CSR Volume10 #8, August-B, 1999

COMMUNICATIONS STANDARDS REVIEW

Volume 10, Number 8 August-B 1999

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-41.3.4 Interim Meeting, June 21 – 23, 1999, Vancouver, BC...... 2 TR-41.3.4 Interim Meeting Roster, June 20 – 21, 1999, Vancouver, BC...... 5 SG15, Working Parties 1 and 2, June 21 – July 2, 1999, Geneva, Switzerland...... 6 SG15 WP1 and WP2 Recommendations approved by Resolution No. 2 Process...... 6 Other SG15 WP1 and WP2 Approvals...... 6 SG15 WP1 and 2 Recommendations Determined...... 6 WP1/15, Network Access...... 7 WP 2/15, Network Signal Processing...... 11 Question 1, WP1/15 - Access Network Transport...... 14 Question 2, W1/15 - Characteristics of optical systems in local access networks...... 14 Question 3, WP1/15 - DCEs for Digital Leased Circuits...... 15 Question 4, WP1/15 - Transceivers for Subscriber Access Systems...... 16 Question 5, WP2/15 - Management Aspects of Signal Processing Network Elements...... 26 Question 6, WP2/15 - Circuit Multiplication Equipment and Systems...... 27 Question 7, WP2/15 - Network Echo Control , Interaction of Echo Controllers & Network Eqpt...... 29 Question 8, WP2/15 - Speech, Voice-Band Data & Audio Trans. in ATM/B-ISDN Systems...... 31 Question 21, WP2/15 - Signal Processing Aspects of Networks Optimized for Internet Protocol...... 33 SG15 WP1 & 2 Meeting Roster, June 21 – July 2, 1999, Geneva, Switzerland...... 36 ETSI TIPHON Meeting #14, July 19 – 23, 1999, Amsterdam, Holland...... 40 Working Group 1, Requirements...... 42 Working Group 2, Architecture...... 45 Working Group 3, Call Control...... 48 Working Group 4, Naming, Addressing...... 50 Working Group 5, Quality of Service...... 53 Working Group 6, Verification...... 55 Working Group 7, Wireless...... 58 Joint Meeting of ITU-T SG11, ETSI SPAN3, and TIPHON on IN for Voice/Multimedia over IP... 61 Security Sessions at TIPHON 14...... 62 TIPHON Meeting #14 Roster, July 19 – 23, 1999, Amsterdam, Holland...... 64 Q4/15 Rapporteurs, xDSL Network Access Transceivers, August 2 – 6, 1999, Nuremburg, Germany... 67 G.shdsl...... 67 G.vdsl...... 69 G.hs-bis...... 73 G.pnt...... 73 G.lite-bis...... 74 G.dmt-bis...... 76 G.ref-bis...... 76 G.test-bis...... 77 Acronym Definitions...... 78 1999 and 2000 Standards Committee Meeting Schedules as of August 20, 1999...... 82

REPORT OF TR-41.3.4 INTERIM MEETING, JUNE 21 – 23, 1999, VANCOUVER, BC P. Holland (Circa) is the Chair of TR-41.3.4. The objective of this interim meeting was to edit PN- 4462, Performance and Interoperability Requirements for VoIP Telephone Terminals, so that the draft document could be ready for committee ballot after the Ottawa TR-41 meeting in August. Two major contributions to the standard since the last meeting are sections to include ITU-T H.323 and IETF SIP (Session Initiation Protocol). In accordance with the TIA Intellectual Property Right policy, the Chair asked if there was any knowledge of patents, the use of which might be essential to the standards being considered. None were identified.

ACOUSTIC STANDARDS REVIEW OF PN-4462 R. Britt (Nortel), R. Magnuson (Siemens), and M. Knappe (Cisco) attended the TR-41.3.4 meeting to outline the status of PN-4352 (Transmission Requirements for Voice over IP and Voice over PCM Digital Wireline Telephones, based on TIA-579-A) and IEEE 1329 (Standard Method for Measuring Transmission Performance of Hands-Free Telephone Sets ) which is referenced by PN- 4352. It appears that both standards are on track and will be ready in time to be included with PN-4462. A presentation of the basic aspects of PN-4352 was made to raise awareness in TR- 41.3.4 of the importance of the requirements.

MEGACO TR-41.3.4/99-06-unn-E (S. Magnell, Dialogic) proposes text for parts of Section 5.1, Display and Keypad Requirements and Section 5.4, Internet Protocol requirements, based on the draft Megaco IP Phone Media Gateway (draft-batherwick-ietf-megaco-ipphone-00.txt). Discussion about this draft was primarily concerned with the use of several termination classes as described in TR-41.3.4/99-06-unn-E and about how the draft RFC should be submitted. Considerable time and effort was spent reviewing and editing the draft. Agreements: 1. Better alignment with Megaco use of terminations. Most user interface elements are now modeled as packages attached to root termination class. 2. Added DTMF tone generator (result from collapsing terminations into packages). 3. Added ancillary input package for extended keyboard (e.g., teletext input). 4. Refinement and clean up of signals, events, and other information. Discussion as to how the draft should be submitted was discussed in a conference call with T. Taylor (Nortel), the Media Gateway Control working group Chair. The purpose of the call was to determine how the next version of the Megaco IP-phone draft should submitted. Several options were considered, including the creation of a separate RFC; preference was to have the IP-phone draft be part of the main Megaco document. It was agreed that the best format would be to include the IP-phone as an annex and that it should be submitted as a Megaco draft rather than an individual draft. (This was done and the current draft can be found at http://www.ietf.org/html.charters/megaco-charter.html.)

DTE POWER VIA MDI G. Thompson (Nortel Networks), the IEEE 802.3 Working Group Chair, gave a presentation on the 802.3 Working Group and explained that a “Call for Interest for DTE Powering via MDI” (medium dependent interface or RJ 45 style jack in this case) would be considered at their July meeting in Montreal. If accepted, a study group would be formed to determine the approach to be taken by IEEE 802.3. While TR-41.3.4 had started to consider how phones should be powered and had noted that there were precedents within the existing IEC/ISO and ITU standards, it was agreed that the best approach would be to work with the IEEE to establish requirements.

To ensure that the initial version of PN-4462 does not leave the topic ambiguous, it was agreed to include a clause stating that powering via MDI should not be used until the IEEE Working Group has standardized the approach. Reporter’s Note: The IEEE 802.3 Working Group did establish a DTE Power via MDI Study Group. They have a web site at http://grouper.ieee.org/groups/802/3/power_study/public/index.html. This site also includes an email archive. The first interim meeting of the DTE Power via MDI Study Group will be Thursday, September 30 and Friday, October 1 in York, UK.

H.323 CONTRIBUTION A contribution to include H.323 in PN-4462 was submitted by H. El Gebaly and V. Kumar (Intel), D. Kumar and J. Honeycutt (Microsoft), and M. Korpi (Siemens AG). V. Kumar presented the contribution and led a discussion on the topic. It was agreed that H.323 would be an important addition to the proposed standard and that the contribution should be included, with a few minor editorial changes.

MINIMUM FEATURES LIST An objective of the proposed standard is to ensure interoperability between telephones provided by different manufacturers. One of the ways that this was to be done when PN-4462 was established was to ensure that compliant telephones had a minimum set of common features. TR- 41.3.4/99-06-unn-C (M. Korpi, Siemens) offers a list of telephony features and descriptions. During an initial discussion, there was strong opposition to a need for a minimum feature set; it was agreed that one should not be included. When the subject was revisited later in this meeting, further discussion identified interoperability concerns. The gist of the discussion was that while it is important for individual protocols to provide maximum flexibility, a product standard may have to provide a minimum set of capabilities to ensure interoperability. This is particularly important when products based on different protocols are used within the same system. The initial decision was changed; J. Honeycutt (Microsoft) led a discussion that produced the required, and recommended feature lists. The required features are: • Make a Call • Receive a Call • Transfer • Call Forwarding • Three-Way Conference • Caller ID Indication • Message Waiting • Redial • Speed Dial The recommended features that should also be provided include: • Transfer with Consultation • Multiple Call Appearances • Call Park • Call Pickup It was also agreed that the way the features are supported would be left to the implementers and would not be specified. An issue that was identified for Megaco phones was that the Media Gateway Controller (MGC) rather than the telephone controls the features, and that the proposed standard could not mandate MGC requirements. It was agreed that requirements for the common or well known names that a Megaco telephone would have to support should therefore be specified so that the MCG would be able to support the minimum feature list on a compliant telephone.

SIP CONTRIBUTION A preliminary review of the SIP contribution was done but time did not permit a detailed review. This will be deferred until the August TR-41.3.4 meeting. General comments were that SIP should be included as one of the protocols. To do this, the contribution must include unambiguous feature implementations to help ensure interoperability. Where SIP or the associated standards or recommendation do not do this, the requirements should be placed within the contribution and ideally submitted to the controlling body to be included in the base document.

PN-4462 TASKS

Section 2, Scope P. Holland (Circa) Section 3 Normalized References All members of the Working Group Section 5.1 Display and Keypad S. Magnell (Dialogic) Section 5.2 Acoustic Performance R. Britt (Nortel), P. Holland (Circa) Section 5.3 Ethernet Requirements B. Bell (Cisco) Section 5.4 Media Protocol Req. S. Magnell (Dialogic) Section 5.5.3 SIP Requirements D. Petrie (Pingtel) New Section Minimum Features Description J. Honeycutt (Microsoft), M. Korpi (Siemens) Section 5.5.1 Added well known names to P. Blatherwick (Nortel), B. Bell (Cisco) Megaco to support the minimum features list Section 5.5.2 Move H.323 Annex to the Body of V. Kumar (Intel) PN-4462 Section 5.6 Safety P. Holland (Circa) Section 5.5 EMI P. Holland (Circa) Section 5.8 Powering B. Bell (Cisco) Section 5.9 Environmental P. Holland (Circa) Phil Holland, Circa Communications

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TR-41.3.4 I NTERIM MEETING ROSTER, JUNE 20 – 21, 1999, V ANCOUVER, BC Phil Holland, Circa Communications TR-41.3.4 Chair

Circa Communications Ltd. Peter Baker [email protected] Circa Communications Ltd. Ted Lu [email protected] Circa Communications Ltd. SangEel Nam [email protected] Cisco Bob Bell [email protected] Cisco Norm Finn [email protected] Cisco Michael Knappe [email protected] Cisco Kirit Patel [email protected] Dialogic Corporation Steve Magnell [email protected] e-tel Corporation Cristian Vava [email protected] Intel Hani El-Gebaly [email protected] Intel Vineet Kumar [email protected] Marconi Communications Dave Brown [email protected] MCI WorldCom Robert Sparks [email protected] Microsoft James Honeycut [email protected] Nokia Rob Milne [email protected] Nokia Cristian Tabacutu [email protected] Nokia WBC Charles Mathieson [email protected] Nokia WBC Rob McGary rob.mcgary@nokia Nortel Networks Arlan Anderson [email protected] Nortel Networks Peter Blatherwick [email protected] Nortel Networks Roger Britt [email protected] Nortel Networks Geoff Thompson [email protected] Pingtel Dan Petrie [email protected] Siemens Austin Ron Magnuson [email protected] Siemens KN Markku Korpi [email protected] Simon Frazer University Jack McKee [email protected] Telogy Networks Manoj Sindhwani [email protected]

REPORT OF SG15, WORKING PARTIES 1 AND 2 JUNE 21 – JULY 2, 1999, GENEVA, SWITZERLAND This report from SG15 covers the activities of Working Party 1, Network Access, and Working Party 2, Network Signal Processing. Communications Standards Review is commencing coverage of WP 2, SG15 with this report. SG15 WP1 AND WP2 RECOMMENDATIONS APPROVED BY RESOLUTION NO. 2 PROCESS

Q Rec. No. Title Documents 7/15 G.169 Automatic Level Control Devices COM15 R29, TD- 015R1(PLEN) 4/15 G.992.1 Asymmetric Digital Subscriber Line (ADSL) COM 15-131, TD-007, Transceivers 016R1(PLEN) 4/15 G.992.2 Splitterless Asymmetric Digital Subscriber Line COM 15-136, TD-009, (ADSL) Transceivers 017, 023(PLEN) 4/15 G.994.1 Handshake Procedures for Digital Subscriber COM 15-134, TD-008, Line (DSL) Transceivers. Includes Appendix V, 010(PLEN), TD- Procedure for the assignment of additional 049(PLEN) G.994.1 parameters 4/15 G.995.1 Overview of Digital Subscriber Line (DSL) COM15-132, TD- Recommendations 026(PLEN) 4/15 G.996.1 Testing Procedures for Digital Subscriber Line COM15-133, TD- (DSL) Transceivers 022(PLEN) , TD- 027(PLEN) 4/15 G.997.1 Physical Layer Management for Digital COM15-135, TD- Subscriber Line (DSL) Transceivers 030(PLEN) 8/15 I.741 Interworking and Interconnection between ATM COM15 R29, TD- and Switched Telephone Networks for the 018R1(PLEN) Transmission of Speech, Voiceband Data and Audio Signals 3/15 V.300 A 144 kbit/s Data Circuit terminating COM15-137, TD- Equipment standardized for use on digital point- 031(PLEN) to-point leased circuits

OTHER SG15 WP1 AND WP2 APPROVALS The following Implementor’s Guides were agreed: Q Rec. No. Title Documents 6/15 G.763 Implementor’s Guide for DCME using G.726 and DSI TD-040(PLEN) 6/15 G.767 Implementor’s Guide for DCME using 16 kbit/s LD- TD-040(PLEN) CELP, DSI and fax remod/demod 5/15 G.776.1 Implementor’s Guide for Managed Objects for Signal TD-040(PLEN) processing Network 2/15 G.983.1 Corrigendum to Broadband optical access systems based TD-054(PLEN) on PON techniques

SG15 WP1 AND 2 RECOMMENDATIONS DETERMINED (I.E., FIRST PART OF THE RES. NO. 1 APPROVAL PROCESS)

Q Rec. No. Title Documents 7/15 G.168 Digital Network Echo Cancellers TD-044(PLEN)© 5/15 G.776.3 ADPCM DCME Configuration Map Report TD-045(PLEN) 2/15 G.983.2 ONT management and control interface specifications for TD-032(PLEN) ATM PON

SG15 PLENARY TOPICS P. Wery (Nortel, Canada) is the Chair of SG15. The SG15 plenary agenda is TD-001(PLEN) . TD-005(PLEN) is the List of Delayed contributions. TD-002(PLEN) provides useful general information: • Plans for alternative approval process (with shorter time frames) for technical recommendations not requiring Member States consultation were discussed. The goal is to approve the alternative approval process at WTSA-2000. World Telecommunications Standardization Assembly (WTSA), previously WTSC (WTS Committee), will consider these issues. WTSA-2000 will be held Sep. 27-Oct. 6, 2000 in Montreal, Canada. The framework for the alternative approval process is intended to be available in 2000. • TD-023(GEN) (TSB) is the new TSB Patent Policy. Specifically, Section 6 on “Discovery of Patents after Publication,” states that the TSB patent policy applies to patents identified after the Recommendation is approved. If the patent holder is unwilling to accept the ITU requirements, the TSB Director will advise the appropriate Study Group to consider revision or recision of the affected Recommendation(s). Appendix I includes the official patent policy; Appendices II and III are the new patent statement forms. • TD-021(GEN) , Procedure for prompt transmittal of Liaison Statements (TSAG, M. Sullivan, Telcordia), instigates the direct transmission of liaisons from sending rapporteur to receiving rapporteur without going through the TSB. • TD-019(GEN) , Interaction with the IETF (TSAG, R. Brett, Nortel), provides the details and encourages the ITU - IETF interaction. • TD-020(GEN) , TSB EDH Procedures (TSAG, K. Park, Protocol Engineering), notes the use of Micrografx Designer V 7.0 for drawings and the proposed change to Microsoft Office 2000 for word processing. TD-007(GEN) announces the Approval of Z.130 (Object Definition Language, ODL). ODL is a high-level design language used for computational specification in distributed systems, in particular the Telecommunications Information Networking Architecture (TINA). ODL supports all notations of X.920 (ODL IDL). In addition, it provides constructs for computational objects, multiple interfaces, stream and operational interfaces and objects groups. TD-010(GEN) from SG10 notes that new versions of the Recommendations for State Description Languages (Z.100), SDL with ASN.1 (Z.105), and MSC (Z.120) are planned for Approval in November, 1999. The new Recommendations do not provide 100% backward compatibility between Z.100 (3/93) and Z.100 (11/99) or Z.120 (3/95) and Z.120 (11/99). In a small number of cases, this may require updates to the machine-readable form of the SDL and MSC (Message Sequence Chart). It is expected that software tool suppliers will provide tools to make these changes automatically. TD-022(GEN) from SG9 notes that the new SG9 Recommendation J.web, Distribution of Sound and Television Programs over the Internet (Webcasting), was Determined and is planned for Approval at the September, 1999 meeting of SG9. TD-037(GEN) announces the availability of the 1997 ASN.1 Recommendations (X.680, X.681, X.682, X.683, X.690, X.691) and amendments to some of these Recommendations. Validation tools for 1997 ASN.1 Recommendations are freely available at http://www.nokalva.com and http://ans1.elibel.tm.fr. H. Zhao, Director of ITU TSB, gave a presentation on his vision of the future of the ITU-T. He noted the need for more ITU-sponsored forums. He suggests the greater use of press releases following Study Group meetings. An “associate member” category will be added for smaller companies that have a specific interest in ITU activities. WP1/15, NETWORK ACCESS The Chair of WP1/15 is A. Nunn (BT, UK). The reports of the last meeting of WP1/15 (COM15 R24©) and of the interim Rapporteurs’ meetings were approved. The WP1/15 Work Plan is given in TD-035(PLEN) . Liaison response statements are in TD-036(PLEN) . TD-033(PLEN) is the WP1/15 report of this meeting.

The questions currently allocated to WP 1/15 are:

Q Title Rapporteur 1/15 Access network transport R. Feigel (Bosch, Germany) 2/15 Characteristics of optical systems in local access networks T. Finegan (BT, UK) 3/15 DCEs for digital leased circuits R. Damm (Deutsche Telekom, Germany) 4/15 Transceivers for subscriber access systems R. Stuart (3Com, USA)

The ANT Standardization Plan and Work Plan activities support SG15’s role as Lead Study Group for Access Network Transport.

