission Convergence Layer TE Terminal Equipment (ETSI Committee) TETRA Trans European Trunked RAdio TIA Telecommunications Industry Association TIPHON Telecommunications and Internet Protocol Harmonization Over Networks (ETSI Project) TM Transmission and Multiplexing (ETSI Committee) TML Test Model TP Test Purposes TPS Transport Protocol Specific TR Technical Report TR Technical Requirements (TIA committee) TRAC Technical Recommendations Application Committee TS Technical Specification TSAG Telecommunication Standardization Advisory Group (ITU) TSB Telecommunications Standardization Board (ITU) TSB Telecommunications Systems Bulletin (TIA) TSS Test Suite Structure TSSC Technical Standards Subcommittee (TIA) TTCM Turbo Trellis Coded Modulation TTCN Tree and Tabular Combined Notation UDP User Datagram Protocol (IETF) UPBO Upstream Power Back-Off VDSL Very high speed DSL VLC Variable Length Codeword VoDSL Voice over DSL VQ Vector Quantization VTU-R VDSL Transceiver Unit - Remote Terminal WG Working Group WI Work Item XID eXchange IDentification xTAAB Advisory Board on Other Access Technologies

The next issue of Communications Standards Review (Vol. 11 #11) is scheduled for December, 2000.

YEAR 2000 STANDARDS COMMITTEE MEETING SCHEDULES AS OF NOVEMBER 20, 2000 Subject to Change without Notice

Committee Date(s) Location Committee Date(s) Location ETSI TM6 #20 Nov 27 - Dec1 Monterey, CA TR-42 Dec 4 - 8 Tampa, FL TR-30 Dec 4 - 8 Scottsdale, AZ DSL Forum Dec 5 - 8 Portland, OR ETSI TIPHON #21 Dec 4 - 8 Kyoto, Japan

YEAR 2001 STANDARDS COMMITTEE MEETING SCHEDULES Subject to Change without Notice Committee Date(s) Location Committee Date(s) Location Q4/15 Rapp. Jan 8 - 12 Clearwater, FL DSL Forum Jun 18 - 22 Oslo, Norway Q6, 7, 21/15 Jan 31 - Feb 2 Geneva, Switzerland TIPHON #23 July 9 - 13 S. Antipolis, France SG15 Feb 5 - 9 Geneva Q4/15 Rapp (prop.) Aug 6 - 10 Italy T1E1 Feb 19 - 23 Costa Mesa, CA T1E1 Aug 20 - 24 Toronto or Montreal TR-41 Feb 19 - 23 Costa Mesa, CA TR-41 Aug 20 - 24 Toronto or Montreal TM6 #21 Feb 26 - Mar 2 S. Antipolis, France TR-42 Aug 20 - 24 Bar Harbor, ME or TR-30 Mar 5 - 9 --- Park City, UT TR42 Mar 5 - 9 Palm Springs or DSL Forum Aug 27 - Sep 1 New Orleans, LA Phoenix TM6 #23 Sep 10 - 14 Prague DSL Forum Mar 12 - 16 Vancouver, BC ETSI AT #4 Sep 24 - 28 S. Antipolis, FR ETSI AT #3 Mar 26 - 30 S. Antipolis, France TR-30 Sep 24 - 28 --- TIPHON #22 Mar 26 - 30 Bethesda, MD Q4/15 Rapp (prop.) Oct 8 - 12 Maine Q4/15 Rapp (prop.) Apr 9 - 13 Cairo, Egypt TIPHON #24 November Cape Town, SA T1E1 May 7 - 11 Orlando, FL T1E1 Nov 5 - 9 San Antonio, TX TR-41 May 7 - 11 Orlando, FL TR-41 Nov 5 - 9 San Antonio, TX TM6 #22 May 14 - 18 Gent, Belgium TR-42 Nov 5 - 9 New Orleans, LA Q4/15 Rapp (prop.) Jun 11 - 15 Southern CA TM6 #24 Nov 12 - 16 S. Antipolis, FR TR-30 Jun 11 - 13 Southern CA TR-30 Dec 3 - 7 --- TR-42 Jun 11 - 15 Montreal or Niagara DSL Forum Dec 3 - 7 Munich, Germany Falls

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Communications Standards Review (ISSN 1064-3907) is published 9 - 10 times per year, within days after the latest, related standards meetings. Editor: Elaine J. Baskin, Ph.D. Technical Editor: Ken Krechmer. Copyright © 2000, Communications Standards Review. All rights reserved. Copying of individual articles for distribution within a subscriber organization is permitted. Subscriptions: $795.00 per year worldwide, paper or electronic format. Corporate Intranet subscriptions (Corporate license for multiple copies) are available. Submit articles for consideration to: Communications Standards Review, 757 Greer Road, Palo Alto, CA 94303-3024 USA. Tel: +1- 650-856-9018. Fax: +1-650-856-6591. e-mail: [email protected]. Web: http://www.csrstds.com.

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November 20, 2000

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