COMMUNICATIONS STANDARDS REVIEW

Volume 6, Number 8 December 1995

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.

TR-29, Facsimile Systems and Equipment, October 16 – 18, 1995, San Diego, CA...... 3 TR-29.1 Facsimile and File Transfer Protocols...... 4 TR-29.2 Facsimile Digital Interfaces...... 7 TR-29.3 Audiographic Conferencing...... 10 TR-29.4 Secure Facsimile...... 10 TR-29 Partial Meeting Roster, October 16 – 18, 1995, San Diego, CA...... 12 The Very Low Bitrate Visual Telephony, October 17 – 20, 1995, Darmstadt, Germany...... 13 Video Coder (H.263)...... 13 Speech Coder (G.723)...... 14 Multiplex (H.223)...... 17 Communication Control (H.245)...... 18 System (H.324)...... 18 Mobile (AV.32M)...... 20 H.263L Future Video Coder...... 22 H.324 Testing...... 22 DTE/DCE Interface...... 23 Non-Conversational Services...... 23 Ad Hoc Committees...... 24 LBC Rapporteur’s Meeting Roster, October 17 – 20, 1995, Darmstadt, Germany...... 25 Experts Group Meeting On G.DSVD, October 23 – 25, 1995, Geneva, Switzerland...... 26 G.DSVD Experts Meeting Roster, October 23 – 25, 1995, Geneva, Switzerland...... 29 TR-30, Data Transmission Systems and Equipment, November 13 – 17, 1995, Orlando, FL...... 30 TR-30.1 Modems...... 30 TR-30.2, Data Transmission...... 32 TR-30.3 Equipment Evaluation and Network Interfaces...... 33 TR-30.4 DTE-DCE Protocols...... 35 TR-30 Meeting Roster, November 13 – 17, 1995, Orlando, FL...... 37 SG 15 Transmission Systems, WP 1 and WP 2, November 14 – 22, 1995, Geneva, Switzerland...... 38 SG 15 WP 1, Audiovisual/Multimedia...... 38 Q3/15 Multimedia Harmonization...... 42 Study Questions for the Next ITU Study Period...... 43 JCG/AVMMS...... 43 SG 15 WP 2, Voice Processing and Operation Function...... 44 SG 15 WP 1 and WP 2 Meeting Roster, November 14 – 22, 1995...... 50 ETSI Terminal Equipment (TE) Plenary Meeting, November 27 – December 1, 1995, Antwerp, Belgium...... 52 Multimedia Management Group (MMG)...... 52 SRC6 Implementation Starter Group...... 52 TE1, Telematic and retrieval services...... 52

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TE2, Telematic Terminals...... 53 TE3, Message Handling System...... 54 TE4, Audiovisual and Voice Terminals...... 54 TE5, Terminal access to public networks...... 55 TE6, Directory Systems...... 56 TE9, Card Terminals...... 56 CEC related matters...... 57 Standards Management...... 57 Liaisons...... 58 Other Highlights...... 59 ETSI TE Plenary Meeting Roster, November 27 – December 1, 1995, Antwerp, Belgium...... 59 Acronym Glossary...... 61 1996 Meeting Schedules as of December 21, 1995...... 63

2 Vol. 6.8 Copyright © CSR 1995 December 1995 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF TR-29, FACSIMILE SYSTEMS AND EQUIPMENT OCTOBER 16 – 18, 1995, SAN DIEGO, CA TIA-536 and TIA-537, US G4 standards, are being balloted for rescission. S. Urban noted that TIA-538 (T.6) is up for renewal. TIA-466-A (US standard equivalent to T.30 as of 1993 with some additions) was ready to be published. TIA-465-A (US standard equivalent to T.4) has been published. S. Urban noted that some concerns had been raised with the ITU test charts because they are slightly wider than 8.5 inches to present the maximum scan line width. He asked if others have had difficulties with the wider dimension. M. Moldovan (Genoa), Testing Editor, has a draft of PN-3194, the TSB on conformity fax testing, at ftp.gentech.com directory pub 3194.doc. H. Silbiger (AT&T) presented TR-29/95-10-49©, Draft Recommendation T.svf, Application Profiles for Simultaneous Voice and Facsimile Terminals (based on V.61), for information. For existing machines that have voice I/O (games machines and standalone fax), no additional standards for the digital interface would be needed.

K. Krechmer (ACTION Consulting) resigned as Secretary of TR-29; J. Rafferty (Human Communications) agreed to take over as secretary. LIAISONS

V. Cancio (Xerox), the new chair of TR-29.2, reported on the TR-29.2 meeting (see full report below). With respect to the MFPI (MultiFunction Peripheral Interface) project, R. Lutz (Cognisys) will review the addition of MLC (Multiple Logical Channel) into IS-650 (MFPI, PN-1906). He will ask Hewlett Packard to submit the MLP (Multi-Layer Protocol) to the next TR-29.2 meeting to determine the status of the IPR (Intellectual Property Rights) issues. Also, additional physical layer interfaces were supported (e.g., USB, serial ports). The issue of Class 3 and the use of job submission was discussed. There was discussion about removing the Class 3 references from T.31 (Class 1) and T.32 (Class 2). This will effectively occur when the US accepts the use of T.31 and T.32 in place of Class 1 and Class 2. K. Krechmer (ACTION Consulting) presented draft T.610, TR-29.2/95-10-52 (R. Goldstein, Q1/8 Rapporteur), which is an overview of T.611. K. Krechmer noted the direction of the T.610 work to include voice and related near real time operation. He indicated the desire to see the work in T.611 included in future job submission efforts. S. Urban (Delta Information Systems) noted that work is progressing in ISO/IEC JTC1 WG1 SC29 on near lossless JBIG (Joint Binary Image Group) and JPEG (Joint Photographics Expert Group) compression. These algorithms can be tuned to select a compression ratio relative to the coding loss. Also, a new algorithm, pattern matching, (PA-37 [H.R. Silbiger, TR-29] from September 1995 Q5/8 and Q19/8 Rapporteurs meeting) from AT&T offers slightly lossy bi-level compression when used for character oriented documents. J. Rafferty reported on the post dialing delay work at the September 1995 Q5/8 meeting. He noted that there was interest developing in a Tx timer focused on network delay timing, separate from the T1 timer. S. Urban (Delta Information Systems) reported that work on Quality of Service (QoS) in SG 2 and SG 15 is continuing. He has seen outlines of work (2 pages) on network fax performance issues. J. Rafferty (Human Communications) noted that ECM (Error Correction Mode) use with 64 octet frame size could eliminate some of the QoS issues raised. In Annex C of T.30, 64 octet frame size is to be supported via DIS/DTC bit 7. The US version of T.30 uses bit 28. TR-29 supported S. Urban drafting a white contribution supporting the use of bit 7 for all. ITU ORGANIZATION

S. Perschau (NCS) introduced TR-29/95-10-48. It includes seven documents from the Technical Standards Advisory Group (TSAG) meeting (September 19-22 in Geneva) relating to the proposed future operation of the ITU. TR-29/95-10-48 part 1 proposes changes to Study Group working methods: • More rapid action on amendments to Recommendations • Deleting a question that does not receive any contributions for two successive meetings (previously Questions were only deleted at the end of a study period). Any comments should be addressed to the TSAG by October 1996.

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TR-29/95-10-48 part 4 describes the possible organization of a Audiovisual/Multimedia Services Study Group made up of parts of existing SG 8, SG 14, and SG 15, as well as SG 1 and SG 9. Such a reorganization could commence with the WTSC (World Standardization Conference) October 1996 meeting. TR-29/95-10-48 part 6 describes possible new directions for the ITU-T using post 1996 Task Forces (TFs). The idea put forth is to support TFs to focus on specific applications areas and generate as output either Requests for Comments or Task Force Reports as opposed to Recommendations. Recommendations would continue to be produced by the Study Groups. TR-29/95-10-48 part 3 (Canada) discusses the future role of Joint Coordination Groups (JCGs) noting that the five JCGs in operation have not minimized overlapping work in Study Groups but contributed to it. TR-29/95- 10-48 part 7, a report on the future disposition of JCGs by the subworking group of the TSAG, suggests reducing the future activities of any JCG (Joint Coordination Group) to coordination. TR-29.2 P ROPOSED CONTRIBUTIONS TO SG 8

TR-29.2/95-10-55 (Microsoft) was presented by V. Cancio (Xerox) as a proposed White Contribution. It proposes that the US support draft Annex A/V.25ter and not continue with the parallel work in draft Annex C/T.31. This was supported. TR-29/95-10-47 (J. Rafferty, Human Communications) proposes changing the FCLASS indicator in amendments to T.32 (planned for February 1996) to a value of 2.1. This leaves 2.0 for use by the existing version of TIA-592 (assuming no versions of T.32 emerge before February 1996). J. Rafferty proposed bringing this forward a White Contribution and then bringing, as a default document, the change pages of T.32. S. Urban (Delta Information Systems) will also bring to US ITU Study Group D the previously approved paper on BFT (Binary File Transfer), supporting a modification to the Application Reference to allow Object ID as well as a graphic string (see CSR-T Vol. 6.6 page 35 BFT). Ken Krechmer, Communications Standards Review

TR-29.1 FACSIMILE AND FILE TRANSFER PROTOCOLS TR-29.1 focused on modifications to T.4 and T.30, including modifications for support of V.34. The other major area of work was on enhanced negotiations. Applications of enhanced negotiations included enhanced BFT. J. Rafferty (Human Communications) was supported unanimously as Vice Chair of TR-29.1. Liaison with the Salutation Consortium has been started. This group has a limited interest in fax. The work is being driven from Japan. They want a return receipt facility and generally want to use a simplified facsimile en- hancement approach as outlined in R. Lutz’s paper on negotiations for the job submission application. They may also use NSF (Non Standard Facilities) frames or Binary File Transfer. J. Rafferty noted that he had sent an informal message to Mr. Satoh (on the technical committee for this group). TR-29.1 agreed to send them a message inviting them to work cooperatively with TR-29.1. LIAISON REPORTS

G. Griffith (Rockwell) reported the results related to V.34 fax at the September Q19/8 Rapporteurs meeting in Palo Alto, CA. A. Pugh (MGUK Ltd.), T.30 Editor, submitted two white contributions at the meeting which summarize amendments to T.4 and T.30. T.4 and T.30 are up for approval in February. Various modifications were agreed to and will be submitted by A. Pugh as white papers. J. Rafferty reported on portions of the Q5/8 Rapporteurs meeting. Q5/8 has now agreed that the New Fax Negotiations Method will go forward and that a consolidated permanent document needs to be developed in the form of draft amendments. A migration path has been agreed to, such that new services shall be evaluated to see if they will be added to the current method as well as to the new method. H. Silbiger (AT&T) reported on the submission of a Simultaneous Voice and Fax paper from AT&T which was accepted as the basis for future work. This submission was also reviewed by the Q1/14 meeting, which agreed to continue liaison with SG 8 on this issue. A contribution was requested by Q5/8 on the use of a 64 octet ECM (Error Correction Mode) frame for T.30. The capability to request use of a 64 octet frame for Group 3 Annex C operations is included in the current white papers from A. Pugh, T.30 Editor.

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H. Silbiger also reported that a joint meeting of Questions 8 and 15 was ongoing during the same week in Barcelona. The BFT proposal from the US on incorporation of Object IDs in the application reference field of T.434 was scheduled to be discussed at that meeting. G. Griffith (Rockwell) reported that the Q1/14 Working Party meeting held in Munich during the prior week had “determined” the latest changes to V.34 and V.8 that were requested by Q19/8. British Telecom proposed that V.8 be modified to support V.8bis functionality. However, an ad hoc meeting at Q1/14 agreed to add the V.8 functionality to V.8bis. Several recommendations related to simultaneous voice/data have been determined. SG 15 is studying the voice coders to be used for DSVD (Digital Simultaneous Voice Data). The two methods still under consideration are from the DSP Group (TrueSpeech) and University of Sherbrooke. Technical Editor’s Note: SG 15, at the November meeting, selected the University of Sherbrooke coder. See the report of that meeting in this issue of CSR-T. EXTENDED NEGOTIATIONS

TR-29.1/95-10-48© (R. Lutz, MFP Association) is a technical contribution regarding job submission and Transportable Document Format (TDF). It outlines a methodology for handling job submission including a TDF that is suitable for use in the process of negotiating with the service of interest (whether that service is Direct Connect, Local Area, or Dial-Up) and passing arbitrary file information. Figure 1 of the document provides a model for General Device Abstraction. Section 4.5 reviews the key issue of Configuration. Many definitions are provided to address various different methodologies such as MIBs (Management Information Bases), MIFs (Management Information Files) and various forms of Configuration Management. R Lutz also referenced TR-29.1/95-10-50 (R. Lutz, MFP Association) which contains RFC-1759, the Printer MIB (Management Information Base). Section 4.9.1 of TR-29.1/95-10-48© defines a Job, which is a logical grouping of tasks scheduled at the same approximate time. Section 7.1 defines a “Transportable Document Format” composed of elements which include a job ticket, specification, content descriptor, and content. R. Lutz proposed that the content descriptor be T.434 compatible. A series of steps were reviewed that make up the Job Management process. This process basically involves establishing connections between service providers, exchanging capabilities, and then transferring data content. Provisions were also made to provide reports on events and status. TR-29.1/95-10-49 (R. Lutz, MFP Association) contains version 2 of advanced facsimile negotiation requirements for MFPs (MultiFunction Peripherals) and dial-up job submissions. It provides a list of applications needs and a proposal for an alternative form of advanced negotiations that differs slightly from the goals of the current proposal. It also provides a list of goals that the new negotiations method should address. It lays out different ways to do the Job Submission approach using conventional T.30 and also using Annex C (duplex). The basic concept is that all of the large amounts of data involved would be transmitted using a fax ECM mode. It was noted during discussion that Binary File Transfer or Basic File Transfer could be used to do this. Some technical questions were raised on the approach for doing job submission on “legacy” fax devices. For example, many current fax machines will only permit one turnaround in a fax session; the paper suggests that several turnarounds be initiated using the EOM (End of Message) signal in order to transfer job submission data in alternate directions during the same session. R. Lutz noted that several Japanese vendors in the Salutation Consortium requested that there be a way to do job submission which would only require a firmware upgrade for fax devices in a current style. There was some agreement that establishing a backward compatibility mode for compatibility with the current style of T.30 terminals has merit. However, there was concern about suggestions to restrict the addition of new capabilities to the protocol based on what existing “gateways” or DCME/PCME (Digital Circuit Multiplication Equipment/ Packet Circuit Multiplication Equipment) can handle, particularly concerning the suggestion that no new fax signals be permitted for use in the backward compatibility. It was noted that previously standardized T.30 signals (e.g., for ECM or BFT) are just now showing up in the marketplace. R. Lutz also proposed principles for job submission using an advanced method that can take advantage of next generation duplex fax features. This proposal included the following key points: (1) Use multiple pass negotiations, and (2) maintain a layer separation between the negotiation protocol and the parameters to be negotiated. D. Duehren (Brooktrout Technology, TR-29.1 chair) asked J. Rafferty to summarized the action items that he envisioned were needed to move the new negotiations work forward in the ITU. J. Rafferty outlined the following steps: • Prepare a “permanent document” for the January TR-29.1 meeting for review and submission to SG 8. It will include draft text for amendments to T.30 based upon previous contributions and also include background material and examples. • Prepare amendments as needed to enhance the permanent document. • Explore new applications and how they may fit in with the new negotiations method.

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D. Duehren felt that the preparation of the “permanent document” was important, since this had been requested by Q5/8. He also proposed that several applications of extended fax negotiations can be explored: (1) Job Submission, (2) Security, (3) Selective Polling and Database Retrieval, and (4) Routing. Additional contributions were invited in all of these areas. J. Rafferty prepared a project statement for an Extended Group 3 Facsimile Negotiations project (TR-29.1/95-10- 56). The project will focus on the preparation of contributions to the ITU on extensions to the Group 3 facsimile protocol. The proposed scope was accepted, and the project will be submitted to TIA for a project number. J. Rafferty has agreed to be the editor for the project. PN-3599 FAX ROUTING

The PN-3599 Editor, J. Rafferty, proposed that the IS-141 (Routing of Group 3 Facsimile Messages Utilizing the Subaddress) interim standard for facsimile routing be re-affirmed while awaiting the approval of T.routing in Study Group 8. The members voted to re-affirm it. He also reviewed the results of a TR-29 contribution on a variable length SUB (Subaddress) at the interim meeting of Question 5 of SG 8. There was interest in this approach, but it was suggested that a more complete solution be developed, which may include a length indicator, the application of variable length FIFs (File Interchange Format) to the SUB, SEP (Selective Polling), and FIF frames, and support for alphanumeric data. Further contributions are invited. J. Rafferty also reported on a TR-29 contribution in which the subaddress was proposed for use in polling. This was also well received, but further contributions are needed. V.34 FAX

G. Griffith (Rockwell) presented four papers for information. TR-29.1/95-10-52 (A. Pugh, Editor, UK) is Draft Amendment 3 to Recommendation T.4. It was submitted as an ITU-T white contribution by the T.4/T.30 Editor, A. Pugh. It is a very short paper that modifies T.4 to add V.34 modulation and delete the V.33 method. TR- 29.1/95-10-53 (A. Pugh, Editor, UK) is Draft Amendment 3 to Recommendation T.30. It contains changes that 1) incorporate the use of the modulation system defined in Recommendation V.34, 2) indicate the phasing out of the modulation system defined in Recommendation V.33, and 3) cover the use of network-oriented codes to be specified in revised Recommendation T.35. Both of the papers are based upon decisions that were made at the March 1995 SG 8 meeting. The amendments were “determined” at that time. TR-29.1/95-10-54 (A. Pugh, Rec. T.30 Editor) contains proposed amendments to Recommendation T.30 to incorporate the deletion of references to Groups 1 and 2 and the inclusion of the V.34 modulation system. It is based upon decisions that were made at the September Q5/8 and Q19/8 Rapporteurs meeting in Palo Alto. The paper includes text and charts which revise and supplement TR- 29.1/95-10-53, and it includes edits to a revised annex F.4 which itemizes changes needed within the V.34 and V.8 recommendations to support Group 3 fax. TR-29.1/95-10-55 is a collection of e-mail conducted between A. Pugh and T. Mori (Japan) that contains suggested clarifications to the material in the working draft. It is expected that A. Pugh will incorporate clarifications from TR-29.1/95-10-55 into TR-29.1/95-10-54 and then submit the material as a white contribution. Collectively, the three white contributions will contain the amendments to T.4 and T.30 that are proposed for approval at the February 1996 meeting of Study Group 8. Members were encouraged to review the papers and note any editorial changes that may need to be addressed. PN-3364 ENHANCED BINARY FILE TRANSFER

TR-29.1/95-10-44 (J. Rafferty, Human Communications) contains excerpts from T.127, Multi-Point Binary File Transfer, which addresses the approach taken in requesting Binary File Transfers by TR-29.3 (audiographics conferencing). T.127 is an approved ITU-T recommendation for transferring data in a multi-point conferencing environment. Like Group 3 fax, T.127 uses the BFT format which has been standardized as ITU-T T.434. J. Raf- ferty felt that the paper had some useful ideas on BFT negotiations that could possibly be adopted for use with enhanced BFT negotiations in Group 3 fax. In particular, he drew attention to: (1) the exchange of a subset of BFT tags prior to the file transfer, and (2) the ability to negotiate a compression method in advance of the transfer which could be applied to the entire data stream, including BFT header fields. No action was taken, but TR-29.1 has interest in developing an enhanced BFT negotiations method for use in Group 3. TR-29.1/95-10-45 (J. Rafferty, Human Communications) contains the most current list of Object IDs that have been registered by the Electronic Messaging Association (EMA) and various software companies for use with the Application Reference tag for X.400 File Transfer Body Part (FTBP) use. The list was provided for information in association with the work to extend T.434 BFT and related protocol negotiations. J. Rafferty noted that some of the IDs were being revised and that other additional IDs were under consideration. These OIDs (Object IDentifiers) tie

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into TR-29.1/95-08-31 (J. Rafferty and H. Silbiger) and was approved by TR-29.1 at the last meeting. TR-29.1/95- 08-31 proposed adding the OID to the syntax of the T.434 Application Reference field. TR-29.1/95-10-58 (D. Duehren, Brooktrout) is the current list of BFT Diagnostic Messages as approved by the ITU-T for T.434 in March. TR-29.1 agreed to support sending TIA-614, BFT Format for Group 3 Facsimile (SP- 2225), with editorial changes to include the diagnostic messages, to the TIA TSSC (Technical Standards Subcommittee) for publication. H. Silbiger noted that there had been an inquiry from T. Mori (Ricoh, Japan) about the formatting of the FDM (Frequency Division ) frame in T.30. There was a limited description of FDM in T.30. Contributions were invited. R. Lutz volunteered to be editor for the enhanced BFT project, PN-3364. The project will deal with enhancements to BFT including negotiations. FAX SECURITY

S. Urban (Delta Information Systems, TR-29 Chair) presented TR-29.1/95-10-51 (Ad Hoc Group on Security) which contains implementation considerations for secure facsimile within G3 and G4. The Ad Hoc Group concluded the following: • Both RSA (Public Key Cryptosystem invented by Rivest, Shamir, and Adleman) and HKM (Hawthorne Key Management) could meet the necessary service requirements. • HFX (Hawthorne Facsimile Cipher), FEAL32 (Fast Encryption ALgorithm 32), and SAFER (Secure and Fast Encryption Routine) cipher are acceptable. • A minimum possible number of alternative key management, cipher, and hashing systems should be recommended by SG 8. • SG 8 should recommend a default system for each of key management, ciphers, and hashing; all systems supporting ITU fax security should implement these defaults. • Manufacturers should be free to implement any additional systems recommended by the ITU for fax security. • Further work should be done on HKM/HFX and RSA proposals so that a final decision on the default systems can be made in February 1996. S. Urban noted that the issue of registration authorities was still not really resolved. Another issue is how keys will be exchanged to begin the security process. There are two ad hoc groups in Q5/8 that will be preparing proposals for a security framework within Group 3 for review in February. The groups include advocates for the RSA and HKM methods of encryption. S. Urban volunteered to be editor for a new TR-29.1 project on security; he will prepare a project statement. OTHER HIGHLIGHTS

TR-29.1/95-10-46 (UK, same as PA-43 presented at the Palo Alto Rapporteurs meeting) proposes the addition of some new signals to Recommendation T.30 to enable several documents to be retrieved with the same call using the Selective Polling Frame (SEP). TR-29.1/95-10-47 (UK, same as PA-44), presented at the Palo Alto Rapporteurs meeting, proposes the definition of new responses in Recommendation T.30 to invalid or corrupted reception of frames for Password (PWD), SEP, and Subaddressing (SUB) in order to provide more efficient handling of these events. James Rafferty, Human Communications

TR-29.2 FACSIMILE DIGITAL INTERFACES V. Cancio (Xerox) was nominated and unanimously approved as the new TR-29.2 Chair. A volunteer to serve as Vice Chair was requested. R. Lutz (Cognisys and MFPA) offered to serve and was unanimously accepted. J. Decuir (Microsoft, outgoing TR-29.2 Chair) distributed TR-29.2/95-10-42, the status of committee business. The results of discussion are reported in the applicable sections below. It was agreed to have Class 4 updated (editor: L. Staples, Data Race) and consider how to make Class 4 an optional capability under Class 1 (using Class 1 commands and responses with Class 4 for transparency).

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LIAISON REPORTS

TR-30.4 DTE-DCE Protocols J. Decuir reported on the September TR-30-4 meeting. TR-30.4 generated US contributions to ITU Q7/14, including draft Annexes for V.25ter that overlap the draft Annexes for T.31, as described in TR-29.2/95-10-46 (J. Decuir, Microsoft). ITU Q5/8, Group 3 Equipment J. Decuir presented TR-29.2/95-10-43, reporting on the parts of the September Q5/8 Rapporteur’s meeting concerning T.31 and T.32. Agreements were reached for Resolution 1 decision at the February SG 8 meeting on the texts for: • TR-29.2/95-10-44 (J. Decuir, Rec. T.31 Editor), Amendment 1 to T.31 (same as PA-76) • TR-29.2/95-10-45 (J. Decuir, Rec. T.32 Editor), Amendment 1 to T.32 (same as PA-77) A liaison was sent to the SG 14 WP1 meeting containing T.31 Amendment 1. ITU Q7/14 DTE-DCE CONTROL

TR-29.2/95-10-46 (J. Decuir, Microsoft) reports on the parts of the October Q7/14 Rapporteur’s meeting concerning V.25ter amendments. Agreements were reached for Resolution 1 decision at the March SG 14 meeting on the texts for: • Amendment 1 to V.25ter, Annex A (see TR-29.2/95-10-47), including extensions for V.8bis • V.ib, In-Band DCE control, an extension of TIA-617 to support 8-bit in-band codes • Synchronous Data Modes, previously draft Annex B/V.25ter, as Annex A/V.ib, TR-29.2/95-10-50 (J. Decuir, V.25ter Editor) TR-29.2/95-10-47 (Q7/14) is a liaison that was sent back to the SG 8 meeting containing V.25ter Amendment 1. AMENDMENTS TO ITU T.31 FOR V.34

As noted above, the changes from the March version of T.31 are contained in TR-29.2/95-10-44 (J. Decuir, Rec. T.31 Editor). It was agreed for Resolution 1 decision for the February 1996 SG 8 meeting.

TR-29.2/95-10-55, (J. Decuir, Microsoft) proposes that the US support dropping Annex C/T.31 in favor of Annex A/V.25ter. The basis is that SG 14 was requested to take over the work of Annex A/V.25ter, it was done, and it is an improvement over the original SG 8 work. The contribution was approved for forwarding through TR- 29 and US Study Group D as a US position to SG 8. J. Decuir noted that it would be appropriate for TR-29.2 to study TR-29.2/95-10-50, Revised Annex B/V.25ter (J. Decuir, V.25ter Editor), and consider drafting a simplified Annex B/T.31 to reference it. However, there was in- sufficient time at the meeting to do so. Contributions were invited. AMENDMENTS TO ITU T.32 FOR V.34

As noted above, the changes from the March version of T.32 are contained in TR-29.2/95-10-45 (J. Decuir, Rec. T.32 Editor). It was agreed for Resolution 1 decision for the February 1996 SG 8 meeting. No changes were considered necessary. No action was taken. PN-3130 SERVICE CLASS 4

The new editor, L. Staples (Data Race), asked for help recovering a usable machine-readable version of the last draft of PN-3130. J. Decuir provided one based upon an RTF file provided by the previous editor. The Editor asked what problem PN-3130 was needed to solve. Members recapitulated previous discussions and noted that Facsimile DTE (Data Terminal Equipment) software manufacturers had asked for it. In discussion, it was proposed that PN-3130 might be simplified by defining some switch (e.g., +FCLASS=4) that would cause the DCE (Data Circuit Terminating Equipment) to use Class 4 operating procedures (queuing of com- mands and responses) but also using TIA-578/T.31 commands and responses rather than new ones. There was support for this idea, and contributions were invited.