HOME NETWORKING D.528 (Intel and Conexant Systems) proposes the establishment of a new Question within SG15 to address Home Networking. It also proposes items for inclusion in the scope of any new Question on Home Networking. Reasons given in the contribution for favoring a new Question (rather than putting the work into Q4/15) include: • Q4/15 is already a large and active group and since few, if any, of the current attendees are experts in Home Networking, the addition of this topic to Q4/15 would necessitate an increase in attendance to a very unwieldy level. • The present Q4/15 work program already takes up a full five days at interim Rapporteur meetings and extending the duration of these meetings is undesirable. • Concern that the inclusion of home networking in Q4/15 may impact the progression of the work on all the different Digital Subscriber Lines (xDSL), and conversely that there would be adequate time available to progress the work on Home Networking. D.595 (Siemens AG) also proposes that a new Question in SG15 be defined to address the issue of Home Networking. The contribution notes that Home Networking technology, for example work of the Home Phoneline Networking Alliance (HPNA), is an area ripe for standardization, with an important impact on Very high speed DSL (VDSL) and other future network access technologies. It suggests that this effort be undertaken in SG15, within a new Question, so that the issue can be given the focused attention it deserves. Given the potential for crosstalk from home networks, the contribution proposes that it, within the new Question on Home Networking, should be studied in close coordination with Q4/15 which has responsibility for VDSL standardization. A British Telecom (BT) representative, on behalf of a number of network operators including Bezeq, Deutsche Telekom, France Telecom, Korea Telecom, KPN, Swisscom, Telecom Italia Group and Telia, read a prepared statement, which noted that commercial equipment is being developed world wide to enable high speed data distribution on telephony wiring within buildings, including the consumer market, for example, HPNA home network systems. While the network operators believe that this will have a positive effect on the growth of broadband services, it has been demonstrated that such equipment, without proper technical measures, causes spectral pollution and network harm due to crosstalk, which seriously degrades the performance of xDSL systems crucial for the growth of broadband services to the mass market. Operators asked that standards be developed to prevent spectral pollution of public access networks. There was support from some other network operators and manufacturers for this statement but some others considered that spectral compatibility with xDSL systems was not the only issue. Spectral compatibility with other access systems such as cable TV and wireless access need to be considered and this is outside the scope of Q4/15 and indeed SG15 as a whole. J. Dahl (MediaOne, USA) noted the need to coordinate spectrum compatibility with SG9 (cable networks), possibly wireless networks, and ISO/IEC JTC1 SC26. A long debate occurred on the issue of whether a new question is required for Home Networking. Finally, the management proposal in TD-002(PLEN) to do the Home Networking work in Q4 for the remainder of this Study Period, was agreed. It was also agreed to have an additional meeting to address higher layer aspects of HomePNA work. Views were expressed that Home Networking was not a

subject for the ITU-T but should be studied, for example, in ISO/IEC JTC1. It was also pointed out that the higher-layer aspects of Home Networking may require participation of other experts. Following a lengthy discussion, the Chair proposed that the guidelines offered by SG15 management and given in Section 6 of TD-002(PLEN) be adopted. This was accepted, and it was agreed to: • Initiate Home Networking related activities at this meeting under Q4/15 • Establish HomePNA related work plan - Recommendation(s) to be developed - Size, volume, complexity - Time Schedule • Assess remaining work (excluding Home Networking) under Q4/15 • Draft Question text(s) for next study period with a view to the most efficient and effective handling of remaining xDSL and HomePNA issues Home Networking was supported by SG15 management to be included in Q4/15. It was later determined that ANSI committee TIA TR-30.1 meetings on Home Networking would interleave with Q4/15 meetings to maximize the work on Home Networking, to be termed G.pnt (phone-line network transceiver). The goal is Determination of G.pnt in April 2000 and Approval at the WTSA meeting. It was recognized that cooperation with bodies such as ISO/IEC JTC1 and ITU- R may be required. The United States representative G. Fereno (US Dept. of State) noted that no inferences of support for a final ITU-T Recommendation, G.pnt, should be drawn from the lack of objection to the start of studies on technical issues that would need to be addressed. This arises from uncertainty over whether this work is in the jurisdiction of ITU, since at first glance it appears to relate to domestic rather than international subject matter.

ISSUES IN REFERENCING OTHER STANDARDS WORK An administrative problem emerged at the opening WP1/15 meeting. The United States representative G. Fereno, noted that ANSI is not an ITU-recognized organization. Therefore ANSI documents T.413 (ADSL), T1.101 (used to reference network timing reference [NTR]) and T1.601 (used to reference test loops) cannot be referenced in the six ADSL ITU draft Recommendations. It was agreed to have G.992 documents reference G.996.1 (G.test) for test references and to have G.test provide the test loop information. It is likely that this issue will be resolved, but for this Study Group meeting, the editors were charged with removing all ANSI references. S. Palm (Matsushita) reviewed G.992.1 (G.dmt) consisting of COM15-131© and TD-016(PLEN) . TD-016R1(PLEN) consists of a list of defects (identified by Q4/15) and typos (TSB transcription errors). TD-007(PLEN) identifies four changes required to remove T1 and IEEE references from G.992.1. C. Hansen (Intel) reviewed G.992.2 (G.lite) consisting of COM15-136©, TD-017(PLEN) and TD- 023(PLEN) . TD-017(PLEN) lists defects (identified by Q4/15) and typos (TSB transcription errors) and also includes a new Appendix C noting implementation issues with home networks. TD-023(PLEN) is a new Appendix II, Guide to scenarios for the implementation of the various procedures in G.994.1 and G.992.2. This provides examples of retrain and power cutback procedures. TD-009(PLEN) identifies two changes required to remove ANSI references from G.992.1. L. Brown (Motorola) reviewed G.994.1 (G.hs) consisting of COM15-134© and TD-010(PLEN) . TD-010(PLEN) captures the changes (18 items) agreed to at previous Rapporteur meetings and includes the latest corrections. TD-008(PLEN) identifies changes required to Annex A (backward compatibility with older DSL) to remove ANSI references to T1.413 issue 2 from G.992.1 and include them in a bibliography (Appendix IV). At the closing plenary, TD- 049(PLEN) was approved as G.994.1 Appendix V, Procedure for the assignment of additional G.994.1 parameters.

S. Abbas (Centillium) reviewed G.995.1 (G.ref), consisting of COM15-132© and TD-026(PLEN) , which adds the missing scope statement. Revisions to G.995.1 may be required in the future to support requirements of G.shdsl and possibly G.vdsl. M. Tzannes (Aware) reviewed G.996.1 (G.test) consisting of COM15-133© and TD-022(PLEN) , which provides a list of minor changes to the document. TD-027(PLEN) identifies changes removing ANSI references from G.992.1 and adds ten tables providing electrical characteristics of station wire. A. Johansson (Ericsson) reviewed G.997.1 (G.test) consisting of COM15-135© and noted two minor editorial changes. TD-030(PLEN) provides the editorial changes.

JOINT MEETING OF Q21/4, Q1, 2 & 4/15 A joint meeting of Q21/4, Q1, Q2 and Q4/15 was held under the chairmanship of A. Gillespie (BT, UK), the Q21/4 Rapporteur. The objective of the meeting was to clarify work required on management of the access network. Two documents of the Q8-series on access related transmission management were identified and have been added to Annex 2 of the Standardization Plan. Q2/15 reported on the current status of Recommendation G.983.1 and draft new Recommendation G.983.2 on the ATM-PON (Asynchronous Transfer Mode-Passive Optical Network) and Recommendation Q.832.2 on broadband optical access system management. The following points to be addressed by Q21/4 were agreed: 1. The ADSL element list in G.997.1 (G.ploam) should be checked against the relevant ADSL Forum specification. 2. Q.833.1 (ADSL) should reference the G.997.1 element list and the ADSL Forum GDMO (Guidelines for the Definition of Managed Objects). 3. Additional management work will be needed soon on G.shdsl; the ADSL Forum should be told about the provisional time scales and asked about their plans for this. 4. The detailed modeling of ATU-R User-Network Interfaces (UNIs) and of ISDN transport over ADSL will be covered in later work. 5. Q.833.2 (optical & hybrid) needs to be completed without delay because G.983.1 was approved last October and G.983.2 is proposed for Determination at the June 1999 meeting of SG15. 6. A protocol similar to the Simple Device Protocol considered in the Asynchronous Transfer Mode (ATM) Forum is used for the control of ATM-PONs, and Q.833.2 should relate this to the management interface. It was noted that a Recommendation on access WDM (wavelength division multiplexing) is not likely to be determined for at least a year.

WP1 LIAISON STATEMENTS The list of the liaisons received and sent is given in Annex 2 to TD-033(PLEN) ; the texts of the liaisons sent are in TD-036(PLEN) .

REVISED/NEW QUESTIONS FOR 2001-2004 STUDY PERIOD The initial draft of revised Q1/15 is given in TD-038(PLEN) (Chair, WP1/15). The new Question will continue to maintain and update the ANT Standardization Plan, the ANT Work Plan and the ANT Web presentation and coordinate with other Study Groups, other standards organizations, forums, and consortia. No revised text has been produced for Q2/15 and Q4/15, but it is proposed to draft text by correspondence for the April 2000 meeting of SG15. It is not envisaged to continue Q3/15 in the next study period.

PROCEDURE FOR THE ASSIGNMENT OF ADDITIONAL G.994.1 PARAMETERS

Based on a proposal from the Editor for Recommendation G.994.1, a procedure for assigning additional G.994.1 parameters was agreed. This was approved at the Plenary as an Appendix to Recommendation G.994.1. The text is given in TD-049(PLEN) .

ITU-T R ECOMMENDATION EXPERIMENT GROUPS (IREGS) TD-040(GEN) (Chair SG15) proposes guidelines for initiating ITU-T Recommendation Experiment Groups (IREGs) for the purpose of testing systems utilizing ITU-T Recommendations There was support for the concept, but concern that the guidelines do not take account of other bodies who may be performing interoperability testing. It particular, it was considered that the guidelines need to encourage IREGs to try to meet their goals by coordinating with other bodies to minimize duplication of effort. It was agreed to address these concerns in Section 3.3 (self- governance rules) of TD-040(GEN) . Q4/15 plans to initiate an IREG to evaluate the just completed G.99x ADSL Recommendations. WP 2/15, NETWORK SIGNAL PROCESSING The Chair of WP 2/15 is D. Sparrell (AT&T, USA). The results of the previous meeting of WP 2/15 (Oct 12-23, 1998) are in COM15 R23© and COM15 R28-29©. TD-040(PLEN) is the WP2/15 Report Part I. TD-039(PLEN) is the WP2 Document List. TD-041(PLEN) (summarizes the status of WP2/15 recommendations. TD-047(PLEN) contains the text of all the WP2 outgoing liaisons; TD-048(PLEN) lists the agreed interim meetings. The Questions currently allocated to WP 2/15 are: Q Title Rapporteur 5/15 SPNE Mgt Aspects C. Balogh (Tellabs, Finland) 6/15 CME Y. Naito (Mitsubishi, Japan) 7/15 EC & ALC Y. Tao (Bell Labs, USA) 8/15 ATM Interworking H. Kullmann (DTAG, Germany) 21/15 TIGIN J. Skene (Tellabs, Finland)

UK’S RESERVATIONS ON DETERMINATION OF G.168 The UK expressed concern that Recommendation G.168 (Digital Network Echo Cancellers) is being Determined before issues regarding V.34 fax described in TD-003(WP2/15) (SG8) have been fully investigated. So as not to hold up Determination of a Recommendation, it was proposed that V.34 fax issues be investigated at interim meetings and a suitable test (if appropriate) be developed to fix these problems. This test should be included in the Recommendation before Decision at the next SG15 meeting (Apr 2000). SG15 agreed to the proposal, with results and corrections discussed at the October Experts’ Group meeting. After this, G.168 will be submitted as a white contribution. IREG One IREG is forming under Q6/15 to validate the functionality and interoperability of draft Recommendation G.768, Digital Circuit Multiplication Equipment using 8 kbit/s CS-ACELP, digital speech interpolation and facsimile demodulation/remodulation. The life of this IREG is expected to be one to two years. Parties interested in this IREG should contact G. Mariano (AT&T, Tel: +1 732 420 4850, email: [email protected]) by September 9, 1999.

WP2/15 QUESTIONS PROPOSED FOR THE NEXT STUDY PERIOD Five questions were proposed by WP2/15 for the next Study Period. For the most part, the questions are continuations of the existing questions. However, some rearrangement of topics was done to optimize the workings of the rapporteur groups. Question 2A, Common Equipment and Control Aspects of Signal Processing Network Equipment , is a continuation of Question 5/15 and parts of Qs6, 7, 8, and 21. The background and justification for Q2A is:. The dominant services in today’s telecommunications networks

continue to be voice and voiceband services. Signal Processing Equipment (DCME, ECE, ALCE, VAME, IP-CME, etc.) are being used in nationwide and worldwide telecommunications networks. Signal processing functions such as low-rate encoding algorithms (G.723.1, G.726, G.727, G.728, G.729, etc.), automatic level control (G.169), and echo control (G.164, G.165, G.168), are being used in network equipment. This equipment typically has complexity and flexibility that result in significant administration and operation burden on network operators. During the last study period, SG15 approved Recommendations G.776.1 (Managed Objects for Signal processing Network) and G.776.3 (ADPCM DCME Configuration Map Report) to reduce this burden. The specific tasks for Q2A in the new study period include Recommendations for: • Configuration Map Interchange Format for SPNE (G.776.2) • Management Interfaces and Protocols for SPNE (G.776.5) • Managed Services and Functions for SPNE (G.776.6) • Management Architecture for SPNE (G.776.4) • Common equipment aspects of SPNE Question 2B, Compression and Signal Classification Aspects of Signal processing Network Equipment , is a continuation of Question 6/15. This question deals with the signal compression functionality and compression aspects associated with signal processing network elements. The responsibilities of this question include the study of functions such as signal classification, signal compression (through coding/decoding and digital speech interpolation), facsimile and voiceband remodulation, and issues such as compression tandeming avoidance and nx64 kbit/s transport. The background and justification for this question includes: Voiceband Signals Compression Equipment is utilized worldwide to optimize transmission bandwidth capacity. SG15 has been defining the recommendations for Circuit Multiplication Equipment and related TMN aspects. In this study period, SG15 has revised G.763 (DCME using G.726 and DSI), its Appendices, G.766 (fax remod/demod for DCME), newly established G.767 (DCME using 16 kbit/s LD-CELP, DSI and fax remod/demod), and is in the process of drafting new recommendations G.768 (CME using 8 kbit/s CS-ACELP, DSI and fax demod/remod), and I.733 (Voice cell assembly/disassembly compression equipment). As traffic characteristics change, there is a need to enhance compression equipment in the following areas: • Traffic signal classification schemes • Facsimile and data demodulation/remodulation processes (G.766) to accommodate higher bitrate modem signals (such as V.34) • Modify Rec. G.766 to handle T.30 NSF protocol of non-standard facsimile • Development of tandeming avoidance mechanisms for voiceband signals compression equipment • Development of channel assignment scheme for nx64 kbit/s unrestricted services • Definition of rules for automatic activation of forward error correction on demodulated facsimile traffic • Optimization study of delay through compression equipment • Definition of additional controls for when echo cancellation is built in to voiceband signals compression equipment • Addition of capability to request and provide end-to-end provisioning parameters in DCMEs • Addition of capability to request and provide traffic engineering and facility performance information • Real-time configuration access to voiceband signals compression equipment • Introduction of voiceband signals compression equipment in IP Networks • Evaluation/development of facsimile demodulation/remodulation techniques for voiceband signals compression equipment for IP Networks • Mechanism for reflecting ATM or IP congestion information to corresponding PDH access side • Mechanism for maintaining QoS in ATM and IP Networks Question Q2C, Network echo control, automatic level control devices, and interaction of acoustic echo controllers and network equipment , is a continuation of Question 7/15. This question is described as: What characteristics need to be specified and recommended for echo

12 Vol. 10.8 Copyright © CSR 1999 August-B 1999 COMMUNICATIONS STANDARDS REVIEW canceller equipment, and automatic level control equipment to provide good performance in existing GSTN and emerging ATM/IP networks? What are the issues related to network interaction of acoustic echo control devices and network equipment, and what should be recommended to ensure good performance in the network? The application of Automatic Level Control Devices is just beginning, and new issues will arise as these devices are applied to existing and emerging networks. G.169 will be revised to ensure adequate transmission quality. For interaction of acoustic echo controllers and network equipment, Recommendation G.167 on Acoustic Echo Controllers (AECs) contains text on the design of acoustic echo control devices and interaction problems between network equipment and AECs. Performance and compatibility issues related to speech quality should be done by the experts on speech quality and performance. Thus, the Recommendations on the terminal aspects of AECs and the interaction issues with network equipment should be split. This question proposes a revised G.167 that would focus on the network interaction issues; the terminal aspects should be dealt with in a new P-series Recommendation. Question Q2D, Transport Network Equipment for Interconnecting the GSTN to IP and ATM Networks , is a continuation of Questions 8 and 21. The description of this question is: What functionality, interfaces, performance requirements and functional tests need to be specified and recommended for Transport network equipment for Interconnecting GSTN and IP/ATM Networks (TIGIN) to provide good performance in the network? What impact do speech- processing issues related to this TIGIN equipment have on overall network performance? With the advent of cell-based networks using Internet Protocol and ATM, and as a result of the considerable growth in these types of networks, more and more speech traffic is expected to be carried over these cell-based transport networks. Cell-based transport of speech signals is a rapidly growing area of network development. For the next several years, much of this voice traffic will pass through equipment interconnecting the General Switched Telephone Network (GSTN) and cell-based networks. GSTN in this Question includes PSTN, N-ISDN, B-ISDN, and mobile networks, and cell-based networks include networks optimized for Internet Protocol (IP) as well as networks utilizing ATM transport. Because voice and voiceband services remain a significant part of overall telecommunications services, there is a need to ensure a high quality of service for speech carried in part or wholly by cell-based protocols. Recommendations for protocols exist or are being developed for converting and transporting GSTN-originated voice and voice-band data over cell-based networks. The interworking of these is covered by other Recommendations. It is the purpose of this Question to encompass these recommendations under various equipment specifications, and to include performance requirements and tests that will help ensure that the correct and appropriate functionality is present in this equipment. It is not proposed to redefine these existing protocols or define new ones. Question 2E, Experiments and Algorithmic Techniques of Signal Processing Network Equipment (SPNE) , is a continuation of parts of Qs 5, 6, 7, 8, and 21/15. This question deals with experimentation of SPNE-related Recommendations to ensure their correctness. It also provides the forum for the study of interoperability between SPNE and new voiceband traffic types. SPNE is an integral part of the PSTN. SG15 has been responsible for the definition of related Recommendations on Circuit Multiplication Equipment, Network Echo Cancellers and Automatic Level Control Equipment. As these types of equipment become more sophisticated, as new traffic types demand different treatments, and as the rapid changes in technology continue, it has become necessary to provide a forum for the experimental evaluation of SPNE Recommendations. The same occurs with the growing need for the experimental verification of interoperability between SPNE and new voiceband traffic types.

QUESTION 1, WP1/15 - A CCESS NETWORK TRANSPORT The Chair of Q1/15 is R. Feigel (Bosch, Germany). Following the completion of Issue 1 of the ANT Standardization Plan and an initial issue of the ANT Work Plan at the October 1998 meeting of SG15 (published in COM15 R25©), the objectives at this meeting were: • Update ANT Standardization Plan covering ITU-T, ITU-R and relevant external standards bodies activities. TD-025R1(WP1/15) provides the ANT Standardization Plan, Version 2: Input for SG15 6/99 meeting (based on COM15 R25©). • Progress ANT Work Plan, focusing on prioritization of standard activity and development of plans to handle missing standards and conflicting standards. TD-020(WP1/15) provides the ANT Workplan, Version 2: Input for SG15 6/99 meeting. This contains a revised contacts list. TD-024(WP1/15) provides the Web-based presentation of ANT Work Plan and Standardization Plan and Sitemap, with printed copies of the draft Web pages. The web pages are currently available (ties password needed) at: http://ties.itu/u/tsg15/sg15/wp1/q1/webANT. REVISION AND UPDATE OF DRAFT ANT WORK PLAN The list of contacts is restructured showing ANT-relevant identified Standardization bodies, present known contact persons with names and addresses, the location of Internet sites and the current status of contact. As a result of the last meeting decisions, some of the outside ANT standards bodies are contacted via “communication.” Unfortunately, no response has been received. The Rapporteur contacted some further groups via e-mail. Some progress can be reported: there is response from some CENELEC TCs, IEEE, ISO/JTC1, SCTE and EIA/TIA F0-6. A discussion with J. Carlo (TI), representative of IEEE and JTC1, took place. For the time being, documents of these groups related to customer premises structures as LANs are outside the area of ANT (see ANT Work Plan, 2. Definitions). This could be changed in the future since SG15 agreed on the new study item on HomePNA. Some minor editorial changes were made to the list “ANT Issues identified.” Since no progress was made on prioritization, missing standards, and conflicting standards during discussions in the last meetings as well as in the current meeting, it was decided to add a new list of “Ongoing Standardization Activities in the Area of Access Network Transport.” This list contains all activities in the various groups that have been brought to the attention of Q1/15 by incoming liaison documents or contributions. The list is a living document and will be publicly available as part of the web-based presentation of ANT. The list could even be changed using correspondence activities during interim periods between Study Group meetings. This list could lead to an intensive understanding of the actual work in the different Standardization Groups, which could result in a possible identification of gaps or overlaps. The liaison tracking, unchanged since 1997, was deleted and replaced by a new list, showing the incoming and sent liaisons with their dates, starting with this meeting. It was agreed to advance the draft ANT Work Plan to Issue 1. QUESTION 2, W1/15 - C HARACTERISTICS OF OPTICAL SYSTEMS IN LOCAL ACCESS NETWORKS Y. Maeda (NTT, Japan) acted as temporary Rapporteur of Q2/15 in the absence of T. Finegan (BT, UK). No interim meetings are planned. TD-010(WP1/15) , the report of the previous interim Rapporteurs’ meeting held in Orlando, USA, was approved. The main objective of this meeting was to complete a draft new Recommendation G.983.2 “ONT management and control interface specifications for ATM PON” for Determination. The revised version of draft new Recommendation G.983.2 in TD-010(WP1/15) was agreed as the basis for final editing. Q2/15 agreed that the proposed amendments to Recommendation G.983.1 (Broadband optical access systems based on PON techniques) contained in TD-026(WP1/15) (Editor, G.983.1) were purely editorial changes and should be corrected. It was agreed to forward the proposed Corrigendum to G.983.1 to the SG15 Plenary for agreement. The text is in TD-054(PLEN) .

COMPLETION OF REC. G.983.2 Q2/15 reviewed the enhancements and editorial corrections to draft Recommendation G.983.2 proposed in D.475 (NTT, Japan) and TD-033(WP1/15) (Editor, G.983.2), and agreed that the proposals should be considered in the editing work on G.983.2. The major enhancements are a change of title, a new summary, new appendices for F4/F5 maintenance flows and for traffic management options, and some editorial changes. Q2/15 set up an editing group chaired by S. Jiang (Lucent Technologies, USA) to produce the final draft for determination. The final draft as given in TD-032(PLEN) was Determined by the SG15 Plenary. This draft Recommendation contains a reference to an ATM Forum document. A statement declaring compliance with the requirements of ITU-T Recommendation A.5 will therefore need to be prepared before draft new Recommendation G.983.2 is submitted for a Decision.

NEW QUESTIONS FOR THE NEXT STUDY PERIOD D.505 (Korea) proposed a Dense Wavelength Division Multiplexing (DWDM) based Hybrid Fiber Twisted Pair access network architecture. A hybrid integrated SOA (semiconductor optical amplifiers) array module is considered as a DWDM transmission light source. The signals are VDSL modulated in the central office and transmitted over hybrid optical fiber/twisted pair lines down to each subscriber. The meeting agreed to take this information for a new study issue on the future DWDM-based optical access networks. The meeting also identified possibilities to enhance the ATM-PON system to support dynamic bandwidth allocation over the PON in order to accommodate IP traffic in an efficient manner. QUESTION 3, WP1/15 - DCES FOR DIGITAL LEASED CIRCUITS R. Damm (DTAG, Germany) is Chair of Q3/15; R. Damm replaced Rapporteur G. Sebek, who ihas taken a position with the ITU-TSB. Q3/15 was inherited from the former Study Group 14 after the previous Study Period. Throughout the present Study Period, there has been only minimal interest in the issue of DCEs for Digital Leased Circuits, with essentially only three countries participating in the discussions, and a likewise minimal amount of contributions. The group felt therefore that there is no justification for continuation of the Question into the next Study Period, and suggested canceling Question 3/15 at the end of the current Study Period.

DRAFT RECOMMENDATION V.300 COM15-137© is the text of the draft Recommendation V.300. The Rapporteur suggested minor editorial changes to the “Scope” section of draft V.300. These were accepted. He then explained the situation with the start-up procedure necessary to equalize different propagation delays in the two 64 kbit/s channels of a 128 kbit/s connection, and to identify the two channels. The text contained in Section 7 came into the draft Recommendation recently and was found to be incomplete. A proposed revised text is given in TD-032(WP1/15) . This description of the start-up procedure is believed to be unambiguous and complete so as to allow compatible implementations. It was noted that: • There is an intellectual property claim for the procedure described, with a patent pending, • A patent statement to that effect has been received by the ITU-T June 21, 1999, • The method described had been proven to work in practice by a large amount of relevant DCEs in the field, • No equivalent proposal exists yet for 144 kbit/s connections. It was decided to amend Section 7 of the draft Recommendation as proposed and to add a statement to the effect that the start-up procedure for 144 kbit/s connections is for further study. The agreed modifications to COM15-137©, draft Recommendation V.300, are in TD-031(PLEN) .

DRAFT RECOMMENDATION V.301 (EX V.2M) The draft text of V.301 as submitted to the Spring 1998 meeting of SG15 was quite incomplete and there has been no contribution since to enhance it. This was taken as an indication that the interest in a Recommendation for a 2,048 kbit/s DCE for digital leased circuits is very low, except in a few countries, and that it appeared not worthwhile to continue to work on the Recommendation. The suggestion of the group is to cancel any future work on V.301. QUESTION 4, WP1/15 - TRANSCEIVERS FOR SUBSCRIBER ACCESS SYSTEMS Q4/15 met three times in the interim period. The reports of these meetings are provided in TD- 004(WP1/15) , TD-017(WP1/15) , and TD-018(WP1/15) from the Q4/15 Rapporteur. The focus of this meeting was final editing of six Determined recommendations on Asymmetric Digital Subscriber Line (ADSL) and progressing Recommendations G.shdsl and G.vdsl. Additionally, a new Recommendation on Home Networking (G.pnt, Phone-line Networking Transceivers) was initiated at the Boston rapporteurs’ meeting in May. This new work was addressed and agreed by SG15. TD-002(PLEN) contains the terms of the agreements, provided as guidelines by the SG15 management team. The six ADSL Recommendations, G.992.1, G.992.2, G.994.1, G.995.1, G.996.1 and G.997.1 were all approved at the opening SG15 Plenary. The Q4/15 agenda (TD- 029(WP1/15) ) allocated over 80 documents, not including Liaisons for information allocated to this Question, to the specific areas of work. The Q4/15 Rapporteur session addressed the next generation versions of the six Approved Recommendations as well as G.shdsl, G.vdsl and two contributions, D.536 (BT, CSELT, Telia, Telstra) and D.537 (BT), addressing spectral compatibility issues for G.pnt.

INTELLECTUAL PROPERTY RIGHTS The following companies indicated that they have IPR on G.shdsl and G.vdsl Recommendations as well as G.99x bis Recommendations: Company IPR Company IPR 1. Adtran X 8. Matsushita 2. Alcatel X 9. Nortel 3. AMD X 10. PCTel X 4. Centillium X 11. SAS. X 5. Ericsson 12. Stanford U. 6. Level One X 13. Telia X 7. Lucent G 14. TI Lucent indicated they had made a General (G) IPR Statement to the ITU. Additionally, Alcatel, Ericsson, Matsushita, Nortel, Stanford and TI have indicated, as a goal, they expect to make an appropriate ITU Section 2.2 compliant statement in the future. They are reviewing the matter and will advise Q4/15 at a subsequent meeting.

NEW WORK The new work items and editors are shown in Table 1. The bis designation below does not necessarily indicate a new Recommendation will be generated. Modifications or additions to the now final Recommendation are also possible.

Rec. Recommendation Title Editor Name G.shdsl Single pair High speed Digital Subscriber Line (SHDSL) S. Blackwell Transceivers (Adtran) G.vdsl Very high speed Digital Subscriber Line (VDSL) S. Palm Transceiver (Matsushita) G.dmt bis Asymmetric Digital Subscriber Line (ADSL) Transceivers F. van der Putten (bis) (Alcatel) G.lite bis Splitterless Asymmetric Digital Subscriber Line (ADSL) T. Cole (AMD) Transceivers (bis) G.hs bis Handshake Procedure for Digital Subscriber Line L. Brown Transceivers (bis) (Motorola) G.test bis Testing Procedures for Digital Subscriber Line Transceivers M. Tzannes (bis) (Aware) G.ploam Physical Layer Management for Digital Subscriber Line --- bis Transceivers (bis) G.ref bis Overview of Digital Subscriber Line (DSL) S. Abbas Recommendations (Centillium G.pnt Phone-line Networking Transceivers --- Table 1. New Work Items for Q4/15. The scope of the (G.pnt) project is to develop interoperable, home-networked transceivers for point-to-point and multi-point data communications using existing subscriber premises wiring; the goal is being complementary to and compatible with access technologies. The transceivers enable home networking by allowing and providing for Ethernet packets to be transported over existing typical home telephone wiring. The G.pnt editor will be named at the Nuremberg meeting in August. The goal is to achieve Determination of this Recommendation by the last SG15 meeting of this study period in April 2000, and to achieve Approval at the WTSA meeting in October 2000. It was expected that the new work on Home Networking will be greatly facilitated by input from and coordination with ANSI TIA TR-30.1, where a project has been initiated as well to support the ITU effort. It was agreed that the TR-30.1 meetings will be focused to address the ITU Issues list for G.pnt. All ITU members interested in G.pnt are invited to these meetings. Thus, in addition to the meetings scheduled to address all work items in Q4, additional Q4 meetings focused only on G.pnt will be scheduled following several TR-30 meetings to potentially agree on the TR-30 G.pnt work product for Q4/15. This method of work was previously used very effectively in the development of Recommendation V.90.

G.LITE-BIS TD-038R1(WP1/15) is the issues list from the editor, T. Cole (AMD). This also includes issues related to G.gen-bis. Discussions on the direction of future work ranged from a simpler transceiver (Y. Goldstein, PCTel) to improving G.lite sufficiently to where it becomes G.dmt, but Q4/15 did not determine a direction. TD-038R1(WP1/15) is the revised issues list from meeting. D.512 (S. Abbas, Centillium) notes the market desire to support two voice calls (possible more) at bit error rates of 10-3 or better over G.lite-bis. A market study in the US by IDC in December 1998 indicated that 23.3% US households reported having two or more telephone lines with about 19.4% having two line, another 2.8% having three and 1.1% four or more. It was noted, by US West, that 10-3 BER is not sufficient for modem use which they see as a large use of second lines. Q4/15 appears interested in supporting multiple voice calls. It is an open issue whether a STM, ATM, or IP transport is desired. The editor noted that the ADSL Forum is actively looking at how voice calls may be layered. D.623 (A. Johansson, Sweden) indicates that Sweden still has concerns regarding performance (specifically reach) in G.992.2 and would like this area to be addressed in G.lite.bis. They suggest examining the use of trellis coding (as proposed in Appendix A of G.992.2) for G.992.2.

G.DMT-BIS F. van der Putten (Alcatel) was named as editor for G.dmt.bis. It was agreed to create a new Annex H (G.shdsl support in TCM-ISDN environment) in G.dmt. See the G.shdsl report below. No other changes to G.dmt were discussed.

G.GEN-BIS G.gen-bis is a place holder for papers that address multiple Q4/15 tasks. D.564 (S. Palm, Matsushita) generally proposes a document layering and format structure for the purpose of harmonizing components across various DSL recommendations. This is based on the ideas presented in BM-090 (C. Hansen, Intel, May 1999). D.565 (S. Palm, Matsushita), Power Control for xDSL, presents further thoughts on the needs for and benefit from a more standard approach to upstream and downstream power control for each of the future xDSL Recommendations, including G.shdsl, G.vdsl, G.dmt.bis, and G.lite.bis. Three power control procedures are described: G.hs and G.xdsl independent, G.hs duplex modulation with simultaneous power measurement, half duplex modulation and serial testing. This is an amplification of BM-055R1 (Boston, May 1999); D.491 (below) also relates. The basic goals and methods remain the same, but figures, components, and some example specification details are provided. D.634, Robust tone ordering and flexible pilot allocation (P. Reusens, Alcatel), proposes new study points for enhancements to mitigate single frequency interference. Single frequency interferers could include AM stations when they turn on, premise equipment (radio, TV, etc.), and sweep frequency generators used in testing. These enhancements should preferably be optional: • The frequency ordering of the DMT carriers should become less sequential and under control of the receiver. This ability of flexible reordering could be negotiated during G.hs, and exchanged as an improved (i, bi, gi) list during the same message containing the (bi, gi) list today. • During the initialization phase, the randomization of the pilot as a 4 QAM signal improves the immunity of the pilot in the presence of a single frequency noise. • During the “SHOWTIME,” the pilot tone can suffer a bad S/N including single frequency noise. This can be improved by asking the pilot to be reallocated. • Some receivers can synchronize on any pilot frequency, even when modulated with data. Therefore, the receiver should be able to ask the transmitter to replace the pilot by a regular data carrier. This will add extra line capacity. TD-025(GEN) , a liaison from ADSL forum, was presented by T. Starr (Ameritech). The ADSL Forum formed a working group on voice over DSL and plans to produce a requirements document for straw ballot from their Hawaii meeting, August 30 - September 3, 1999. TD-016(WP1/15) is a liaison from SG16 in response to a previous liaison from Q4/15 noting three models for voice over DSL: IP stream over DSL, ATM stream over DSL and DSL used to provide ISDN circuit services.

G.HS-BIS D.563 (S. Palm, Matsushita) proposes a frame retransmission enhancement for the next generation G.hs. The procedure is a backward compatible extension to existing G.hs; it is implemented as a new message type: request retransmission (RTX). The need for such a retransmission mechanism will likely be based on field performance experience. Whether this is added to G.hs or G.hs-bis also would need further review. The issue will be tabled until justified by field experience. The editor, L. Brown (Motorola), suggested improving Appendix I G.994.1 sample sessions in COM15-134©. However there was not sufficient interest to accomplish this at this time.

It was agreed that the procedure to update code points for G.994.1 will be added as an Appendix to G.994.1.

G.SHDSL (TO BE G.991.2) TD-027(WP1/15) is the issues list from the G.shdsl editor S. Blackwell (Adtran). TD- 028(WP1/15) is the work plan for the meeting. To support Japanese requirements for G.shdsl in the TCM-ISDN environment without making G.shdsl support multiple Annexes (similar to G.dmt), it was agreed to reference a new Annex H (G.shdsl support in TCM-ISDN environment) in G.dmt. The Japanese delegates noted their concerns that the Determination and Approval of the new Annex H in G.dmt and G.shdsl must be synchronized. D.489 and D.490 from the editor offer proposed text for the G.shdsl scope and Table of Contents. Further editing of these is required. D.491 (R. Goodson, Adtran) proposes that the modem will optionally probe the loop to determine the data capacity and allowed power backoff. G.hs will be used to transfer the probe results between the units, and to determine the data rate. The operator will have the option to force a specified data rate or to allow the unit to automatically select a data rate in an operator-specified range. In the same way, it proposes that the operator will have the option to force a specified power backoff or to allow the unit to automatically select a power backoff in an operator-specified range. In discussion it was agreed that the G.shdsl operator shall have the option (capability is required) of specifying power back-off control and may allow operation in a specified range. See also D.565 under G.gen.bis which reviews power control for xDSL. D.515 (K. Kikushima, NTT) proposes performance requirements for a TDD-based SHDSL system operating in the same cable as the TCM-ISDN DSL. The requirements are based on BM-041 , and are initial objectives. With reference to D.574 (Sumitomo Electric, Toshiba, Fujitsu, NEC, Matsushita, OKI Electric, Mitsubishi Electric, NTT), it was pointed out by simulation results in MA-075 that there are severe NEXT interferences between the TCM-ISDN and the transmission method currently proposed in the G.shdsl main body. To avoid the NEXT interferences, it was agreed in the Boston Q4/SG15 interim meeting that G.shdsl shall have a regional Annex and its duplexing method will be TDD synchronizing with TCM-ISDN. The line code selection for the Annex was left open. This paper proposes that “The line code for G.shdsl regional Annex in the TCM-ISDN environment shall be DMT.” This is based on the line code used in Annex C of G.992.1 (G.dmt). D.576 (P. Reusens, Alcatel), shows the crosstalk of Single-line High Speed DSL (SHDSL) on ADSL simulated in the following way: G.992 FDD-ADSL is degraded under SHDSL crosstalk with 24 HDSL or HDSL2 sources. This ADSL degradation is compared with the self-crosstalk with 24 ADSL sources. The introduction on a large scale of SHDSL in the residential copper network with repeaters to reach the longest lines will severely reduce the ADSL performance. It should be recommended that an SHDSL variant with lower bit rate be introduced, if used in conjunction with ADSL on lines above 3 km. The SHDSL with a lower bitrate (sub-rate of 2.3 Mbit/s or 1.5 Mbit/s) can feature a narrower bandwidth than the existing HDSL and HDSL2. Moreover an asymmetrical PSD mask for upstream and downstream will decrease the SHDSL crosstalk on ADSL, and can also reduce the adverse effect of ADSL on SHDSL. D.627 (R. Goodson, Adtran) proposes to adopt the frame structure and EOC from the HDSL2 draft standard for G.shdsl. A reduced length 10 bit sync word combined with SBIDs allows low frame sync errors combined with fast synchronization. A 24-bit octet based EOC channel allows fast and flexible signaling at 4 kbit/s and can be used to carry G.ploam without modifications. Three indicator bits allow fast signaling of alarm conditions with a fourth bit yet to be determined. The frame structure can be applied to both synchronous and plesiochronous options of G.shdsl. WD-003(WP1/15) is the document structure ad hoc report from the G.shdsl editor. The ad hoc group discussed the G.shdsl document structure, system reference model and table of contents. The agreed systems reference model is based principally on diagrams from the ETSI SDSL (BM- 078 ) and MA-054. The user plane protocol reference model is based principally on D.564, Figure

1. A draft table of contents provides for three regional annexes. The proposals in WD- 003(WP1/15) were accepted with some editing, as shown in TD-045(WP1/15) . It was agreed to change the name of the physical layer from transceiver (used to describe the entire Recommendation) to PMD (Physical Media Dependent). This will require a change in G.ref in the future. TD-044(WP1/15) is the ad hoc framing report from the G.shdsl editor. The following agreements were reached: • System Reference Model and User Plane Protocol Reference Model. • A basic structure for the Table of Contents. See WD-003(WP1/15) . • A basic frame structure based on the ETSI SDSL structure. • Use of the T1E1.4 HDSL2 EOC channel. The following details these decisions: • The first 14 bits of each frame shall be a Sync Word as described in ETSI SDSL. • 20 bits shall be reserved for the EOC channel • 4 fixed indicator bits shall be specified (for North America as specified in HDSL2). European definitions are yet to be determined. • The sbid1, sbid2 and spare bits shall remain unused in synchronous mode. • The HDSL2 EOC channel shall be used as the basis of the G.shdsl EOC channel (from D.627). The EOC channel’s External Message facility will be available to carry G.997.1, or other clear channel messaging. TD-044(WP1/15) also provides the SHDSL frame structure as Table 1. The G.shdsl committee approved the ad hoc agreements and the proposed Table 1 frame structure.