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PN-3294 FACSIMILE DCE APPLICATIONS NOTES

There were no new contributions. It was suggested and agreed that PN-3294 should include a section explaining the relationships amongst the various versions of Class 1 and Class 2. PN-3626 REVISION OF TIA-578-A (C LASS 1)

J. Decuir, Editor of TIA-578-A and T.31, presented the following two contributions. TR-29.2/95-10-54 is the ANSI project initiation request, using text agreed upon at the previous meeting. TR-29.2/95-10-48 (J. Decuir, Rec. T.31 Editor) is a first draft of PN-3626 containing new material spliced in from T.31 and T.31 Annex B. The cover page listing the changes was discussed in detail. During discussion, several options for progressing PN-3626 were proposed: • Stitch revisions from T.31 into TIA-578-A to make TIA-578-B, as shown in TR-29.2/95-10-48 • Adopt T.31 as the new basis, and then add an informative Annex which describes the differences from TIA-578-A • Do nothing TR-29.2 agreed to the second option above and decided that this would be within the scope of the agreed-upon project statement in TR-29.2/95-10-54. J. Decuir agreed to collaborate with the new editor, V. Cancio (Xerox), to generate a contribution on the differences, beyond that provided in TR-29.2/95-10-48. PN-3625 REVISION OF TIA-592

J. Decuir, Editor of TIA-592 and T.32, presented the following two contributions. TR-29.2/95-10-53 is the ANSI project initiation request, using text agreed upon at the previous meeting. TR-29.2/95-10-49 is a first draft of PN-3625, containing new material spliced in from IS-134 (Revision to TIA/EIA-592, Asynchronous Facsimile DCE Control Standard Service Class 2-A), T.32, and T.32 Annex C. The cover page listing the changes was discussed in detail. TR-29.2 agreed to the same approach as decided above: that TIA would adopt amended T.32 and then describe the differences from TIA-592. J. Decuir again offered to collaborate with V. Cancio to generate a contribution on those differences. PN-3625 will result in the replacement of IS-134. However, since it expires shortly, TR-29.2 agreed to ask TIA to renew it for a year. It was also noted that this approach of basing TIA-592-A directly on T.32 will also retire TIA-605 (DCE to local DTE Packet Protocol), since it is included in T.32 section 9. MFP R. Lutz (Cognisys, representing MFP Association) presented TR-29.2/95-10-51, a report on the status of MFPI work. It provides the status of IS-650 (MFPI), addresses cooperation with IEEE-1284.3, and discusses the future of other layers, including PN-2725 Class 3. IS-650 COMPLETION

The log jam over intellectual property disclosures was broken at TIA. With some editorial changes (previously agreed), IS-650 has been released for publication. FUTURE MFPI

Since MFPI work has been completed, the IEEE 1284.3 committee is progressing work on interfaces over common parallel ports. Hewlett Packard contributed their MLC specification, embedded in many shipping products, for con- sideration by IEEE 1284.3. MLC has been endorsed by the MFPA (MFP Association). Based on these facts, R. Lutz proposed that future MFPI be revised to use MLC with 1284.3 devices. His proposed plan, from TR-29.2/95-10-51, is as follows: • List requirements for MFP that are not already included in MLC and the work of IEEE 1284.3 • Provide this list of requirements to IEEE 1284.3 to determine which items from the list could/should be accepted for inclusion in the IEEE 1284.3 standard • Include any remaining items in TIA-650 (IS-650 rev 2) • TIA-650 could also include specifications on how to use other interfaces (e.g., serial, Universal Serial Bus, etc.)

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Some support was expressed for this plan, but no decisions were made. R. Lutz indicated that at the MFPA meeting later this week, work would continue on listing requirements. The result may be taken to the IEEE 1284.3 meeting the following week, and answers may be obtained for which items could/should be accepted for the IEEE 1284.3 standard. The Chair, V. Cancio, asked about the intellectual property status of MLC. It was noted that IEEE and ANSI have similar IP policies, and there is presumption that Hewlett Packard’s quoted willingness to provide free licenses to MLC for use with IEEE 1284.3 would also apply to their use with MFPI. She requested a written statement on the intellectual property status of MLC with regard to IS-650. PN-2725 SERVICE CLASS 3

R. Lutz, Editor, proposed that the Job Submission standard, the recently agreed basis of PN-2725, should support interworking with remote MFP terminals or local devices. He proposed that the method determined for working with remote devices be based on T.434. This approach is described in TR-29.1/95-10-48© (R. Lutz, MFP Association). On request, this contribution was renumbered TR-29.2/95-10-56© and distributed in TR-29.2 also. The Editor proposed that job submission be done in steps: • Determine how to do job submission to a far end terminal (e.g., “DUD”) • Determine how to migrate that protocol to a local device • The result would be PN-2725 There was considerable discussion, particularly on the API (Application Programming Interface) aspects of this work. There was some support for the approach, but no conclusion. The Chair noted the need to consider the Computer Fax Protocol. It was noted that job submission API is addressed by T.611. TR-29.2 confirmed its previous consensus that the job submission work is within the scope of PN-2725. However, they agreed to remove references to it in TIA-578-B and TIA-592-A, but this will happen as a side effect of adopting T.31 and T.32 verbatim. CONFIGURATION MANAGEMENT FOR FACSIMILE DEVICES

There were no contributions, nor was there a volunteer to serve as editor. Therefore, the previously agreed project statement (TR-29.2/95-08-33) will not be forwarded to TIA yet. It was noted that T.611 also addresses facsimile configuration. FAX API S

K. Krechmer, ACTION Consulting, presented TR-29.2/95-10-52 (R. Goldstein, Q1/8 Rapporteur), an overview of T.611. Discussion noted that T.611 includes job submission and configuration management. It also has scope beyond those items. R. Lutz proposed that TR-29.2 continue to work in MFPA on job submission (PN-2725) and the future of MFPI, including scope for fax, printing, and scanning. Results will come back to TIA, where work on fax is done. This offer of work from MFPA was welcomed by the committee. Joe Decuir, Microsoft Corporation

TR-29.3 AUDIOGRAPHIC CONFERENCING TR-29.3 met in conjunction with the Q10/8 meeting in Paris, October 2-6, 1995. Please see the Q10/8 report in CSR-T 6.7, October-November, 1995.

TR-29.4 SECURE FACSIMILE

64 KBIT/S STRATEGIC SECURE FACSIMILE

Group 3/64 Option There is Government interest with the objective of using commercial standards wherever possible, as well as NATO interest, in using the new Group 3/64 or G3C standard described in Annex C of T.30. TR-29.4 is not aware of any vendors who have implemented G3C and the Japanese manufacturers are still pushing the Group 4 standard. DoD

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does not have any money to put out a tender for a quantity of G3C compatible units to encourage vendors to im- plement the protocol. No further action will be taken by TR-29.4 until G3C is available from one or more of the facsimile manufacturers. MIL-STD-188-161D Option One approach is to speed up the MIL-STD-188-161D protocol to operate at 64 kbit/s which may be useful for tactical applications and some strategic applications. Depending on the application, FEC may only be needed up to 16 kbit/s and higher resolutions may be desirable. JITC has already done testing on one vendor’s equipment which was able to operate using the MIL-STD at a rate slightly above 40 kbit/s. A speeded up 161D protocol has the advantage of maintaining only one protocol and the definition and testing required can be done relatively easily. G. Constantinou (DoD) agreed that TR-29.4 should concentrate on this option so that at least an interim solution can be formulated. SECFAX 95-10-15 (J. Hamadani, Ricoh) and SECFAX 95-10-16 (N. Wiseman, GTE Government Systems) indicate that there is nothing in the protocol to prevent operation at 64 kbit/s; however, without changes, no perfor- mance improvement such as faster throughput will be achieved. With the flexibility built into 161D, timing parameters can be changed and compression added in order to reduce document transmission times assuming memory- to-memory operation. In SECFAX 95-10-15 three options are presented to support 64kbit/s operation. Although Alternative #2, change one timing for 64kbit/s operation, in the contribution was initially favored, after further discussions it was decided to pursue Alternative #3, change all timings. The timings in all levels of the protocol will be revised, although the core of the protocol is not changed. It was noted that the timing changes proposed in Alternative #3 can be made and initially tested at 16 kbit/s. Changes to the handshake and protocol, plus alternative error schemes, could also be investigated, but it was agreed that these areas add complexity and will be considered in a later phase of the project. B. Bradley (GKI) agreed within the next few weeks to supply comments on the approach based on his company’s experience in operating at bit rates above 16 kbit/s. J. Hamadani will do further study on Alternative #3 and then will prepare a document to include adding a bit in 161D for adding faster response times. The initial assumptions are: memory-to-memory operation; error free transmission lines (It is assumed that 161D’s FEC scheme will not be appropriate to handle errors at 64 kbit/s.); and zero fill bits. Initial testing will be done at 16 kbit/s. J. Tomko (JITC) indicated that JITC could do the testing at a cost which would probably not exceed $10K. G. Constantinou will interface with the government working group and NATO, and also will see if the government might have any money to cover the testing costs. G. Constantinou did not have any other secure fax capabilities that had been presented to him from the working group as a result of the seminar held in June. STU-STE PROGRAM UPDATE

Several questions were raised during the last TR-29.4 meeting and this one regarding the STE (Secure Terminal Equipment) program: 1. What is the specification for the data port interface? 2. Can the STE operate in clear data mode at 64 kbit/s? 3. How is the ISDN interface implemented? With a PCMCIA card? 4. Does the STE program group want secure fax units with PCMCIA card slots which can accept an NSA card for transmission of classified documents? G. Constantinou indicated that GTE is chairing the interoperability working group for the STE and that the data port hasn’t been defined yet. J. Tomko said he would collect all the current information from Motorola on the STE program and circulate it to TR-29.4. A STE working group meeting is being held in the Washington D.C. area in December and TR-29.4 committee members are invited to attend. G. Constantinou will provide the dates. If useful, TR-29.4 could prepare a list of questions with interface parameters that need to be identified. JITC TESTING

The Ricoh Secure Fax Adapter and GKI Rugged facsimile are being tested. The Zenith/Inteq controller which has been tested is being submitted to NATO to obtain a certification letter for STANAG 5000 (reference: SECFAX 95-09-13 from J. Tomko). Once this is accomplished, J. Tomko will submit the other 161-certified equipment to NATO for STANAG 5000 certification. From now on, JITC programs must be fully self-sustaining. The impact of this statement is uncertain, but it may have an effect on pricing for future testing.

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LOSS OF SYNC SIGNAL

G. Constantinou is preparing to submit an Information Paper which recommends that the technical requirement for a loss of sync signal and circuit be investigated, and that if no justification is found, both will be deleted from MIL- STD-188-161 and STANAG 5000. If Paragraph 5.2.4 of the MIL-STD must remain in force, J. Tomko will recommend a minimum time for reply to substitute for the current text which specifies “sufficiently long.” STANAG 5000 LIAISON UPDATE

The STANAG 5000 working group will make multi-page mandatory. The final draft STANAG 5000 (Revision 3) should be balloted by NATO countries starting sometime in February 1996. The requirement for a one meter document capability will be an option. G. Constantinou is preparing a new draft and will resubmit it to the working group.

FACSIMILE PRIVACY AND TR-29.1 LIAISON

It was decided that TR-29.1 would take over responsibility for the commercial uses of fax security. TR-29.4 will continue to monitor events in the commercial security area and establish a liaison with TR-29.1. A paper was distributed in the TR-29 meeting indicating that ITU Study Group 8 has an Ad Hoc group to investigate proposals for secure fax for G3 and G4 using the RSA and/or HKM/HFX (U.K.) systems. The necessary service requirements are: • Mutual authentication • Secure exchange of keys/secret session key establishment • Message confidentiality (encryption) • Message integrity • Confirmation of message receipt It was agreed that SG 8 should recommend a default system for each capability required: key management, ciphers and hashing, and that all systems supporting ITU fax security should implement these defaults. The objective is to make a final decision on the default systems in February 1996. Non-repudiation was not required though confirmation of receipt was very desirable. RSA indicated to the Ad Hoc group that it was offering a new cipher system, RC5, that was acceptable under US export requirements. RSA also felt that NSA might be ready to relax its attitude on the length of encryption ciphers with 44 bits becoming acceptable soon and 48 bits possible in the near future. There was also the possibility that NSA would not object to systems where the number of bits in- creased by approximately two per year from then onwards. Bob Robinson, Ilex Systems

TR-29 PARTIAL MEETING ROSTER, OCTOBER 16 – 18, 1995, SAN DIEGO, CA Stephen Urban, Delta Information Systems Chair TR-29 David Duehren, Brooktrout Technology Chair TR-29.1 Vivian Cancio, Xerox Chair TR-29.2 Bruce DeGrasse, BJ Communications Chair TR-29.3 Bob Robinson, Ilex Systems Chair TR-29.4 ACTION Consulting Ken Krechmer Hewlett Packard Salvador Plasencia AT&T Herman Silbiger Human Comm. James Rafferty AT&T Paradyne Robert Lastinger JITC Jim Tomko Cognisys Raymond Lutz Lanier Worldwide Jim Dahmen Comm. Stds Review Elaine Baskin Microsoft Joe Decuir DoD/DISA-JIEO George Constantinou NCS Stephen Perschau Datarace Les Staples Ricoh Corporation James Hamadani Gammalink Michael Spann Rockwell Int’l Glen Griffith GKI Brad Bradley (via phone) Texas Instruments Henry Jacobs GTE Gov’t. Systems Neil Wiseman Xerox Vivian Cancio

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REPORT OF THE VERY LOW BITRATE VISUAL TELEPHONY RAPPORTEUR’S MEETING (QUESTION 2/15) OCTOBER 17 – 20, 1995, DARMSTADT, GERMANY TD-1 is the list of attendees. TD-2 is the list of documents. The October meeting of the ITU-T Experts Group for Very Low Bit Rate Visual Telephony was organized into the following segments: • Video Coder (H.263) • Speech Coder (G.723) • Multiplex (H.223) • Communication Control (H.245) • System (H.324) • Mobile (AV.32M) • H.263L • H.324 Testing • Non-Conversational Services One major purpose of this meeting was to finalize the edits on the five draft Recommendations (H.324-System, H.263-Video, G.723-Speech, H.245-Control, H.223-Multiplex) that were determined at the February SG 15 meeting and submitted to the ITU as White Documents in July. The resulting changes to these Recommendations are electronically available at the following FTP site: ftp://ftp.std.com/vendors/ PictureTel/h324. Another major objective of this meeting was work toward the development of the AV.324M multimedia terminal. The Rapporteur, R. Schaphorst (Delta Information Systems), presented document LBC-95-264 regarding Intellectual Property Rights (IPR) for the H.324 Recommendations. FT/CNET/ University of Sherbrooke, DSP Group/Audio Codes, National , Sharp, Siemens, Telenor and Thomson provided IPR statements. The attention of the members was also drawn to a request made by the TSB (Telecommunications Standardization Board) that “Any ITU member organization aware of a patent held by itself or others which may fully or partly cover elements of the draft Recommendation(s) proposed for approval is requested to disclose such information to the TSB, in no case later than the date scheduled for approval of the Recommendation(s), in accordance with TSB patent policy.” VIDEO CODER (H.263) The Chair of this work was K. Rijkse (KPN Research). DRAFT RECOMMENDATION H.263

Draft Recommendation H.263, contained in LBC-95-251, was reviewed; and the changes that were introduced since the last meeting were approved. Additional editorial changes were proposed and accepted, and some additional sentences were added to clarify and improve the consistency of the recommendation. A few changes were expected to be made after the meeting. A small improvement of the overlapped motion compensation technique will be made in section F.3. If one of the surrounding blocks is coded in INTRA mode, the corresponding remote motion vector is not set to zero, but replaced by the current motion vector. In annex C, it will be added that only QCIF (Quarter Common Intermediate Format ) bitstreams will be used in Continuous Presence Multipoint mode. LBC-95-271 (B. Haskell, AT&T) contains proposals on H.263 bitstream and MPEG1 (Motion Picture Experts Group 1) half-pel interpolation. It concludes that it is not a good idea to change the H.263 bitstream at this late stage and that the white paper change to the H.263 half-pel interpolation should be rescinded and returned to the MPEG1 method. LBC-95-290 (Y. Machida, Matsushita and Y. Nakaya, Hitachi, Japan) proposes a correction to PTYPE Bit 1 as well as some editorial changes.

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EXTENSION OF MOTION VECTOR RANGE

LBC-95-271 (B. Haskell, AT&T) and LBC-95-278 (Telenor R&D) support the extension of the motion vector range from [-16,15.5] to [-31.5,31.5] if no changes are made to the current H.263 bitstream. LBC-95-278 proposes to change the definition of the vector differences that are transmitted in such a way that a range of [-16,15.5] can be reached around the predictor instead of around zero. An accompanying tape was provided with simulation results. The proposal was adopted. The extension of the motion vector range will be included in Annex D, Unrestricted Motion Vectors. However, the extended motion vector range is not automatically used if the advanced prediction mode is used. Only the technique in Annex D with motion vectors crossing the picture boundary is also included in Annex F. HYPOTHETICAL REFERENCE DECODER

LBC-95-297 (BT) proposes a new hypothetical reference decoder (HRD). It is very similar to the HRD in H.261. The rationale behind it is that the new HRD is more or less proven to work and easier to understand for people who know H.261. It was decided to continue with the HRD as it is now in H.263, but based upon the comments in LBC-95-297, two changes to the HRD were adopted. In the resulting text, only the maximum buffer size of the HRD is specified, which depends on maximum video bitrate and maximum picture resolution for the actual connection. H.263 CONFORMANCE TESTING

A short discussion took place on whether to start an activity on H.263 conformance testing. It was felt that this would be quite useful, especially the creation of bitstreams that are very demanding for H.263 decoders and also the development of a program that tests bitstreams produced by H.263 encoders. It was agreed to have an ad hoc group work on this activity after the meeting; several companies indicated a willingness to take part in this activity. COMPARISON BETWEEN H.263 AND H.261

LBC-95-280 (Telenor R&D) describes a comparison between H.263 and H.261. The H.263 coding was performed in the same way as the coding for MPEG4. The H.261 coding was done as close to H.263 as possible. The conclu- sion from LBC-95-280 is that H.263 performs considerably better than H.261 for all tested sequences. The difference seems to be larger for QCIF than for CIF. The difference is also very large (almost a factor 3 in bitrate) for sequences with slow regular motion. It was noticed that H.263 also performs very well in the one example with relatively high bitrate (600 kbit/s). An accompanying tape was provided to subjectively verify the results. Another tape was shown with a comparison between H.263 and H.261 at 48 and 112 kbit/s. The frame rate was 25 frames per second, the picture format was QCIF. The conclusion was that, also at these bitrates, H.263 clearly outperforms H.261. H.263 AS AN OPTION IN H.320

LBC-95-330 (Q3/15 Rapporteur, N. Kenyon, BT Labs) is a copy of a document from the ITU-T Rapporteur for Q3/15, who is responsible for H.320 and related recommendations. This document, which will be a contribution to the SG 15/1 meeting in November, proposes minor improvements to the H.320 series of Recommendations and includes a proposal to include H.263 as an option in H.320 and related Recommendations. This may hopefully speed up the procedure for approval of the H.263 option in H.320. The document was reviewed and a few changes were proposed. In the plenary LBC meeting, there was a complete consensus on the proposal to include H.263 as an option in H.320. MPEG4 TESTS

LBC-95-279 (Telenor R&D) describes the H.263 simulations submitted as anchors to the MPEG4 tests. The adaptive scheme used for the decision to use the PB-frames option or not is explained. In addition, the buffer control and the up and down conversion filters are described. An accompanying tape was provided with the coding results. SPEECH CODER (G.723) The Chair of this work was R. Cox (AT&T Bell Labs).

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EDITING OF DRAFT RECOMMENDATION G.723

LBC-95-253 is the report of the ad hoc LBC speech coding activities June-October 1995. LBC-95-287 is draft Recommendation G.723. The draft submitted to the ITU in July received further minor editorial corrections to bring it into agreement with the bit-exact, fixed-point C source code and to clarify certain ambiguities. Tables 5 and 6 containing the bit order for the high rate and low rate speech coders are now based on individual octets, rather than 16 bit words. This solves the “byte-order” problem that depended on the byte-order convention of the processor. As a preamble to these tables, section 4 now states explicitly that the octets are to be transmitted in the order listed in the table and that the bit orders within the table begin with Most Significant Bit (MSB) on the left and ends with Least Significant Bit (LSB) on the right. Since these two tables needed to be updated, it was decided to re-order the information so that all bits that are common to both the high rate and low rate coder would appear in the same order in both tables. Furthermore, the bits that are common for comfort noise, for example, generation frames (RATEFLAG, VADFLAG and 24 LPC bits), are listed at the beginning of both tables. Other than the corrections in section 4, there were only two other very minor corrections. Equation (18) had a minor error corrected and Table 8 had two minor corrections made to it. This version of the draft Recommendation will be submitted to the ITU as a delayed contribution for Study Group 15. NEW VERSION OF THE C CODE

A new version of the C source code will be distributed and will contain the revised ordering of the bitstream. All bitstream read/write operations will be performed on an octet basis. It will also contain a minor correction that was discovered to be necessary during the preparation of the test vectors. It was decided to eliminate the Bad Frame Indicator words from the bitstream. This will make the bitstream in exact agreement with the draft Recommendation. In order to operate the decoder with simulated frame erasures, a second file, synchronized with the bitstream, will need to be input to the decoder. This was in agreement with the draft Recommendation, section 3.10, where it states that the error concealment “strategy must be triggered by an external indication that the bitstream for the current frame has been erased.” It was anticipated that this code will be ready for distribution by November 8, 1995. Audio Codes agreed to take responsibility for preparing this new version of the source code. This source code will be distributed as version 4.0 by DSP Group to all organizations who have received the previous version. Others wishing to receive the code should contact S. Huang of DSP Group. She may be reached via e-mail at [email protected]. When G.723 is formally ratified by the ITU-T, this version of the C source code will be provided to the ITU-T and will then be available to non-members. Purchase of the source code from the ITU-T will not provide purchasers with any intellectual property licenses. TEST VECTORS FOR G.723

LBC-95-324 (D. Massaloux and J-P. Petit, France Telecom/CNET) describes a set of test vectors generated for G.723 and how implementers may use them. They were prepared to distribute them to anyone already having ver- sion 3.0 of the C source code. They found that one small correction to the version 3.0 source code was necessary. In addition, in order to have a comprehensive set of test vectors, it is required that for some of the test vectors, the highpass filter at the input of the encoder, or the adaptive pot filter at the output of the decoder, must be disabled. The test vectors will be available on the ftp site: ftp.std.com/vendors/PictureTel/h324. As soon as version 4.0 of the source code is distributed, France Telecom/CNET will prepare a new version of the test vectors that will be in agreement with version 4.0. VOICE ACTIVITY DETECTION AND COMFORT NOISE GENERATION

The proponents presented their collaborative effort on a voice activity detector (VAD) and comfort noise generation (CNG) scheme for G.723. LBC-95-329 (D. Massaloux and J-P. Petit, France Telecom/CNET) explains the al- gorithm used for comfort noise generation. France Telecom/CNET also provided a digital audio tape that compared the performance of the silence compression scheme with the fixed rate 6.3 kbit/s version of G.723. LBC-95-329 will be used as the basis for Draft Annex A/G.723. This annex will also include details on the voice activity detection algorithm. It was intended to submit LBC-95-329 as a delayed contribution for the November 1995 meeting of Study Group 15 and put it forward for determination. A schedule was outlined for finishing work on this annex. Bit-exact, fixed-point C source code for both the VAD and CNG is to be ready for distribution by December 15th. It will be known as version 5.0 of the C code. Version 5.0, running without silence compression, will have exactly the same operation and performance as version 4.0. A run-time switch will enable the use of silence compression. France Telecom/CNET agreed to take responsibility for

December 1995 Vol. 6.8 Copyright © CSR 1995 15 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS preparing version 5.0. Participating organizations will be encouraged to help in the testing of this code by performing objective measurements and/or subjective experiments with it. The goal is to characterize the performance of the silence compression system. Using appropriate source material, the efficiency of the system can be measured by measuring the amount of reduction in the size of the bitstream. A comparison of the performance of version 5.0 with and without silence compression is needed. Hopefully, some of these objective measurement tests can be performed before the next meeting of the LBC group. It was also pointed out that based upon previous experiences with such systems, when operating in silence compression mode, G.723 might not successfully pass network signaling tones. Its performance needs to be investigated. A proposed subjective test was also outlined. A comparison category rating test (CCR) will be used for many of the same conditions that were included in the original selection phase tests of G.723. These include speaker dependency, input level variation, and background noise conditions such as babble and office noise. No test with music as a background noise will be performed, as the CNG cannot be expected to render music. Listening will be done on both loudspeakers and either headphones or hand sets, as was the case in the selection phase tests. The source material should be appropriate for testing the silence compression system, rather than simply using the typical 8 second, two-sentence stimuli often used for category rating tests. Both IRS (Intermediate Reference System) and flat- weighted speech should be used for test samples. It would also be highly desirable if some form of conversational testing could also be performed using the VAD/CNG algorithm. The goal is to complete the subjective tests before the April 1996 meeting of the LBC group. A change in draft Recommendation H.324 was requested to include silence compression as part of the capabilities exchange. The bitstream for silence frames had been defined in Annex A, but it was not part of the main body of draft Recommendation G.723. Only G.723 receivers that are in compliance with Annex A will be capable of accepting silence frames. At the present time, there will not be encoders or decoders having the silence compression features. However, in the future, once Annex A is approved, it may be the case that encoders with the silence compression feature will try to use it with decoders that lack this feature, resulting in degraded speech quality. (The output speech, after a silence interval, may be missing its initial consonant, resulting in degraded intelligibility.) A solution to this problem would be to have information on silence compression exchanged as part of the call setup protocol. Unless both G.723 terminals have the silence compression feature, it should not be used during the call. The editor of H.324 agreed to make this change. Once Annex A is approved by the ITU-T, inclusion of silence compression capability will become mandatory for G.723 terminals. FLOATING POINT SPECIFICATION OF G.723

M. Keith (Intel) had led a group in preparing an interoperable floating point version of G.723. LBC-95-325 (Intel) is that status of the floating point specification for G.723. M. Keith’s original code was tested by France Telecom and then updated. The new version is called version 3.01 and is available from Intel, provided that a simple registration agreement is signed. (The last page of LBC-95-325 contains the form. M. Keith’s e-mail address is [email protected].) Preliminary results for this coder appear promising. These results include both objective signal-to-noise ratio measurements and A-B subjective comparison tests. It was decided to proceed with a floating point specification of G.723 as Draft Annex B/G.723. It was also decided to receive guidance from the entire LBC group as to how much need be included in Annex B. Just as the bit-exact, fixed-point C source code is the real basis for draft Recommendation G.723, the floating point C source code would be the real basis for Annex B. In addition, it was proposed to provide implementation verification procedures for verifying compliance with the floating point specification. Since the mathematical description of the coder is the same as that given in G.723, except for the precision, there seemed to be little to describe in the Annex other than the existence of the C code and the verification tools and test vectors. Since versions 3.0 and 3.01 of the source code were already available to ITU members working in the LBC group, the Speech Coding Group invited active members to obtain the code and run their own comparisons of the two coders on speech files of their own choosing. Of specific interest were: (1) whether the floating point code produces similar outputs when compiled and run on different computers, and (2) reports of any large measured differences between the two coders. SNR (Signal to Noise Ratio) and segmental SNR programs for measuring the difference are available from the Software and Hardware Tools Group in SG 15. A floating point specification for G.723 would need to be evaluated in a formal subjective test using A-B comparisons between the reference fixed-point coder and the possible floating point/fixed point combinations. A proposed subjective test was defined. The Editor for G.723 agreed to prepare a separate document describing the test and circulate it to members of the LBC Group. The test plan will be based on a similar test used to demonstrate interoperability between G.728 floating point and fixed point specifications. Since there will be no difference in quality produced by version 4.0 of the C code, the test could be performed on the basis of versions 3.0 and 3.01.

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France Telecom agreed to perform the test in French and the Speech Coder Group is looking for one or more other participants who are willing to conduct the test in another language. The floating point code will be updated to match updates of the fixed point code described earlier in this document. In addition, the floating point group intends to continue working on the software tools and test vectors needed for verification. One or more proposals are expected to be submitted to the next meeting of the LBC Group. MOBILE APPLICATIONS OF G.723

The Speech Coder Group met with the Mobile Group to discuss channel coding schemes to be combined with G.723 for channels. LBC-95-272 (J-M. Muller, Bosch Telecom, Germany) proposes a scalable channel coding scheme for G.723 that can be adapted for any wireless channel. It was the consensus to go forward with this work and submit a delayed contribution to the November 1995 SG 15 meeting proposing Annex C for G.723 concerning channel coding of G.723 for mobile applications. The draft will be based upon LBC-95-272. An ad-hoc mobile/speech coding group will be formed for activities during the period between this LBC meeting and the next one in January 1996 under the chairmanship of J-M. Muller (Bosch). Members of the group will investigate the proposed scalable channel coding scheme with the goal of refining and improving it. During the next 4 to 6 weeks, Bosch will work on creating portable ANSI C code for the scalable channel coder that will interwork with the G.723 speech coder bitstream. Among the features of the code will be: at run-time, the bit rates of both the speech coder and the channel will be selectable. It was also agreed to provide GSM (Global System for Mobile communications) and TETRA (Trans European Trunked digital RAdio) bit error patterns. Members of the ad-hoc mobile/speech coding group were invited to experiment with this software. In addition to gaining familiarity with the system, they were invited to investigate the bit error sensitivity tables for the 5.3 and 6.3 kbit/s speech coders to determine if changes are needed. The current tables were based solely on objective SNR measurements and may need some adjustment based on human perception. The members are to investigate the effects of changing the CRC (Cyclic Redundancy Code) code from 3 bits to 4 bits. While increasing the number of bits will reduce the number of unde- tected frame erasures, it will also reduce the number of bits available for channel error correction. They were instructed to report any problems that they discover with the code, as well as any solutions they may find for these problems. In addition, they are to suggest methods for testing the efficacy of the proposed channel coding scheme, and they were invited to submit formal contributions for formal testing at the next LBC meeting. OTHER MATTERS

The Speech Coder Group discussed several other contributions. LBC-95-262 (R. Ivy, Electronic Systems Products for Iterated Systems, Inc.) is the Draft Proposed Requirements Document for Real-Time Audio/Visual Conversational Services Applications. It was found that 300 ms delay for the audio codec, including processing, is too large. It was agreed that this large delay would be a major impedance to real-time conversations. This opinion was conveyed to R. Ivy to provide feedback to MPEG4. LBC-95-258 (B. Haskell, AT&T) is the report of the H.26P/L Ad Hoc Committee. The Speech Coder Group noted in this report the large number (32) of audio contributions to MPEG4. On the issue of a new number for G.723, a new number was preferred to avoid confusion with the previous Recommendation G.723. Further, preference was for it to be a previously unused 3 digit G series number and not G.7231 or any other 4 digit code unless no 3 digit codes are available. I. Varga (Deutsche Thomson Brandt) agreed to take over as Editor for G.723 and Chair of the ad-hoc LBC Speech Coding Group effective after the November 1995 SG 15 meeting. R. Cox (AT&T Bell Labs) will continue up until that meeting. MULTIPLEX (H.223) The chair of this work was V. Eyuboglu, Motorola. The Multiplex Group reviewed the revised draft Recommendation H.223 given in LBC-95-286© (V. Eyuboglu, Editor H.223, Motorola ISG). The Editor presented the changes in the new draft relative to the July white paper described in LBC-95-255, the Multiplex October meeting report. All proposed changes were accepted, except one that related to the XOR (Exclusive OR) procedure described in LBC-95-277 (D. Lindbergh, PictureTel), Improved H.223 Error Detection. The relevant sections of H.245 on the Multiplex Entry Syntax and Procedure were compared against corresponding text in the H.223 July white paper. Some discrepancies were discovered, and text was added to H.223 or H.245 to remove these discrepancies. LBC-95-277 and LBC-95-292 (H. Singh, AT&T) were reviewed. LBC-95-277 proposes that each octet in the H.223 MUX-PDU (Protocol Data Unit Multiplexer) body be XORed with the header octet in both transmitter

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and receiver. LBC-95-292 proposes adding verbiage to the SDLs (Specification and Description Languages) in H.245 to improve clarity. After a fairly long debate, it was decided not to adopt these proposals. It was agreed, however, to include the XOR procedure proposed in LBC-95-277 as an option in H.223, but not to use this option in H.324. The Editor will prepare the final version of Recommendation H.223 for submission in November to SG 15 as a delayed contribution and will make it available on the H.324 ftp site. COMMUNICATION CONTROL (H.245) B. Welsh, BT Labs, was the chair of this work. A meeting of the H.245 Ad Hoc Group was held just prior to the LBC meeting in Darmstadt. The report on this group’s work is contained in LBC-95-261 (B. Welsh, Chair, BT Labs). It contains 21 items that summarize the issues brought up by the H.245 Ad Hoc Group and has four annexes written by M. Nilsson (BT Labs) containing alternative text and syntax for some of the procedures. The H.245 Ad Hoc Group reached agreement on most of these items during the meeting, leaving a few more significant issues to be resolved at the main meeting. LBC-95-307 (D. Skran AT&T, editor H.22Z) discusses mapping H.221/H.230 (H.320 frame structure and H.320 control and indication) commands to H.245 commands. It notes that unless mapping is defined, interoperability problems will be likely. During the main meeting, three significant issues were discussed and agreement was reached. 1. Actions to be taken in the event of timer expiry It was decided to put timer expiry procedures for capability exchange and master-slave determination into H.245 with some editing to the SDLs and text of the procedures section based upon the proposal given in LBC-95- 331 (H. Singh, AT&T Bell Labs). 2. Bi-directional logical channel signaling It was decided to adopt the proposal on bi-directional logical channel signaling suggested in LBC-95-296 (M. Nilsson, BT Labs) with a modification to require that a responding terminal send an open logical channel PDU after it has sent its acknowledgment to the initiating terminal. 3. Master-slave determination procedures It was decided to adopt the proposal of additional verbiage given in LBC-95-292 (H. Singh, AT&T Bell Labs) which requires some modification to the procedures to prevent a terminal sending an MSD (Master Slave Determination) PDU with a new status determination number unless it has received a REJECT message from the far-end terminal. An addendum to LBC-95-261 was produced documenting the changes; it was agreed to append this to a liaison to the AVC (Audiovisual Conferencing) group meeting the following week. The H.245 draft was edited according to the agreed upon changes, and it was put onto the LBC and AVC reflectors shortly after the end of the meeting. SYSTEM (H.324) The H.324 Group, chaired by D. Lindbergh (PictureTel), reviewed LBC-95-250, the Editor’s proposed final draft of H.324. It incorporated a few editorial improvements to the text that were accepted, except as noted below. In addition, changes were proposed in the following contributions to this meeting. LBC-95-281 (J. Magill, Q1/14 Rapporteur - SAVD, AT&T) is a proposed liaison statement from Q1/14 SAVD to Q5/8, Q19/8 and Q2/15 (Multimedia Terminal). It requests comments on the application of framed QADM (Quadrature Audio Data Modulation) to V.34 modulation. Four contributions are attached. Three of these are technical contributions that were reviewed at the October meeting of SG 14 WP 1. The remaining contribution is the meeting report on high speed modems from Q1/14. LBC-95-282 (J. Magill, Q1/14 Rapporteur - SAVD, AT&T) is a liaison statement from Q1/14 SAVD to Q5/8 and Q2/15 (Multimedia Terminal) requesting views on the usefulness of a new procedure called V.dispatch. Three attachments are included: • A proposal from Microsoft for the definition of a standardized method of switching services using a common modulation mode. • A liaison statement from Q10/8 on the same subject • A report of an ad hoc meeting on V.dispatch that took place at the Q1/14 SAVD meeting held in August.

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LBC-95-284 is the draft Recommendation V.8bis. LBC-95-335 provides copies of drafts V.dsvd-system, V.dsvd-control and V.gmux. LBC-95-293 (H. Singh, AT&T) proposes changes to section 6.6.1 (Interface to multiplex) of draft Recommendation H.324. LBC-95-322 (D. Lappe, Robert Bosch GmbH) describes some basic constraints for the interworking between fixed and mobile networks. LBC-95-327 (F. Henkel, Deutsche Telecom) discusses call control procedure for videophone hybrid (H.320/324) terminals connected to the ISDN. LBC-95-328 (F. Henkel, Deutsche Telecom) discusses videophone interworking connected to the ISDN and to the PSTN identifying the problems associated with utilizing an interworking function (IWF). It notes the need to define how the called party number can be delivered to the IWF. LBC-95-331 (H.245 Ad Hoc Group) proposes text for addition to draft Recommendation H.324. It addresses actions to be taken when certain exception conditions occur. The following changes to H.324 (LBC-95-250) were agreed upon: Changes affecting H.324 draft for November 1995 SG 15 Decision: • Will add note to 6.5.3 (Mode preferences) saying that compliance with received Request Mode messages is optional (but preferred). Probably: “Transmitters may deny such requests, but should comply if possible.” • Will insert a new 6.5.4 (in front of the existing 6.5.4), covering H.245 timer and counter values. This will say (from item (b) of LBC-95-293) that all H.245 timer values shall be at least N400*RT delay, and that retry counters N201, N206, and N2061 (all to be defined in H.245) should be at least 3. • Section 11.1.2 (System loopback) to be removed and marked “For Further Study” since all proposed mechanisms to make this work depend on as-yet-undefined V.34/V.25ter features. It was felt that this should probably be addressed by V.34 directly and may not be needed in H.324 at all. In any case, it needs more work. • Section 11.1.3 (Media Loopback) will add at end of first paragraph: “Media loopback provided a subjective test of H.324 operation through the far-end codec for human user evaluation. It should be used only on video and audio channels.” • In section 6.3 (Modem), remove references to V.8bis from first paragraph. Add “NOTE: Support of V.8bis is optional, but it is the intention of ITU-T to add a requirement for Rec. V.8bis in the May 1996 revision of Rec. H.324. Implementers are encouraged to include V.8bis support as soon as possible prior to that time.” • In section 6.7 (Audio channels), change “G.723 receivers shall be capable of accepting silence frames.” to “...may optionally be...” for November 1995 version only (restore for May 1996). Add note that ITU-T intends to make silence frame decode mandatory in May 1996. • In section 7.2.2 (V.8bis procedure, Phase B), replace second paragraph with “If the terminal is conditioned to go directly into digital communication mode, phase B shall be bypassed, proceeding directly to phase C. If the terminal is conditioned for initial analog telephony voice mode, the terminal shall proceed to phase C when (bullet) the user manually causes the terminal to initiate a V.8bis transaction, or (bullet) the terminal detects an initiation signal from the distant terminal.” • In section 7.3.2 (V.8bis procedure, Phase C), remove entire section prior to “Upon completion...” and replace with “The terminal shall follow the call start-up procedure described in Rec. V.8bis. If the V.8bis procedure detects that the distant terminal is not capable of V.8bis, but is capable of V.8, the Phase C procedure of V.8 (above) shall be followed. If the V.8bis procedure detects a distant H.324 terminal, the V.34 start-up procedure shall be followed.” • Replace Appendix I (V.8bis codepoints) with an Appendix (normative) describing the actual V.8bis H.324 codepoints and their proper use. (This will be non-normative in the November version, but will be a normative Annex in the May 1996 version.). • Add text to Multiplex section saying that optional H.223 XOR procedure (LBC-95-277) shall NOT be used in H.324 terminals. • Replace Appendix I (V.8bis) with new version, including notes regarding plans for May 1996. • Add Bit/Octet order Appendix (non-normative) from e-mail & V.8bis (LBC-95-284) page 7. Changes affecting H.324 draft for November 1995 SG 15 Determination (May 1996 Decision) in addition to above: • Update V.8bis reference. • In section 6.3 (Modem), add requirement for V.8bis, remove V.8bis note. • Remove section 7.2.1 (V.8 procedure, Phase B).

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• In section 6.7 (Audio channels), restore “All G.723 receivers shall be capable of accepting silence frames.”, remove NOTE about this. • In section 7.2.2 (V.8bis procedure), strike “When the procedures of V.8bis are in use” from first paragraph. • In section 7.3 (Phase C), rename sections (and reorder) to show that V.8bis procedures are required, and V.8 procedure is used only as a fallback. • Add Appendix (non-normative) on use of V.ib and V.25ter with H.324. This was an open list. There was intention to add additional items before May 1996. MOBILE (AV.32M) D. Lappe (Robert Bosch GmbH) was the chair of the Mobile Ad Hoc Group. REQUIREMENTS

LBC-95-256 and LBC-95-347 are the reports of the mobile ad-hoc Committee. LBC-95-256 notes that a short term introduction of a mobile videotelephone is possible. Stimulated by LBC-95-294 and LBC-95-295, from BT, the requirements for a mobile videotelephone were discussed. The following was agreed upon: • H.324 should be adapted to be able to be transmitted via wireless networks. The same requirements as for the PSTN-videotelephone are assumed, for example, delay (one way) < 300 ms. • A transparent channel is assumed. • AV.32M must be scalable in a wide range of network constraints. LBC-95-294, Experiments (1990 to 1993) on the transmission of compressed video (H.261) over radio links (BT), proposes a transmission protocol for use in AV.32M. LBC-95-295 (BT) discusses the current status and direction of work on the mobile multimedia standards, AV.32M, and expresses concern that some of the currently proposed ideas would not be optimal from the interworking point of view. H.245, AV.24M A rate adaptation between PSTN and Mobile was considered necessary. This is possible with H.245. The possibility to open a logical channel for mobile networks had been requested and discussed with the systems group. AV.26M LBC-95-304 (R. Fischer, Robert Bosch GmbH) is draft Recommendation AV.26M, video coding for low bitrate communication. LBC-95-267 (Telecommunications Inst., Univ. of Erlangen-Nuremberg) is a proposal for an H.263 compatible method for robust video transmission in a mobile environment. Feedback information is used to stop spatio- temporal error propagation. LBC-95-291 (NTT DoCoMo) describes a method that utilizes priority based re-ordering technology for error control and tough synchronization. UEP (Unequal Error Protection) in combination with the EREC (Error Resilience Entropy Code) coding scheme is applied. LBC-95-294 (BT) describes hardware experiments performed on a transmission of compressed video over the DECT (Digital European Cordless Telephone) radio link with H.261 at 32 kbit/s. It is a proposal to use a hybrid scheme with ARQ (Automatic Repeat Request) and FEC (Forward Error Corrector) Interleaver. LBC-95-295 (BT) considers the current status of AV.32M, and expresses concerns about interworking requirements, syntax re-ordering, and fixed length multiplex patterns. The wish is expressed to have a rate adaptation possible, signaled with H.245. LBC-95-321 (D. Lappe, Mobile Ad Hoc Group Chair, Robert Bosch GmbH) provides comments on LBC-95- 294 and LBC-95-295. It attempts to answer questions and address concerns. LBC-95-309 (X. Ran, National Semiconductor) describes a core experiment with ARQ. It is proposed to use sub-videos with re-transmission and intra refreshing. The GOB (Group of Blocks) boundaries are treated as picture boundaries. This provides a considerable improvement in picture quality. Hence, the Video Group was asked whether or not it is possible to have this proposal included in the actual H.263. It was decided to use PEI and PSPARE codes in H.263 for that.

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LBC-95-311 (R. Fischer and R. Mann Pelz, Robert Bosch GmbH) presents simulation results for the TCON (Telenor Research’s error concealment decoder) model and the model described in the proposal for the draft, which is characterized by UEP and a soft output (LBC-95-304). Although the gain in picture quality was up to 1.5 dB in SNR, it was decided not to consider this proposal for the mobile standard since the delay of one frame is not acceptable and it changes H.263. LBC-95-326 (R. Mann Pelz, Robert Bosch GmbH) describes a technique to enable a channel sensitive error detection with usage of bitwise reliability information (Soft Output Viterbi Algorithm, SOVA). LBC-95-318 (J. Nowak, Motorola) requests that for a selection of a particular FEC, the expected application, channel condition, and video quality are considered. LBC-95-323 (Ericsson) is a proposal to improve the fixed length code table for the DCINTRA and TCOEFF. The possibility of introducing a codepoint in the H.263 bitstream for mobile had been discussed together with the Video Group. It was instead decided to use the PEI and PSPARE bits. VIDEO EXPERIMENTS

It was intended to provide a complete technical solution for the AV.26M including ARQ, flexible FEC, and a flexible interleaver. It was assumed that adaptation needed to be made to the networks GSM, DECT, and PHS (Personal Handyphone System). Other than this, the AV.26M will be flexible enough to be adapted to other mobile networks. The attempt is not to change H.263 itself. NTT DoCoMo checked whether it is possible to provide a mobile/ mobile PHS sequence (also for the MUX experiments). The following experiments were agreed upon: • ARQ -- Proceed with the experiments according to LBC-95-309. Comparisons between the methods proposed in LBC-95-267 and LBC-95-309. • FEC+INT. • LBC-95-323 proposal with the following schedule: 1) specification of the simulation conditions, 2) presenting the simulation results to the reflector, and 3) decisions and document at the next meeting. • It was agreed to use no special protection on the PSC (Picture Start Code). AV.22M LBC-95-276© is the draft Recommendation AV.22M, Multiplexing Protocol for Low Bitrate Multimedia Mobile Communication. It includes the changes agreed upon at the June meeting. Although the performance of the agreed scheme has been approved by simulations in LBC-95-275 (P. Crespo and J. Garcia-Frias, Telefonica Investigacion y Desarrollo) and LBC-95-268 (J. Villasenor and B. Dowling, UCLA), it was requested by the Multiplex Group to perform experiments in order to compare the AV.22M with an approach where the existing H.223 remains mainly unchanged. LBC-95-298 (T. Nakai, OKI, Japan) comments on the AV.22M proposal and raises problems with the fixed length packets of the MUX PDU. It is also remarked that an ARQ is not included in the current scheme, and that the partition of channels into blocks of minimum length causes delay. It was desired to improve this issue particularly. The following steps toward a mobile multiplexer were discussed and agreed upon: • Simulation with H.223 plus additional error protection (H.263 + G.723 bitstreams are to be sent). AV.22M = H.223 + error protocol. • Strategies to achieve a stable state: a) FEC, ARQ, FEC+ARQ -- The MUX bitstream is transparent. No special error protection of sync and Header. b) The structure of the MUX-PDU is known to the error protocol: – Replacement of 8 bit flag by a barker code – Special protection of the header – Protection of the payload in the AL • Simulation of the AV.22M proposal (LBC-95-276©) with use of fixed length PDU. The possibility of ARQ must be provided. ARQ must be used in the same way in both cases. • Statistical investigation in Synchronization capabilities for the first two experiments above. It will be checked if the Reed Solomon code already available to the group is sufficient for the first experiment. If not, an executable file for a proper equal error correction will be provided to the reflector.

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E-MAIL PROCEDURE TO DEFINE THE EXPERIMENTS

Since it was intended that AV.32M be finalized at the January LBC meeting, the following procedure was agreed upon: • Proponents were requested to define experiments in detail on e-mail, inviting parallel experiments prior to the next meeting. • If there is only one experimenter and there are no objections on the reflector, it was agreed that the result will be considered by the LBC group. It was requested that the experimenters provide results and changes to the experiment on e-mail. H.263L FUTURE VIDEO CODER B. Haskell (AT&T) chaired this group. LBC-95-306 (JCG on AVMMS) is the July meeting report of the Joint Coordination Group (JCG) on AudioVisual and MultiMedia Services (AVMMS). It was presented at the opening plenary and indicated that the ITU AVMMS organization suggested that the ITU should not investigate advanced video coding techniques going beyond H.263. LBC-95-302 (report by R. Ivy) notes that the MPEG-4 committee, when requested to reserve a profile for real time audio/visual conversational services and develop a verification model, (VM) for the applications area, stated that it did not expect to have profiles and that VMs were not expected to ad- dress application areas. The LBC Experts Group disagreed with both these conclusions, and support for this LBC position was provided in LBC-95-303 (R. Ivy, ESP/ISI), Rationale for the Advanced Video Coding Project - H.263L. LBC-95-303 outlines the “Requirements for Real-Time Audio-Visual Conversational Services Applications.” It was reviewed by the LBC Group, modified, and fully approved. It will be submitted to the ISO/IEC MPEG-4 meeting as a liaison document. H.324 TESTING C. Gates (Creative Labs) chaired this work. The following is the report of the work (LBC-95-254) of the H.324 Test Ad Hoc Committee during the interim period between the June LBC meeting and the October LBC meeting. At the June LBC meeting, it was agreed to set up an e-mail reflector where participants in the Ad Hoc group could post non-real-time H.223 bit streams as well as discussions concerning H.324 test. Several contributions were made containing H.223 bit streams conforming to a plan defined in LBC-95-199 (Creative Labs) that defines real time tests over the PSTN. These bit streams were decoded by some of the companies participating, and the results were reported back to the contributor. There were problems with getting the bit stream reflector to work properly, but these problems were resolved. Some ambiguities were found relating to the H.223 CRC. These were reported to the H.223 Ad Hoc Group for clarification. LBC-95-332 (C. Gates, Creative Labs) describes a set of test scenarios that could be used for testing components of the H.324 system in real time. It was discussed as a basis for real time inter-operability testing, and some modifications were suggested. LBC-95-332RevA contains the revised document. Several members pointed out that further work in non-real-time testing needed to be done. The idea of having an ad hoc meeting in January where companies could bring implementations to test was suggested. Although many members felt that this would be a good idea, nothing like this had been done before in the ITU, and it was pointed out that some companies may have problems with this approach. It was agreed to look into this idea further before planning a meeting. A contact sheet was passed around so that interested parties could sign up as contacts for H.324 inter-operability testing. The thought was that private contacts could be made to set up some tests between the interested parties. These tests could either follow LBC-95-332 or other proposals created privately. This contact sheet will be distributed over the e-mail reflector. The issue of H.263 conformance testing was raised. The idea was to have a set of bit streams that test the corners of the standard that various implementers could use to verify their implementation for conformance with the standard. No one at the meeting was interested in this area. Contributions toward defining the inter-operability as well as conformance tests were encouraged. The forum for this discussion will be the e-mail reflector. The reflector e-mail address is “[email protected]”. To sub- scribe to this reflector, send commands to “[email protected]”.

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Mohammad R. Motamedi Systems Technology Group National Semiconductor 2900 Semiconductor Drive Mail Stop D3-969 Santa Clara, CA 95052-8090 Phone : 408) 721-8765 Fax : 408) 721-7431 e-mail: [email protected] DTE/DCE INTERFACE T. Geary (Rockwell Int’l) chaired this work. LBC-95-259 is the draft report of the DTE/DCE ad hoc interim work June through October. The goal of this group was to define what, if any, additions needed to be requested from SG 14 in the proposed V.25ter (or other emerging recommendations) for various configurations of videophone applications. During this meeting, the DTE/DCE group met as a part of the Systems Group. Discussion focused on LBC-95-315 (L. Brown, Q7/14 Rapporteur, Motorola ISG) and LBC-95-316 (L. Brown, Q7/14 Rapporteur, Motorola ISG) and revealed outstanding progress of the work in the DTE/DCE interface area. LBC-95-315 is a liaison from Q7/14 providing Draft Annex B/V.25ter, Synchronous Data Modes, Draft Annex A/V.25ter, V.8 and/or V.8bis procedures and Draft V.ib (in-band signaling). LBC-95-316 is a liaison statement from Q7/14 providing a status report on DTE/DCE interface work from the Hood River meeting August 13, 1995 including a data port for videophones. The group reviewed the annex to draft Recommendation V.ib under the guidance of L. Brown and requested minor clarification in a couple of areas. (Note: The V.ib draft document was determined for resolution approval at the October SG 14 Working Party meeting, but L. Brown will coordinate the minor changes noted.) LBC-95-317 (L. Brown, TR-30) discusses DTE/ DCE signaling and control for GSTN visual telephone terminal applications and the need for additional functionality in the data port in self-contained videophones. LBC-95-269 (T.A. Geary, Rockwell) contains a liaison from TR-30 to T1A1.5 requesting that consideration be given to extending the functionality of the data port to provide the ability for a DTE to perform control and/or monitoring of local operational parameters of the videophone. Discussion resulted in agreement to generate a preliminary requirements list. Further, it was agreed to generate a liaison to SG 14, contained in LBC-95-339 (T. Geary, DTE/DCE Ad Hoc Chair), including this list for SG 14’s planning purposes. LBC-95-340 (D. Schaphorst, LBC Rapporteur) is a liaison to TR-30 and T1A1.5 acknowledging their contributions on this subject and informing them of the progress. It will include a copy of the liaison to SG 14 (LBC-95-339) as an attachment. The interested members were reminded that there is an e-mail reflector for DTE/DCE related items at [email protected]. This reflector can be subscribed to by sending an e-mail request to [email protected]. The need for continuation of this Ad Hoc Group was discussed, and it was felt that there was still sufficient efforts to recommend its continuation until the January 1996 meeting. Its work will include continued coordination with SG 14’s work on DTE/DCE interfaces and on developing example sessions for use by implementers of the new V.ib. NON-CONVERSATIONAL SERVICES LBC-95-257 is the report of the non-conversational services ad-hoc committee from B. Welsh (BT), chair of this work. It includes a functional mapping of H.245 and DSM-CC. LBC-95-273 (BT) discusses whether an extension to H.324 is necessary for information access. It concludes that information access is currently not supported by H.324 but that it may be possible to provide this functionality using another standard at the application level, such as T.120 or MHEG (Multimedia and Hypermedia Experts Group). LBC-95-274 (B. Welsh, BT) provides applications (messaging, audio-on-demand, surveillance, home shopping and banking) and requirements for H.324 information access. It was suggested that DSM-CC (Digital Storage Media - Command and Control) might be a suitable command and control protocol for accessing information using H.324. It was agreed to send a liaison to MPEG/DSM-CC to ask their opinion as to whether this is appropriate for a low bitrate system such as H.324.