G.VDSL (TO BE G.993.1) WD-002(WP1/15) (S. Palm, Matsushita) is the G.vdsl work program. It also includes a discussion list with each paper organized by topic. TD-013(WP1/15) is the issues list.

REGIONAL AND MEMBER STATE POSITIONS ON VDSL D.535 (ETSI TM6, via K. Foster, BT) presents the ETSI functional requirements (Part 1) for VDSL going out for approval. This is an update to PO-037© (January, 1999). D.606© (K. Foster, BT) provides the ETSI VDSL specification (Part 2) transceiver specification which specifies two different line codes (SCM and MCM). Alliance and Coalition documents both appear in this specification. ETSI proposes spectral compatibility supporting both and a common higher layer. D.647 (TI and Lucent) reformats some of the PO-023 G.vdsl requirements (USA T1E1.4 requirements document, presented at the Q4/15 meeting in January 1999) so that each requirement can be mapped to a specific issue in G.vdsl. J. Cioffi presented this paper as from TI rather than from Stanford University. Stanford had applied to the ITU for membership as an SIO (scientific or industrial organization), however US West raised the issue that there are no universities as SIOs in the ITU and the Stanford application for ITU membership was turned down. D.521 (Mitel) indicates support for the DMT line code. This paper is a position from the Canadian delegation in support of DMT. After careful evaluation of the line-code proposals and prediction of the future use of VDSL, D.624 (Sweden) notes that the Swedish position is that DMT-FDD be a part of the G.vdsl standard. This is best done as a part of a dual line-code standard. Sweden believes that the DMT solution is a required component, but that it is not good to force both line-codes towards compromise solutions where the benefits of neither DMT nor SCM can be exploited.

G.PNT ISSUES D.537 (K. Foster, BT) reports practical tests in a realistic telco network scenario, showing that 1- Mbit/s Home Phoneline Networking Alliance (HPNA v1.0) signals cause severe disruption to VDSL services in nearby cable pairs of the Telco line plant, due to crosstalk within multi-pair cables. File transfer on the HPNA LAN caused continuous disruption to the VDSL system, and even simple operations such as refreshing the Windows Explorer view, while logged on to a network drive, caused large VDSL error bursts. In addition, Windows networking generates some traffic every few minutes for housekeeping purposes, without any user action, and these also caused error bursts on the VDSL system. In almost all cases where the HPNA interference had an effect on the VDSL system, the result was unacceptable performance of the VDSL system, with the bit error rate (BER) exceeding 10-7. Alternatively, the reach of the VDSL system would decrease from 1400 to 900 meters. D.536 (via K. Foster, BT, for FSAN members: BT, CSELT [Telecom Italia Group], Telia, Telstra) outlines the threat posed to VDSL by Home Phoneline (HPNA) systems based on the information in D.537. It reviews the options for overcoming this threat, and identifies a simple FDM between the two systems as the best approach. A specific proposal for a frequency demarcation at 10 MHz (above 10 MHz is HPNA, below is DSL) is made, and a PSD mask is suggested.

VDSL SPECTRUM MANAGEMENT D.589 (LM Ericsson) proposes that the VDSL system shall at least have PSDs, selectable by the Network Operator, according to the PSDs defined in ANSI T1E1.4, Very-High-Speed Digital Subscriber Lines-System Requirements, and ETSI TS 101 270-1 (1999-06), both of which have been submitted as contributions to Q4/15. D.590, PAR and statistical properties of VDSL signals (LM Ericsson), looks at the statistical properties of Quadrature Amplitude Modulation (QAM) systems using two and three transmission bands in the same direction and compares this with the properties of the Discrete Multi-tone Carrier (DMT) signal. Going from single band to multiple band for CAP/QAM will increase the requirements on the analog front-end. Some of the advantages such as much lower Peak to Average Ratio (PAR) for the CAP/QAM system will then be reduced. Discussion about analog front-ends has lately focused on the number of bits in the Digital to Analog (D/A) and Analog to Digital (A/D) converter and the die size of the analog chip. As a systems integrator, Ericsson is not that worried about this relatively small difference in requirements between the two systems. However there are other areas that can have a considerable higher level of impact on the system complexity. One of the most important issues for the system will be the needed flexibility in allocation of the transmission bands. If great flexibility is needed, there will be a severe impact on the choice of suitable technology. Some of the issues that need to be discussed to sort this out are: • Maximum number of allowed frequency plans inside North America; this is closely related to the spectrum management project. • The reach penalty different countries could accept to allow for a world wide frequency plan. The network topology and disturber situation will vary between countries because of the planning rules used for cables, topologies, and heritage systems. This will occur because the optimum frequency plan will vary between different countries. The question becomes, how big of a reach reduction can a country accept as a result of sub-optimum band allocation in return for a world wide frequency plan? • If a world wide frequency plan cannot be agreed on, to what extent and with what resolution can a portable modem support flexible band allocations? There are three options to solve the frequency separation: analog fixed separation filters, tunable analog filters, and pure digital band separation. If some flexibility is needed, having some extra fixed analog filters or using tunable analog filters is viable. But if a high degree of flexibility is needed, the number of analog filters would increase the complexity of the system and a pure digital separation would be more advantageous.

D.626 (Siemens) indicates how to divide the total available bandwidth between the downstream and the upstream. It suggests uses of the differential capacity criterion to determine the optimal number of bands and the optimum bands to be used for the universal band allocation for FDD VDSL. The applied criteria are independent of line code. The conclusion is that more than four bands does not provide significant advantage. D.645 (J. Cioffi, Stanford, for TI) was for information only. This document provides several simulation results for Very high speed ADSL (VDSL) frequency-division duplexing plans for DMT VDSL (MA-050r2 ). Regional VDSL system requirements in PO-23R1 (T1E1.4), D.535© (ETSI), and D.514 (NTT) are all investigated. Duplexing plans exist for DMT that allow requirements to be met in all three regions, although these plans can differ substantially for both asymmetric versus symmetric and regional requirements. A conclusion is that no single fixed duplexing plan is sufficient and the data within supports the proposals in D.646 for resolution of duplexing. D.646 (J. Cioffi, Stanford, for TI) proposes a two-step process to work towards a frequency- division duplexing spectrum plan for VDSL. The first step is the internationally agreed specification of a frequency grid from which upstream and downstream cut-off frequencies would be selected, facilitating standardized VDSL transceiver design. The second step encourages regional selection of upstream and downstream frequency masks as necessary from the grid. Such a two-step process is justified because it allows VDSL designs to be robust with respect to a difficult set of internationally varying, and regionally varying, spectrum-management requirements. D.650 (Analog Devices, Broadcom, Globespan, Lucent Technologies, General Instruments/NLC Corporation) proposes a universal band allocation for VDSL using frequency division duplexing (FDD). The proposed allocation includes two possible transmission bands in both directions. The proposal is noted to be both line code independent and TC layer independent. It also meets the spectral compatibility requirements for other xDSL services and provides mixed VDSL services in the same cable binder including unbundling. D.656, (Broadcom) Analog front end dynamic range requirements for programmable spectrum VDSL systems, states that 11.5 bits of A/D resolution are required for DMT with analog filtering, and that 15.5 bits are required for DMT with digital duplexing. (Editor's note: G. Ungerboeck recently joined Broadcom and presented all the Broadcom papers in place of the author D. Jones.) Spectral programmability for VDSL is a concept that can be divided into degrees. Spectral programmability of a degree that allows for FDD implementation including fixed analog diplexing filters is appropriate for VDSL. Extending the degree of spectral programmability beyond the point serviceable by analog diplexers is ill-advised from an analog front-end complexity perspective. This is true whether the complexity increment takes the form of an increase in ADC precision or the introduction of hybrid analog/digital echo cancellation to VDSL. VDSL systems containing more than four or five bands will also have excessive front end requirements, even without spectral programmability. Spectral programmability should also be limited in degree because of spectral compatibility concerns, especially in an unbundled environment. The report of the G.vdsl spectrum ad hoc is TD-043(WP1/15) . Although no spectrum plan was agreed, the following criteria for reaching such a decision are identified; this is a step forward: • A single world-wide frequency plan • Asymmetric and symmetric services in the same binder • A fixed number of upstream and downstream bands • No more than eight bands in the VDSL frequency region

VDSL SPLITTER/ADC/DAC D.625 (Siemens) reviews the current state-of-the-art of Analog-to-Digital converters (ADCs) for VDSL, focusing on requirements for SCM and DMT, respectively. Should 12-bit ADCs be required for VDSL, D.625 states it will take another five years until the converters are mature for mass production. However the inherent resolution difference of 2 bits will significantly increase the analog complexity in terms of die size and power consumption at any time. D.644 (J. Cioffi, Stanford, for TI) was for information only. To meet the high-performance system requirements of VDSL, ADCs with resolutions of up to 12 bits at speeds as high as 35 MS/s (or

70 MS/s if double-over-sampling is used) may be necessary with all transmission methods with digital frequency-division duplexing. This document investigates the implementation feasibility of such ADCs. Specifically, it presents a brief survey of the current state-of-the-art in ADCs, presents some of the key technical issues to be addressed concerning future improvements in ADC performance, and makes some comments related to the VDSL application. D.651 (V. Oksman, Lucent) compares the required resolution of an ADC when analog or digital band-pass filters are used for band separating in Frequency Division Duplexing (FDD) based VDSL. It considers different band allocation scenarios, mostly for VDSL to the cabinet (FTTCab) deployment, and analyzes reduction of the received signal dynamic range when analog filters are used. The obtained results are line code independent and show that a possible relaxation in ADC requirements may be achieved if analog band-pass filters are used instead of digital ones. When using an FDD band allocation scheme, analog band-pass filters can be replaced by digital filtering, but at a cost. An estimation of this cost gives about 5 additional bits in the ADC for long range loops, 3 additional bits for medium range loops and 1 additional bit for short loops for practical scenarios. The benefits of using analog band-pass filters are reduced by 1 bit for the long range loops if strong in-band RFI ingress is be considered. D.652 (V. Oksman, Lucent) estimates the required resolution of an ADC and DAC for a DMT/FDD based VDSL system. The system parameters were obtained from the current VDSL DMT proposal (MA-050R1 , Melbourne, April 1999) with no usage of analog band-separating filters. The contribution recommends using analog band-separating filters, which allow a sufficient relaxation to ADC/DAC resolution requirements and bring feasible values. There was extensive discussion on the effects of mild analog filters on digital duplexing approaches (e.g., Zipper-interleaved multiplexing), which reduced the divergence of views of single- and multiple-carrier supporters.

VDSL REGIONAL REQUIREMENTS D.513 (NTT, Matsushita, Sumitomo, OKI, Mitsubishi, Toshiba, Fujitsu, and NEC) proposes the VDSL spectrum in the TCM-ISDN environment. It proposes FDD with the use of the A-ON spectrum (up to 1.104 MHz) be used in the TCM-ISDN environment. TDD 400 Hz synchronized with TCM-ISDN DSL below 1.104 MHz is also proposed if required. D.513 was accepted. D.514 (NTT) proposes performance requirements for a VDSL system operating in the same cable as the TCM-ISDN DSL. It proposes a VDSL transmit PSD mask (F1 = 1.104 MHz) and includes the amateur radio bands. D.653 (Broadcom) notes that ingress measurements made in the field on actual Regional Bell Operating Company (RBOC) loops has revealed the presence of bursty ingress from mobile sources, and at statistical levels of occurrence seemingly much higher than that for amateur transmissions. A very high percentage of the VDSL band overlaps licensed transmissions from fixed, aeronautical, and maritime mobile sources. These transmissions are bursty in nature, and taken in the aggregate, are extremely unpredictable with respect to frequency location. Ingress from these mobile sources is an important impairment source for VDSL, and perhaps more statistically relevant than amateur ingress. Because of these facts, D.653 proposes that models be developed and included in VDSL Systems Requirements document for ingress from mobile sources. It also proposes that the ETSI broadcast ingress sources above the commercial AM band be included.

VDSL COSTPLEXITY Costplexity (a portmanteau word) was offered by the G.vdsl editor. It refers to the joint issues of cost and complexity. D.594 (Siemens) presents the measured performance of an FDD Single-Carrier Modulation (SCM)-based VDSL system. The evaluated system is composed of standard technology devices. Results show that ANSI and ETSI requirements are achievable without additional assumptions about future technology improvements.

D.633© (Alliance, via Alcatel) proposes a Physical Medium Specific specification for VDSL. The specification describes both the Physical Medium Dependent (PMD) and Transmission Convergence-Physical Medium Specific (TC-PMS) layer. This proposal specifies a duplexing method based on FDD. The specification supports the operation of TDD (time division multiplexing) below a specified frequency (the selection of this frequency is programmable), and FDD above that frequency. The duplexing requirements are captured in a single specification, eliminating the eventual need for a separate annex to accommodate possible regional duplexing requirements. PO-023R1 (USA) and PO-037©, VDSL System Requirements (ETSI), present a challenging task for the modem designer because they specify as VDSL requirements a number of operating data rates and downstream:upstream ratios over a wide variety of channels. D.639, Measured performance of DMT based VDSL (TI), presents measurements taken at several sites around the world that show that DMT is capable of meeting these requirements with a single modem. D.640 (TI) presents a method by which the performance of DMT-based FDD VDSL modems can be extrapolated from the measured performance of a DMT-based TDD VDSL modem. Using this method, TDD modems can be used in performance tests, the results of which may be used to compare line code alternatives. It is proposed that the method described in this document be agreed by SG15/Q4 as a valid method by which FDD DMT VDSL performance can be evaluated. D.641 (TI) estimates the digital complexity of the current DMT VDSL line code proposal by looking at available solutions and by scaling them in current and future technologies. D.641’ s purpose is to show that DMT VDSL is a competitive and deployable solution today. D.643 (TI, Alcatel USA, Globespan, Nortel Networks, Samsung, IBM, NEC America) is a contribution from companies with market acknowledged competence and expertise in both DMT- based twisted-pair access systems and semiconductor technology. While digital complexity of a multi-carrier transceiver chip may be slightly higher than that of a single-carrier transceiver chip, the difference in complexity does not impact the overall VDSL system solutions. With the current 0.15 micron technology and heading down to sub-0.1 micron technology in the very near future, the difference in complexity becomes very small. D.654© (Broadcom) reports on measured performance results for a QAM-based asymmetric VDSL modem design currently being used in field trials and service deployments around the world. The VTU-O Utopia-to-twisted-pair modem consumes 1.6 watts of power and meets the footprint requirements necessary for use in dense, remotely-powered commercial platforms. The VTU-R modem power consumption is 2.0 watts. Measured results indicate that these modems achieve the combination of bit rate and reach necessary for commercial deployment. D.659 (Lucent) contributes the following: in order to keep overall VDSL system complexity to a minimum, the VDSL circuit, including the chip set and all external components from twisted pair to Utopia II (ATM interface, gamma reference point), should do the following: (1) keep per-circuit complexity to a minimum; (2) keep power dissipation below 1.5 W now and below 1.0 W by 2001; and (3) keep board space below 6 in2. These three issues are proposed as requirements when selecting a VDSL system to be standardized.

VDSL COMPARISONS D.577© (Alcatel) notes that the sample distribution of a single carrier system is studied at the transmitter and at the receiver and compared with DMT. It is shown that the shape of the distribution changes as the signal is sent through a non-ideal channel. In particular, larger crest factors occur after passing the channel. This effect seems to be strongest for the longest loops. Although the distribution is still narrower than a Gaussian distribution, the difference between CAP/QAM and DMT modulation is smaller than one would expect on the basis of a direct comparison between sample distributions. D.593 (Siemens) suggests that a comparison of the size difference that can be expected between splitters designed for ADSL and VDSL indicates that the goal of a universal POTS splitter is impractical. Siemens suggests that these considerations, which are independent of the question

of VDSL line code, cast some doubt on the economic attractiveness of the scalable DSL concept. Alcatel noted that they find the splitter sizes suggested unrealistically large. D.642 (TI) indicates that the complexity of QAM and DMT technologies is similar based on meeting internationally agreed system requirements and that the DMT technology offers greater flexibility. D.648 (J. Carlo, TI) makes a high-level comparison between DMT and single-carrier modulation for the VDSL application, on the basis of performance and complexity, and introduces two comparison criteria of importance to system operators and end-users: • Flexibility of frequency use • Adaptability of data rate D.649 (IBM, Globespan) is a tutorial. J. Cioffi noted that he also is an author of this paper and that he supports this contribution as a possible compromise, not as an alternative line code. CAP/QAM, DMT, and filter-bank modulation techniques for VDSL are put in perspective. Filter- bank systems may represent a framework within which the convergence of CAP/QAM and DMT- based modulation systems can be achieved. Filter-bank modulation may offer advantages that go beyond those of the CAP/QAM and DMT schemes taken individually. D.649 describes the basic principles of a filter-bank modulation technique called filtered multitone (FMT) , and presents an analysis of its performance for VDSL transmission. FMT modulation is a filter bank modulation technique where the M-branch filters have equal bandwidths and are designed to achieve a high level of subchannel spectral containment. In other terms, the filters are designed such that at the output of each subchannel, the level of interchannel interference may be considered negligible as compared to the level of other noise signals. In FMT, a high level of spectral containment is achieved by subchannel spectral shaping; per-subchannel signal equalization is employed. In discussion, several companies noted that they had previously reviewed similar technology. Concerns were raised over the untested nature of this modulation. It was noted that many different modulations are possible but which of them offers the best trade-off of complexity and performance is the difficult issue. IBM agreed to bring in papers expanding on the advantages of FMT. D.655 (Broadcom) describes QAM and DMT simulation results designed for comparison with measured results of a deployed QAM modem design. In order to provide a meaningful comparison, the QAM and DMT simulations both use the same spectral allocation as the QAM hardware already tested. The simulation results indicate a small performance advantage for QAM relative to DMT, because of the latter’s effective loss of low-SNR bandwidth. The simulation results also show that the hardware modem design is operating within 0.75 dB - 1.5 dB of theoretical limits, a gap which can be readily closed. D.658 (Broadcom) makes a summary comparison of the SCM and DMT line codes for VDSL. The SCM and DMT proposals rate an approximate tie in many categories. SCM has the advantage in the categories of minimum latency, complexity, time-to-market, and field experience. DMT has the advantage in the category of high-degree spectral flexibility. However, Broadcom believes this maximum degree of spectral flexibility is undesirable from both plant spectrum management and analog complexity perspectives. VDSL INTEROPERABILITY D.575©, Interoperation of G.VDSL with ADSL (Alcatel), discusses a scenario where ADSL services from the CO share the same cable binder as VDSL/ADSL services offered from the cabinet. It is shown how ADSL services can be offered from the Cabinet equivalent to those offered from the CO. At the cabinet, the ADSL protocol can be supported either by genuine ADSL line cards or by VDSL line cards capable of compatible operation with ADSL. Spectral compatibility between the CO-based ADSL service and Cab served ADSL service can easily be guaranteed by controlling the transmit spectrum of the ADSL signal. D.575© concludes that ADSL can be served from CO, Cabinet or DLC system. As a consequence, for each considered VDSL deployment scenario, interoperation between VDSL and ADSL is a highly desirable feature.

Recent contributions have proposed VDSL/ADSL backwards compatibility, through the concept of a scalable DMT VDSL system. Such proposals require the application of ADSL’s 4.3125 kHz DMT sub-channel spacing to VDSL as well, with the VDSL FFT size growing to 4096 points for 8.832 MHz of bandwidth and 8192 points for 17.664 MHz of bandwidth. Because of tight constraints on ONU power consumption, circuit density, and architectural competitiveness, and using an aggressive analysis based on Moore’s Law, D.657 (Broadcom), demonstrates that high- speed mass-deployable VDSL products based on this concept will not be available for 4 - 6 years. This is in contrast to high-speed VDSL based on single carrier modulation, which is already being deployed in commercial service offerings. There was considerable discussion on this issue. Siemens noted that the VDSL splitter independent of the ADSL splitter at the network side (xTU-C) was a separate constraint on VDSL/ADSL compatibility. No conclusions were reached.

G.TEST-BIS TD-012(WP1/15) includes ADSL Forum contribution 99-107 “Proposed test loops to be included in ADSL Dynamic Interoperability Testing.” It presents data from Ameritech. Testing of ADSL has shown that bridge tap length and location on loop (nearer to ATU-R is worse downstream) has a significant affect on performance. TD-012(WP1/15) proposes the addition of fifteen test loops to better measure and compare ADSL performance. A 1997 Subscriber Loop Characteristics Study from Bellcore based on a survey of loops from Ameritech has shown that a bridge tap is quite prevalent. Approximately 75% of all loops have some type of bridge tap and approximately 33% of all loops have bridge taps between 250 and 500 feet. Note that this bridge tap length coincides with the “sour spot” (~400 feet of bridge tap) for negative performance on ADSL transmission as noted in TD-012(WP1/15) . It was not clear if the 15 requested test loops are proposed for conformance (Q4/15) or performance testing (currently being worked in TR-30.3); Q4/15 was not ready to agreed to the need for additional test loops for conformance testing. However the additional test loops issue was added to issues list. A liaison to the ADSL Forum (TD-036(PLEN) , Annex 2) reflects these decisions. QUESTION 5, WP2/15 - MANAGEMENT ASPECTS OF SIGNAL PROCESSING NETWORK ELEMENTS The Q5/15 Rapporteur is C. Balogh (Tellabs, Finland). The main objective of the meeting was to advance the study on G.776.3, ADPCM DCME Configuration Map Report. G.776.3 was Determined as TD-045(PLEN) . An Implementer’s Guide for G.776.1, Managed Objects for Signal processing Network, was approved as TD-040(PLEN) . The experts also agreed to continue the Question in the next study period; to that effect, a draft text for the Question was prepared. The Question is being enlarged to include the common equipment aspects of SPNE (Signal Processing Network Equipment).

G.776.3 AND G.776.1 Ad hoc groups were convened to work on Section 5, Recommendation Overview, DCME clocks and Appendix I. Appendix I was agreed; it provides an example Configuration Map Report. D.544 (Tellabs Oy) identifies several attributes found in G.776.3 but not found in the G.776.1 Attributes appendix. The group discussed each attribute and decided to add the following to G.776.1 Attributes appendix: q50aSimpDLConAbcd nssNotSupportedManufacturerCode nssNotSupportedMachineCode

It was determined that the following attributes were not required in G.776.3: Facsimile_System_Remod PRI_T1_Carrier_Fail_Set_Delay PRI_T1_Carrier_Fail_Reset_Delay Error_Performance_Interval Additionally, the following attributes were created for G.776.3 and need to be added to the G.776.1 Attributes appendix: priAlarmResetDelay facsimileDemodulationDS0 bcAssignment alarmSeverityClassification The revised text of G.776.3 is found in TD-014R1(WP2/15) . Decision is planned for G.776.3 at the SG15 meeting in April, 2000. The above changes to G.776.1 were approved as an Implementors Guide, in TD-040(PLEN) the WP2 report. QUESTION 6, WP2/15 - CIRCUIT MULTIPLICATION EQUIPMENT AND SYSTEMS The Q6/15 Rapporteur is Y. Naito (Mitsubishi Electric Corp., Japan). The main objectives of the meeting were to advance the study on G.768 (8k DCME), I.733 (VAME) and the new item of CME optimized for IP (IP-CME). Twenty experts participated the meeting and total of 37 documents were submitted for discussion. Two Implementer’s Guides for Recommendations G.763 and G.767 were presented, mainly for clarifications, and were approved by SG15 (both in TR-040(PLEN) ). Unfortunately the draft Recommendations G.768 and I.733 were recognized not to be matured enough to ask for Determination. It was agreed to continue drafting, with Determination expected at the next SG15 meeting (April 2000). Discussion on the new study item of CME optimized for IP (IP-CME) was initiated and a list of study items was drafted. Two interim meetings were proposed; a workshop for CME was also suggested in conjunction with the latter meeting.

IMPLEMENTER’S GUIDES Submission of draft Implementor’s Guide for Recommendations G.763 and G.767 for SG Approval was based respectively on D.540 (AT&T), clarifying text accepted February, 1999, and D.541 (AT&T), corrections, accepted February, 1999. The generator polynomial for BCH was agreed to be included.

CME OPTIMIZED FOR IP D.510 (KDD) presents results of performance evaluation of four IP-based multiplexing schemes: • Scheme A, a single IP packet is generated for each data block. • Scheme B, a single IP packet is generated to carry multiple sequenced data blocks (Lb indicates the pre-specified maximum amount of data) • Scheme C, multiple streams are encoded into a singe IP packet (Tc is the defined packet time). • Scheme D is similar to scheme C, with Ld, the number of short packets in the IP packet replacing Tc. In scheme A, the output delay is small when the number of channels is small but quickly becomes too large due to increasing congestion. Simulations showed that, by allocating IP packets to multiple data blocks in B, C and D, the RTP packetization delay becomes large until a certain pre-specified data size or time limit is reached, and then the RTP packet output delay becomes small. As the number of channels becomes large, the RTP packetization delay in scheme D becomes smaller by taking advantage of increasing parallelism.

G.768 TD-019(WP2/15) , the early draft text of Rec. G.768, together with the latest updates, was reviewed by the editor (G. Mariano, AT&T). G.768 is an extension to G.763 (DCME using 32 kbit/s ADPCM and DSI) and G.766 (fax remod/demod for DCME), as it specifies the deviations of the 8 kbit/s DCME from G.763. This Recommendation is expected to be Decided at the next SG meeting. Discussion on the IC/IO experiments occurred and an experiment on G.768 DCME was agreed. G. Mariano (AT&T) was assigned as the coordinator. I.733 TD-020(WP2/15) is the draft text of Rec. I.733, Voice cell assembly/disassembly compression equipment. The purpose of Voice on ATM Multiplication Equipment (VAME) is to provide means of augmenting the traffic capacity of ATM facilities operating between International Switching centers (ISCs) and sources of ATM traffic. In addition to providing traditional DCME functions, the equipment will have capabilities such as ATM multiplexing to optimize bandwidth utilization. Three Mitsubishi contributions were reviewed: • D.608 proposes consideration of Coding Format profile arbitration and related issues. • D.609 highlights the difference in fax remod/demod controlling procedures specified in G.766 and I.366.2 and suggests further investigation. • D.610 proposal to add V.33 codepoints for Fax remod/demod. The editor presented additional comments on the draft reflecting the discussions of the editorial group. It was agreed to add V.33 modem to the table of modulation type codepoints as an option and send a liaison (TD-047(PLEN)-L to SG13 proposing the addition of a V.33 modulation codepoint (Table M-2/I.366.2, 0100) to G.366.2. It was agreed to continue the drafting and seek Determination at next SG meeting. ITU TIES subscribers can find draft text of I.733 at http://ties.itu.int/u/tsg15/sg15/wp2/stable_text/gvame/i733 (password required).

LIAISONS TD-001(GEN) , liaison from Q1/2 on the expansion of country code in Rec. E.164. It was confirmed that the revision will do no harm to Rec. G.765 (Packet circuit multiplication equipment) since it does not use the country code. The information was passed to Q13/15 (Management functions and services of transmission systems and equipment) to generate a liaison. TD-009(GEN) is a liaison from SG10 asking for the use of description techniques in ITU-T Recommendations. It was recognized that the description languages are used in Recommendations G.763, G.764 (Voice packetization - packetized voice protocols), and G.766. The information will be conveyed to SG10 as a liaison from another WP. TD-013(GEN) (SG13, as the IP-related SG) reports on SG13’s work. They are taking an even- handed approach: raising questions on the different approaches (broadband and IP) and presenting the work in progress in the ITU-T. TD-014(GEN) requests information on IP related work in SG15. Q6/15 responded, including the list of study items for IP-CME. This was included in the liaison to SG13 prepared by Q21/15. TD-004(WP2/15) from SG11 on Tandem DCME Control reports that Q.55 (formerly Q.spne), Signaling between SPNE, was Determined in March, 1999. Q.55 might be able to provide the necessary protocol and signaling capabilities for control of DCMEs, as well as controls for establishing 64 kbit/s clear channel calls (e.g., similar to Q.50 control). TD-047(PLEN)-C (Q6/15) provides the return liaison noting that in-band or out-of-band control has not yet been determined; it informs SG11 of the current work status. TD-005(WP2/15) from SG12 provides information on the Subjective Performance on Tandem Encoding. COM12-69© (http://www.itu.int/itudoc/itu-t/com12/contr/069.html, password required) was attached; it provides performance information on a significant number of coding conditions including tandeming and interworking with a variety of codecs, including ITU (except G.723.1) and regional standard cellular codecs. SG12 also notes G.107 which may be helpful to predict

28 Vol. 10.8 Copyright © CSR 1999 August-B 1999 COMMUNICATIONS STANDARDS REVIEW subjective opinion for a range of network configurations. TD-047(PLEN)-D from Q6/15 thanks them for the information. TD-006(WP2/15) from SG13 notes the Approval of Rec. I.380, IP data communications service - IP packet transfer and availability performance parameters, February, 1999. This Recommendation includes a performance model for IP connectionless service. It includes definitions for mean IP packet transfer delay, IP packet error ratio, IP packet loss ratio, spurious IP delay variation and IP flow and throughput. They now plan to select quantitative performance parameters to recommend for IP networks. Since Q6/15 is not in the position to specify any performance requirement on IP-CME, the response to this liaison came from Q21/15. TD-010(WP2/15) (SG8) is a liaison on T.30 extended negotiation procedure (ENP). The potential need of study on ENP was recognized, however the draft ENP for inclusion in T.30 was not approved by SG8. TD-047(PLEN)-G , the response, notes that initial investigations showed potential problems with facsimile transmission over fax remod/demod functions contained in DCME, when using the proposed ENP. TD-016(WP2/15) (SG16) supports the idea of using a 64 kbit/s clear channel instead of the 40 kbit/s coded channel to convey higher bit rate modem signals. TD-047(PLEN)-H responds, thanking them for their offer of collaboration in the study of assigning higher bit-rate VBD (voice band data) signals to 64 kbit/s transparent channel. Q6/15 also requested information from the Administrations on the percentage of total VBD signals, and higher bit-rate VBD signals if possible, in the total GSTN traffic carried over DCME. TD-017(WP2/15) (Q19/16) reports on Q19/16’s progress on voice compression issues: Annex I G.728 (frame erasure concealment) was Approved, corrigendum to Annex H G.728 (lower bit rate extension) was Approved and Annex J G.728 (40 kbit/s extension) was Determined. D.607 (Mitsubishi) provides additional information on Annex J of G.728; it notes that the draft text (SG16 TD-067(PLEN) ) was Determined with some conditions (see CSR Vol. 10.6 for details) and proposes amendments. TD-047(PLEN)-I provides the response. TD-047(PLEN)-J is a liaison from Q6/15 to SG12 providing updated and corrective information to G.114 (One-way transmission time): Transmission or processing system Contrib. to one-way trans. time G.763 DCME (per pair) for speech, VBD, fax (not remod/demod) 30 ms G.767 DCME (per pair) for speech, VBD, fax (not remod/demod) 30 ms G.766 DCME (in conjunction with G.763 or G.767) per pair - for 200 ms fax remod/demod Q6/15 also notes in the liaison that the figure contents of Figures B.2/G.114 and B.3/G.114 are switched.

FUTURE WORK Future studies in next study period were discussed. It was agreed to continue the work of Q6/15 with appropriate modifications to coordinate the tasks with other Questions in WP2/15. It was agreed to advance the work more specifically on the signal processing for Speech/Fax/VBD and Signal Classification. The first text of the Question for next study period was drafted. QUESTION 7, WP2/15 - N ETWORK ECHO CONTROL AND INTERACTION OF ECHO CONTROLLERS AND NETWORK EQUIPMENT The Q7/15 Rapporteur is Y. Tao (Lucent, USA). The main objectives of the meeting were to Approve G.169, Automatic Level Control Devices, and to advance the study on G.168 (2000), Digital network echo cancellers. TD-015(WP2/15) contains the meeting report of the interim meeting in San Francisco, in February 1999. Two interim meetings are proposed.

G.169, AUTOMATIC LEVEL CONTROL DEVICES TD-015(PLEN) contains editorial changes made to G.169 at the San Francisco interim meeting. D.506 (BT) proposes an editorial note to G.169 Section 7.5.2, Tests to confirm satisfactory VBD and fax performance when an ALC device is not disabled by 2100 Hz. The note for designers of fully-automated G.169 test equipment suggests that the requirement to follow all T.30 procedures may be relaxed, but the principle of comparing fax transmission performance with and without the ALC device must remain the basis of the test. After the changes were incorporated, G.169 was Approved as COM15 R29© plus TD-015R1(PLEN) .

G.168 (2000), DIGITAL NETWORK ECHO CANCELERS G.168 (2000) is an update of G.168 approved April, 1997. G.168 (2000) is applicable to the design of echo cancellers using digital techniques, and intended for use in circuits where the delay exceeds the limits specified by G.114 and G.131 (Control of talker echo). Implementations of G.168 will be compatible with implementations of G.165 (echo cancellers) and G.164 (echo suppressors). TD-002(WP2/15) is a liaison from SG8 identifying four issue which may relate to the testing of echo cancellers for performance (including cancellation and rate of convergence) with fax modems. A reply liaison TD-047(PLEN)-B indicates that Q7/15 will study adding or modifying test 10 (FAX test) to include the various aspects of fax pointed out. Currently the simulated sequence does not include JM/CM signals of V.8. TD-003(WP2/15) is a liaison from SG8 pointing to a field problem that was experienced when using V.34 half-duplex modems in which the echo cancellers were not disabled (using ANSam without phase reversals in V.8). TD-003(WP2/15) suggests the cause for this failure is due to the network cancellers training upon the double-talk of the CM portion of V.8. The effect is to suppress 1650 Hz and hence corrupt the communications. TD-031(GEN) from Q4/16 also requests Q7/15 look into this issue. TD-009(WP2/15) from SG8 proposes that Recommendation V.34 be modified to require disabling of echo cancellers for V.34 half duplex modems by sending ANSam with phase reversals. (Technical editor’s note: Q4/16 did agree on an informative note to V.8 on this issue. See CSR Vol. 10.6.) A discussion was held with representatives from SG8 who were familiar with this issue, and D.152© from the March meeting of Q1/8 was reviewed (see CSR Vol. 10.5). A reply liaison was drafted indicating that Q7/15 will study this issue and keep SG8 informed of the results. Several theories on the cause of the problem were discussed, but no conclusions were reached. Members were requested to look for the cause of the problem. A. Pugh (Panasonic) will be the contact from SG8 on this issue. The UK expressed concern that Recommendation G.168 (2000) is being Determined before the issues regarding V.34 fax described in TD-003(WP2/15) have been fully investigated. Not wishing to hold up Determination of a Recommendation that in all other respects is a significant improvement over the current version, the UK agreed that the issues with V.34 fax be investigated during interim meetings and a suitable test (if appropriate) be developed to fix these problems. This test should be included in the Recommendation before Decision at the next meeting of SG15 in April, 2000. G.168 (2000) Draft 5R1 (WD7-4©) with the changes from the San Francisco meeting was reviewed and the contents were agreed. COM15-146© and WD7-6 (Nortel) discuss the proposed Appendix II to G.168 (2000) on echo path measurement methods and their characteristics. With the agreed changes, this is included as Appendix II to G.168 (2000). D.504© (Lucent) describes a method to run the double talk tests 3A and 3B without inhibiting the adaptation. With the agreed modifications, this will be added as Appendix I.8.4, and the current Appendix I.8.4 will be moved to I.8.5. D.522 (Nortel) proposes changes to Annex D to clarify the generation of a digital echo path g(k) for the testing of echo cancellers. This was agreed.

D.526© (Tellabs Oy) proposes six editorial changes and was accepted. D.635© (Tellabs Oy) proposes 18 editorial changes and was agreed with modifications. D.552 (Deutsche Telekom AG) proposes editorial changes and changes to test 2C (convergence test with background noise). The test was modified and split into three sub-tests: (a) Convergence test with NLP (non-linear processor) enabled, (b) Steady state cancellation test with NLP disabled, and (c) Convergence test with NLP disabled (for further study). The text of the tests as modified was agreed and added to G.168 (2000). D.636©, D.637©, and D.638© all from Tellabs Oy are proposals to split G.168 (2000) into three Recommendations respectively: • G.CDNEC.0, on echo canceller equipment specifications • G.CDNEC.1 on test methods • G.CDNEC.2 on guidelines. This was brought up as input for the next study period. G.168 test 2A (convergence test with NLP enabled) and 2B (convergence test with NLP disabled) requirements for starting with random H-register states were agreed. The following tests were agreed to be for study in the next study period: Test 2c – part 3 on convergence test in presence of background noise with NLP disabled Test 10c – Part 3 of FAX test Test 11 – Tandem echo canceller test Test 13 – Performance with ITU-T low bit rate coders in echo path Test 15 – PCM Offset test With the above changes, Q7/15 agreed to recommend the Determination of G.168 (2000). The ITU-T patent policy was noted and no issues were raised. G.168 (2000) was Determined by SG15 as TD-44(PLEN)©. QUESTION 8, WP2/15 - SPEECH, VOICE-BAND DATA AND AUDIO TRANSMISSION IN ATM/B-ISDN S YSTEMS The Q8/15 Rapporteur is H. Kullmann (Deutsche Telekom, Germany). The Recommendation I.741, Interworking and Interconnection between ATM and switched telephone networks for the transmission of Speech, Voice Band Data and Audio Signals was approved under resolution 1 as COM15-R29©, November 1998, plus TD-018R1(PLEN) . I.741 is available to ITU TIES subscribers at http://ties.itu.int/u/tsag15/sg15/wp2/stable_text/I741/ (password required). TD-007(WP 2/15) from SG13 requests information on I.741, particularly ATM performance requirements as they relate to network-based signal processing equipment. In a liaison response to SG12 and 13, TD-047(PLEN)-F Q6/15 and Q8/15 note that the information in I.741 is general and meant as guidelines only. Considering that SG12 has responsibilities for end-to-end transmission performance including aspects such as the effect of ATM performance on the subjective performance, SG12 should confirm that existing I.356 standards meet voice performance standards when using I.741 interworking. TD-008(WP2/15)© provides the DTR ballot ISO/IEC JTC1/SC6N 11136, List of standard data link layer protocols that utilize high-level data link control (HDLC) classes of procedures and list of standardized XID format identifiers and private parameter identification values. Its purpose is to inform Q6/15 and Q8/15 about Data Link Layer protocols using HDLC classes of procedures. TD-018R1(PLEN) contains editorial corrections to Draft Recommendation I.741 relative to the version in COM15-R29©, November, 1998. During the Q8/15 meeting, proposals for the organization of WP2/15 and Q8/15 including the study items for I.741 were discussed for the 2001 – 2004 ITU-T Study Period. Studies on I.741 continue to evolve in response to the definition of new transport network applications and improved definition of existing transport network applications. Table 2 lists on going study items for I.741.