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There was some discussion of the work in Q7/8 on information and document architectures and in Q11/8 on network protocols for multimedia exchange. Concerning T.120 and MHEG use with H.324 for information access, LBC- 95-273 (BT) concludes that T.120 could be used by defining new application protocols or enhancing existing ones (e.g., extensions to T.126 for text support are currently under consideration); MHEG is a framework for multimedia presentations. The protocol is object oriented and has a well-defined bitstream using ASN.1. An MHEG Engine acts as a client, requesting MHEG objects from the server. This client-server model is more natural for information access than the peer-to-peer model implicit in the current H.324. It was agreed to send a liaison to SG 8 for forwarding to appropriate questions and to also send to MHEG. It seemed suitable to use the text of the liaison contained in LBC-95-247 from the June meeting. LBC-95-247 is a liaison statement from the LBC Rapporteur’s Experts Group to SG 7, SG 8, SG 14, the Task Force, and the International Multimedia Teleconferencing Consortium requesting comment and consideration of non-conversational services using H.324. LBC-95-274 (BT) was proposed as a start for producing a requirements document. It contains a list of applications drawn from LBC-95-197 (B. Welsh, BT) and a currently empty matrix listing these applications against an initial list of potential requirements. There were no objections against the structure of this document, and it was proposed to continue the work of the Ad Hoc Group in order to develop it further. There were some thoughts concerning the possibility of coordinating the work of this group with other groups interested in using other types of terminals such as ISDN multimedia terminals and V.dsvd for non-conversational purposes. The Chair encouraged LBC Experts to contribute to the work of the Ad Hoc Group by e-mail. The e-mail address of the reflector is: [email protected]. AD HOC COMMITTEES Fourteen Ad Hoc Committees were established to continue until SG 15 meets in San Jose in January 1996. Richard Schaphorst, Delta Information Systems

THE CSR LIBRARY Subscribers may order copies of documents shown in boldface type from Communications Standards Review, where not controlled. We have a large library of standards work in process and can help you locate other information you may need.

24 Vol. 6.8 Copyright © CSR 1995 December 1995 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS

LBC RAPPORTEUR’S MEETING ROSTER, OCTOBER 17 – 20, 1995, DARMSTADT, GERMANY Richard Schaphorst, Delta Information Systems Rapporteur Australia Spain U. of New South Wales Michael Frater Telefonica Pedro Cresso U. of Sydney Marwan Jabri Sweden Canada Ericsson Goran Bang Motorola ISG Les Brown Telia Research AB Ola Andersson Finland Taiwan Nokia Petri Latva-Rasku CCL/ITRI Hsun-Chang Hsieh Nokia Research Center Jacek Newweglowski UK France AT&T John Magill France Telecom/CNET Phil Boucheron BT Labs Peter Salmon France Telecom/CNET Isabelle Haignere BT Labs Bill Welsh France Telecom/CNET Dominique Massaloux BT Labs Mike Whybray France Telecom/CNET Jean-Pierre Petit USA Lab. d’Electonique Philips Franck Lecanu AT&T Fred Burg Lab. d’Electonique Philips Philippe Perrot AT&T Richard Pauls Lab. d’Electonique Philips Estelle Sonnic AT&T Hardish Singh SAGEM P. Sabatier AT&T Bell Labs Mike Buckley Thomson CERDF Michel Kerdranvat AT&T Bell Labs Richard Cox Thomson, Multimedia Thierry Bassi AT&T Bell Labs Barry Haskell Germany Atmel Abbas Tehrani Bosch Telecom Jorg-Martin Muller Chromatic Research Stefan Eckart Deutsche Telecom Friedheim Henkel Compression Labs Sen-ching Cheung Deutsche Telecom Peter List Comtech Labs Wayne Catlett Deutsche Thomson Brandt Imre Varga Comtech Labs Sinan Othman Intermetall Miodrag Temerinac Creative Labs Corey Gates Robert Bosch GmbH Ralf Fischer DCT Tassos Markas Robert Bosch GmbH Dirk Lappe RTI/DCT Cliff Powers Robert Bosch GmbH Peter Mangold Ess Technology Yuhai Mao Robert Bosch GmbH Peter Vogel GTE Labs Faramarz Azadegan Robert Bosch GmbH Joachim Wolf IBM Zon-Yin Shae Siemens Istvan Sebestyen IIT Keith Barraclough Siemens AG Raphael Haermens Intel Corporation Tom Gardos University Erlangen-Nbg. Niko Farber Intel Corporation Chris Hansen University Erlangen-Nbg. Bernd Girod Intel Corporation Mike Keith University Erlangen-Nbg. Eckehard Stinbach Iterated Systems Richard Ivy University Erlangen-Nbg. Thomas Wiegand Iterated Systems John Muller Israel Iterated Systems Michael Zeug Audio Codes Ltd. Leon Bialik KNK Consulting Kristine Kneib Audio Codes Ltd. Felix Flomen Motorola Christopher Clanton DSP Group/Tel-Aviv U. Yair Beery Motorola ISG Vedat Eyuboglu Imagesoft Avishai Silvershatz National Semi. Mohammad Motamedi Japan National Semi. Xiaonong Ran Matsushita Yutaka Machida PictureTel David Lindbergh NTT DoCoMo Toshiro Kawahara Rockwell Int’l Albert Hsueh OKI Electric Toshihisa Nakia Rockwell Telecom. Tom Geary Korea Scientific-Atlantic Arturo Rodriguez Korea Telecom Joon Hyeon Jeon Scientific-Atlantic Subramania Sudharsanan Korea Telecom Hwang-Seok Oh Texas Instruments Yu Huang Samsung Elec. Gui-Young Jung Texas Instruments Jennifer Webb Samsung Elec. Kyu-Hwan Sim U.S. Robotics George Landsburg Netherlands U.S. Robotics Chester Szcaepucha KPN Research Karel Rijkse Univ. of California John Villasenor Norway Vivo Software Chet Graham Telenor Research Gisle Bjontegaard

December 1995 Vol. 6.8 Copyright © CSR 1995 25 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF THE EXPERTS GROUP MEETING ON G.DSVD OCTOBER 23 – 25, 1995, GENEVA, SWITZERLAND The main objective for the meeting was to review the two short-listed coders, namely those from Audio Codes/DSP Group and from the University of Sherbrooke, and make a selection such that a draft Recommendation could be proposed for determination at the November Study Group 15 meeting (see report in this issue of CSR-T). DSVD-95-45 Rev.2, the report of the September 14-15 meeting in Bethesda, was discussed, and further amended. The final version of the report is DSVD-95-45 Rev.4. While some reservations remained about this report, the Chair pointed out that a single summary report would be prepared at the end of the meeting for presentation to the November meeting of SG 15, and that the individual meeting reports would not go forward. REVIEW OF INCOMING LIAISON STATEMENTS

DSVD-95-47 is a liaison from the Q.1/14 SAVD Rapporteur Group generated during the WP 1/14 meeting in October in Munich. The liaison acknowledged the progress made on the speech coder, and in turn referred the G.dsvd Group to the maturing work on the other DSVD component Recommendations. These were made available to the meeting as : • DSVD-95-48: Draft Rec. V.dsvd-s, dsvd system definition • DSVD-95-49©: Draft Rec. V.dsvd-c, dsvd control procedures • DSVD-95-50: Draft Rec. V.gmux, V.42 LAPM-based multiplexer (Note: the drafts contained in DSVD-95-48 and DSVD-95-49© have subsequently been edited further.) DSVD-95-53, a liaison from Study Group 12 - Speech Quality Expert Group (SQEG), notes that due to the short timescales and other work, SQEG has not had as much involvement in G.dsvd as for other SG 15 speech coders, and wishes to be kept informed of the progress of the work. DSVD-95-54 (SG 12) requests information on the total one-way transmission time for a DSVD modem. It includes a copy of G.114 One Way Transmission Time which provides details on the effect of delay on a telephone call. DSVD-95-55 is the response from SG 14 back to SG 15 listing SVD applications. It states that SG 14 does not consider coder delay to be a significant issue. DSVD-95-56 from the Q.4,8/15 Group notes their desire to utilize the V.42 LAPM-based multiplexer for network-based multimedia applications. Desiring to maintain compatibility with the DSVD work, they note their need to add some capabilities (e.g., UIH frame) and a new control channel for terminal to network control communications. REVIEW OF CODER COMPLEXITY

The proponents of the two coders (Audio Codes/DSP Group and the University of Sherbrooke) introduced contributions giving updated information on the complexity of their respective coders. DSVD-95-57 (Audio Codes/DSP Group) gives information based on an implementation on a Motorola DSP56156 as: worst case MIPS - 9.1, RAM - less than 1.6 kwords, ROM - less than 5.2 kwords. With regard to the MIPS figure, a function-by-function breakdown is provided, as are figures for additional memory required if the coder were implemented together with the G.723 coder. DSVD-95-59 (University of Sherbrooke) gives information based on an implementation on a Texas Instruments TMS320c50 DSP as: worst case MIPS - 11.95, RAM - 2038 words, ROM - 9.08 kwords. Again a function-by- function breakdown is provided. The contribution also provides information on the complexity reduction likely to be achieved through the use of the more recent Texas Instruments TMS320C54x DSP technology. MIPS reduction was estimated at 30% and the ROM requirement was also expected to reduce through the use of the richer instruction set. The intent of the work of the ad-hoc group led by J. Johnston (Rockwell International) was to verify these figures. During this session, a 2.8 second speech segment, from the original speech files as used in the COMSAT tests, was processed on DSP assembly language simulators running on PCs. Details of these test files are contained in DSVD-95-64. Complexity figures were assessed from observation of cycle counts and map files. The DSP simulator output was also compared with that from the “C” code executable used during the subjective testing in

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July. In both cases there was a match, although the University of Sherbrooke required extra time to eliminate a bug in the DSP code before this could be proven. The conclusion of the ad-hoc group, as presented in DSVD-95-60 (plus verbal update confirming resolution of the USH problem), was that the figures presented in DSVD-95-57 and DSVD-95-59 were fair and accurate for those DSPs. The following additional contributions were presented on the subject of complexity. DSVD-95-62 (Rockwell International) points out that factors such as programming expertise and DSP performance need to be taken into account in comparing algorithm implementations from different sources on different devices. Using analysis from Berkeley Design Technology (BDT) Inc. on normalized benchmark cycle counts, Rockwell estimates that both coders require less than 10 MIPS on either a Motorola 56156 or a TI TMS320c54x DSPs, and require more than 10 MIPS on a TI TMS320c5x DSP. DSVD-95-68 (Texas Instruments) discusses the complexity improvement available through the use of the optimized instruction set and enhanced architecture of the TMS320c54x rather than the TMS320c5x. Using other speech coders as benchmarks, a MIPS improvement factor of 1.4 to 1.5 is predicted. DSVD-95-70 (France Telecom/CNET) discusses some of the issues concerned with the selection of a DSVD speech coder, primarily complexity assessment. It points out the difficulty of making complexity comparisons from implementations on different DSPs; it discusses the use of weighted MOPS; and it proposes approximate weighting factors for differing DSPs which are broadly in line with the other contributions. The information from these various contributions seemed consistent in suggesting that the coder from the University of Sherbrooke could meet the 10 MIPS limit if implemented on an appropriate DSP. PRESENTATION OF DOCUMENTS RELEVANT TO CODER SELECTION The meeting considered some additional documents before discussing the selection of a coder. The latest descriptions of the two coders are contained in DSVD-95-58 for Audio Codes/ DSP Group, and DSVD-95-65 for the University of Sherbrooke. DSVD-95-66 (Audio Codes) provides additional information on the bit allocation for their coder indicating that, as not all of the possible combinations were used, it should be possible to minimize the occurrence of bit sequences which simulate HDLC flags, thereby reducing the need for bit stuffing. The resulting discussion concluded that careful calculation would be needed to assess the potential benefit. DSVD-95-63 (Rockwell International) presents an analysis of the data required for each of the proposed G.dsvd coders, and for varying overhead in the V.gmux multiplexer. It shows that for coders with a 10 ms frame size, the bit rate is particularly important if operation over 14.4 kbit/s modems is required. During the discussion, it was noted that the addition of the suspend/resume feature as an option in V.gmux had been agreed by the October WP 1/14 meeting in Munich, and this would reduce the multiplexer overhead. On this subject, Delayed document D.154 from the WP 1/14 meeting was made available as DSVD-95-67 for information. It gives a comparison of overhead between the basic and suspend/resume modes of operation in V.gmux. DSVD-95-52 (PictureTel) addresses interoperability with other multimedia standards, i.e., between DSVD terminals, and H.320 and H.324 terminals for videoconferencing on the ISDN and GSTN, respectively. It notes that while this is an important issue, it has not yet been achieved. Recognizing that the multiplex structure (H.221) of H.320 terminals requires speech codecs operating at multiples of 8 kbit/s, the contribution proposes that the adoption of the University of Sherbrooke coder for G.dsvd, being interoperable with G.729, would facilitate a G.729- based interworking solution across all the terminals. CODER SELECTION DISCUSSION

The discussions on coder selection took most of the time of the meeting. The characteristics of the two coders were compared with the requirements detailed in the Terms of Reference for the work. In general, this discussion con- cluded that both coders met the requirements with the exception of the following areas of concern and disagreement: • Performance in the presence of babble noise The results from NTT (DSVD-95-39 from the September meeting) indicated that both coders failed the babble noise test. Although a further analysis by COMSAT (DSVD-95-43) showed that an alternative processing of the results concluded that the DSP Group coder passed, there was some concern that the test procedures and analysis were not in accordance with SG 12 SQEG standard practice. In any event, the results showed that the performance of two coders was very similar on this test, the COMSAT report indicating that they were statistically equivalent.

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• Talker dependency

The test report form COMSAT (DSVD-95-42 from the September meeting) indicated that all the coders showed some degree of talker dependency, but concluded that further testing was required as the particular test did not involve a sufficiently large number of talkers. While the results were not conclusive, the COMSAT report did indicate that the University of Sherbrooke coder was the least sensitive, i.e., the only coder to pass a two way analysis of variance assessment for all the talkers used. • Coder complexity The Audio Codes/DSP Group coder clearly met all of these requirements. The University of Sherbrooke coder appeared to fail this requirement, however considerable evidence was presented to show that the use of an alternative DSP to that used by the University of Sherbrooke in their simulation, would result in compliance with the MIPS requirement. The expectation of the University of Sherbrooke was that an improvement would also be made on the ROM requirement. The meeting also considered topics such as the possible benefit of interworking with G.729, and the possibility of sharing DSP code with implementations of dual coders. Some felt, however, that as these issues were not in the Terms of Reference, they should not be considered. It was not possible to reach an agreement on either coder. During these discussions, some delegates expressed concern that the Experts Group was now trying to conclude work on a standard which closely matched the characteristics of other coders currently in progress in the ITU, namely G.729. This resulted from the decision of the Experts Group at the March meeting to deviate from the original SG 15 mandate to develop a coder at 13 kbit/s. In March, the Group had decided to aim for the lowest possible bit rate, which, while being in accord with the wishes of SG 14, had not been approved by SG 15. Also, there were factors emerging in discussion which had not been defined in the original Terms of Reference, e.g., interworking or code sharing with other coders. In the absence of an agreement on a coder selection, the meeting agreed to refer the issues to the forthcoming SG 15 meeting such that the revision to the Terms of Reference, and the importance of the newly discussed factors, could be discussed by the wider committee. REVIEW OF DRAFT RECOMMENDATION

The proponents of the two coders introduced contributions giving detailed information on their respective coders in the form of draft Recommendations. These were DSVD-95-58 for Audio Codes/DSP Group, and DSVD-95-65 for the University of Sherbrooke. As most of the time of the meeting had been taken up with the selection discussion, these documents were not reviewed in detail. VOICE ACTIVITY DETECTOR

There were two contributions on Voice Activity Detector. DSVD-95-51 (France Telecom/ CNET) describes a comfort noise generator for the dual rate G.723 speech coder. This paper had been presented the previous week at the LBC meeting in Darmstadt (LBC-95-329), and the proposal was accepted for incorporation into draft Annex A of G.723. France Telecom had indicated that a variant could be designed for G.dsvd. The technique involves the transmission of a Silence Insertion Descriptor (SID) frame instead of a speech frame during periods of no voice activity. The SID is shorter than an active speech frame, and contains information on the characteristics of the background noise. These SID frames are not sent continuously during silence, but only when the noise characteristic changes. DSVD-95-61 (Rockwell) reports that they had tested their VAD design with the G.729 speech coder and verified that the performance was as good as for their own coder, as reported in DSVD-95-33 from the September meeting. The meeting did not have time to discuss these proposals in detail, and this topic was left for discussion at the SG 15 meeting in November (see SG 15 meeting report, this issue of CSR-T). Rockwell indicated that they may have additional test results available by that time. REPORT FOR SG 15

DSVD-95-71 is the outline for the report to the SG 15 meeting, and contains a summary of the selection discussions, noting that no decision had been reached, and that SG 15 approval to the change to the bit rate re- quirement was required. The wording of these parts of the report were amended by the meeting, and additional

28 Vol. 6.8 Copyright © CSR 1995 December 1995 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS background information was added after the meeting. Author’s note: The final version of the report is TD.18 (Gen) from the November SG 15 meeting. John Magill, Probe Communications, UK

G.DSVD EXPERTS MEETING ROSTER, OCTOBER 23 – 25, 1995, GENEVA, SWITZERLAND John Magill, Probe Communications, UK Chair of Experts Group AT&T (USA) Dror Nahumi AT&T (USA) Mike Buckley Audio Codes Ltd. (Israel) Leon Bialik Audio Codes Ltd. (Israel) Felix Flomen Deutsche Telekom (Germany) Gerhard Schroeder DSP Group Inc. (Israel) Yair Be’ery DSP Group Inc. (Israel) Yuval Cohen IBM (USA) Ali Sadri Intel Corporation (USA) Mike Keith Motorola ISG (USA) Art Barabell NTT (Japan) Shinji Hayashi PCSI (UK) Harprit Chhatwal Rockwell Int’l (USA) Huan-yu Su Rockwell Int’l (USA) Jim Johnston Siemens (Germany) Marcus Terschluse Siemens (Germany) Istvan Sebestyen Sipro Lab Telecom (Canada) Laurent Amar U. of Sherbrooke (Canada) Claude Laflamme

December 1995 Vol. 6.8 Copyright © CSR 1995 29 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF TR-30, DATA TRANSMISSION SYSTEMS AND EQUIPMENT NOVEMBER 13 – 17, 1995, ORLANDO, FL TR-30.1 MODEMS Technical editor’s note: The following files have been placed by L. Brown (V.8bis Rapporteur) on his ftp site: [email protected] directory /vendors/Motorola_ISG/. These files are the same as those sent to the ITU-T as final documents, as of 12/14/95. • V.8bis rev 8 • Annex A/V.25ter (V.8/V.8bis DCE control) • V.ib rev 6 (in-band control) • V.dsvd-s (system doc.) • V.dsvd-c (control doc.) • V.gmux (dsvd multiplexer) TR-30.1/95-11-142 (D. Brandt, TR-30 Chair, AT&T) is a summary of the WP 1/14 October meeting (see CSR- T Vol. 6 #7 for a full report of this meeting). TR-30.1/95-11-151 (D. Brandt, AT&T) contains the highlights of the recent meeting of the TIA Technical Committee. A new Satellite Division will reactivate TR-34. The TIA Engineering Manual will be delayed until mid 1996 as it must be reballoted due to changes. D. Brandt also noted a recent decision in ISO/IEC JTC1 to list all known patents in their standards. V.DSVD-S, DSVD SYSTEMS DOCUMENT

TR-30.1/95-11-138 is the latest version of draft Recommendation V.dsvd-s as presented at the October WP 1/14 meeting, as TD-50rev (J. Magill, V.dsvd-s Editor, AT&T). C. Hansen (Intel) gave a comprehensive review of the document, noting the requirement for V.8bis. During the discussion that followed, the relationship with H.245 was discussed. H.324 utilizes H.245 as the control channel. V.dsvd-s utilizes the control and indications PDUs of H.245 which provides a common encoding and syntax. It was noted, however, that H.245 is a moving target. V.DSVD-C, DSVD CONTROL DOCUMENT

TR-30.1/95-11-137© (C. Hansen, Intel) is the latest version of draft Recommendation V.dsvd-c, dated November 10, 1995. C. Hansen pointed out that as dsvd-c is directly linked with H.245, it cannot be approved until H.245 is stable (see SG 15 WP1 report in this issue of CSR-T for the latest changes to H.245). It describes how the selected subset of H.245 messages are used to control a point-to-point DSVD connection. The question was raised as to how H.245 would be updated as time went on, and it was reported that no procedures had been established. This is a weakness in a system which relies on V.gmux to map the logical channels indepen- dent of the DTEs (Data Terminal Equipment). The example used to highlight the problem was: How would the DTE know which channel contained the left channel information versus the right when a stereo connection was requested? TR-30.1/95-11-143 (C. Hansen, Intel) provides two ladder diagrams of an example connection based on the present text of dsvd-c. The presentation was long, with considerable questions of clarity being answered during its course. Diagram 1 shows a DSVD communications stack.

SCF DATA AUDIO

DSVD-C/H.245

V.gmux

V.34

SCF = supervisory and control function Diagram 1. DSVD communications stack

30 Vol. 6.8 Copyright © CSR 1995 December 1995 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS

V.GMUX, DSVD MULIPLEXER

TR-30.1/95-11-144 (J.H. Derby, IBM) proposes the polynomial to be used for the optional 8-bit CRC (Cyclic Redundancy Code) in draft Recommendation V.gmux. It is the same 8-bit polynomial that is presently specified in draft Recommendation H.223; therefore, it was not formally introduced. It was decided to forward the contribution to the late November Rapporteurs meeting as a TR-30 contribution. V.8BIS

TR-30.1/95-11-140 (LBC Rapporteur) is a liaison from Q2/15 to the SG 14 V.8bis Rapporteur regarding V.8bis H.324 coding. This liaison proposes the expansion of V.8bis capabilities to allow for sub-fields building a tree structure. Two octets for H.324 are proposed with expansion octets supported. TR-30.1/95-11-152 (R. Schaphorst, Q2/15 Rapporteur, Delta Information Systems) supports TR-30.1/95- 11-140 reproducing an earlier liaison from SG 15 (June 1995) describing a proposed a tree-structure in V.8bis. TR-30.1/95-11-139 (L. Brown, Motorola) proposes a way to implement an extra level in the tree structure in V.8bis in a more unified way. It includes changes to the V.8bis rev 7 tables that would be needed to comply with this unified coding method. Changes to the V.8bis text (TR-30.1/95-11-139add) were also developed at this meeting. There was considerable discussion about the need to change to a tree structure, as requested by SG 15; this led to a discussion of how much data should be exchanged in the V.8bis mode. It appeared that all of the presently defined requirements could be accommodated with the existing flat structure, but SG 15 appeared to be intent on building something more expandable. In the end, the problem seemed to be more with the “generalizing” approach, as proposed in TR-30.1/95-11-139 and TR-30.1/95-11-139add, than in just minimally complying with SG 15. It was finally decided that it would be more appropriate to have the V.8bis Rapporteur send a liaison to SG 15 indicating our reluctance to change the text of V.8bis at this late stage. TR-30.1/95-11-145 (K. Ko, AT&T) proposes changes to the text describing the number of HDLC (High Level Data Link Control) flags required. It would allow the use of standard HDLC controller chips. It was decided that this proposal could be supported as a TR-30 contribution if it were modified to eliminate the upper bound on the number of flags (i.e., by removing the “but not more than …” statements). This was documented in TR-30.1/95- 11-156. TR-30.1/95-11-146 (A. Sadri, IBM) proposes a method for selectively requesting an ACK (acknowledgment) to an MS message. It simplifies the detection of ACK, NAK, ANS or ANSam as it is possible that either ANS or ANSam could falsely trigger the FSK receiver. After considerable discussion, it was decided that there was not sufficient support to make this a TR-30 proposal. TR-30.1/95-11-147 (A. Sadri, IBM) proposes that the duration of ANS (Answer Tone) and ANSam (Answer Tone, amplitude modulated) be made the same (5 secs). This was proposed on the basis that it would allow for easier implementation of detectors in software based systems. After some discussion, it was decided that there was not sufficient support for a unified duration of ANS and ANSam to make it a TR-30 contribution. However, a second point suggesting the removal of the requirement for the 75 ms silent period between the ACK and ANS/ANSam was supported, and a new contribution making this one point was drafted (TR-30.1/95-11-154). In the closing discussions, it was also decided to have L. Brown draft a contribution to the Late November Rapporteurs meeting stating that TR-30 does not support the consideration of other modulation modes for V.8bis at this time. OTHER HIGHLIGHTS

TR-30.1/95-11-148 (R. Schaphorst, Q2/15 Low Bitrate Coding Rapporteur) is a liaison from Q2/15 encouraging the work on V.dispatch. It states that, in the interim, they will retain the V.dsvd PDUs (Protocol Data Units) in draft Recommendation H.245. TR-30.1/95-11-153 (F. Burg, Draft Rec. V.gmux Editor) is the final version of draft Recommendation V.gmux, Generic Multiplexer using V.42 LAPM-based Procedures, dated October 1995. TR-30.1/95-11-149 (R. Schaphorst, Q2/15 GSTN Videophone Rapporteur) is a liaison from Q2/15 calling SG 14’s attention to the fact that Recommendation V.54 does not presently accommodate an asymmetric LOOP 2.