Item Issues Priority ATM-PSTN/MOBILE - Other interconnection schemes 1 Interconnection and Interworking - Non-compressed voice 1 - How the ATM transfer capabilities would map to the PSTN (I.580) 1 - Switching in ATM network 2 - Switching in PSTN network 2 - Switching of PCM voice, compressed voice, and wideband voice 2 Network Interconnection over - More details are needed in general 1 ATM New core items - ATM Adaptation Layers to use 1 - Coding schemes: PCM voice 1 Compressed voice 1 Wideband voice 3 - Capability exchange 1 - Bit mapping in ATM cells, especially of low bitrate coders 1 - Silence suppression 1 Cell fill - Cell fill strategies depending on the adaptation layer used 1 - Octets in a cell should be from one or more than one voice channels 1 - Strategy definition for international networks 1 Cell loss and recovery mechanism - Impact on voice quality depending on the coding scheme 1 - What mechanisms to use 1 - sequencing (sequence number regarding AAL Type 2) 1 Jitter - More information from Q18/13 on synchronization 2 - Cell delay variation impact on voice and description of cell delay variation aspects 1 Transcoding & Gateway - Effect of other voice coding schemes 2 Functions - Capability exchange 1 - Signaling to be used in both sides of the gateways 1 - Voiceband data aspects 1 - Facsimile Terminal Aspects 1 Echo Cancellation - Account for packetization delay 1 - Effect of cell loss in echo cancellers 1 - Where to deploy echo cancellers 1 - How to cascade echo cancellers 1 Congestion and Flow Control - Selection of the appropriate transfer capability (I.371) 1 Other details for PSTN/ATM - Interface to satellite systems 1 interworking - Interface to cellular networks 2 Timing recovery mechanisms - Aspects of using time stamp and adaptive timing recovery (I.363.1) 1 Multipoint Connection Types - Point-to-point connection (uni- or bi-directional), 1 - Point-to-multipoint connection (uni- directional), 2 - Point-to-multipoint connection (bi-directional), 1 - Multipoint-to-point connection (uni-directional), 3 - Multipoint-to-point connection (uni-directional) 3

Priority: 1. Items absolutely necessary to be included in the text of the recommendation before it can be considered stable enough for Determination 2. Items that need to be defined which may be left for further study when of the Determination of the recommendation 3. Items that would be considered should contributions be received. If no contributions are received, it will not be considered as “further study are required” Table 2. On Going Study items for I.741.

QUESTION 21, WP2/15 - SIGNAL PROCESSING ASPECTS OF NETWORKS OPTIMIZED FOR INTERNET PROTOCOL The Question 21/15 Rapporteur is J. Skene (Tellabs, Finland). The main objective was to advance the study of G.TIGIN, Transport Network Equipment for Interconnecting GSTN and IP Networks. TD-018(WP2/15) is the report of the previous Q21/15 meeting in San Francisco, February 1999. TD-011(PLEN) (D. Sparrell, EDH chair) describes Electronic Document Handling) EDH progress for SG15, and reports to the TSAG on the innovative methods for managing documents developed by Q4/15. The Q21/15 Rapporteur indicated that he would use these methods for the next meeting if possible. Working methods for the Question were discussed. The Rapporteur indicated that interim work will be conducted via a web-based technology provided by the ITU IT department, called WebBoard. This is a discussion group system that allows participants to contribute to specific area of work carried out by Q21. To sign on to the board, it is first necessary to have a user ID and password. Delegates interested in subscribing to this board should send a request via email to the Rapporteur ([email protected]). The URL of the webboard is http://wwwp.itu.int:8080/~itu-t/. It was agreed that the Rapporteur will add the Q21 mailing list itself to the webboard user list, so that all Q21 list members will receive email notification of new messages.

INCOMING LIAISONS TD-023(WP2/15) (Rapporteur Q9/11) indicates that work is commencing on echo control logic for Voice Over Internet Protocol (VoIP) networks (IP or ATM based). SG11 has agreed to change Q.115 to provide echo control logic for IP and ATM networks. TD-023(WP2/15) also notes that the current draft of G.177 (Transmission planning for voiceband services over hybrid Internet/PSTN connections) addresses delay and echo control for voice calls over IP networks. It was noted that this work will affect the Media Gateway Controller more than TIGIN equipment. TD-022(WP2/15)© (ETSI TIPHON) provides TIPHON network architecture and reference configurations Phase II: scenario 1 + scenario 2, TS 101 313 V0.4.2. This ETSI document describes network architecture and reference configurations being used in their work. This is relevant to the work being done in Q21/15 and was used during the meeting as a reference. It was noted that Q21/15 uses the decomposed gateway model described here. TD-011(GEN) is a liaison from SG12, describing the work they are doing on the transmission performance impact of introducing IP-based technology into the PSTN. It was noted that draft Recommendation G.177 has relevance for Q21/15’s work; Q21/15 will follow the progress of this work. TD-012(GEN) and TD-013(GEN) are liaisons from SG13, describing work on GII and IP projects, respectively. TD-012(GEN) announces that SG13 will convene an IP experts meeting in September. A liaison was sent to the source of TD-12(GEN) , indicating that several Q21/15 delegates are interested in attending this meeting. TD-014(GEN) is a liaison from SG13 requesting information on work relevant to IP-related work performed in the IETF. It was noted that IETF working groups relevant to Q21/15 include the Media Gateway Control Protocol (Megaco) and Signaling Transport (SIGTRAN) groups within the Transport Area. Information was sent to SG15 management indicating these relationships, as part of an outgoing liaison. TD-034(GEN) (Q25/4, responsible for the TMN framework) provides information on integrated remote management work in progress as a response to a liaison from SG13 on the ITU-T IP project. TD-006(WP2/15) (SG13) gives information on a new Recommendation, I.380, Internet protocol data communications service - IP packet transfer and availability performance parameters. This Recommendation will be studied to determine its relevance to Q21/15’s work. A liaison statement

was sent to WP4/13, informing them of the work being done in Q21/15, and requesting guidance on the performance requirements of TIGIN gateways. G.TIGIN WD21-5 is the current work plan from the Rapporteur. It provides a list of issues that Q21/15 is addressing. New items will be added addressing tandem free operation, availability and the physical integration of a TIGIN gateway with an MGC (media gateway controller). ITU TIES subscribers may find the v3 draft (output of this meeting) at http://ties.itu.int/u/tsg15/sg15/wp2/stable_text/gtigin/gtiginv3 (password required). TD-27(GEN) from the rapporteur provides discussion points on G.TIGIN. It was agreed that echo control logic would be performed within the MGC, and not within a TIGIN gateway. It was agreed that any discussion of echo control logic in G.TIGIN would refer to Q.115 (Logic for the control of echo control devices), as updated by Q9/11 for inclusion of echo control logic for IP networks. TD-29(GEN) from the Rapporteur provides the scope of G.TIGIN, Section 1.1: This Recommendation covers the requirements of equipment that interconnects GSTN networks and networks optimized for Internet Protocol (IP). Such equipment is referred to in this document as a TIGIN gateway. The Recommendation describes functionality, transport interfaces, transcoding protocols, signaling interfaces, operation, configuration and management of these devices. While such TIGIN gateways may support multimedia traffic, this recommendation covers only voice and voice band data traffic requirements. Support of other media such as digital data and video are left for further study. In this sense, a TIGIN gateway is a subset of the Media Gateway. This Recommendation does not define any new protocols or architecture, but rather refers to existing protocols and architectures. It also does not specify a level of performance as this will be covered by other Recommendations referenced this document. TD-28(GEN) is the G.TIGIN draft outline, revision 2. D.511 (M. Noah, ADC telecommunications) contains requirements and suggestions for Recommendation G.TIGIN, including a suggested breakdown of items within the Recommendation, updated references, and specific suggestions for text for several sections. Multiple changes were made to the G.TIGIN draft, TD-28(GEN) , as a result of this contribution. TD-030(GEN) (Rapporteur) is sections 1.2, 1.3 and 1.4 of G.TIGIN draft Recommendation, describing References, Terms and Definitions, and Abbreviations. M. Noah (ADC Telecommunications) agreed to be editor of these sections. Figure 2.1 was changed as follows: • Text on TDM and IP interfaces was removed • Boxes on echo canceller and voice features were combined into a box labeled signal processing • A box labeled signaling gateway was added, with the note that it is optional • References to PCC protocol, TMN, SNMP were removed • LAN was changed to Network Interface It was agreed to add text to section 2 describing the fact that a TIGIN gateway may need to support some signaling gateway functions when TDM channel associated signaling is used. In section 3, figure 3.1 was changed as follows: • A new line labeled “Facility Associate Signaling” was added between the GSTN cloud and G.TIGIN • The term “Media Gateway” will be changed to “TIGIN Gateway” (here and throughout the document) • “TDM Transport Interface” and associated recommendations with be changed to “TDM Bearer Interface” • “IP Transport Interface” and associated recommendations will be changed to “IP Bearer Interface”

• A new line connection G.TIGIN to MGC will be added, labeled “signaling over IP” • A label “signaling over IP” will be added to the line connecting SC to MGC • The SC box will be moved to the left of the MGC box, indicating that signaling entering this box from the outside originates with the TDM network It was stated that if a single network management/call control interface is used and large volumes of network management traffic are present, then call control bandwidth would suffer. It was therefore agreed to add a new section on network interface performance requirements. A defined list of IP bearer interfaces to be supported, including a layered description of these (provided by M. Holdrege, Ascend), follows: • Layer 3 IP • Layer 2 PPP, FR, ATM • Layer 1 G.704, G.707, G.703, G.957 • Handling of IP over PPP to be defined as in IETF RFC 1661 • Handling of IP over Frame Relay to be defined as in IETF RFC 2427 • Handling of IP over ATM to be defined as in IETF RFC 1483 or MPLS (contribution on IP/ATM to come) • Handling of IP over SDH to be defined as in IETF RFC xxxx (approved, but number not yet assigned. Text will be included in section 3.2, stating that at least one of the stated interfaces needs to be supported. D. Parola (Lucent) agreed to provide a list of GSTN TDM bearer interfaces to be included. In Section 3.3, it was agreed to break section 3.3.1 up into two subsections, 3.3.1.1, Upper layers for PCC (per call control), and 3.3.1.2, Lower layers for PCC. Upper layer will be as defined in draft Recommendation H.GCP (to be Determined in September 1999), and the lower layers will be as defined in section 3.1, and will include reference to common LAN interfaces. There was discussion on how or if a TIGIN gateway would determine or set packet size, and also on extracting signaling from TDM trunks and mapping this into signaling messages for a Signaling Gateway. TD-047(PLEN) is the liaison sent to Q13/16 requesting guidance. A new, optional, section 3.4 will be added, tentatively titled TDM Signaling Interface. This section will describe the method by which the TIGIN gateway extracts and passes on facility associated signaling (FAS), if required. It was noted that a TIGIN gateway must include a Signaling Gateway if it is to support FAS. Subsections on FAS methods were agreed as follows, for placeholder purposes. Contributions on each item (below), including the specific method in which each signaling method is to be supported and the correct method of referencing the subject standards documents, are requested. It is noted that if a TIGIN gateway makes use solely of SS7 signaling, then compliance with this section is not required. Subsections include: • SS7 Facility Associated Signaling • Q.931 • R1 – Q.2 • R2 – Q.400 • Placeholder for Q.SIG (ECMA) • Placeholder for V 5.2 (G.965) • Placeholder for GR-303 (Telcordia) • Channel Associated as per G.704 In section 4.1, it was agreed to change the title “voice features” to “signal processing features.” This section will be broken into two sections, one containing mandatory items, and one optional items. A mandatory voice coder will be G.711. It was agreed that a section on reliability and performance would be added, covering such items as redundancy, safety, reliability, etc. Reference will be made to existing Recommendations covering international switching equipment where relevant.

SG15 WP1 & 2 MEETING ROSTER, JUNE 21 – JULY 2, 1999, GENEVA, SWITZERLAND Peter Wery (Canada) SG15 Chair Gastone Bonaventura (Italy) SG15 Vice-Chair Makoto Yamashita (Japan) SG15 Vice-Chair Andrew Nunn (UK) WP1/15 Chair Duncan Sparrell (USA) WP2/15 Chair

Belgium Frank Van Der Putten Belgium Alcatel Bell Geert De Vries Belgium Alcatel Bell Ludwig Pauwels Belgium Alcatel Bell Thierry Pollet Belgium Alcatel Bell Peter Reusens Belgium Alcatel Bell Danny Van Bruyssel Canada Andy Weirich Canada Peter Wery Canada Mitel Gordon Reesor Canada Mitel Silvana Rodrigues Canada Newbridge Networks Feng Tian Canada Nortel Networks Dominique Ho China Yue Chen China Yunzhi Chen China Ping Gong China Yida He China Qian Mao China Shunyao Ren China Junhua Wang China Leping Wei China Xiaofeng Wu China Yongming Xu China Chengliang Zhang China Zhiyi Zhang Denmark Tele Danmar Otto Kimer Finland Eino Jauhiainen Finland Helsinki Telephone Co Seppo Törmälä Finland Helsinki Telephone Co. Juha Kauppi Finland Nokia Paulus Capelan Finland Nokia Tommi Koistinen Finland Nokia Lippo Rantanen Finland Nokia Jouko Törmänen Finland Tellabs Oy Charles Balogh Finland Tellabs Oy Maurice Givens Finland Tellabs Oy Jerry Skene Finland Tellabs Oy Janne Väänänen France Daniel Battu France Michel Bonnifait France Lucien Bourgeat France Lionel Guingo France Gilles Joncour France Ascend Communications Premea Matt Holdrege France France Telecom Tryeb Ben Meriem France France Telecom Alvaro De Diego France France Telecom Valerie Turbin France IBMEurope Sedat Oelcer Germany Reinhold Feigel Germany Hans L. Koffler Germany Harald Kullmann Germany Gunther Zedler Germany Alcatel SEL Siegfried Schmoll

Germany Deutsche Telekom Ralf-Rainer Damm Germany Deutsche Telekom Andreas Templin Germany Lucent Technologies Network Chris Jolly Germany Siemens Diek Daecke Germany Siemens Franz Dielacher Germany Siemens Ulrich Fiedler Germany Siemens Josef Forster Germany Siemens Hagen Henniger Germany Siemens Neal King Germany Wandel und Goltermann Wolfgang Miller Greece OTE Sofia Dratatou Greece OTE Vassilios Kanellopoulos Greece OTE Elias Yannopoulos Hungary MATÁV Hungarian Telecomm Laszlo Barna India Surinder Kumar Malhotra Israel Ishai Ilani Israel Ken Krechmer Israel Meir Leshem Israel Oren Marmur Israel Aharon Segev Israel Moshe Topman Israel Ram Verbin Italy Sergio Cascelli Italy Roberto Flaiani Italy CSELT Andrea Allasia Italy CSELT Marco De Bortoli Italy CSELT Andrea Mazzotta Italy CSELT Luca Messina Italy Marconi Sabrina Lettere Italy STMicroelectronics Gerard Fagere Italy STMicroelectronics Sabina Fanfoni Italy STMicroelectronics Simone Mazzoni Italy Telecom Italia Gastone Bonaventura Japan Norihiro Fukuda Japan Toshiro Kato Japan Yoichi Maeda Japan DDI Osamu Tsuhako Japan Fujitsu Yutaka Awata Japan Fujitsu Fumihiko Saito Japan Fujitsu Haruo Yamashita Japan Hitachi Tohru Kazawa Japan Japan Telecom Yoshihiro Hayata Japan Japan Telecom Masahiro Soma Japan KDD Yoshinori Namihira Japan KDD Toshikane Oda Japan KDD Yasuyuki Watanabe Japan KDD Hideaki Yamada Japan Matsushita Electric Industrial Stephen Palm Japan Mitsubishi Electric Wataru Matsumoto Japan Mitsubishi Electric Yushi Naito Japan NEC Hiroyuki Furuno Japan NEC Yuichi Koyama Japan NEC Genichiro Sekine Japan NTT Shinichi Aoyagi Japan NTT Koji Kikushima Japan NTT Kazuhiro Oda Japan NTT Masaharu Ohashi Japan NTT Makoto Yamashita

Japan OKI Electric Industr Katsuhiro Ishimura Japan OKI Electric Industry Yoshihiro Kondo Japan OKI Electric Industry Akihiro Takahashi Japan Sumitomo Electric Industries Masami Ueda Japan Toshiba Kyosuke Dobashi Japan Toshiba Hiroshi Fukinuki Japan Toshiba Yasumasa Kikunaga Korea Kanghee Yoo Korea Korea Telecom Suncheol Gweon Mexico Lucio Adame Morocco Itissalat Al Maghrib Hafid Charki Netherlands Lucent Technologies Nederland Martin Grim Norway Jarle Kiil Norway Björn Nordset Poland Marian Marciniak Russian Federation Viacheslav Biryukov Russian Federation Dmitri Cherkesov Russian Federation Dmitri Masurenko Russian Federation Igor Movtchan Russian Federation Stella Piterskikh Saudi Arabia S.TC Abdulrahman Al Rijraji Saudi Arabia S.TC Abdulaziz Alkesayer Saudi Arabia S.TC Osama Arab Spain Enrique Berrojalvis Spain Telefónica Jose Luis Novoa Lozano Sweden Anders Höglund Sweden L.M. Ericsson Jan Boström Sweden L.M. Ericsson Albin Johansson Sweden L.M. Ericsson Tönu Trump Sweden Telia Mikael Isaksson Sweden Telia Niklas Johansson Switzerland Hassane Makki Switzerland Swisscom Philippe Repond Syrian Arab Republic Nabil Kisrawi UK Chris Firth UK Andrew Nunn UK Mark Robinson UK BT Nigel Ballington UK BT Kevin Foster UK BT Robert Reeves UK BT George Skorkowski UK BT David Thorne UK Lucent Technologies John Magill UK Marconi Communications Ghani Abbas UK Nortel Network Leslie Humphrey UK Panasonic Standards Europe Alan Pugh UK Tektronix UK Mark Lum Ukraine Mykola Biryukov Ukraine Anatoly Glushkovskyy Ukraine Viktor Katok USA Elaine Baskin USA Steven Blackwell USA John Chen USA John Cioffi USA Gary Fereno USA Juan Garza USA Richard Goodson USA Thanos Kipreos

USA James E. Matthews USA John McDonongh USA Matthew Noah USA Duncan Sparrell USA Benson Wang USA Guy Wells USA 3Com Joseph Mueller USA 3Com Richard Stuart USA Advanced Micro Devices Terry Cole USA AltoCom Arthur Carlson USA Ameritech Services Tom Starr USA AT&T Deborah Brungard USA AT&T Gonzalo A. Mariano USA Aware Marcos Tzannes USA Centillium Technolog Syed Abbas USA CIENA Corporation Jerry Shrimpton USA Cisco Systen Amir Hindie USA COMPAQ Rabah Hamdi USA Conexant Systems Keith T. Chu USA Conexant Systems George Eisler USA Conexant Systems William Jones USA Ditech Thomas Oshedari USA Excess Bandwidth Corp Christopher Hansen USA Fujitsu Network Comm. Emir Catovic USA General Instrument Sabit H. Say USA Globalstar LP Henry Meyerhoff USA GlobeSpan Technologies Massimo Sobara USA GTE BD&I Gary McAninch USA Intel Christopher Hansen USA Intel Barry O’Mahony USA Lucent Technologies John Eaves USA Lucent Technologies Song Jiang USA Lucent Technologies Kam Lam USA Lucent Technologies Vladimir Oksman USA Lucent Technologies Dario Parola USA Lucent Technologies Avinoam Perry USA Lucent Technologies Mark Simkins USA Lucent Technologies Ying T. Tao USA MCI WorldCom Robert Born USA MCI WorldCom Daryl C. Tannis USA MediaOne James Dahl USA Motorola Info Systems Les Brown USA Motorola Info Systems Bernard Dugerdil USA NEC US Samir Kapoor USA NEC USA Donovan Nak USA Nortel Network (USA) Mike Ahdieh USA Paradyne Corporation R.K. Smith USA PC-Tel Yuri Goldstein USA PC-Tel Khashayar Mirfakhraei USA RSA Communication Richard Simeon USA SBC Technology Resources John Roquet USA Texas Instruments James Carlo USA Texas Instruments Jacky Chow Venezuela CANTV Antonio Castaldi Felizola ITU William Kirsch ITU-TSB Paolo Rosa

REPORT OF ETSI TIPHON MEETING #14 JULY 19 – 23, 1999, AMSTERDAM, HOLLAND H. Schink (Siemens) is the TIPHON chair. TD-023 is the meeting report. TD-005, The TIPHON 13 meeting report from Bangkok (G. Meyer, Siemens and TIPHON Secretary), was reviewed and approved by the meeting. An update, TD-005r1, will be provided as a permanent document. AT&T Netherlands hosted this meeting which was a paperless meeting, i.e., no documents were printed. AT&T provided Internet connectivity with a bitrate of 128 kbit/s. The local networking capabilities included wireless LAN access; this enhanced the efficiency of the meeting and allowed the delegates to update their database throughout the meeting. It was recommended to continue this support for future TIPHON meetings. The ETSI Board endorsed the appointment of H. Schink (Siemens AG) as TIPHON chair for a period of two years.

IPR (INTELLECTUAL PROPERTY RIGHTS) The Chair reminded all participants of ETSI’s IPR policy and invited the attendees to announce IPRs of relevance to TIPHON. No announcements were received.

REVIEW OF ACTIVITIES The action list from the TIPHON 12 report was scanned for open items. Most action items have been completed and reported. The updated list is given in TD-023 clause 12, Decisions and To Do List. Special Task Force (STF) TD-076 (S. Cadzow, STF leader) is the Interim Report from STF114 Between TIPHON 13 (Bangkok) and TIPHON 14 (Amsterdam). This report provides the text of the formal STF114 progress report for ETSI. It was approved. Marketing Activities S. Thomas (Vice Chair) was not presentc. TIPHON was represented at the VON Europe conference by R. Zwart (AT&T) and A. Dilber (AT&T). A presentation was given to JTC1 by H. Schink (Siemens AG). ITU-T SG16 M. Buckley (Lucent) gave a short overview on the work relating to MGCP and H.248 (former H.GCP). He pointed out that H.248 will be a joint Recommendation from ITU-T and IETF. The work is split with the IETF focusing on requirements and the ITU-T drafting the H.248 document. The TIPHON requirements have been addressed in this work. ITU-T SG 15 M. Holdrege (Ascend/Lucent) reported that Q21/15 is discussing specifications for VoIP equipment, especially Media Gateways. The work is driven mainly by US carriers. The next meeting will be in January in Montevideo, Uruguay. 3GPP Since China has joined the project, 3GPP now consists of six partners; Canada is acting as an observer. From next year on, the work will go towards “mobile IP.” The exact focus of this work has yet to be discussed. The main contact person for TIPHON will be J. Fenn who agreed to work on a cooperation strategy jointly with L. Spergel (Lucent). TC STQ (Speech Transmission Quality) TC STQ held a workshop in Sophia Antipolis in June, 1999. One of the most interesting presentations was from KPN about user acceptance of different QoS and speech quality levels. Below a certain quality threshold, users will try VoIP but will never use it again after a bad experience with this technology. Although the material was available, the speaker from KPN was not available for this meeting and will be invited to TIPHON 15.

IETF H. Schink (Siemens and TIPHON Chair) reported on the issue of ICANN (Internet Corporation for Assigned Names and Numbers) and the PSO (protocol support organization). He reported about the discussions in the IETF/Oslo on the positioning of ETSI and mentioned that the final result was that the IETF accepts ETSI as a signatory of the PSO MoU. This is clearly an indication of the support for the work of TIPHON and will give TIPHON better working conditions for the future. M. Holdrege (Lucent) reported about the decision of the Megaco design team towards text encoding vs. binary encoding. Media Gateway Controllers must support “ipsec,” but this is not clear for Media Gateways. The use of TCP will be required for Media Gateway Controllers besides the use of UDP + timers and MDTP (Multi-network Datagram Transmission Protocol). IMTC TIPHON and IMTC organized a joint InterOp event in Sophia Antipolis in June. MSF (Multiservice Switching Forum) TD-122, Multiservice Switching Forum; A Forum Overview (F. Renon, MSF/CSELT), was a slide presentation providing insight into the charter and work area of MSF; it started a more detailed discussion on areas of cooperation or work split. The MSF charter is to develop and promote implementation agreements for intra-switching system protocols and interfaces which enable an open architecture for multiservice switching systems which support ATM, Frame Relay, IP, Voice and Video services. A cooperation was endorsed in principle; the meeting agreed that TIPHON and MSF are working in very related technical areas and careful, open cooperation is required in the interest of the industry. TD-116, Liaison to MSF (H. Schink, TIPHON and F. Renon, MSF/CSELT), requests an endorsement of the outlined liaison strategy and proposes more detailed areas of cooperation including MSF providing input to TIPHON on IN, e.g., in the areas of usage of IN in a distributed environment and further enhancements of IN. As a medium term goal, a cooperation agreement should be achieved and published as permanent document. A first feedback from MSF gives a positive response. MSF will try to submit material into TIPHON 15 from their August meeting in Montreal. Presentation of InterOp 3 S. Cadzow (ETSI STF 114) pointed out that several contributions to WG6 deal with InterOp. An explicit feedback loop was established to amend the specifications according to the findings of the InterOp events. He also asked whether companies would be interested in remote testing before InterOp 4. Several companies indicated interest. TTC/ETSI Cooperation The discussions from Bangkok on cooperation between ETSI TIPHON and TTC (Japanese standardization committee) continued in Amsterdam. The representatives of TTC, K. Nakashima, N. Oota and Y. Saito, expressed TTC’s desire to cooperate with ETSI and, in particular, with TIPHON. TTC has performed an analysis of the future activities of TTC in the IP related area, which determined the creation of a new TC (technical committee). The overall goal is to accelerate to processes in ITU-T and TTC in the IP-related area. The chair of this new TC will be invited to the next meeting of TIPHON. It was agreed to create a cooperation agreement between TTC and ETSI. L. Vreck will contact the ETSI relations officer to initiate the drafting of the cooperation agreement, based on the cooperation agreement between ETSI and IMTC, and specifically tailored for TTC. The goal is to have the completed agreement signed prior to the TIPHON 15 meeting. TIPHON, and possibly other TBs (technical bodies) as well as the respective TTC bodies, will be identified in an Annex to allow for a flexible updating of the agreement. The agreement shall allow TTC to send an observer to TIPHON meetings and vice- versa. As an interim solution, the chair of TIPHON will invite experts from Japan who are not ETSI members to individual meetings.

PRESENTATION OF TDS ALLOCATED TO PLENARY TD-029©, Threat Analysis (S. Cadzow, ETSI STF 114), proposes a new work item (see BoF session on threat analysis, below), which was approved by the meeting. S. Cadzow proposed another new work item on the revision of DTR/TIPHON-00001, the overview document, which

was approved by the meeting. ETSI procedures allow the approval of the revised document in only one step after having first text if this procedure is announced in advance. WORKING GROUP 1, REQUIREMENTS L. Klostermann (Ericsson) is the WG1 chair. TD-006 is the agenda. INTEROPERABILITY TD-046, iNOW! Implementers Guide, Special Interest Group (SIG) of IMTC (L. Moscovici, Vocaltec, SIG Chair), proposes to clarify, correct and complement issues concerning the iNOW! v2 profile. This work includes: • Decide final text for Implementer’s Guide in IMTC ballot • Apply corrections in profile and as contributions to standards (H.323) TD-046 states that the main scope of iNOW! v2 is phone and fax calls across administrative domains with the following specific points of reference: • Gateway to gateway voice: H.323v2 using fast connect. • Fax using T.38. • Gatekeeper to gatekeeper using H.225.0 Annex G. TD-046 does not contain new requirements (see the WG3 and WG6 reports, below). TD-069, iNOW! Standards-Based IP Telephony Interoperability Profile, iNOW! Version 2.0 February 23, 1999 (T. Anderson, G. Freundlich, P. Gerhardt, T. Houghton, A. Literati, S. London, and S. Siegel, Lucent; D. Clowes, OzEmail Interline; E. Hirschman and J. Yu, ITXC Corp.; L. Moscovici, E. Sion and S. Sweet, Vocaltec Communications), addresses: • Gateway to gateway interoperability (brand A to/from brand B) • Gatekeeper to gatekeeper interoperability (brand A to/from brand B) • Gatekeeper to clearinghouse interoperability (brand A and brand B to/from clearinghouse) • Phone to phone service • Fax to fax service The iNOW! Profile does not address: • Gatekeeper to gateway interoperability (brand A gatekeeper to/from brand B gateway) • PC/device to phone service • Roaming service • Clearinghouse cascading, where one clearinghouse originates/redirects traffic to another clearinghouse • SS7 Support TD-069 specifies a discrete set of core functionality within both published and developing IP telephony standards. The goal of publishing the iNOW! Profile is to accelerate true interoperability between Internet Protocol (IP) telephony platforms. The iNOW! material is for information. It was reviewed with the aim of identifying missing requirements in TIPHON. The group went through the list of interoperability requirements contained in TD-069. It was agreed to capture a requirement indicating that disconnect causes shall be transported end-to-end (#5). It was agreed to capture a requirement indicating that an accurate and reliable source of time is required. It was noted that the iNOW! profile supports G.729A as preferred and G.723.1 as second choice. iNOW! does not support the GSM and IS-41 codecs requirements. #13 indicates that a dedicated error code is needed to inform that a call was terminated by the clearing house. It was questioned why this was needed, and whether it is not more interesting to know why a call was stopped, rather than by whom. iNOW! is not TIPHON-compliant in the sense that it focuses on H.225 Annex G (Communications between administrative domains) rather than the TIPHON-developed Open Settlement Protocol (OSP) for Inter-Domain Pricing, Authorization and Usage Exchange (DTS-03004). The iNOW! website is at http://www.inowprofile.com.

NUMBER PORTABILITY

TD-057 (R. Stastny, OeFEG) extends the scope of WI 4006, “Functional Requirements and Architecture for E.164/IP Resolution,” to incorporate not only the resolution of E.164 numbers for

42 Vol. 10.8 Copyright © CSR 1999 August-B 1999 COMMUNICATIONS STANDARDS REVIEW global services, but also the resolution of geographic E.164 numbers for routing and number portability issues. It also requests including E.164/E.164 resolution as a basis for Global Number Portability (GNP). TD-057 was deferred until after the WG4 meeting. During the second WG1 meeting, it was noted that TD-057 had not been discussed in WG4 due to lack of time. R. Stastny indicated he would contribute more information on address resolution scenarios for the next meeting.

ACCESS DOMAIN SUPPORT

TD-096, A Layered Network Architecture for Voice and Multimedia over IP (L. Klostermann, Ericsson), advocates that TIPHON adopt a layered architecture as a principle, and outlines the relevance of this principle for the discussions on QoS and wireless access. TD-096 raises the issue of independence of a service provider from roaming partners and access networks for offering add-ons to the basic H.323 service. A different business background could lead to a different service architecture approach; a roaming partner can have different migration strategies and speeds of migration. Therefore, it was proposed that it should be possible for a service provider to request an access domain to act as a proxy and relay the control signaling via the home/service network. This then gives the operator full freedom to deploy the service architecture that best serves its business, and also enhance it. This requirement was accepted.

UPT

TD-083, UPT on IP Telephony Networks (R. Stastny, OeFEG), is a short report on the current status of discussion in ITU-T SG2 and ETSI NA2 NAR regarding the global code issue. It proposes an alternative approach to the assignment of a new global numbering resource: if individual operators wish to use the code “878” which is currently reserved for UPT, they can approach SG2, however they will be expected to show their alignment with the UPT service description and the criteria specified in ITU-T Recommendation E.164.1 for Global Service Codes. This is the first step taken towards the alignment with the UPT service description. Annexes to TD-083 compare the UPT service description and IP Telephony. TD-083 proposes following an approach where the UPT code “878” is also used for IP Telephony and concludes that IPT is compliant to UPT. It was questioned whether IPT is intended as a requirement or as an argument against the UPT code as a replacement for the global country code. It was decided to defer the discussion and await the outcome of the WG4 discussion. During the second WG1 meeting, it was noted that TD-083 was hardly discussed in WG4, partly due to absence of the contributor to explain his intentions. After looking at the conclusions section, which indicates only numbering range issues, it was decided not to discuss this contribution further.

TD-104, UPT and IP Telephony Networks (K. Hellesvik, Telenor AS), proposes to initiate activities in cooperation between TIPHON and SPAN2 (previously NA2) to define the additional technical requirements to take full advantage of the IP technology not only to support UPT on IP Telephony, but also to make the global and network independent “Personal Mobility” concept of UPT possible.

TD-112, Network Scenarios for Voice and Multimedia over IP (R. Swale, BT), requests that WG1 revise the scenarios identified for the TIPHON project to enable IP network issues to be better addressed in the other working groups. It is aimed at helping further clarify the revision proposals discussed at the TIPHON 14 plenary session. TD-112 raises the issue of interworking with so-called packet cable networks; it does not go in any detail, but there was some general discussion to try to clarify the issue. It became clear that interaction with packet cable networks in principle would not require anything special. In other words, packet cable networks could simply use the TIPHON standard on top of IP. Some cable operator consortia are, however, working on parallel solutions at application level. CableLabs was mentioned as one of such consortia. It was concluded that TD-112 itself was too high a level for further discussions; R. Swale (BT) was invited to provide more information at the next meeting.

REQUIREMENTS TRACING The chair had proposed that WG1 continue activities on requirements tracing, and had done some drafting on the Annex B concerning the status of the work on the requirement in other working groups within TIPHON. There was a significant amount of support for this work; discussion covered the phasing and bundling of the TIPHON deliverables in true, more visible, releases. It was suggested that this could be done by market segment, but it was questioned whether this could result in restricted architectures not suitable for other segments. The present scenarios are insufficient, since it makes a difference whether, e.g., the IP-to-phone transition is NNI or UNI. This is for further consideration. The DTR-01003 (Requirements for Service Interoperability, Scenario 3) already contains some distinction in this area (e.g., national user service, global transit service). Some off-line drafting and discussion took place, and the progress part in the requirements tracing was enhanced in order to distinguish between stage 1 (architecture/protocol requirement), stage 3 (protocol), inclusion in testing program, and inclusion of tutorial material. The table entries will contain, where applicable, references to work items and pointers to sections in the deliverables. The STF will assist in getting this information in place, after which this table can be a good tool for cross-referencing and tracing the progress of the work. The updated table format is included in DTR-01003v011. This version contains the accurate and reliable timing requirement as a sentence rather than a numbered requirement, which is subject to change.

BUNDLING/PHASING After the discussions in WG1, the PMC had some discussions on phasing and bundling of deliverables and work. After some minor changes, the bundling in Table 2 was proposed to the meeting. Phase 1 was completed in 12/98.

Phase 2 Phase 3 Phase 4 before 12/99 before 12/00 Scenario 1-4, inter-domain basic call Mobility and wireless aspects Terminal Aspects with basic features (e.g., CLI) Real time fax/data QoS signaling/firewall control Multimedia Best effort (in controlled environment) More security Basic security More OA&M Basic OA&M Enhanced features, service mechanisms and benchmark services Table 2. Bundling of WG1 Deliverables and Work. One of the intentions of the more visible phasing is to provide guidance for the priority setting in working groups. Interaction with other bodies might also be more focused, when an activity from another body is required in order to offer a complete package. It is not intended to treat the time scales as strict requirements, but rather focus on the packages. Per TIPHON phase, there will be a certain set of DTRs and DTSs which will be documented. For the moment, it was felt that the scope descriptions can be part of the present work items. However, a separate work item could increase visibility. This is for consideration. LIAISON ACTIVITIES TD-087, Service Management (P. Wu, TIPIA), advises WGs 1, 2 and 5 that TIPIA has started to work on Operations, Administration, Maintenance and Provisioning (OAM&P), and provides the first draft of a planned TIPIA deliverable. Requirements have not yet been identified, but TIPIA will inform TIPHON once they are available. It was noticed that it had just been decided to include some OA&M support in TIPHON Phase 2, to be published by the end of this year.