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L. Staples (Data Race) once again raised the issue of the need to associate a particular logical channel with a specific physical entity at the far-end. It was confirmed that, as presently defined, H.245 does not accommodate this re- quirement. Considerable discussion led to a decision to generate a proposed liaison, contained in TR-30.1/95-11- 155, which would request J. Magill (Q1/14 DSVD Rapporteur) to address this issue at the SG 15 meeting which was presently in session in Geneva. Dick Brandt, dB Consulting

TR-30.2, DATA TRANSMISSION

ITU-T S TUDY GROUP 14

D. Brandt, TR-30 Chair, provided an overview of the work which took place at the ITU-T Study Group 14 Working Party 1 meeting in Munich Germany during October (TR-30.2/95-011-033). The specific areas which relate to the work of TR- 30.2 were reviewed. Three documents from the Munich meeting were distributed: • TR-30.2/95-11-030: Report on the Q.6/14 Meeting Held on 10 October 1995 (TD-56) • TR-30.2/95-11-031: Summary of Agreed Revisions to Existing and Approval of New, DTE-DCE Interface Related V. series Recommendations (TD-39rev2) • TR-30.2/95-11-032: Proposed Draft Recommendation on Flow Control (D.153) The changes which had been proposed to Recommendation V.24 for the elimination of Circuits 102a and 102b were not accepted; however, the note in that section of V.24 has been modified to indicated that in certain applications they may not be needed. The draft Recommendation on Flow Control is a compilation of the various standard methods which may be used to implement Flow Control between a DTE and DCE. This document is much more like a Technical Bulletin than a Recommendation. PN-3138, DTE/DCE INTERFACE FOR DIGITAL CELLULAR

Work on PN-3138, DTE/DCE Interface for Digital Cellular Equipment, has basically been completed. Draft 4 of the standard (TR-30.2/94-04-013R3) was reviewed by TR-30.2. This draft had also been reviewed at the TR-45.3.2 meeting earlier in the week. The results of that review (TR-30.2/95-11-034) were presented to TR-30.2 by A. Sacuta, TR-45.3.2 Chair. The majority of the comments from TR-45.3.2 were of an editorial nature. One comment, which at first appeared editorial, to increase the maximum data rate for the interface to 128 kbit/s, soon developed into a new work project. The draft for PN-3138 had been referencing EIA/TIA-562 as the electrical characteristics. EIA/TIA-562 includes a maximum data rate of 64 kbit/s, therefore eliminating it from consideration for the new requirement of 128 kbit/s. The resulting discussion indicated a need for a new electrical characteristic standard which would provide interoperability with EIA/TIA-562 as well as EIA/TIA-232. It would, in fact, be a modern day 232-type of electrical characteristic. J. Goldie (National Semiconductor), TR- 30.2.1 ad hoc chairman, indicated that the ad hoc committee has been considering just such an interface for some time and would provide a first draft for such a standard at the February 1996 meeting. Progressing of PN-3138 to ANSI industry ballot will be held up until work is also completed on the new electrical characteristic. G. Lawrence (AMP Inc.) provided the final drawings (TR-30.2/95-11-035) for the connector specified in the standard. These drawings, as well as the comments from TR-45.3.2, will be included in the next draft of PN-3138. Hopefully, work will progress on the new electrical characteristic standard to permit both to be approved for ballot at the February meeting. VERY HIGH SPEED INTERFACE, ELECTRICAL CHARACTERISTICS

TIA/EIA-644, “Electrical Characteristics of Low Voltage Differential Signaling (LVDS) Interface Circuits,” has been forwarded to TIA for publication. It should become available from Global Engineering Documents in several months. ASYNCHRONOUS AND SYNCHRONOUS SIGNAL QUALITY

TR-30.2 has been awaiting contributions on an open project which was to combine the DTE/DCE signal quality standards TIA/EIA-334 and TIA/EIA-404 for almost two years. In addition, the editor for this work has had to withdraw from the task due to a change in his job assignment. At this meeting, TR-30.2 agreed to terminate work on this project. It was felt that whatever advantages which could have been seen in this work are probably long lost and that the existing two standards would serve the community sufficiently.

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DTE/DCE INTERFACE FOR DATA RATES UP TO 116 KBIT/S

Work on this new interface remains on hold awaiting a contribution from J. Moran, Motorola ISG, which has been promised for the February 1996 meeting. This work is to be a final recommendation regarding the connection of signal common and frame ground. It was determined that, since this standard has been nearly complete for many months, with only this final recommendation to be included, the standard would be approved for ballot in February with or without the grounding recommendation. REVISION OF EIA-485

The TR-30.2 ad hoc committee reported that they are continuing work on the revision of EIA-485, “Standard for Electrical Characteristics of Generators and Receivers for Use in Balanced Digital Multipoint Systems.” As part of this effort, a new Telecommunications Systems Bulletin (TSB) will be written which will incorporate the existing application information from EIA-485 as well as new/additional application guidance. It is expected that this work will be completed by late 1996. WITHDRAWAL OF RS-366

F. Lucas, TR-30.2 chair, reported that the TIA ballot to withdraw RS-366 had passed. This compliments the work in ITU-T Study Group 14 which is revising Recommendation V.25 to remove the parallel dialing capability. UNIVERSAL SERIAL BUS

A short discussion regarding the possibility of standardization of all or a portion of the Universal Serial Bus took place. This work is well along within a consortium of companies interested in the work. TR-30.2 would only be involved with a small portion of the interface. It was concluded that it would not be of interest to TR-30.2 to undertake this work at this time, especially considering its near-completion state within the consortium. Fred A. Lucas

TR-30.3 DATA COMMUNICATION EQUIPMENT EVALUATION AND NETWORK INTERFACES J. Douglass (Sierra Semiconductor) suggested that a project be opened to create a standard for testing Low Bit Rate Multimedia Devices. TR-30.3 concurred. R. Breden (TIA) said that in the future, TIA will be using electronic correspondence for distribution of things such as meeting notices. TIA will also be setting up a BBS, a World Wide Web page and internet access for downloading standards. LIAISON REPORTS

FCC Liaison The FCC Billboard for October, 1995 (TR-30.1/95-11-081) was distributed for information. R. Breden (TIA) reported that TIA will be sponsoring an FCC Part 68 seminar and meeting on March 28 and 29, 1996. SG 14 Liaison TR-30.1/95-11-082 (D. Brandt, AT&T), is a summary of October Working Party 1/14 meeting in Germany. D. Brandt reported that the US Proposal for modem testing V.mt (TIA TSB-38 Test Procedures for Evaluating 2 wire 4 Kilohertz Voiceband Duplex Modems) was accepted for Resolution 1 treatment. When it becomes a Recommendation it may be called something other than V.56ter. PN-3459 -- M AKING TSB-37-A (T ELEPHONE NETWORK TRANSMISSION MODEL FOR EVALUATING MODEM PERFORMANCE) INTO AN ANSI S TANDARD.

TR-30.1/95-11-083, Listener Echo Performance, was presented by R. Perez (Bellcore) and B. McNamara (Bell South Communications). They presented data regarding the distribution of values of Signal to Listener Echo Ratio (SLER) on intra-office calls and the effect of SLER on V.34 modem performance. This study found that interoffice calls have a mean value of 27 dB for SLER, while TSB-37-A has a worse case SLER of 36 dB. They also mentioned that loop loss of 3 dB is more typical than the 6 dB loss reflected in line 17A of TSB-37-A. They concluded that listener echo affects modem performance and that TSB-37-A should reflect real world values of SLER. After reviewing the information, TR-30.3 decided that a new line with a higher values of SLER may need to be added

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to TSB-37-A. However, J. Moran (Motorola) and L. Smith (AT&T) should review the findings and make a recommendation. During the ad hoc meeting, J. Moran (Motorola) faxed a response (TR-30.1/95-11-087AH) to Bellcore’s report, Listener Echo Considerations. In the response, J. Moran points out that TR-30.3 was aware that echoes in fact could be as poor as 10 dB, but the round trip delay was typically less than 5 ms. This simply means that if the listener echo is close enough, the modem’s receiver equalizer will take the listener echo. Basically it was felt that when the round trip delay became significant or greater than 5 ms, the Switch would have to deal with the problem anyway, as customers would start complaining about echo problems. It was pointed out that the minimum telephone line simulator delays are in the neighborhood of 12 ms, rather than the 5 ms network delay. Since the test results presented in the Bellcore report were run on a telephone line simulator, they may not be representative listener echo characteristics of a real telephone line. In fact, the problems that Bellcore is reporting may not be caused by listener echo, since most modem equalizers can span listener echoes that are less than 5 ms. However, the problems that Bellcore is experiencing may be caused by the 3 dB loops or talker echo problems resulting from echo canceller distortion. B. McNamara (Bell South Communications) said that they would continue to investigate the problem and report their findings to TR-30.3. PN-3509 -- M AKING TSB-38 (TEST PROCEDURES FOR EVALUATING 2 WIRE 4 KILOHERTZ VOICEBAND DUPLEX MODEMS) INTO AN ANSI S TANDARD.

The following documents were distributed and reviewed: • TR-30.1/95-11-085, Letter ballot for PN-3509. The ballot will be officially distributed by TIA. The comment period will expire on December 15, 1995. • TR-30.1/95-11-084, Connect Reliability Graphs for V.34 modems, shows an alternative way of presenting Connect Reliability test results. TR-30.3 felt the graphs were informative and should be included in the next revision of TSB-38 along with a modified test procedure. However, these graphs should be plotted for both the initial and final connect rates. PN-3251 -- C ELLULAR NETWORK TRANSMISSION MODEL FOR EVALUATING MODEM PERFORMANCE

The following documents were distributed and reviewed: • TR-30.1/95-11-079, Draft 4 of PN-3251 ( Transmission Model for Evaluating Modem Performance). • TR-30.1/95-11-086, Cellular Network Transmission Testing for Evaluating modem performance (W. Henderson, Henderson Communications). After TR-30.3 reviewed and edited PN-3251 draft 4 section by section, the following homework assignments were taken: • M. Pellegrini (TAS) agreed to incorporate TR-30.3’s recommendations in draft 5, which will be distributed at the February meeting. • B. Scott (AT&T) agreed to bring a contribution on MTSO (Mobile Telephone Switching Office, i.e., cellular switching site) modems. • D. Rife (Hayes) will write a definition for ADPCM. • W. Henderson (Henderson Communications) agreed to provide definitions for the definition section. • M. Pellegrini (TAS) and B. Smith (Bell Mobility) agreed to look at Table 1. • M. Pellegrini (TAS) and D. Ginex (AT&T Paradyne) agreed to run throughput tests using 17C, 18C, 19C, etc. with all the loops and some RF Channels. • B. Smith (Bell Mobility) agreed to run tests to characterize a cell site. PN-3507 -- T EST PROCEDURE FOR EVALUATION OF CELLULAR MODEMS PERFORMANCE W. Park (US Robotics) volunteered to be editor for PN-3507. TR-30.1/95-11-088AH, An outline for Cellular Modem Testing Procedures (PN-3507), was generated during the ad hoc meeting. B. Anders (US Robotics) and D. Ginex (AT&T Paradyne) agreed to add text to a number of sections.

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TEST PROCEDURE FOR EVALUATION OF LOW BIT RATE MULTIMEDIA DEVICES

TR-30.1/95-11-089AH, An outline for Test Procedure for Testing Low Bit Rate Multimedia Devices, was generated during the ad hoc meeting. After some discussion, the ad hoc committee decided the following: • The scope of the project should be limited to voice and data testing. • Areas that should be tested include: speech delay, speech quality, multitone signal for testing audio channel quality, effect of speech on data performance, data through-put with and without speech, turning speech on and off, data turning on and off (while in speech mode), effect of retrains on voice, and effect of line impairments on speech and data quality. • Investigate existing DSVD test equipment. • Investigate Mean Opinion Score (MOS). • Contact SG 15 about existing test procedures. • Invite ZD labs to the next meeting. • Invite Analogic to the next meeting. They make a DSVD test box. Jack Douglass, Sierra Semiconductor

TR-30.4 DTE-DCE PROTOCOLS B. O’Mahony (Intel) served as chair in the absence of TR-30.4 chair J. Bain (Motorola). LIAISON

J. Decuir distributed TR-30.4/95-11-113©, a phase 2 draft of ETSI GSM 7.07, AT command set for GSM Mobile Equipment (ME). It was presented for information, with comments invited. Comments should be directed to the editor: [email protected]. J. Decuir noted that Nokia had submitted a paper to the WP 1/14 Munich meeting on dial string modifiers (D.142) which had drawn objection over the choice of characters. Subsequent correspondence with B. Pechey (Hayes, UK) had resulted in an agreement avoiding collisions. PN-2989, EXTENSIONS TO ASYNCHRONOUS SERIAL AUTOMATIC DIALING AND CONTROL

TR-30.4 had sent out PN-2989 for a second time, including three sets of functions: • V.8 DCE Control (Annex A/V.25ter) • Test Commands (Annex X) • Other commands (Annex Y) The ballot comment period closed November 11, 1995. Ballots sent to the chair were not available. Three ballots were brought in by members: • TR-30.4/95-11-109 (J. Decuir, Microsoft): Microsoft voted NO on the V.8 control part, since the material has been extended by ITU Q5/8 and Q7/14 (see TR-30.4/95-11-110 and TR-30.4/95-11-111, in the V.25ter Annex A discussion, below). • TR-30.4/95-11-105 (B. O’Mahony): Intel voted NO on the V.8 control part, for the same reasons. This ballot also objected to two commands in Annex Y: +ACID (Caller ID) and +ADDR (Distinctive Ringing), on the grounds that they are redundant with the +VCID and +VDR commands from TIA IS-101 and PN-3131. • TR-30.4/95-11-114 (D. Rife, Hayes): Hayes voted yes, but noted that new cadences are being defined in the UK and elsewhere. The ballot proposes a new table to add to this section. In discussion, it was noted that ANSI has just published T1.104.02 on Distinctive Ringing. PN-3319, SAVD DCE-DTE INTERFACES

The editor, B. O’Mahony (Intel), presented TD-59r1 (TR-30.4/95-11-108), from the Munich WP 1/14 meeting. It was reported that this was determined for Resolution 1 decision in March, and that WP 1/14 had agreed to make Synchronous Data modems an Annex A of V.ib instead Annex B of V.25ter. During this meeting, some small technical changes were made. The escape character was changed from to . The subparameter was added to support V.34 half-duplex fax. Several codes were added for

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transparency of DC1 and DC3 characters. The numerous data rate codes were collapsed into a four octet: sequence. No action was taken. PN-3131, VOICE DCE CONTROL

The new editor, L. Staples (Datarace) presented his first draft, TR-30.4/95-11-104, PN-3131 R4. The editor incorporated two significant new features and SVD control: • Duplex speakerphone • Add G.dsvd voice compression • SVD control: event detection and reporting The speakerphone material is in section 10.5. The new SVD material is concentrated in sections 4.8, 5.1.3, 6.5, 7.3 and 8.3. It was suggested and agreed to add G.711, G.723 and G.729 to the audio codec list. It was noted and agreed that both of these features are being included in market products, and that standards are needed here. It was noted that speakerphone functions have been requested since mid-1994. In discussion, it was agreed to delete the DSVD control material, since it is directly within the scope PN-3319, Voice/Data Multiplexing the DCEs – DTE-DCE Interface Operations. The editor examined the history of the project and prepared a list of recommended changes, presented in TR- 30.4/95-11-106. They include: • Delete voice translation state - this belongs in the DTE, and nobody uses it now • Stop using event masks • Stop defining service levels J. Decuir noted that GSM 7.07, which references IS-101 in Annex C, does not reference the voice translation feature. It was agreed to drop voice translation mode. V.25TER ANNEX A

The editor, J. Decuir, attended several standards meetings since the previous TR-30.4 meeting, and reported on them in TR-30.4/95-11-110. The substance was that ITU Q5/8, ITU Q7/14 and TIA TR-29.2 had all been involved in the content and in the overlap between draft V.25ter Annex A and draft Annex C/T.31. It is the current TR-29 position that SG 8 should abandon draft Annex C/T.31 in favor of draft Annex A/V.25ter. Draft Annex A/V.25ter has been determined for Resolution 1 decision in March 1995, but the work is not done. At WP 1/14, material was drafted and added to support V.8bis negotiation controlled by the DTE; it was presented in TR-30.4/95-11-111 (same as WP 1/14 document TD-83). This work is immature, and judged to need attention at TR-30.4 and at the upcoming Q7/14 Rapporteur’s group meeting (November 27-30). B. O’Mahony (Intel) prepared a thorough critique of TD-83 (New Annex A/V.25ter) in TR-30.4/95-11-107. It contains 35 items, and was presented and discussed in great detail. Agreements were reached on several items. The editor prepared a new version, TR-30.4/95-11-111R1, embodying many of these agreements. Other items were not resolved, and were listed as open issues. No consensus was reached on some of the proposed changes, so this did not result in a TR-30.4 position. The editor will capture what he can, and make a contribution to the Q7/14 Rapporteur’s group meeting (November 27- 30). OTHER BUSINESS: USB COMM DEVICE SPECIFICATION

TR-30.4/95-11-112, Snapshot of Universal Serial Bus Communications Device Class Specification, was distributed for information and comment. Comment should be directed to J. Decuir, [email protected]. It was not discussed due to lack of time. Joe Decuir, Microsoft

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TR-30 MEETING ROSTER, NOVEMBER 13 – 17, 1995, ORLANDO, FL Dick Brandt, dB Consulting Chair, TR-30 Les Brown, Motorola ISG Chair, TR-30.1 Fred Lucas, General Datacomm Chair, TR-30.2 Jack Douglass, Sierra Semiconductor Chair, TR-30.3 Jay Bain, UDS-Motorola Chair, TR-30.4 3Com John Rosenlof 3Com Richard Williams AMP George Lawrence AT&T Bahman Barazesh AT&T Dick Brandt AT&T Ken Ko AT&T Ed Zuranski AT&T Consumer Prod. Don McClarren AT&T Paradyne Domenick Ginex AT&T Paradyne Bill Girtoa AT&T Paradyne Bob Scott AT&T Paradyne R.K. Smith Bell Mobility Cellular Brian Smith Bell South Cellular Megan Klenzale Bell South Telecom. Bill McNamara Bellcore Ricardo Perez Compaq Computers Edward Newman Consultronics Jocelyn Doire Datarace Les Staples DEC Remi Lisee Digi International Ham Mathews Ericsson Al Sacuta General DataComm Emil Ghelberg General DataComm Yuri Goldstien Hayes Dave Rife Henderson Coms. Labs Warren Henderson IBM Ali Sadri Intel Chris Hanson Intel Barry O’Mahony Microsoft Joe Decuir Multi-Tech R.S. Gopalan National Semi. John Goldie Penril Datacom Dick Stuart Racal Datacomm Veda Krishnen Rockwell Glen Griffith Rockwell Joe Hoang Rockwell Ramin Nobakht RSA/Cirrus Logic Michael Apadula RSA/Cirrus Logic Karl Nordling Sony Andy Dao TAS Mike Pellegrini Telebit Ken Jones Texas Instruments Kevin Gingerich TIA Roberta Breden US Robotics Bryan Anders US Robotics Jonathan Hall US Robotics Andy Norell US Robotics Valimir Parizhsky US Robotics/Meghertz Wayne Park

December 1995 Vol. 6.8 Copyright © CSR 1995 37 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF SG 15 TRANSMISSION SYSTEMS: WP 1, AUDIOVISUAL/MULTIMEDIA WP 2, VOICE PROCESSING AND OPERATION FUNCTION NOVEMBER 14 – 22, 1995, GENEVA, SWITZERLAND Temporary document references include TD## for those of either Working Party 1 or 2, TD##(P) for those of Study Group 15 plenary, and TD##(G) for those shared between WP 1 and WP 2. A joint meeting of WP 1 and WP 2 took place in which harmonization of protocol activities between the two WPs, future structure of AVMMS (AudioVisual and MultiMedia Services) studies, and G.723 related issues were discussed. GLOBAL INFORMATION INFRASTRUCTURE (GII) The TSAG decided in September 1995 to set up a Task Force to work on GII (Global Information Infrastructure) under the leadership of SG 13. A joint meeting of this Task force will be held in Geneva February 17-19, 1996. TD-20 (P) includes an initial document from SG 13 which suggests an approach to GII standardization, delineates a work plan across the Study Groups, and makes suggestions for a framework for the GII. MIGRATION TO FPLMTS/IMT-2000 TD-38 is the draft report on the evolution to FPLMTS/IMT-2000 from ITU-R Task Group 8/1. It contains considerable detail on direction and existing wireless systems in use world-wide. SG 15 WP 1, AUDIOVISUAL/MULTIMEDIA The official WP 1 meeting report is contained in TD-65(P), and all outgoing liaison statements (LS) are contained in TD-67(P). The following WP 1 draft Recommendations were decided by SG 15. If reservations are removed, they will all go into postal ballot with approvals expected in about 5 months. NEW WP 1/15 RECOMMENDATIONS RELEVANT TO PSTN, B-ISDN, AND LAN MULTIMEDIA

• H.324 Terminal for low bit-rate multimedia communication (6-week reservation by the US) - COM-15-162 and TD-44(P) • H.223 Multiplexing protocol for low bit-rate multimedia communication (6-week reservation by the USA) - COM-15-164 and TD-45(P) • G.723.1 (previously G.723 but changed at this meeting to avoid confusion with an obsolete speech coding Recommendation) Dual rate speech coder for multimedia communications transmitting at 5.3 and 6.3 kbit/s - COM-15-153 and TD-28(P) • H.263 Video coding for low bit-rate multimedia communication - COM-15-159 and TD-29(P) • H.245 Control protocol for multimedia communication (6-week reservation by the USA) - COM-15-155 and TD-58(P) • H.321 Adaptation of H.320 visual telephone terminals to B-ISDN environments - COM-15-157 and TD-49(P) • H.322 (ISO/IEC 13818-1) Visual telephone systems and terminal equipment for local area networks which provide a guaranteed quality of service - COM-15-158 and TD-17(P) • H.222.1 Multimedia multiplex and synchronization for audiovisual communication in ATM environments - COM-15-156 and TD-47(P) REVISED WP 1/15 RECOMMENDATIONS RELEVANT TO N-ISDN MULTIMEDIA

• H.320 Narrowband visual telephone systems and terminal equipment - COM-15-151 and TD-48(P) • H.231 Multipoint control units for audiovisual systems using digital channels up to 1920 kbit/s - COM-15-160 and TD-3(P) • H.242 System for establishing communication between audiovisual terminals using digital channels up to 2 Mbit/s - COM-15-154 and TD-30(P) • H.243 Procedures for establishing communication between three or more audiovisual terminals using digital channels up to 1920 kbit/s - COM-15-161 and TD-75(P)

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WP 1/15 DETERMINED DRFATS The following draft Recommendations were Determined, will be edited further, and will come up for decision at the May 1996 meeting of SG 15: • H.310 Broadband audiovisual communication systems and terminals - TD-46(P) • H.225 (was H.22Z) Media stream packetization and synchronization for visual telephone systems on non- guaranteed quality-of-service LANs - TD-76(P) • H.323 Visual telephone systems and equipment for local area networks which provide non-guaranteed quality of service - TD-77(P) • H.222.0 (Amendments) Systems aspects for moving pictures (= MPEG-2) - TD-72(P) • H.262 (Amendments) Generic coding of moving pictures (= MPEG-2) - TD-71(P) • G.723.1 (silence compression[Annex A], floating point[Annex B] and enhancement of G.723.1 for mobile/PSTN) - TD-14(G), TD-15(G), and TD-16(G) respectively LBC GROUP WORK AND FINALIZATION OF PSTN MULTIMEDIA RECOMMENDATIONS

The report of the LBC experts group was presented by R. Schaphorst (Rapporteur for Very Low Bit Rate Visual Telephony) in TD-35 (see reort in this isue of CRT-T). All that is needed to make a PSTN videophone, or a voice+data terminal, was ready for adoption (H.324, H.223, H.245, G.723.1, and H.263). On the mobile PSTN front, work was progressing well: an annex for G.723.1 dealing with error control was put up for determination, (TD-16(G)), although WP 1/15 reserved the right not to use this annex unless the system eventually adopted calls for this particular solution. H.324 was presented by the Editor, D. Lindbergh (PictureTel). The input version was COM-15-162. TD-28© contains a version in which the essential session-selection protocol V.8bis and reception of silence frames are ex- plicitly mandatory. After some discussion as to the best way to cope with the fact that V.8bis has not yet been finalized in SG 14, it was decided to let V.8bis remain an option on the basis that, once it is stable, every implementer would probably include it. A few minor changes were made; all changes are noted in TD-44(P). TD- 69© is the complete final draft dated 11/20/95. H.324 was decided, but with a 6-week reservation by the US on IPR grounds (see H.223 below). H.223 was presented by the Editor, V. Eyuboglu (Motorola). A few minor changes were made, which are listed in TD-45(P). H.223 was decided, but with a 6-week reservation by the US on IPR grounds. In this regard, BT declared its patents not to be essential to H.223, but they are willing to review any written technical case to the contrary. H.263 was presented by the Editor, K. Rijkse (KPN). TD-52 (BT Labs) is a tutorial discussion of HRDs (Hypothetical Reference Decoder) and the need to make change to the existing H.263 HRD; this was supported. Other smaller refinements are listed in TD-29(P). H.263 was decided. G.723.1 (slight change of number to avoid confusion with a previous but now obsolete Recommendation) was presented by the Editor, R. Cox (AT&T). A few minor corrections were made and noted in TD-28(P). G.723.1 was decided. Recent revisions to H.245 were presented in TD-15(P) by M. Nilsson (BT), one of the editors. At the request of the February 1995 meeting of WP 1/15, the previously separate control protocols for B-ISDN (H.245) and PSTN (H.246) multimedia had been harmonized into a single document, and the protocol was expected to achieve even wider applicability by adoption for LAN multimedia systems (H.323) and V.dsvd. Many delegates complimented the experts groups and particularly the two editors (M. Nilsson and B. Welsh, BT) for this achievement. The extra editing and refinement caused by the H.245/H.246 merging had resulted in a large number of changes appearing in the document presented. SG 15 was sympathetic to this, and H.245 was decided, albeit with a 6-week reservation by the US on grounds of the need to study the late changes. A proposal in D.624 (J.-P. Blin, France Telecom) concerning mode preference source identification was considered a useful input for future enhancement of H.245 for multipoint working. AVC GROUP WORK AND FINALIZATION OF B-ISDN AND LAN MULTIMEDIA RECOMMENDATIONS

The report of the AVC (Audiovisual Conferencing) group was presented by S. Okubo (Rapporteur for Q2/15, Videoconferencing and Videophone) in TD-37. TD-36, the H.310 hardware trial notes that the core part of draft H.310 has been verified by hardware experiments in Japan.

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Enhancements to cope with H.323 requirements were incorporated into H.245. H.245 applies to B-ISDN and LAN multimedia systems as well as to PSTN systems. TD-38 from the Q2/15 proposed the additions to H.245 to meet the H.323 requirements. H.310 (Broadband Audiovisual Communications Systems and Terminals) had a few minor changes made to the latest input version (TD-72, see changes in TD-33), and the result was determined at the SG 15 Plenary. H.310 is seen as overlapping the non-conversational system specified in the DAVIC (Digital Audio-Visual Council) project. For this reason, it had been deferred for determination from the February 1995 meeting, and every effort has been made to ensure complementarity. Thus, H.245 was called upon to deal with in-band control for conversational applications and DSM-CC (Digital Storage Media - Command and Control) for non-conversational. The call control aspects, although having rather different characteristics in the two areas, are also aligned where relevant. Further textual refinement of H.310 is planned to take place at the next Rapporteurs meeting in January. Technical editor’s note: DSM-CC is a set of protocols intended to provide the control functions and operations specific to managing ISO/IEC 11172 (MPEG 1) and ISO/IEC 13818 (MPEG-2) bitstreams. WD-1 is ISO/IEC 13818-6 Part 6 of ISO/IEC 13818 extension for DSM-CC Committee draft ballot. H.321 is the adaptation of H.320 visual telephone terminals to B-ISDN environments. Minor changes were made to the input version, COM 15-157, as reported in TD-49(P). It was decided at the closing SG 15 plenary. H.322 (ISO/IEC 13818-1) is the visual telephone systems and terminal equipment for local area networks which provide a guaranteed quality of service. On the basis of COM-15-158 and TD-17(P), H.322 was decided at the opening SG 15 plenary . H.323 (TD-30) is the visual telephone systems and equipment for local area networks which provide non-guaranteed quality of service. After extensive productive discussion, a version for Determination was produced in TD-77(P). Further refinement, notably in the area of call control, was planned to take place at the next Rapporteurs meeting in January. H.225 (formerly H.22Z) is the media stream packetization and synchronization for visual telephone systems on non- guaranteed quality-of-service LANs (TD-76(P)). After further editing it was put up for determination. It was granted, although SG-15 had some misgivings about the number of points marked for further study and the experts will have to use their skill and judgment to minimize the appearance of changes for the May meeting. •H.222.0 (ISO/IEC 13818-1), systems aspects for moving pictures, had some amendments arising from MPEG-2 work and was determined in TD-72(P). TD-49 provides the amendments regarding the registration and copyright identifiers which were finalized at a recent MPEG meeting. H.222 specifies a unique 32 bit copyright identifier (e.g. ISBN, ISSN, ISRC, etc.); this amendment describes the procedures used to obtain a registration identifier. H.222.1 is the multimedia multiplex and synchronization for audiovisual communication in ATM environments. Minor changes were made to the input version, COM-15-156, as found in TD-47(P). It was decided at the closing SG 15 Plenary. H.262 (ISO/IEC 13818-2), the generic coding of moving pictures, also had some amendments arising from MPEG-2 work. It was determined in TD-71(P). TD-50 provides the amendments regarding the registration and copyright identifiers which were finalized at a recent MPEG meeting. TD-51 contains two technical corrigenda to H.262 which SG 15 intends to approve together at the May SG 15 meeting. TD-2 a liaison from SG 9 includes a copy of draft Recommendation J.82 (decided), Transport of MPEG-2 constant bit rate television signals in B-ISDN. The liaison notes that J.82 covers transport of television signals to the end user and is in line with Recommendations H.222.1 and H.310. TD-14 is a liaison from ISO/IEC JTC 1/SC20/WG 11 (L. Chiariglione, Convener) which includes a copy of the Committee draft ballot ISO/IEC 13818-9 extensions for real time interface for system decoders. The liaison asks for continued collaboration with SG 15. REVISION OF NARROWBAND ISDN RECOMMENDATIONS

H.231, multipoint control units for audiovisual systems using digital channels up to 1920 kbit/s, was decided at the opening SG 15 Plenary as COM-15-160 with minor editorial corrections described in TD-3(P). H.243 is the Recommendation on procedures for establishing communication between three or more audiovisual terminals using digital channels up to 1920 kbit/s. With minor changes as described in D.475 (US), TD-4(P),

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and TD-44, H.243 was decided as COM-15-161. The main enhancement from the 1993 version is the picture- composition facility for “continuous-presence” multipoint. In response to a request from the T.120 group in TD- 47 to solve the problem of stimulating MLP (Multi-Layer Protocol) channel rate changes from a terminal using BAS (Bit-rate Allocation Signal) codes, it was decided to define a mode-preference code in H.230 leading into a table of rates listed in H.243. TD-16 a liaison from SG 8/Q10, provides a copy of T.128 (T.avc, audio visual control). T.128 is applicable across a range of networks including those supported by H.243. Q10/8 sees T.128 providing enhanced functionality to optional parts of H.243. H.242, the system for establishing communication between audiovisual terminals using digital channels up to 2 Mbit/s, was decided as COM-15-154, with changes described in TD-30(P), taking into account: • Tightening of the definition of Capabilities • Commands after Sequence A must now be from Table A.1/H.221 • Strengthening of text about sending commands before Sequence A, caution about freezing G.728 decoder during delay insertion, clarifying text concerning order within capability sets (All of these are intended to reduce the chance of bad audio conditions at the start of videophone calls.) • Clarification of the mode-preference procedure, including MLP rate control H.263 capabilities for H.320 were not included in the present revision since further study of the exact formulation is needed. H.320, narrowband visual telephone systems and terminal equipment, was decided as COM-15-151, with minor changes described in TD-48(P). There were several contributions concerning the future addition (not in the 1995 revision) of G.723.1 audio, H.262, and H.263 video as options into H.320: • COM-15-224 (US) • D.535 (D. Skran, AT&T, US) • D.664 (I. Sebestyen, Siemens) • D.665 (N. Kenyon, BT). H.263 had been shown to provide a very significant improvement over H.261. It had been a policy decision in WP 1/15 some years ago not to put other algorithms into H.320 until a notable improvement was offered, and even then to insist on backward compatibility. H.262 is better than H.261 only at higher rates, but has advantages for applications other than pure videotelephony. It deals with interlace, has more flexible frame dropping, can be run in reverse, etc. The 1995 version of H.221, Frame Structure for a 64 to 1920 kbit/s Channel in Audiovisual Teleservices, was approved by postal ballot on July 24. A further revision is planned for about two years hence. Certain aspects were frozen for immediate implementation: • Changes requested by SG-9 in TD-29 for dealing with broadcast audio channels on restricted networks, • A reply (LS-9) containing further advice related to the desirable cross reference to H.242 that should accompany this enhancement, • clarification of H-MLP-14.4k, and esc-CR as defined - no longer just reserved. It was agreed that H.221/230 revision documents would not contain any references to H.262, H.263, and G.723.1, but that the US would circulate its revised proposals (taking into account other viewpoints expressed) to Q3/15 cor- respondents by the end of February, in order to reach a consensus for freezing in May 1996. The 1995 version of H.230, Frame Synchronous Control and Indication Signals for Audiovisual Systems, was approved by postal ballot on July 24. A further revision is planned for about two years hence. Certain aspects were frozen for immediate implementation: codepoints VIN2, VIC, VIM, MIH, NIR, and the mode-preference indicators for audio, video, and MLP_rate and clarification of TII, NIA-s and TIP. COM-15-234 details a number of options for dealing with the character set in H.230 that can no longer be specified with reference to T.61. It was decided to replicate the necessary specification material from T.61 within H.230 itself without any changes. Suitable extension to H.230 could be made in the future if there is demand for other sets such as ISO-8859.

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Q3/15 MULTIMEDIA HARMONIZATION

SIMULTANEOUS VOICE AND DATA SYSTEMS

TD-25(G) and TD-23(G) from WP 1/14 report on SG 14’s work on this topic. Concern was expressed that the problem of the multiplicity of PSTN multimedia platforms with overlapping functionality had worsened since July, when the Joint Coordination Group (JCG)/AVMMS had requested that all involved should seek to ameliorate the situation. Not only had the V.34Q proposal appeared on the scene, but also suspend/resume had been added to V.gmux. It was also thought that the V.34Q held considerable promise, and a reply (LS-2) to WP 1/14 encourages this work. TD-4, TD-18, and TD-24(G) are liaison statements from WP 1/14 concerning the speech coding G.dsvd planned for use with V.dsvd. From the Q3/15 point of view, it was regretted that the speech coding used in H.324 had not been chosen, since it offered adequate performance at a slightly lower bitrate and the prospect of better harmonization among multimedia terminal systems. TD-12(G) and TD-20 are liaison statements from SG 8 regarding support of facsimile-plus-speech systems; TD-6 is a liaison statement from SG 14 commenting on the issues regarding SVF (Simultaneous Voice and Facsimile). A reply was prepared (LS-10) notifying the inclusion in H.245 of the T.84, T.434, and T.120 codepoints requested. Furthermore WP 1/15 offered to include one for T.30, so that any of the several systems for PSTN using H.245 will naturally be able to carry T.30 facsimile. GENERAL MULTIMEDIA SERVICE

TD-11 (SG 1 draft F.GMM, General Multimedia Service for ISDN), TD-12, TD-19, and TD-26 are ongoing correspondence between SG 1, SG 8, SG 11, and SG 15 concerning a “general” multimedia communication service on ISDN. This scheme enables a multimedia terminal to make an ISDN call without first deciding whether the call is to be conversational, storage/retrieval, messaging, etc. Any appropriate terminal may answer the call, and by means of exchanges in H.221/242 and/or T.90 (extension being made in SG 8), a suitable session according to user needs and equipment capabilities is initialized. This may be H.320 videotelephony, telephony, T.120 multimedia (with or without speech), facsimile, videotex, documents, etc. Furthermore, mid-call changes between conversational and non-conversational sessions can be made. TD-32 (N. Kenyon BT Labs), the first draft of a new Rec. H.mmiw (multimedia interworking), addresses the procedures required. A liaison (LS-7) to the other SGs informs them of this, pointing out that the service definition must be such that other terminals not having both con- versational and non-conversational capabilities must nevertheless respond to a call request containing the general “multimedia” HLC (Higher Layer Compatibility) codepoint. Discussion on TD-32 pointed to the need for a more general approach, which would encompass a much wider range of interworking situations and take into account all the network types. It was agreed to modify the scope and structure of the draft Recommendation to show this wider compass without, at this stage, putting more than a few initial notes in the proposed new sections. The content of this new draft was not approved in detail or frozen in any way, but it will serve as a basis for a much improved Interworking Recommendation for the next meeting. Furthermore, it was hoped that this document could be the focus of attention of an interim correspondence that would consider other related material known to the group. OTHER HIGHLIGHTS

TD-17(G), from SG 2, requests advice concerning multilink PSTN multimedia. The reply, TD-67A1(P), informs SG 2 that the first version of H.324 is single link but has hooks for multilink that will be under study for the enhanced version and that there is still time to take into account any concerns SG 2 may have. More guidance was sought on certain points of detail. TD-10 from SG 9, gives information about terminology for . The response, TD-67A6(P), suggests that the term “interactive” might be confusing (e.g., versus conversational) and suggests a note be added. TD-25 is a liaison from SG 11 replying to a request to review the JCG/AVMMS report. It notes that reference to Q.939 and Q.2939 in the Framework for Multimedia Recommendations should be to Q.931 and Q.2931. However, it was felt that both Q.931 and Q.939 contain material specific to videotelephony, that visibility of these should be retained, and that the documents be taken into account in the “General Multimedia” interworking studies.

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TD-3 is a liaison statement from ISO/IEC JTC 1/SC6 WG 6. It invites review and comment on the attached June 19 version of ISO/IEC-13871, Information Technology - Telecommunications and Information Exchange Between Systems - Private Telecommunications Networks - Digital Channel Aggregation and shows alignment with H.244 work following earlier correspondence. A reply TD-67A4(P) expresses appreciation and a minor editorial point. TD-7 is a liaison reply from SG 14 on dataport for videotelephones. TD-42 is a liaison statement from SG 14 providing a status report of the work on Annex B/V.25ter, Synchronous Data Modes, and draft Recommendation V.ib. TD-17 is a liaison statement from SG 8 stating that Q10/8 has undertaken the work of drafting an Appendix for the next revision of T.123 to suggest how the data protocol stacks specified in the body of the Recommendation may be accessed through the kind of serial dataport that is found in most personal computers. It was felt that work in SG 14 appeared to be progressing according to WP 1 needs, and suitable specifications could be expected to be produced in due course. No further action was required. TD-13 is a liaison statement from SG 1 seeking comments on the mobile multimedia service description. Comments were returned in TD-67A8(P). TD-23 is a liaison statement from SG-13 requesting comments on a draft baseline document addressing network issues for multimedia services with tables of properties/requirements. This is derived from the EURESCOM Project P404 and lists four categories of multimedia services, videotelephony, games, teleshopping and video-on-demand. Errors and omissions were noted, but since it was not clear how this document would advance the specification of infrastructure systems, it was decided not to send a detailed reply at the current time. STUDY QUESTIONS FOR THE NEXT ITU STUDY PERIOD The preparation of Study Questions for the new study period (1997 to year 2000) was started; it is particularly important, since consideration is being given to bringing together much of the Multimedia middle-layer studies by means of a Joint Working Party, new/changed Study Group, Task Force, or other device. It was agreed that a useful way to map out the study work covering the whole multimedia area would be on the basis of a matrix (Matrix 1). It was seen that Questions A, B, C, and D are oriented to groups of networks having fairly similar characteristics, while the orthogonal Questions X, Y, and Z are of a kind addressing topics pertinent to several or all the columns. It was believed that such a scheme would provide a good basis for management and review by WP 1/15, and that by good collaboration Question A: Very Question B: Question C: Question D: LAN low bitrate MM N_ISDN MM B_ISDN MM MM systems systems systems systems

Question X: Harmonization & Interworking of MM Apps & Sv. Question Y: MCUs, Control Question Z: Advanced coding Matrix 1. Proposed Map of ITU Multimedia Work Areas. between the various Rapporteurs, any conflict of responsibilities could be resolved. Full details are contained in TD-66(P), but some points of general interest were: • The various system columns take care of conversational and non-conversational applications • Each column has work that is not common with other columns, and much Recommendation drafting would be columnar, as at present • “Control” includes such aspects as security, in-band management, call control interworking, etc. The draft Questions will be refined prior to the May 1996 meeting. Input to this process is welcomed. JCG/AVMMS COM-15-169 (BT) argues against the adoption by the ITU of conflicting Recommendations covering audio+data systems, on the grounds that there is insignificant difference in overall delay, and other differences are minor.

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The Chair, M. Yamashita (NTT), reported on the TSAG (Telecommunication Standardization Advisory Group) deliberations concerning the future management of ITU multimedia studies and provided discussion material in TD- 19(G), TD-20(G), and TD-21(G). These note three inputs for discussion: • A Canadian proposal to abolish JCGs and have better coordination via joint meeting of Working Party leaders and Rapporteurs. • A US proposal to have a Study Group for AVMMS • A proposal for the meeting of SG Chairs to consider the establishment of “task forces” which have the power to create Recommendations. Related proposals were made in D.481 (Siemens, see also D.481R1) for a Joint Working Party, in TD-10(P) (Q3/15 Rapporteur) for consolidation of all SG 15 multimedia work into WP 1/15, and in TD-22(G) (WP 1/14 Chair) for a Joint Rapporteurs’ activity. Members were encouraged to input their views to the JCG/AVMMS via M. Yamashita as soon as possible. Norman Kenyon, BT Labs

SG 15 WP 2, VOICE PROCESSING AND OPERATION FUNCTION

Q4/Q8 ALGORITHMIC TECHNIQUES IN VOICEBAND TELECOMMUNICATIONS NETWORKS/INTERACTION OF FACSIMILE AND HIGH SPEED VOICEBAND DATA WITH ALGORITHMIC PROCESSING IN VOICE NETWORKS.

TD-8, the report of the experts meeting in Washington DC in September 1995, includes in Appendix II a discussion of the requirements and applications for PSTN support of multi-media terminals (from an original document by AT&T). This opens up the issue of terminal-to-network channels distinct from terminal-to-terminal channels. A discussion took place on the interaction of voice activity detection algorithms with network signal processing equipment. These algorithms would provide robust operation in noisy acoustic environments that differs from the environment in which the traditional network speech detection algorithms operate for echo cancellers, DCME/PCME. It was agreed that some background/tutorial information that cannot be captured in a recommendation, but that may be needed in the future, should be maintained. Work continued on the draft text of G.fax-test, Test Methodology for G3 Facsimile Processing Equipment in the PSTN. This draft provides tests to determine effects of the signal processing equipment within the network on G3 facsimile (and data modems) traffic. The draft of G.fax-test coming into the meeting is in Appendix I of TD-8 2/15. An editorial team led by France Telecom created TD-73 as the revised version of G.fax-test. Draft G.fax-test also includes a section (11.6) on voice band data quality utilizing V.32 modems. Agreements were made on control channel requirements (terminal to/from network signaling) in support of multimedia terminals and protocols. It was agreed (in TD-8) that the signaling protocol could be based on Q.931, T.120, the MCU suite of protocols or some adaptation of other existing protocols. An initial proposal (TD-72) based on Q.931 was presented to advance the work. TD-92 is a liaison from Q4&8/15 to SG 14 that offers to exchange information on the various issues related to V.dispatch. Attachment I includes Q4&8/15’s thoughts on the development of a one octet CRC (for V.gmux); Attachment II (copy of TD-53) includes draft Recommendation G.mmpp (multi-media packet protocol) which uses a UIH frame for the transport of voice that was proposed at an experts meeting in Washington, DC September, 1995. The control function, while not defined in this document, could be based on Q.931. TD-92 also suggests that the current version of V.gmux needs to be modified to take into account the use of UIH frames for voice traffic. Q5/15 VARIABLE-BIT RATE EMBEDDED OPERATION FOR LD-CELP

TD-74 (S. Hayashi, NTT) is the Rapporteur’s report. At the Montreal meeting in June 1995 the extension of 16 kbit/s LD-CELP (Annex I of G.728) for robust operation against frame-erasure condition was not approved as it did not pass under one condition in one language. Several possible direction were discussed, but no new papers to further this work were presented to this meeting Mitsubishi presented the text for the draft Annex H of G.728 for variable bit rate operation below 16 kbit/s (D.580). Mitsubishi also presented the digital test sequence (D.581) to verify that the algorithm is correctly implemented. The host lab for variable bit rate operation below 16 kbit/s is Deutsche Telekom. The char-

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acterization subjective tests will be available at the SQEG expert meeting of February 1996. COMSAT kindly responded to the request for the characterization tests of DTMF. D.662 (MOC, Israel) is a new algorithm for the variable bit rate operation of LD-CELP for voice-band data applications at rates greater than 16 kbit/s. The terms of reference for this DCME requirement are in Annex A of TD-74. Preliminary subjective and objective tests seem to indicate that the algorithm could meet the requirements, except for that of speech quality dependency. Utilizing V.34 Supra 288 modems, the test indicate that the algorithm is capable of transmitting V.34 signals of 21,600 bit/s. The general degradation caused by the algorithm is one or two V.34 rates lower (e.g., 19,200 to 16,800, etc.). The requirements were changed to make them consistent with the requirements on other coders. There was concern that the algorithm presented was significantly different than the algorithm previously presented at the meeting of the experts in Munich in October 1994. MOC promised to submit the high-level description of the algorithm in February 1996 so that the testing phase could start. SG 12 will be asked to draft the subjective test methodology. Q6/15 AUDIO AND WIDEBAND (7 KHZ) SPEECH CODING IN PUBLIC TELECOMMUNICATIONS NETWORKS

The Rapporteur’s meeting report is TD-75 (R. DeIacovo, CSELT) . The terms of reference for wideband coding (Annex A TD-75) were revised to include additional degradation figures for detected frame erasures conditions. The coder is to have two modes: Mode A is a low-delay and high-complexity coder. Mode B is a high-delay low- complexity coder. Each coder has 3 bit rates 16, 24 and 32 kbit/s. A correspondence group will prepare a qualification test plan by June. The deadline for submission of a candidate is September 1995. The completion date for the draft recommendation was advanced to July 1997. Candidates are to be presented in February 1996 and hardware models shall be provided by the proponents. A revised subjective qualification test plan, based on TD-56, will be available at the anonymous ftp address ftp.std.com at the directory vendors/PictureTel/sgp15_q6. D.527 (PictureTel), the US contribution on the need to consider reverberation (spacing of 3 to 10 feet between the microphone and speaker) in wideband codec testing, was accepted. The meeting decided that there was not sufficient knowledge to fix the controllable requirements, and the change in the terms of reference only requests comparable performance to G.722. However, codec providers will be required to provide, for the qualification phase, a demo tape containing speech samples in reverberant conditions. Q7/15 ENCODING OF SPEECH AT BIT RATES AROUND 4 KBIT/S

TD-81 (G. Schroeder, Deutsche Telekom) is the Rapporteur’s report. The terms of reference for a new toll-quality 4 kbit/s voice coding algorithms were revised by elaborating the requirements specification for the random frame erasure condition, the delay condition and the background noise condition. Candidate proposals are expected by the May 1996 SG 15 meeting. TD-82 is the new terms of reference. TD-24 (Telenor, CNET, Deutsche Telekom) provides the subjective test plan created in cooperation with SG 12/SQEG. During the meeting some improvements were added. The revised test plan is TD-83. To receive an electronic version, e-mail [email protected] with the contents “send-q7-test-plan” only. Q9/15 SPEECH PACKETIZATION AND WIDEBAND PACKET SYSTEMS

TD-68 (D.K. Sparrell, AT&T) is the Rapporteur’s report. SG 15 decided Appendix 1 (Packetization Guide) G.764, Voice Packetization - Packetization Voice Protocols, and Appendix 1 (Guide to PCME) G.765, Packet Circuit Multiplication Equipment. The texts of the draft TMN Recommendations were advanced: • G.sparm (SPTT Managed Objects) TD-32 • G.snem (SPTT Network Element Manager) TD-31 • G.cmif (SPTT configuration map interchange format) TD-33. (SPTT = Signal Processing Transmission Terminal) The goal is to complete these Recommendations at an interim meeting (Spring 1996) and continue work on G.print. Q10/15 SOFTWARE AND HARDWARE TOOLS FOR STANDARDIZATION OF SPEECH AND AUDIO CODING ALGORITHMS

The text of G.192 (COM-15-150), A Common Digital Parallel Interface for Speech Coding Standardization Activities, was agreed for decision. PKI/Germany contacted the Rapporteur, confirming that they claim no IPR on G.192. The software tool library was updated, TD-27(P)© is the new revision of Annex A, the list of software tools

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available. The new document is Evolving Software Tools Library, Release of November/95 (eSTL9511), and is available by request to the Rapporteur to ITU members. The text of the current version of the Software Tools Library Manual is TD-69. Q11/15 EQUIPMENT FOR STORED AND DIGITIZED CODED INFORMATION

There were no contributions. This question will be dropped at the next study period. Q12/15 ENCODING OF SPEECH AT BIT-RATES AROUND 8 KBIT/S G.729 TD-79 (G. Schroeder, Deutsche Telekom) is the Rapporteur’s report. G.729 (COM-15-152), Coding of Speech at 8 kbit/s using conjugate-structure algebraic-code-excited linear-prediction, was decided by SG 15. In the future, additional algorithmic features of interest will be pursued: floating-point version, a voice activity detection algorithm, lower bit rate extensions (D.541 from NTT proposed 6.4 kbit/s), and a variable bit rate extension. Attached to TD-79 is a paired comparison test for verification of fixed-point/floating point interoperability. D.511 from BT proposes to utilize the VAD algorithm defined for GSM (ETS 300-580-6, full rate and ETS 300-581-6, half rate) as the basis of the G.729 VAD. TD-48 from the SQEG Chairman presents the results of the channel degradations tests on G.729 from CSELT. TD-49 (Deutsche Telekom/FTZ) describes three optional tests performed to characterize the subjective performance of G.729. The tests were: • Interworking with other wireless and transmission standards, • Effect of environmental noise, • Effect of channel degradations. TD-66 (SQEG, prepared by AT&T) provides the results of similar tests from BNR, FT/CNET and BT. In summary, the results from the three papers show that the final version of G.729 fulfills the requirements. TD-64 is a list of organizations (99) that have received G.729 C source code. G.729 performance characterization for network signaling tones and DTMF results were not available. Results from tests by COMSAT test facilities and a hardware implementation from the host lab of Deutsche Telekom will be made available in February. Currently only AT&T has provide the Rapporteur with a list of their IPR related to G.729. TD-6 is a liaison from ITU-R Task Group 8/1 noting their interest in G.729 work. They request to expand the test condition to include 3% frame erasure. This liaison raises several more issues and includes a draft of Annex C FPLMTS.REVAL, Test environments and deployment models. G.DSVD

TD-69 is the report of this meeting by the G.dsvd Rapporteur J. Magill (AT&T UK). TD-30 is the final report from COMSAT Labs which indicates that the DSP Group was the only coder to meet the terms of reference. D.543, Report about the host lab processing (NTT), and D.544, Report on the subjective tests of candidate codecs for DSVD (NTT), provide background information to the test results. TD-18(G) is the report of the work coming into this meeting and includes draft specifications of the University of Sherbrooke and DSP Group vocoders. Selecting between the two coders for SG 14 DSVD applications was the most controversial part of the SG 15 meeting. The University of Sherbrooke vocoder is G.729-based and can interwork with full G.729 coders (bit stream compatibility). The data rate of the University of Sherbrooke coder is 7.9 kbit/s which could fit easily into a 8 kbit/s transport mechanism such as specified by H.221. The DSP Group vocoder is 8.8 kbit/s and G.723-based, making it simpler for H.324 implementors to utilize. TD-59 includes a contribution from an interim G.dsvd meeting by PictureTel. It provides a discussion of their reasons for desiring a G.729-based/interworking vocoder (interworking: H.324 already supports G.729 as an option and such an option is likely for H.320 as well). Coming from a likely H.324 vendor, this paper was significant. Based on a suggestion from T. Irmer, the director of the ITU, a straw poll was conducted to assess the attitudes of the various organizations. Excluding the votes of the proponents, 20 organizations voted in favor of the University of Sherbrooke simplification of G.729 and 2 votes were cast in favor of the DSP Group/Audio Code algorithm. One of these two votes was from Siemens. The DSP Group’s representative Y. Be’ery claimed to control the Israeli vote

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and threatened to veto any proposed coder that did not include an intellectual property right from the DSP group. In an attempt to reach a consensus, an ad-hoc group was established to generate guidelines on how to merge the two coders by February 1996. The terms of reference would be the same as the original terminal references with G.729 interoperability required. Y. Be’ery proposed that the compromise coder should comprise as much code from G.723 as possible. Subjective tests will be run with two languages, and testing should include the original University of Sherbrooke coder. Under that compromise plan, there would be an interim working party meeting no later than mid- February to put the Recommendation for determination in time for the May SG 15 meeting. The proposal elicited long discussions and the participants felt that it did not address the following issues: • Who would participate in the joint work? • Should be it restricted to the original five participants or opened again to new submissions? • How to coordinate the work among the participants? • What guidance to give to the proponents? • How to resolve potential disputes? • Who would run the subjective tests? • Who would fund the testing? • Is there a possibility of having a working party meeting? NTT agreed to see if it could act as the test/host laboratory but it was not clear that they would have the resources available at the right time. However, the procedure to resolve potential disputes could not be agreed. There was a strong sentiment among the participants that the University of Sherbrooke coder be the default coder if the compromise coder does not show significant improvements or if a consensus could not be reached in February. Y. Be’ery objected to that proposal. Siemen’s representative, in contrast, suggested that a coin be tossed to resolve any potential deadlock. At this point, the group felt that the probability of success was not high enough to warrant the execution of the proposed program, and the group settled on the coder proposed by the University of Sherbrooke. It was selected for determination as an Annex to G.729, to be decided under Resolution 1 procedures at the May/June meeting of SG 15. The DSP Group (Israel) was opposed, and BT expressed strong reservations concerning the need for the G.dsvd considering the speech coders already defined in videotelephony, e.g., G.723 in H.324. Q13/15 DIGITAL CIRCUIT MULTIPLICATION EQUIPMENT AND SYSTEMS

TD-97 (Y. Naito, Mitsubishi) is the Rapporteur’s report. Work on G.763 (TD-28), DCME using 32 kbit/s ADPCM and digital speech interpolation, and G.766 (TD-29), Facsimile demodulation/remodulation for DCME, and TD-29A1 (SDL diagrams for TD-29), continued with the purpose of seeking determination at this SG 15 plenary. D.579 (Mitsubishi), Modification of TCH (transparent circuit handling) process for the fake messages and the recovery from power down, describes the complete proposal for the modification of the TCH process in G.763 principally agreed at the Yokohama Rapporteur’s meeting, May 31-June 7, 1995. TD-99 provides the editorial corrections to G.763 (TD-28). TCH was the only point of contention with G.763 at this meeting. A compromise proposal was agreed by a drafting group but failed because a delay would be introduced in transparent call establishment. ECI (Israel) introduced a previous proposal made in Yokohama. This proposal is logical but requires large-scale modification that would delay the progress of inter-operability testing being conducted by INTELSAT, and the difference could not be resolved. G.763 determination was postponed to the next SG 15 meeting. This also delays G.766 which is ready for determination as the only changes made were editorial (changes in TD-98). The next meeting of this Question will be in March, 1996 with the joint Q4/15, Q8/15, Q9/15 and Q15/15 meeting in France. µ-Law Channel Test Vector was prepared by the Rapporteur (TD-25). ECI, NEC and Mitsubishi will evaluate the validity of this test vector. TD-43 is a reference liaison from L. Brown (Rapporteur V.8bis SG 14) on the use of V.8bis MS (mode select, a V.21 high band HDLC format) signal by CME. Q13/15 confirmed that all the current DCME cannot decode the V.21 signal without 2100 Hz occurring previously. Q14/15 DESIGN AND INTERACTION OF ACOUSTIC PROCESSING DEVICES

TD-4, liaison from SG 12, describes their work plan and the focus of their work on subjective speech quality. The work plan includes a draft Recommendation on general problems of AEC (Acoustic Echo Control) in 1997, and a draft Recommendation dealing with general speech enhancement devices in 1998. This liaison also proposed that the G.167 AEC work be split. TD-3, another liaison from SG 12, provides copies of P.sgn (draft Recommendation on test signals for use in telephonometry) and P.83 (draft revised Recommendation on Subjective performance

December 1995 Vol. 6.8 Copyright © CSR 1995 47 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS assessment of telephone-band and wideband digital codecs). Additional information on test signals is in D.477 (Deutsche Telekom), Starting point of the CSS (Composite Source Signal) for single and double talk measurements, and in D.566 (M. Givens, AT&T), CSS level measurement technique. Q14/15 agreed that G.167 will be split into terminal aspects of acoustic echo controllers, and separately, their interaction with the network. The terminal aspects will be the responsibility of SG 12. Thus, chapters 1-5 of G.167 will be included in a new P-series recommendation, and an improved chapter 6 will form the content of the revised G.167. Since the current chapter 6 contains only general information, more work will be needed in the new study period. TD-78 is the liaison to SG 12 describing this split. Q14/15 will be combined with Q15/15 in the next study period, with the focus of defining the interactions of acoustic signal controllers and network equipment. Q15/15 NETWORK ECHO CONTROL

Work continued on the development of recommendation G.IEC (improved echo canceller, an update of G.165), in particular to define the use of a composite source signal level measurement technique. Information on the composite source signal will be added as Annex C of G.IEC. TD-47 is the revised draft of G.IEC. D.480, Deutsche Telekom, provides draft Appendix A of G.IEC, Guidance for the Application of echo cancellers, a tutorial on the use of echo control. Discussions were on the following tests: Test No. Input Documents Description 1 D.483, D.567 Steady state residual and returned echo level test 2 D.478, D.500 Convergence test 3 D.479, D.501, D.663 Performance under conditions of double talk 6 D.502 Non-divergence on narrow-band signals 7 D.563, D.569 Stability test 9 D.503, D.565 Comfort noise test 11 D.485, D.562, D.568 Tandem echo canceller test 12 D.504 Residual acoustic echo test 14 D.505 Performance with ITU-T low bit rate coders in end path More results are needed on the convergence test and there was agreement on the way to present the results. Agreements were made on the tests for non-divergence on narrow-band signals, stability, comfort noise and on a recommended echo path for echo canceller testing purposes. It was agreed in principle to add a double-talk test (under the name of test 3d). Regarding the new techniques proposed by SG 14 such as V.8bis and framed QADM with V.34, it was not clear whether these new techniques would affect the network echo cancellers; there was insufficient time to fully discuss the topic. D.564 (M. Givens, AT&T, supported by the US T1A1 committee) notes the need for tests of echo canceller performance with low speed modems. D.570 (same author) explains in considerable detail the cause of low-speed data modem failures caused by interaction with echo cancellers. A joint meeting with Q4&8/15, Q9/15 and Q13/15 is planned for the Spring of 1996. Q16/15 SPEECH, VOICEBAND AND AUDIO TRANSMISSION IN ATM/B-ISDN SYSTEMS TD-105 (R. Montagna, CSELT, Italy) is the Rapporteur’s report. D.509 (UK) proposes that synchronous timing be maintained between transmitter and receiver voice codecs across an ATM network. If this is not possible, then alternative means are described to convey the timing information across the ATM network. Annex 7 of TD-68 (D. K. Sparrell, AT&T) is a discussion of efficient transport of ATM voice traffic on the PSTN and proposes an ATM to CME interface for this function. TD-18 (SG 13) indicates that SG 13 has reached agreement on the use of AAL1 for the support of CBR voiceband signals. The AAL will support this by providing synchronous service (neither SRTS [synchronous residual time stamp] nor adaptive clock is used) with single octet delineation (pointer is not used). All 47 octets of the AAL-PDU payload are used for the voiceband signal from a single source (i.e., cells are completely filled and the ATM virtual circuit supports a single voice band connection). Draft Recommendation I.363.1, B-ISDN ATM Adaption Layer (AAL) Specification Type 1 and 2, is attached to TD-18 for information. TD-9(G), another liaison from SG 13, reports that SG 13 is considering a study to develop a new AAL which supports more than one user information

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stream within one ATM cell payload. Possible applications include support for mobile communications where short length of fixed or variable data and low bit-rates are used. Time was not available to update the current draft of I.ATM-V. An interim meeting will be necessary to complete this work for determination in May 1996. Mid-February is proposed. Future work will include: • Efficient transmission facilities over ATM; • Signal Transmission Quality Monitoring; • Identification of interworking scenarios between fixed and mobile network systems and systems implemented using ATM technology. Q32/15 IMPACT OF TRANSMISSION CHARACTERISTICS ON MOBILE SATELLITE COMMUNICATIONS SYSTEM SIGNAL PROCESSING ASPECTS TD-85 (R. Smith, Inmarsat) is the Rapporteur’s report. No documents were submitted for this Question. It was agreed that channel error models that have been developed for existing Inmarsat digital mobile terminals should be modified to be compatible with the ITU common digital parallel interface as proposed in draft Recommendation G.HT. Since the last SG 15 meeting in February 1995, work has been completed on developing channel error models for all existing Inmarsat digital mobile satellite standards. Models now exist for Inmarsat-B (16 kbit/s codec), Inmarsat-M, Inmarsat Aero-H (9.6 kbit/s codec), Inmarsat Aero-I (4.8 kbit/s codec) and Inmarsat Mini-M (4.8 kbit/s codec). In some cases, these error models exist for more than one propagation condition (e.g., urban and rural). Currently these models exist only as serial bit error file format. It was agreed that these models should be further developed to represent errored channels compatible with the common digital parallel interface for speech and audio. NEW QUESTIONS TD-103 (M. Sherif, AT&T, Rapporteur for New Questions) provides draft text for new and continued questions for WP 2/15. It suggests the following significant changes: • Combine Q4 and Q8 and expand the scope of the new question to cover layers 2-4 aspects of the PSTN, LAN, cellular/mobile, ISDN and B-ISDN. Proposed title: Interaction of multimedia and high-speed voice-band data with signal processing equipment in the PSTN. • A new Question 9 which combines the TMN aspects of all PDH (packet data handling) signal processing equipment. • Combine all equipment aspects on DCME/PCME and VCLAD (voice cell assembly device) in the new Question 13. • Delete Question 11. • Combined Questions 14 and 15. TD-19(P) from the Chairman of SG 15 provides guidelines for new questions, and notes the need for SG 15 to participate in the following trends: GII, Multimedia, Open Networks, Photonic Networks, Integrated Transport Sys- tems (e.g., ADSL). It also includes copies of two draft new Questions from SG 9 Asymmetrical Networks for Television Distribution Services, such as Video on Demand and Physical Distribution of Multichannel Multipoint Distribution System (MMDS or microwave wireless distribution) Services. Mostafa Hashem Sherif, AT&T

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SG 15 WP 1 AND WP 2 MEETING ROSTER, NOVEMBER 14 – 22, 1995 P.A. Probst, Switzerland Chair SG 15 M. Yamashita, Japan Acting Chair WP 1/15 G.K. Helder, USA Acting Chair WP 2/15 INTELSAT M. Jones L. Bialik TSB F. Bigi E. Doron Argentina A. Satt Telefónica de Arg. E.C. Schieppati A. Segev Telefónica de Arg. A.M. Szpaizer I. Shapira Australia R. Ayre Italy S. Morello S. Brewer Alcatel Italia M. Fratti Canada L. Amar CSELT R. Drogo de Iacovo P. Wery CSELT R. Montagna Bell - Northern Res. K. Ahmad CSELT P. Usai Bell - Northern Res. D. Ho Ericsson Fatme M. Petrucci Bell - Northern Res. R. Rabipour Japan T. Kodate Mitel A. Tulai T. Nakazawa Téléglobe Canada S. Sharma Fujitsu N. Ohuchi China Ping Wei Le Fujitsu K. Sakai Mao Qian Graphic Com. Labs. S. Okubo Yi Chang Sheng Hitachi T. Kazawa Yao Ren Shun Japan Telecom Y. Yamazaki He Yida KDD H. Nakajima Chen Yun-Zhi KDD M. Wada Hao Zhian Mitsubishi Electric Y. Naito Denmark NEC M. Serizawa Tele Danmark E. Nielsen NEC M. Shinta Tele Danmark H. Nielson NEC T. Tajima Finland O. Aalto NTT S. Chikara Helsinki Telephone S. Törmälä NTT S. Hayashi Martis C. Balogh NTT H. Kotera Martis M. Givens NTT Y. Sato France J.P. Blin NTT T. Uchida P. Combescure NTT M. Yamashita G. Joncour NTT Mobile Com. T. Kawahara Alcatel CIT C. Stenstrom NTT Mobile Com. N. Naka France Telecom G. Dupin Oki Electric K. Ikeda France Telecom F. Lacordaire Oki Electric A. Shimbo France Telecom C. Lamblin Korea France Telecom Y. Loussouran Korea Telecom Jin-Hee Kim France Telecom I. Rajaomanana Samsung Elec. In Suk Chun France Telecom J. Thiennot Samsung Elec. Kook Kim Hong IBM Europe C. Gallian Netherlands MATRA Télécom. P. Lockwood Royal PTT Nederland K. Rijkse Germany M. Beierer Norway J. Kiil H.L. Koffler B. Nordset G. Schröder TELENOR O. Hansen I. Sebestyen TELENOR J.E. Knudsen G. Zelder TELENOR B. Nordset DeutscheTelekom H.W. Gierlich TELENOR H. Sandgrind DeutscheTelekom H. Kullman Portugal V. Ramos Deutsche Telekom J. Ott Russia V. Biryukov Deutsche Telekom W. Perske V. Minkin Deutsche Telekom G. Reim T. Petrenko DeutscheTelekom A. Schimm Singapore Siemens M. Terschluse Singapore Telecom K. Kuan Choon Shiong Wandel & Goltermann W. Miller Spain Great Britain D. Fisher Telefónica de España A.L. Lozano J. Gibbs Sweden A. Nunn L.M. Ericsson E. Ekudden AT & T Network UK J. Magill L.M. Ericsson A. Eriksson BT D. Alley L.M. Ericsson A. Höglund BT P. Barrett L.M. Ericsson S. Karlsson BT N. Kenyon L.M. Ericsson A. Lindsham BT M. Nilsson TELIA J. Alexandersson BT R. Reeves TELIA E. Bryntse Coherent Com. Sys. C. Reese TELIA Th. Nöjd Coherent Com. Sys. J. Skene Switzerland P.A. Probst Tektronix UK Ltd. M. Lum Siemens - Albis W. Boehl Greece Th. Papaioannou Swiss Telecom PTT M. Pralong Hungary Swiss Telecom PTT P. Vörös Hungarian Telecom. L. Barna Syrian Arab Republic N. Kisrawi Iran M. Beheshti-Pour Ukraine N. Birukov M. Hosseinzadeh V. Katok Israel A. Amir B. Korop Y. Beery S. Nesvitskaja S. Benjamin V. Yefremov

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USA G. Fereno Compression Labs D. Klenke D. Lindbergh COMSAT Corporation S. Campos Neto M. Neibert Creative Labs C. Gates J. Ng DataBeam C.J. Starkey G. Rekstad DSC Communications S. Bootman A. Schiano General DataComm M. McLoughlin R. Shaporst IBM S. Ardalan Analog Devices V. Bulayewsky Intel V. Kumar AT & T J. Anderson MCI Telecom. R. Born AT & T P. Bins MCI Telecom. H. Schoon AT & T K. Blette Motorola V. Eyuboglu AT & T M. Buckley PictureTel A. Crossman AT & T R. Cox PictureTel G. Helder AT & T G. Freundlich PictureTel R. Webber AT & T P. Kroon Rockwell Telecom. T. Geary AT & T M. Perkins Rockwell Telecom. J. Johnston AT & T C. Posthuma Rockwell Telecom. H. Su AT & T M. Sherif Sprint International M. Sucharczuk AT & T D. Skran Texas Instruments F. Whittington AT & T D. Sparrell US West Adv. Tech. J. Dahl AT & T Y. Tao Videoserver C. Grandgent AT & T K. Tewani VideoTelecom D. Hein

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December 1995 Vol. 6.8 Copyright © CSR 1995 51 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS REPORT OF ETSI TERMINAL EQUIPMENT (TE) PLENARY MEETING NOVEMBER 27 – DECEMBER 1, 1995, ANTWERP, BELGIUM TD 6 lists the ongoing actions and actions whose status has changed since the Nuremberg TE plenary (December 1994); TD 7 gives the same for the June 1995 plenary. TD 21 discharges actions resulting from the June 1995 TE plenary. The Chair’s report is separated into two documents, TE(95)133 Rev.1 and TD 5, which gives the latest update. The Chair attended 18 meetings since the last TE Plenary. MULTIMEDIA MANAGEMENT GROUP (MMG) In the absence of the Chair (due to illness), K. Sambor (Austrian PTT) chaired the meeting. TE(95)155 reports on the last meeting of MMG held in Athens. TD 26 presents a mark-up of parts of DTR/TE 10012, “TE Multimedia Standardization Areas to be Covered,” issued by K. Sambor. TD 27 presents comments on the same documents presented by PT74 from TE2. TD 36 and TD 37 from K. Sambor presents comments on the same document. The TE Chair indicated that, in view of the MMG Chair absence, those comments will be passed on to him for changes to be made to his referenced document and can be discussed at the next MMG meeting. TD 39 gives the latest version of DTR/TE 10012 prior to the TE Plenary. (It does not incorporate the comments made above.) An ad-hoc group on Milestone 3 Report on MMG planned to meet after the completion of the TE plenary. TD 46 is the proposed content of the report. It picks up the previously mentioned documents and more comments issued by the TE4 former Chair. A cleaned up version of this report on standardization will be available in February 1996. EUROPEAN MULTIMEDIA PROJECTS

A. Scrase (ETSI Secretariat) presented his notes on a meeting held in Brussels at the invitation of the CEC where a number of MM Pilot Projects in Europe were presented. While the participants did present the set up and the goals of those large scale experiments, none of them wished to present either conclusions or financial implications. Some of the technologies used for those MM projects appeared tuned to a small number of users but do not appear to be fitted to large scale Video on Demand (for example, FM bandwidth allocation). SRC6 IMPLEMENTATION STARTER GROUP Strategic Review Committee 6 (SRC6) was in charge of defining a set of coordinated actions and timing in the field of standardization while ETSI was to ensure proper availability of the European Information Infrastructure in due time. TE(95)120 is the list of recommendations put out by the SRC6. TE(95)197 gives the TE Chair evaluation of SRC6 conclusion impacts on TE work. TD 15 gives the content of a report to the ETSI TA (Technical Assembly) on the EPIISG (European Project on Information Infrastructure Starter Group) progress. EPIISG has been created as a result of SRC6 Recommendations. A number of liaisons have also been established between EPIISG and Standardization bodies and fora. A road map for EII (European Information Infrastructure) standardization was being prepared for the end of December. TE1, TELEMATIC AND RETRIEVAL SERVICES A list of documents for approval by TE was first discussed. The list was as follows: • API (Application Programming Interface) for the manipulation of multimedia and hypermedia information objects. This document, created by ETSI TE1 (which was congratulated by ISO for its good job) was also picked up by an ISO CD ballot. This raised the question of duplication of effort in Standards and at the NSOs (National Standards Organizations). The TE Chair insisted that this document be circulated for PE under ETSI rules and that ISO should be informed by letter of this situation. • Representations of scripts for AVI (Interactive Audiovisual Services) applications was approved to go to PE. • VEMMI (Videotex Enhanced Man Machine Interface) extensions were approved to go to UAP (Unified Accelerated Procedure). It was based upon ITU-T Recommendation T.107 which had been voted under the Reso- lution 1 mechanism in March 1995. Once this document is approved, the old document, ETS 300282, should be deleted by the proper action toward the NSOs. • Extensions of Videotex data syntax for alpha mosaic display was approved to go to UAP. • Priority setting and description of interactive audio-retrieval services on narrowband networks will be published as an ETR and was approved by TE to go to publication (no need to go to PE).

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A number of new work items were proposed to TE, and most of them were approved with some editorial changes. TE1 established a liaison with DAVIC and obtained agreement to work on the following: • End-to-end protocols for multimedia information retrieval services: coding of multimedia and hypermedia information for basic multimedia applications (MHEG-5) not done by DAVIC. TE1 has the expertise since MHEG-5 is a subset of MHEG-1 for which TE1 already did the coding in the past. • End-to-end protocols for multimedia information retrieval services: use of DSMCC for basic multimedia information based on the ISO CD document. • End-to-end protocols for multimedia information retrieval services: API for MHEG-5. While DAVIC has already published a set of specs, it was not the intent of ETSI TE1 to duplicate work but to fill the gaps in the DAVIC specs and to contribute to standards where it is known that DAVIC will not do it. • End-to-end protocols for multimedia information retrieval services: VEMMI enhancements to support broad band multimedia information retrieval services. • End-to-end protocols for multimedia information retrieval services: application walk-through of a DAVIC system. (This will not become an ETS but an ETR.) • End-to-end protocols for multimedia information retrieval services: Interworking between DAVIC-compliant broadband systems and videotex systems. (ETR will be the deliverable.) As a result of the approval of the document on priority setting by TE (see above), three new work items were proposed. Only one received enough member support and that was Access to interactive audio-visual retrieval services without data facility: access for ISDN or PSTN video telephony terminals to audio-visual data bases using DTMF. Four project teams report into TE1. PT73V was working on the API for File Transfer, both through FTAM (File Transfer, Access and Management) and Euro-file transfers. PT75 will do most of the work on the new work items listed above on multimedia information retrieval services. PT53 and PT63 had basically completed their jobs. TE2, TELEMATIC TERMINALS

WG 1 FACSIMILE GROUP 3 AND GROUP 4

A revised version of ETS 300242 (G3 facsimile equipment) was approved to go to Public Inquiry. An animated discussion followed to decide what additional activity should be carried on in the fax group 3. Some members supported continuing work to establish European requirements and conformance tests to ETS for facsimile. Other members supported the ITU-T as the leader in this field; it should be possible to attach an ETSI style sheet to a T.30 Recommendation to make it an ETS. The TE Chair decided to delete the work item and let TE2 members come back with proposals if they feel that further work is needed. WG 2 ODA (OPEN DOCUMENT ARCHITECTURE)

prETS 300498-1, Open Document Architecture Communication Services Part 1 Basic Services, TE(179), was approved to go to PE. TD 32 proposes a split of ODA activities by establishing two work items, one on simple ODA systems and one on more complex systems and conformance testing. A strong contribution was presented by Telefonica of Spain concerning the future work on ODA, TD 23. Except for K. Sambor (Austrian PTT), who strongly defended the continuation of work on ODA, the members of the meeting agreed with the Chair to stop any further work on ODA in ETSI, to remove any reference to ODA in the TE2 terms of reference, and to properly terminate the work which has been started. This decision was made considering the lack of participation of members to ODA WG 2, considering the existence of de facto standards such as those brought by Microsoft for Document Architecture, and considering the ongoing work in other standard bodies. The results of PT76 will be published as an ETR (European Technical Report). The revised work sheet on ODA, as a result of those discussions, is given in TD 45. ETS 300025 Rev.1, PCI for ISDN, has two cases: Case A based upon the former PCI for ISDN and Case B based upon CAPI (Common Application Programming Interface). Case A did not support the Microsoft Windows 95 capability. This document was amended so that the edition that will go to PE defines that capability in both cases. Conformance testing to the above mentioned ETS will need to be established, and a call for experts will be made at the end of the PE period (May 1996).

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The ETR on General Architecture for PCI (down graded from an ETS) was running late and will be approved by correspondence. pr ETS 300243-1, Edition 2, Programmable Communication Interface APPLI/COM for facsimile Group 3, facsimile Group 4, teletex, and services conformance testing, was running into some difficulties due to the fact that its description, done in TTCN (tree and tabular combined notation), had not been validated and at the same time, was not in machine readable format. Therefore, it could not go through a compiler. The PEX (Help Desk for Conformance from ETSI Secretariat) is evaluating the work load to convert the existing TTCN description into a machine readable form. It was decided not to proceed with publication of the document until the matter is resolved, to ensure good quality of ETSI deliverables. A TCR-TR (Technical Committee Report-Technical Report) was being prepared to identify the needs for extension of the existing PCIs to a Generic PCI for Multimedia Application. This work item was running late. A resolution meeting was planned for December 1, 1995. The work on a PCI for GSM is well under way. This work was done in SMG4 (Special Mobile Group 4) and was reviewed by TE2 STC due to its expertise on PCIs. Two approaches were taken by SMG4: one PCI was based upon an extension of the AT Command Set, the other was based upon ETS 300325-1. The assumption was that no change would be made to ETS 300325-1. TE2 also volunteered to establish the conformance testing of the new GSM PCI. TE2 initialized liaisons to XTI, X-Open Transport Interface, and evaluated how XTI documents could become ETSI documents. TE3, MESSAGE HANDLING SYSTEM TD 12 contains the results of a CEN (Commission Europeenne de Normalisation) Project Team on the subject of User Requirements for Character Set Technology. The Chair reported that Internet sometimes operates with 7 bits and that most National Alphabets in Europe require 8 bits and some require 16 bits. Proposals to use a 16 bit alphabet on 7 or 8 bit networks had been made but lead to rather complex algorithms. TD 22 is a letter from the ETSI Director to all ETSI Chairs indicating the existence of the report on character set and asking those Chairs to comment. TE will have to approve TD 12 on behalf of the whole ETSI. The work sheets for TE3 are contained in TE(95)131 whenever not superseded by TE(95)170. A new work sheet will need to be generated to cover Strategy for Messaging Management in view of recent US contributions to ITU proposing to base that management on Recommendations for MHS (X.400 Message Handling System) Management. Interworking between Internet and MHS is also a subject that will require the attention of TE3 members in the very near future. TE4, AUDIOVISUAL AND VOICE TERMINALS The TE4 Chair-elect, E. Fitzgerald (Consultant for Motorola), presented the TE4 report (TD 44). TD 14 is a proposed procedure regarding prETS 300483, “TE ISDN Multipoint Communications for Audio Visual Services, Main Functionalities and Basic Requirements for Multipoint Control Unit (MCUs).” Having received no comments during the PE, it was approved unchanged by TE to go to National Voting. A number of documents were not received by TE in time to be approved. They will be approved by correspondence. They are: • ETS 300481 - ISDN B-Channel Aggregation Procedures and Terminal Requirements (Vote) • I-ETS 300302-1 - ISDN Video Telephony Teleservices Part 1: Electro-acoustic characteristics for 3.1 kHz bandwidth handset terminals (UAP) • TBR8/prA1 - ISDN Telephony 3.1 kHz Teleservice Attachment Requirements for Handset Terminals (See also below.) (UAP) • I-ETS Video Telephone Reference Terminal - Data Communication Using In-Band Signaling Principles (PE) • I-ETS ISDN Audiovisual Services In-Band Signaling Testing Part 1: Test Suite and Test Purposes (PE) • I-ETS ISDN Audiovisual Services In-Band Signaling Testing Part 2: Abstract Test Suite and Partial PIXIT Proforma (PE) • I-ETS ISDN Audiovisual Services In-Band Signaling Testing Part 3: PICS Proforma Specifications (PE)

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The work on revision of TBR8 will start as soon as the TBR3 amendments have been completed. The Commission asked for an improvement in the schedules for publication of revised TBR8 (handset telephony requirements over ISDN). The start of work on TBR38 on analog voice requirements (in conjunction with TBR37, voice access to PSTN) led to the approval of a new work item and to an active discussion. The terminal directive speaks of requirements in the 4g justified case. The debate centers on what is live voice. Some delegates felt that TBR was not needed; others felt that the scope of the TBR needed to be very well defined by ACTE and the Commission; the CEC represen- tative stated that what was really meant by live voice was the plain old telephone and the telephony service. The Commission depends on ETSI to identify the essential requirements. The Commission also needs the document by mid-1997 at the latest. If ETSI cannot deliver, the Commission will use other means of getting those requirements expressed. The technical report, “Video telephone reference terminal,” keeps getting delayed. The Editor was having difficulties gathering the proper information. The TE Chair asked the TE4 Chair to either publish the document as is or to cancel the work item. This will be discussed at the next TE4 meeting. TE4 is becoming the center of expertise within ETSI for speech encoding, decoding, and transcoding. This is a result of the disbanding of TM5 and good working relations established with SMG. Two new work items were approved in addition to the one mentioned above for TBR38: • A new work item to update the VTQME report (Voice Transmission Quality Measurement on a network). This work had been very well received by ITU-T and had also received quite a bit of interest from the US. It is a result from picking up the work of TM5. • A miscellaneous work item on transmission delays to contribute to the new TM3 work item. The next regular meeting of TE4 will be in Sophia Antipolis, France, April 15-19, 1996. TE5, TERMINAL ACCESS TO PUBLIC NETWORKS TE5 Chair D. Maxey’s report is contained in TD 33. The following documents were approved to go forward to National Voting: • ETS 300002 Ed 2: PSTN; Category II specification for 9600 or 4800 bits per second duplex modems standardized for use on the PSTN. (V.32) • ETS 300114 Ed 2: PSTN; Category I and common Category II specification for modems standardized for use on the PSTN. • ETS 300116 Ed 2: PSTN; Category II specification for 1200 bits per second duplex modems standardized for use on the PSTN. (V.22) • ETS 300117 Ed 2: PSTN; Category II specification for 2400 bits per second duplex modems standardized for use on the PSTN. (V.22bis) • ETS 300118 Ed 2: PSTN; Category II specification for 1200 bits per second half duplex and 1200/75 bits per second asymmetrical duplex modems standardized for use on the PSTN. (V.23) • ETS 300492 Ed 1: PSTN; Category II specification for 14400, 12000, 9600, 7200 and 4800 bits per second duplex modems standardized for use on the PSTN. (V.32bis) (new) TBR2, Access to packet switched networks, was going to National Voting. It contains only physical layers requirement. There was a question regarding what to do with layer 2 and layer 3 former TBR2 requirements. The TCR-TR on results of monitoring frame relay activities in Europe was approved with the editorial changes contained in TD 35 (Motorola). The following new work items were approved by TE with some discussions: • Amendment to TBR3 Edition 1 at the request of ACTE (Approvals Committee for Terminal Equipment) which did not approve TBR3 as is (ISDN Basic Rate Access). The same will be done for TBR4 with BTC (Business Telecommunications Committee) involvement. • Revision of Edition 1 of ETS 300115 for V.21 modems. • Work to start on voice access TBR. TBR is to be split into two parts: the network access part will be handled by TE5 in the new work item; the voice quality part will be handled by TE4. This will result in two TBRs: TBR37 and TBR38.

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• Work to start on ISDN access to packet services for basic access and primary rate access. Some discussions took place. This work item was initially assigned to SPS5 and will be requested to be transferred back to TE5 where it belongs. The European networks have not harmonized their ways of handling packets, and it will be up to the terminal to adapt to those different situations (Channel B, Channel D). Some terminal manufacturers feel that TBR3 and 4 are sufficient. • As soon as ACTE indicates so, TE5 will drop its work item on Edition 2 of TBR3. Two resolution meetings were planned to sort out the 200 pages of comments received by the Editor of TBR21 (non- voice access to PSTN). The work on use of terminal in series/parallel is closely linked to the work on TBR21 and the deliverable item, which will be an ETR, is highly dependent on the content of TBR21. ETR on Common Interpretation of Essential Requirements in PSTN access had not reached consensus at the last TE5 meeting. There was still a lot of confusion between the live voice essential requirements and the non-live voice requirements. Work on broadband access for terminals is starting, and a draft I-ETS should become available soon. TE5 decided not to work on a multimedia transport protocol proposed by Siemens and Austrian PTT at the last TE plenary. The authors of that proposition were invited to present it to other multimedia-related groups, possibly NA. TD 30 contains the result of an action arising on B-ISDN at the June meeting. It concludes that the Siemens/PTT Austria contribution was considered to be a proposal for a new work item for multimedia. Since this is not covered by the mandate of the TE5 B-ISDN group, it was suggested that the contribution be allocated to a multimedia-related group. TE5 continues to monitor EMC (Electromagnetic Compatibility), safety, and protection works on behalf of TE and to monitor activities on advice of charging on PSTN. TE5 is involved in CLI, and an interim report was sent to the Commission on the matter of PSTN harmonized plug and socket connector. The next meeting of TE5 will be in Sophia Antipolis, France, March 4-8, 1996. TE6, DIRECTORY SYSTEMS The TE6 Chair presented his STC activities which are held jointly with EWOS. The goal of TE6 is to keep ETSI members informed about the activities taking place in the Standard arena in the field of X.500 Directories and to check that work is progressing on those items. TE6 will generate a TE permanent document that will not have a TCR-TR status but will contain all the information about Directory Taxonomy. TE(95)117 contains the TE6 report. TE(95)156 and 157 updates the work item sheets. The question within ETSI is how to handle those documents that are already approved by EWOS and processed by SGFS (Special Group for Functional Standards). The TE6 Chair will prepare an extract of those documents and will attach a multiple voting form to them. Any TE member wishing to get the full document should request it from V-A Hoang (FT), Chair of TE6. The TE6 Chair announced that his company does not wish him to continue as Chair. As a result, the future of TE6 is uncertain. TE9, CARD TERMINALS G. Raimann (Landis & Gyr - FEEI), TE9 Chair, presented his report. His STC is very dynamic, so dynamic that he proposed documents for publications of a work item which has not yet been accepted. A work item, “Additional Telecom Features of IC (Integrated Circuit) card,” will be approved at next TE9 meeting. A work item dealing with “synchronous cards” was modified to address the interoperability of synchronous pre-paid cards with terminal systems. A new work item, “Definition of identification of chip card for ETSI applications” (such as GSM, Tetra cards), was approved. A work item on handling of other standards was classified in the miscellaneous MI work item. Two work items consisting of defining the conformance testing of smart cards on the card side and on the terminal side were accepted. Those work items include the work of PT BUV which will start early 1996. The revised work items that will be sent to TE for approval are contained in TD 48. A coordination committee of card experts was started within ETSI at the request of PAC (Program Advisory Committee) and will try to harmonize the work going on in TE, SMG (Special Mobile Group), and DECT (Digital European Cordless Telephone).

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CEC RELATED MATTERS TE(95)127 gives the new mandates assigned by the Commission to ETSI. Those mandates that relate to TE work are detailed in TE(95)195, and they deal with the following items: • 64 kbit/s leased line provided through an aggregation of nx64. There will be no new TBRs generated on this mandate. The existing 64 kbit/s G.703 leased line will suffice. A work item will be assigned to TE5. • Calling Line Identification through PSTN and interworking with CLI carried by ISDN. Mandate to standardize. This may result in some slight modifications of the existing PSTN elements. • Analog voice terminal TBRs (network access and voice access). (See TE4 nad TE5 reports above.) • General access to networks through ISDN basic and primary rate. (See TE5 report above.) • Transport IC cards for road toll connection. Some relation to TE9 work. • Develop standards on B-ISDN, ATM, WAN networks that will constitute the Trans European Network Backbone. Establish periodic progress reports of the work and ensure market acceptance of that progress. • Develop standards on frame relay. (TE5 concluded that no new frame relay standards were needed.) • Develop sound, picture information coding. It is such a wide scope mandate that it requires better definition. • Define Software Interfaces to I.C.T.(Information Technology, Consumer Electronics and Telecommunications) services (API/PCI). The mandates for standards that directly affect access within the network such as HDSL/ADSL (High-rate Digital Subscriber Loop/Asymmetric Digital Subscriber Loop) are assigned primarily to the TM (Transmission and Multiplexing) Committee. STANDARDS MANAGEMENT

PT (PROJECT TEAM) MANAGEMENT

TD 29 is the status of the different project teams. There was no new project team asked for or allocated to TE. The EC (European Commission) has revised its way of funding PTs. PTs leading to a mandatory or regulatory standard will be funded 100% by the Commission; others will be funded with a maximum of 50% of the PT cost, the remaining part being funded by ETSI. The following PTs are under TE responsibility for 1996: • Conformance Testing ISDN Low Layers (26V) • Audio Text (36V) • Conformance Testing ISDN PCI (43V) • File Transfer ISDN (44V) • Test ISDN Video Phone (57V) • Test File Transfer over ISDN (59V) • API for File Transfer ISDN (73V) • Testing Intelligent Cards (BUV) • ODA Profiles part 2 • Revision ETS 300080 (51) • ODA Service Profiles (61) • Multimedia (63) • PCI for Multimedia (74) • Multimedia End-to-End Protocols (75) GENERAL

ETSI has decided to put in place a procedure to convert a PAS (Publicly Available Specification) into ETSI documents. Those PASs are produced by entities outside of ETSI (such as Fora). Experience will show how this procedure works. There has not yet been any voluntary request from those entities to proceed with that activity. PASs should not conflict with ongoing standards in ETSI. PASs should normally result in (I)-ETSs (Interim European Telecommunications Standards). The term Technical Specifications does not exist in ETSI jargon and will need to be changed. The ETSI Secretariat’s goal is to make ETSI documents more readily available to its members. For example, a GSM CD-ROM will become available prior to the end of this year. This implies conversion of all ETSI documents into a single text processing format: Word for Windows 6.0. This format will itself be converted into PDF (Portable Document Format), similar to Post Script, in that the document sent to the requester is monolithic and cannot be changed or edited easily.

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LIAISONS

LIAISON WITH EWOS

J. Pointer (BT), Vice Chair of ETSI TE, represented the TE Chair at EWOS (European Workshop on Open Systems) TA (Technical Assembly) and was part of the EWOS Evaluation team. EWOS was undergoing a detailed audit of its operations, and its future was not totally ensured. The report of EWOS TA 30 is contained in TE(95)176. EWOS was considering evolution from standards making to procurement guidance to help customers make the right choices. This is similar to producing an EPHOS (European Procurement Handbook for Open Systems) guide. EWOS was also considering how to go along with the conclusions of SRC6 (Strategic Review Committee 6) on European Information Infrastructure. Dr. W. Black, Director of EWOS, commented that some EGs (Expert Groups) of EWOS may disappear rather rapidly now that X-Open has become a member of EWOS. EWOS agreed to place on the Internet Web the GOSS (Guide to Open System Specifications). LIAISON WITH SPS (SIGNALING PROTOCOLS AND SWITCHING)

The confusion continued on the topic of assigning HLCs (Higher Layer Compatibilities) for ISDN file transfers using either FTAM or Eurofile transfers. It was understood that Euro-file transfer was to get a European HLC while FTAM would get an ITU-T HLC. SPS5 liaison proposed to assign a European HLC for FTAM file transfer (TE(95)135). LIAISON WITH NA NETWORK ASPECTS

TD 13 is a liaison statement from STC NA1 proposing to send the service description for both FTAM and Eurofile transfers to ITU-T and asking ITU-T to assign two HLCs for each file transfer service. ETSI ONP (OPEN NETWORK POLICY) 14

This meeting was attended by J. Pointer (BT), and was, in fact, of a wider scope than ONP. It checked the status of the different mandates assigned by the Commission to ETSI. The following items were discussed as reported in TE(95)174: • CEC (European Committee for Standardization) invited ETSI to be represented at a hearing on “Universal Service in a Competitive Environment.” • Voice telephony directive completed its first reading. The final text will be approved by the end of 1995, and member countries have 12 months to implement it. • With respect to adaptation of the leased line directive, CEC will issue a new mandatory package for leased lines. • Access to the local loop mandate - The owner of the local loop is not necessarily the owner of the local switch according to the commission. Some clarification will be brought in a second work order to be issued. • ISDN Primary Rate Access Connectors - One manufacturer had been found to manufacture such a connector based on ISO 10073. Some interim measures need to be provided so that another manufacturer can be identified. • A new CLI (Calling Line Identification) mandate from the commission had been decided. It will be assigned to STC TE5. • CEC was still waiting for a status report on harmonized plug and socket for PSTN. An interim report will be produced by TE5 on this matter. LIAISON WITH PAC

PAC has been giving priorities on standard activities and advising the ETSI TA accordingly. TE(95)187 contains the 1995 PAC annual report. PAC advised the creation of the CEG, Integrated Circuit Card Expert Group. TE(95)188 is a report of that first experts group meeting. It is not yet clear from the TE9 Chair, G. Raimann, how CEG will work in relation with the existing ETSI structures: Can it create its own work item? Which parent committee does it report to? Can it generate its own standards? The TE Chair replied that CEG can create its own work item, that it should report to SMG, and that it cannot publish its own standards without the approval of its parent committee and the experts of related groups. TE(95)190 gives the list of work items related to IC Cards. It appeared that Europe had a lead position in that area. PAC developed a systematic approach to ETSI Standards work using a key word approach. Key word #1 gives the main technological platform subject to standardization. Key word #2 represents the different expertise available in ETSI TCs. TE(95)189 lists key words and the matrix of ETSI work items. Examples of key word #1 type include cordless, B-ISDN, and MHS/Directory. Examples of key word #2 type include architecture, conformance testing, in-

58 Vol. 6.8 Copyright © CSR 1995 December 1995 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS terface/protocols, and management aspects. The PAC then classified all work items of ETSI Data Base in a matrix. Out of 4834 work items, only 214 were not allocated using the proposed key word lists. It was strongly recommended by PAC to systematically refer to those key words in work items. OTHER HIGHLIGHTS Terms of reference of TE were modified to reflect the TE4 new responsibility in speech coding. TM terms of reference were also modified in that respect. A number of carry over items from previous discussions were presented. TD 50 lists the documents approved at this TE Plenary. TD 51 is the modified work sheet for TBR8 alignment with TBR3. TD 47 is a proposed answer from H. Layec, Chair of TE1, to TD 12 (CEN/TC304/PT01), the project team report. This document led to a laborious discussion on the relative percentages of Videotex and Internet/PC/modem per European countries. TE1 rejected TD 12, but TE was still asked to consolidate the replies of the different ETSI Committees to TD 12. Jacques Besseyre, AT&T France

ETSI TE PLENARY MEETING ROSTER, NOVEMBER 27 – DECEMBER 1, 1995, ANTWERP, BELGIUM G. Lawrence, GPT Ltd., UK Chairman of ETSI TE Committee Austria KPN PTT Telekom BV Jan Dietz Landis & Gyr - FEEI Gerhard Raimann Norway Austrian PTT Klaus Sambor Comlab Norwegian Telecom Jarl Fjerdingby Belgium Norwegian Telecom. Auth. Rasmus Trevland EWOS W. Black Telenor A.S. Trond Ulseth European Com. DG XIII / A2 Brian Jenkinson Russia Alcatel Bell Willy Noppe Ministry of P & T Serguei Rakhmanov Denmark ZNIIS - Central Sc. Res. Alexey Vasilyev Tele Danmark Allan Buchanan Inst. of Telecom. National Telecom Agency Helmer Petersen Spain Finland Dir. Gen’l de Telecom. Enrique Berrojalviz Telecom. Admin. Centre Antero Saarinen Palacio Comunicaciones France Telefónica Pablo Calvo A T & T Jacques Besseyre Sweden Alcatel Business Systems Christine Cordonnier Ericsson Bus. Networks AB Per Döfnäs France Telecom Jean-Michael Garnier Telia AB Mikael Forsström France Telecom Van-Anh Hoang Switzerland France Telecom Hervé Latec OFCOM Fed. Office for Com. Jacques Bovay PMC Dept ETSI Sec. Adrian Scrase Swiss Telecom PTT Hansueli Gerber Germany Swiss Telecom PTT Markus Kämpfer Deutsche Telekom AG Frank Jürgens United Kingdom Professor Schnurr Deutsche Telekom AG Werner Simon British Telecom Reg. Svcs David Maxey Siemens AG Manfred Mall British Telecom Reg. Svcs Joseph Pointer Hungary GPT Ltd G. Lawrence HTC Telecom Hungary Gábor Nagygyorgy GPT Ltd G. Lovett Italy Motorola LTD Edward Fitzgerald Italian PT Ministry Alberto Giuseppini NEC Tec. Ltd Mark James STET Italtel Stefano Mariani Telecom. Tech. Div. Italtel SIT Alfonso Reda Racal - Datacom Ltd John Long Netherlands

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1996 Meeting Schedules Continued From Back Cover Subject to Change without Notice T1P1 Jul 8 - 12 --- TR-30 Oct 14 - 18 --- TR-45.2 Jul 8 - 12 Quebec City, PQ TR-45.3 Oct 14 - 18 Austin, TX TR-45.3 Jul 8 - 12 Quebec City, PQ TR-45.5 Oct 14 - 18 Eastsound, WA TR-45.5 Jul 15 - 19 Burlington, VT ITU-R TG 8/1 Oct 15 - 25 Geneva T1E1 Jul 22 - 26 --- ITU-R WP 8A Oct 29-Nov7 Geneva TR-45.4 Jul 29-Aug 2 Walnut Creek, CA T1E1 Nov 11 - 15 --- TR-29 Aug 5 - 8 Sonoma, CA TR-29 Nov 4 - 7 --- TR-30 Aug 5 - 9 --- TR-45.2 Nov 11 - 15 CO Springs, CO TR-45.2 Aug 5 - 9 Calgary, Alberta TR-45.5 Nov 11 - 15 Newport Beach, CA TR-45.3 Aug 12 - 16 --- T1A1 Nov 18 - 22 --- TR-45.5 Aug 12 - 16 --- TR-45.4 Nov 18 - 22 El Paso, TX T1A1 Sep 9 - 13 --- TR-45.3 Nov 18 - 22 Dallas, TX TR-41 Sep 9 - 13 Ottawa, Ontario ETSI TE Nov 25 - 29 Dublin, Ireland TR-45.4 Sep 9 - 13 Montreal, Quebec TR-30 Dec 2 - 6 San Antonio, TX TR-45.5 Sep 9 - 13 Williamsburg, VA TR-41 Dec 9 - 13 --- T1S1 Sep 16 - 20 Monmouth, NJ TR-45.2 Dec 9 - 13 St. Pete’s Bch, FL TR-45.2 Sep 16 - 20 Seattle or Chicago TR-45.4 Dec 9 - 13 St. Pete’s Bch, FL TR-45.3 Sep 16 - 20 Seattle, WA TR-45.5 Dec 9 - 13 Kihei, HI T1P1 Oct 7 - 11 --- TR-45.3 Dec 16 - 20 Cancun, Mexico TR-45.2 Oct 7 - 11 Burlington, VT TR-45.4 Oct 7 - 11 Oakbrook, IL

The next issue of Communications Standards Review – Telecommunications (Vol. 7 #1) is scheduled for January–February 1996.

Communications Standards Review regularly covers the following committee meetings:

CSR-R CSR-T TIA TR-41.6 TIA TR-29 TR-45 TR-30 TR-46 TR-41 ITU-R: SG 8A ITU T: SG 8 SG 14 SG 15 / 1 and 15 / 2 ETSI: TE Plenary

60 Vol. 6.8 Copyright © CSR 1995 December 1995 COMMUNICATIONS STANDARDS REVIEW – TELECOMMUNICATIONS

ACRONYM GLOSSARY

AAL ATM Adaptive Layer ACTE Approvals Committee for Terminal Equipment ADSL Asymmetric Digital Subscriber Loop (Line) ARQ Automatic Repeat Request ATM Asynchronous Transfer Mode B-ISDN Broadband ISDN BAS Bit-rate Allocation Signal CBR Constant Bit Rate CCR Comparison Category Rating CD Committee Draft CEC European Committee for Standardization CLI Calling Line Identification CME Circuit Multiplication Equipment CNG Comfort Noise Generator CIF Common Intermediate Format CSS Composite Source Signal DCE Digital Cellular Equipment DCME Digital Circuit Multiplication Equipment DECT Digital European Cordless Telephone DoD Department of Defense (U.S.) DSM-CC Digital Storage Media - Command and Control DSP Digital Signal Processing DSVD Digital SVD DTE Data Terminal Equipment DTMF Dual Tone Multi Frequency EREC Error Resiliant Entropy Code/Error Robust Entropy Code ETR European Technical Report EWOS Europena Workshop on Open Systems FCC Federal Communications Commission (U.S.) FDM Frequency Division Multiplexing FEC Forward Error Corrector FPLMTS Future Public Land Mobile Telephone Systems FTAM File Transfer, Access and Management GSM Global System for Mobile Communications (formerly Groupe Speciale Mobile) GSTN General Switched Telephone Network (e.g., PSTN) HDLC High Level Data Link Control HLC Higher Layer Compatibility HRD Hypothetical Reference Decoder IRS Intermediate Reference System ISDN Integrated Services Digital Network LAN LAPM Link Access Protocol Modem (V.42) LBC Low Bit -rate Coder LDCELP Low Delay CELP MCU Multi-point Control Unit ME Mobile Equipment MFP Multi-Function Peripheral MFPI Multif-Function Peripheral Interface MHEG Multimedia and Hypermedia Experts Group MIPS Million Instructions Per Second MLC Multiple Logical Channel MLP Multi-Layer Protocol MMDS Multichannel Multipoint Distribution Service MMG Multimedia Management Group (ETSI) MOPS Million Operations Per Second MS Mode Select MSD Master Slave Determination MUX Multiplexer NA Network Aspects NATO North Atlantic Treaty Organization NISDN Narrowband ISDN ODA Open Document Architecture

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ONP Open Network Policy PB Personal Base PDU Protocol Data Unit PE Public Inquiry (ETSI) PSC Picture Start Code PSTN Public Switched Telephone Network QCIF Quarter CIF REVAL Procedure for Evaluation of Radio Technologies for FPLMTS ROM Read Only Memory SAVD Simultaneous or Alternating Voice Data SCF Supervisory and Control Function SDL Specification and Description Language SID Silence Insertion Descriptor SLER Signal to Listener Echo Ratio SMG Special Mobile Group SNR Signal to Noise Ratio SOVA Soft Output Viterbi Algorithm SQEG Speech Quality Expert Group SRC Strategic Review Committee (ETSI) SRTS Synchronous Residual Time Stamp STC Sub-Technical Committee (ETSI) STE Secure Terminal Equipment SVD Simultaneous Voice Data TBR Technical Basis for Regulation TCH Transparent Circuit Handling TCON Telenor Research’s error Concealment Decoder TCR-TR Technical Committee Report – Technical Report TDF Transportable Document Format TE Terminal Equipment (ETSI Committee) TMN Telecommunications Management Network TSB Telecommunications Standardization Board (ITU) TSB Telecommunication Systems Bulletin (TIA) UAP Unified Accelerated Procedure UEP Unequal Error Protection USB Universal Serial Bus UIH Unnumbered Information with Header check VAD Voice Activity Detector VM Verification Model WAN XOR Exclusive OR

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1996 MEETING SCHEDULES AS OF DECEMBER 21, 1995 Subject to Change without Notice V.34 Rapp Jan 8 - 10 Clearwater, FL SG 15 Rapp Mar 19 - 26 France TR-45.4 Jan 8 - 12 Walnut Creek, CA ITU-R TG 8/1 Apr 15 - 26 Germany TR-45.5 Jan 8 - 12 San Diego, CA T1P1 Apr 15 - 19 --- SG 15 LBC Jan 9 - 12 San Jose, CA TR-30 Apr 15 - 19 --- TR-45.2 Jan 11 Arlington, TX TR-45.2 Apr 15 - 19 Austin, TX T1P1 Jan 15 - 20 Pleasanton, CA TR-45.4 Apr 15 - 19 Austin, TX TR-29 Jan 15 - 18 San Antonio, TX TR-45.5 Apr 15 - 19 --- TR-45 Jan 15 - 18 Pleasanton, CA T1E1 Apr 22 - 26 RTP, NC TR-45.2 Jan 15 - 19 Orlando, FL TR-45.3 Apr 22 - 26 Atlanta, GA T1E1 Jan 22 - 26 Orange, CA SG 15 LBC Apr 23 - 26 Dallas, TX TR-45.3 Jan 22 - 26 Vancouver, BC TR-45.5 May 6 - 10 San Francisco, CA G.dsvd Rapp Jan 24 - 26 Costa Mesa, CA TR-29 May 13 - 16 Middletown, NJ TR-30 Feb 5 - 9 Honolulu, HI TR-45.2 May 13 - 17 Monterey, CA SG 8 Feb 6 - 15 Geneva TR-45.3 May 20 - 24 Calgary, Alb TR-45.2 Feb 12 - 16 New Orleans, LA TR-45.4 May 20 - 24 Chicago, IL TR-45.3 Feb 12 - 16 New Orleans, LA SG 15 May 28-Jun 7 Geneva TR-45.4 Feb 12 - 16 Dallas, TX TR-30 Jun 3 - 7 --- TR-45.5 Feb 12 - 16 Birmingham, AL TR-41 Jun 3 - 7 Rosemont, IL ITU GII TF Feb 17-19 Geneva ETSI TE Jun 10 - 14 Madrid, Spain SG 15 Rapp Feb 26 - 29 Rome, Italy TR-45.2 Jun 10 - 14 Vancouver or TR-41 Mar 4 - 8 Fort Meyers, FL Chicago TR-45.2 Mar 11 - 15 Santa Barbara, CA TR-45.5 Jun 10 - 14 Vancouver or TR-45.5 Mar 11 - 15 Santa Barbara, CA Chicago T1A1 Mar 18 - 22 Orlando, FL T1A1 Jun 17 - 21 --- TR-45.3 Mar 18 - 22 --- TR-45.3 Jun 17 - 21 Toronto, Ontario TR-45.4 Mar 18 - 22 Hilton Head, SC TR-45.4 Jun 24 - 28 Durango, CO SG 14 Mar 19 -27 Geneva 1996 Meeting Schedule Continued on page 60

Visit the CSR Web Page: http://www.csrstds.com The Web Pages include an updated Telecom Acronym Glossary, sample reports from CSR-T and CSR-R, data sheets on all CSR technical journals, updated meeting schedules (as above), and background material on telecom standards and CSR (the company).

Communications Standards Review –Telecommunications (ISSN 1081-4655) is published 6 - 8 times per year, within days after the latest, related standards meetings. Editor: Elaine J. Baskin, Ph.D. Technical Editor: Ken Krechmer. Copyright © 1995, Communications Standards Review. All rights reserved. Copying of individual articles for distribution within an organization is permitted. Subscriptions: $595.00 per year worldwide. Discounts for additional subscriptions are available. Submit articles for consideration to: Communications Standards Review, 757 Greer Road, Palo Alto, CA 94303-3024 U.S.A. Tel: +1-415-856-9018. Fax: +1-415-856-6591. Internet: [email protected]. CIS: 72540,113. WWW: http://www.csrstds.com. 16908

December 1995 Vol. 6.8 Copyright © CSR 1995 63