TD-037r1, DTR-04004v0.0.2: Guide to Numbering Options for Public Networks Based on VoIP Technology (ETSI), was sent as a liaison to ETSI WG NA8 (NA and SPS were combined into SPAN in April, 1999) and provides basic guidance on the range of different numbering options within E.164 that may be used for services provided on public networks using TIPHON- compliant technology. TD-027, Response to NA8 Liaison on Charging in IP-based Networks (L. Klostermann, Ericsson and TIPHON WG1 Chair), thanks ETSI WG NA8 for informing WG1 about TR/NA-080301, Parameters and Mechanisms for Charging in IP based Networks. TD-027 informs WG NA8 that TIPHON is presently focusing on accounting and settlements for the IP telephony application. The focus so far has been on interworking between the SCN domains and VoIP domains, where charging and accounting principals of the SCN have been adopted for accounting between SCN and VoIP domains. Accounting can be bilateral or be performed via a clearinghouse/broker. TD- 027 also provides some comments and questions about TR/NA-080301 and suggests that further discussions would be useful, particularly on the issue of accounting and charging at IP level and/or application level. TD-136, SPAN8 to TIPHON (H. Orlamunder, SPAN8), is the liaison response including “Parameters and Mechanisms for Charging in IP Based Networks” draft TR/NA-080301 V1.0.7 (06/99). This includes the SPAN8 responses to the TIPHON liaison (TD-027). SPAN8 suggested a joint meeting with NA8, NA2 and TIPHON, to clarify issues. It was decided not to review the NA8 document in the meeting, but have a look at it before the TIPHON 15 meeting. The next SPAN8 (previously NA8) meeting is September 22-24, so WG1 must respond before that date. The liaison will contain comments on the draft sent by NA8, and a proposal for a joint meeting with WG1. WORKING GROUP 2, ARCHITECTURE J. Vandenameele (Alcatel) is the WG2 chair. TD-007 is the agenda. The major objectives of the meeting were to: • Achieve a stable state of DTS/TIPHON-02003, Network Architecture and Reference Configurations; Phase III Scenarios 1 to 4 (Version 0.2.1) • Create the second draft of DTS/TIPHON-02007, Network Architecture and Reference Configuration for Back-End Services (Version 0.0.0) PROPOSED IMPROVEMENTS TO THE ARCHITECTURAL MODEL It was agreed to hold a drafting session to improve the current architecture reference model, taking into consideration the proposals contained in the contributions to TIPHON 14. TD-071, Proposal for a True Functional Architecture for TIPHON (P. Sijben, Lucent). Considering back end services and the discussion on whether call state lives in the MGC, CA (call agent) or GK, TD-071 proposes the adoption a three-layer (media, call signaling, services) functional architecture; this architecture is considered to be a more functional and abstract architecture than the two current architectures. TD-072 provides an example of such an architecture. TD-072, Functional TIPHON Architecture with Mapping to H.323 (P. Sijben, J. Segers, and M. Buckley, Lucent), proposes the adoption of the revised functional reference, and initiation of a new work item which would: • Investigate a new reference point M between call signaling and service planes • Make an inventory of the information flows needed for new reference point M • Identify existing protocols that are suited for use on this interface and identify where new protocols are needed TD-073, Adding a Third Dimension to the TIPHON Architecture (P. Sijben, Lucent), proposes adding a third dimension to the TIPHON architecture where transport will be placed, adopting this model, and initiating work on the specification of reference points in this area as far as they are relevant for TIPHON services. Examples of certain architectural elements that are evidently necessary but do not quite fit in the existing TIPHON architecture are firewalls, the “borderwall” concept, and reference points for QoS transport issues which need to go to every element in a

network. This proposed third dimension would allow the representation of these additional architectural elements. (See also WG5, below.) TD-074, Comparison Between H.323 Gatekeeper Routed and ISUP Based Direct Routed Scenario 3 Calls Between Decomposed Gateways (B. Van Doorselaer and J. Bouwen, Alcatel), promotes the inclusion of architectures without gatekeepers as TIPHON compliant and concludes that WG2 and WG3 are to work on ISUP-based direct routed call scenario. (See the WG3 report, below.) TD-101, Further Development of TIPHON Functional Architecture (J. Bouwen and B. Van Doorselaer, Alcatel), identifies some flaws of the current architecture, formulates guidelines for a consistent further development, and proposes a solution that reflects more clearly a functional view of the architectural components. It proposes the continued development of the TIPHON Reference Architecture according to the following guidelines: • Earlier defined reference points should be preserved to the maximal extent possible, to ensure continuity of the standardization process. • Names for functional entities that are intuitively linked to physical implementations should be avoided. The term Gatekeeper is best removed from the architecture. • All possible, useful communications paths between functional entities should be explicitly stated. • The functional split between Media, Call Control, and Service planes should be rigorously maintained. This clear split is thought to be a prerequisite for the development of architectural models for Back End Services (BES) and the interworking with Intelligent Networks in the SCN. TD-105, Renaming the Signaling Gateways in TIPHON Reference Configuration (P. Pessi and M. Suoknuuti, Nokia), proposes a revision to DTS-02003 which distinguishes two signaling gateways (based on the role, protocols and mediation functions as distinct and complementary) between the IP domain and the SCN domain, one within the call signaling flow named Call Signaling Gateway (CSG) and one within the service flow named Service Signaling Gateway (SSG).

TD-106, Service Controller, Unified Call Controller, Resource Controller, and Refined Call Signaling Flows in TIPHON Reference Configuration (P. Pessi and M. Suoknuuti, Nokia), concludes that identifying and defining the Service Controller, Call Controller and Resource Controller functional blocks facilitates implementing distributed, highly-scalable gatekeepers and

gateways; separating CAU (between call controller and user terminal, or between two user terminals) and CAN (between two call controllers) information flows eases recognizing the distinct requirements of user-network and network-network call signaling interfaces. TD-058, Clarification on Where the SG11/Q5 IN Components May Fit in the TIPHON Reference Architecture (E. Martinez, Motorola), describes the SG11/Q5 view of the relationship of IN system to IP system and relates it to the TIPHON architecture. It concludes: • In many cases, H.323 systems will act as true peers to the IN network, rather than deriving all services from the IN network. This needs to be considered in the work of SG11/Q5. • Over time, it is the expectation that more and more service will be provided purely on the IP side; TD-058 suggests that SG11/Q5 take this evolutionary view into account. • It is understood that the PINT server is on the edge between the packet and circuit networks, rather than being a part of the packet network per se. • SG11/Q5 should consider the requirement that both the direct and GK-routed call model of H.323 be supported; the liaison appears to deal only with the GK-routed call model. • If the Gatekeeper can support SCF (service control function), the IP network may support the same SCE, SDF, SMAF and SMF management layer has shown in SG11/Q5 diagram. TD-082, Defining the Location of the Functional Components of the IN Architecture in the TIPHON Architecture (J. Talbot and K. Gorey, Nortel), discusses how the functions of the IN architecture could be incorporated into the TIPHON VoIP architecture; it proposes that: • The SSF (service switching function) be placed in the MGC function • The SRF (service resource function) be defined as a special instance of an MG

• That ETSI SPS3 (now SPAN3) should identify requirements for changes to the Megaco/H.gcp protocol to support some of the SCF to SRF functionality TD-111, Adopting a Pragmatic Approach to IPT-IN Interworking (B. Michaely, Vocaltec), promotes interoperability of current IN systems with expanding IPT systems through the prioritization of the IN-IP interworking standardization effort so that the short term market needs are satisfied at high priority, in parallel to a background effort for standardizing next generation IN and IPT systems. This pragmatic approach relies on the IPT system to receive control of calls originated from the SCN (IN), while acquiring access to the IN data by use of the signaling gateway and standard IN data access protocols, such as INAP queries (from SSF to SCF). The IPT elements do not need to expose full IN interfaces such as SSF or SCF - the required subset needs to be standardized.

FIREWALLS TD-094, Draft Firewall Requirements for IP Telephony (M. Shore, Nokia), is a tutorial paper discussing some potential design flaws in the H.323 Firewall Control Interface (HFCI) Internet draft proposal, the types of firewalls in widespread use (simple packet filtering, stateful inspection, application proxies, virtual private networks, circuit proxies, firewall control protocols), why they do not work with H.323 or encrypted signaling, and requirements for a firewall to support H.323.

CABLE PACKET NETWORKS TD-103, Interworking Between TIPHON and Packet Cable Networks (P. Guram, Motorola), proposes work, for either an existing WG or a new WG, to evaluate the architecture and signaling requirements to support interworking between a TIPHON-based network and Packet Cable network (cable modem/head-end router over HFC), and produce a suitable interworking TIPHON document for these two IP networks (as none currently exists). WG2 agreed to send a proposal to CableLabs to have discussions on how to consider packet cable networks within TIPHON.

BACK-END SERVICES ARCHITECTURE G. Manor (VocalTec) prepared a new version of DTS-02007 based on discussions within TIPIA and within the WG2 drafting sessions. The document was not available prior to its presentation, making discussion difficult. Several proposals were discussed on how to handle Back End Services (BES) in the functional architecture: • To create a new plane for BES • To merge the BES blocks of the SCN and IPN domains into one • To stop the vertical line (reference points) at the level of the Service Control.

DTS/TIPHON-02003, NETWORK ARCHITECTURE AND REFERENCE CONFIGURATIONS; PHASE III SCENARIOS 1 TO 4 (VERSION 0.2.1) J. Holme (Ericsson) is the DTS-02003 editor. The reference models were revised completely, resulting in a functional architecture model and a series of network architecture models, i.e., one for each of the TIPHON scenarios. New Annex on IN The need for a new annex on IN was discussed, and P. Guram (Motorola) produced TD-137, Annex diagramming the service layer interface to IN. It is a reflection of the discussions and agreement between ETSI SPAN3, ITU-T SG11 Q5, and TIPHON WG2. Because TD-137 contains details which were not discussed, an outline was prepared to support contributions; it will be included in the new draft of this deliverable. Progression of the Deliverable The result of the drafting sessions and subsequently discussions during the WG2 meetings is given in the version 0.3.0 of DTS-02003. An interim meeting was agreed to document the new architecture models developed during TIPHON 14. This should allow WG2 to minimize delay in achieving a stable draft of the deliverable. The editor will organize a two-day drafting meeting which may coincide with the

IETF Megaco drafting group meeting in New Jersey during the second or third week of September.

DTS/TIPHON-02007, NETWORK ARCHITECTURE AND REFERENCE CONFIGURATION FORB ACK-END SERVICES (VERSION 0.0.0) The editor added a number of editorial notes to DTS/TIPHON-02007 based on the discussions. Further contributions are required in order to progress the deliverable. The result of the work during this TIPHON meeting is in version 0.1.1 of DTS/TIPHON-02007.

LIAISON ACTIVITIES Results of Joint ITU-T WP4 of SG11/SPAN3/TIPHON Meeting TD-121, Report of Joint meeting ITU-T SG11/ETSI SPAN3/ETSI TIPHON on IN for Voice/Multimedia over IP (J. Vandenameele, Alcatel and WG2 chair), discusses the role of IN for TIPHON systems. It provides a joint action plan for use of IN for Voice (and Multimedia) over IP. WG2 discussed TD-121 in detail and agreed on several amendments. TD-121r1 is the report as approved by WG2. A second joint meeting is to be held on October 7 or 8, during TIPHON15. CableLabs TD-133, the proposed liaison to CableLabs, was discussed within the PMC. The PMC agreed to invite CableLabs to a meeting to discuss the interworking between packet cable networks and TIPHON systems. L. Spergel (Lucent, Vice-Chair External Relations) will produce the draft of the invitation. Outgoing Liaison Statement TD-128, Liaison Statement Related to IN for Voice (and Multimedia) over IP (J. Vandenameele, Alcatel and WG2 chair), is a liaison to ITU-T Q5 SG11, Q22 SG11, ETSI SPAN3, and ETSI SPAN6, providing a copy of TD-121r1, the approved report of the joint meeting Another joint meeting is proposed for Leipzig, Germany for 1/2 day, on October 7 (during TIPHON 15). WORKING GROUP 3, CALL CONTROL

G. Kimchi (Vocaltec) is the WG3 chair. TD-008r3 is the agenda. TD-015 is the report from this meeting. Contributors were required to be present (aliases and proxies were not allowed) during the WG3 session(s) to present, discuss and dissect their document(s) in order for their document(s) to be considered. The goals of the meeting were to review the first texts of the following work items: • DTS-03004.2 (2nd version of TS 101 321) Protocol for Inter-Domain Pricing, Authorization and Usage Exchange, Revision 2 • DTS-03009, Interworking Between H.450 and QSIG/DSS1 • DTR-03010, Requirements for a Protocol and an API that Allows a Gatekeeper to Control Policy Enforcement Elements • DTS-03011, Signaling for Basic Calls and Inter Domain Calls Between H.323 and SCN Terminals, TIPHON Phase 3 (Scenarios 0,1,2,3 and 4)

DTS-03004.2, OPEN SETTLEMENT PROTOCOL (OSP) FOR INTER-DOMAIN PRICING, AUTHORIZATION AND USAGE EXCHANGE, REVISION 2 TD-098, Corrections to ETSI TS 101 321 Version 1.4.2 (S. Thomas, TransNexus), identifies minor (no changes in content) errors in ETSI Technical Specification TS 101 321 version 1.4.2. It was agreed that TIPHON will correct those errors and issue a revised specification with version number 1.4.3. TD-102, Comments on RTS 101 321 Version 2.0.2 (S. Thomas, TransNexus), includes suggested revisions regarding the elements StartTime, EndTime and TerminationCause to version 2.0.2 for incorporation into a new draft of RTS 101 321.

DTS-03007, PACKETIZATION AND CODE-POINTS FOR THE TIA/EIA IS-641 E NHANCED FULL-RATE SPEECH CODEC TD-085, Proposal To Close Work Item DTS-03007 (R. Zwart, AT&T), proposes to stop the work on IS-641 packet formats for H.323 because of the recent decision of ITU-T SG16 to allow ANSI- 136 in H.323. Since SG16 is defining the codec and packetization formats of IS-641 as a part of ANSI-136, there is no reason to duplicate their work. There was agreement. WG3 requested that this document be agreed at the closing TIPHON plenary.

DTR-03010, INVESTIGATION ON THE REQUIREMENTS FOR AN API AND A PROTOCOL FOR THE CONTROL OF IP-B ASED POLICY ENFORCEMENT ELEMENTS BY A GATEKEEPER TD-093, IP QoS: Mechanism vs. Interface (M. Shore, Nokia), discusses the need for greater clarity in the distinction between signaling interfaces and mechanism, and in particular what is reasonable for TIPHON to specify in support of its architecture. M. Shore will coordinate the writing of an ID and present this to the RSVP Admission Policy WG at the next IETF meeting.

DTS-03011, SIGNALING FOR BASIC CALLS AND INTER-DOMAIN CALLS BETWEEN AN H.323 TERMINAL AND A TERMINAL IN A SWITCHED-CIRCUIT NETWORK (SCN), PHASE III TD-063, Feedback from Third TIPHON InterOps into Standardization Process (J. Elliger, ETSI STF 114), shows some areas of H.323 and TIPHON specifications that need to be enhanced to improve interoperability. Two problems, one with symmetric coders and one with coding and syntax of the Destination Address, have shown up during the latest InterOp Events. WG3 should decide whether to send a liaison to SG16. (See the WG6 report, below.) TD-074, Comparison Between H.323 Gatekeeper Routed and ISUP-Based Direct Routed Scenario 3 Calls Between Decomposed Gateways (B. Van Doorselaer and J. Bouwen, Alcatel), promotes the inclusion of architectures without gatekeepers as TIPHON compliant, and concludes that WG2 and WG3 should work on ISUP-based direct routed call scenarios. The first scenario (H.323/H.225/Q.931 Gatekeeper routed call scenario) shows that at two different stages (i.e., at the ingress MGC and at the egress MGC), a protocol interworking between ISUP and H.225/Q.931 has to be provided. This is not the case in the second scenario (ISUP-based direct routed call scenario) where the interworking complexity has been kept to a minimum level. Since complexity has its price (time to market, computational power required, testing, etc.) the second scenario (ISUP-based direct routed call scenario) deserves proper attention. For the first scenario, collapsing the MGCs with the GKs would reduce the call set-up time by at least four RTTs (round trip times), since during the call set-up procedure four H.225/RAS messages are exchanged (over UDP) and four H.225/Q.931 messages are exchanged (over TCP or UDP). If H.225/Q.931 uses TCP and not UDP, a higher number has to be taken into account. Therefore, an architecture where the functionality of MGC and GK are brought together in one entity deserves proper attention because it will enhance the call set-up performance. WG2, therefore, promotes the ISUP-based direct routed call scenario as a starting point for discussions in ETSI TIPHON WG2 and WG3. WG2 promotes the choice of the ISUP-based direct routed call scenario as the preferred one in chapter 4.1 of DTS-02003. TD-074 proposes the use of paragraph 5.2.2. (Direct routed call) of this document as a direct input for WG3 in the document specifying scenario 3, after moving the protocol-specific references to an informative annex. TD-088, Access Gatekeeper Procedures (J. Holm, Ericsson), presents procedures for separation of gatekeeper functions to two Gatekeepers, one to handle Access (e.g., user) aspects, and the other to handle network aspects. WG3 is concerned that it is premature to add procedures for services when the services themselves are not mature. TD-088 will be added as an informative annex to DTS-30011. TD-097, Generic Service Control Transport Channel (J. Holm, Ericsson), shows how a separate service channel may be opened to enable non-standardized services to be executed on PC clients (i.e., H.323 Terminals) and how it may interact with the Gatekeeper and the GW (GateWay). TD- 097 was presented for information only and will be presented at the SG16 expert meeting in Berlin, August 1999 (report to be published in CSR Vol. 10.9).

OTHER CONTRIBUTIONS TD-046, iNOW! Implementers Guide, Special Interest Group (SIG) (L. Moscovici, Vocaltec and SIG Chair) proposes to clarify, correct and complement issues concerning the iNOW! v2 profile, in order to enable smooth interoperability (see WG1 and WG6 reports). The members were requested to verify that the document follows the TIPHON specifications and guidelines. The STF was requested to create a document that details the differences between the TIPHON H.323 profile and the iNOW! H.323 profile, and post it to the WG3 mailing list as soon as possible.

INCOMING LIAISONS TD-028, Reply to Liaison Statement on SS7 Information Transport Over Intermediate H.323 Network (I. Spiers, Marconi Communications), is a liaison from ETSI SPS1 (now SPAN1) to EP TIPHON WG3. It is SPS1’s view that ISUP messages should be transported transparently (not mapped) between two gatekeepers and where an intermediate gatekeeper does not use the information in the SS7 message. An ISUP message does contain information that should be kept private (for example the CLI information, data protection). The use of a mapping technique will compromise the security/privacy requirements due to the fact that intermediate gatekeepers will, because of mapping, have unrestricted access to this information. SPS1 wants to learn more on the proposed extension to H.225.0 for the encapsulation of ISUP messages. SPS1 also asks if this extension allows for transparently transporting other SS7 protocols.

CURRENT WORK ITEMS

DTS/03004.2 First Text at TIPHON 13 meeting DTS/03008 First Text at TIPHON 13 meeting (see security session report, below) DTS/03009 Outline and Table of Contents at the TIPHON 14 meeting DTR/03010 Outline and Table of Contents at the TIPHON 14 meeting DTS/03011 Outline and Table of Contents at the TIPHON 14 meeting

FUTURE AREAS OF STUDY • Identification of scenarios (0 - 4) calls at call-setup, implications when no identification is possible. • Phase 3 issues, addressing both GRC and DRC and transported (e.g., Half-Interworking), must demonstrate seamless interworking with Phase 2. • Analysis of interworking cases where TIPHON acts as a public network (scenarios 1 & 2) – this relates to 12TD-27. • Analysis of interworking of scenario 3 between foreign networks (e.g., SS7 to TIPHON to QSIG/GSM and others, and vice-versa) where the TIPHON public transit network has to mediate the call. • Applicability of ITU-T H.341 (and/or other management solutions) for the management functions of TIPHON systems. • User and Terminal Roaming procedures, which require User Identification, Home Network Identification, assorted security mechanisms and accounting functions (specifically reconciliation). • H.323 call signaling procedures and/or changes to enable user and terminal mobility (for scenario 1 and 2 hand-over when the IP terminal changes addresses during a call). • Direct-Routed-Calls as they relate to TD-088. • Contributions directed at the 03004.2, 03008, 03009, 03010, and 03011 WORKING GROUP 4, NAMING, ADDRESSING

J. Horrocks (DTI) is the WG4 chair. TD-016r3 is the meeting report and TD-009r1 is the agenda. This was a joint meeting with NA2/NAR-IP. ITU-T SG2 TD-035, Prospects for a Global Code (J. Horrocks, DTI and WG4 Chair), summarizes the discussions in SG2 and the various issues and problems that had arisen. Telecom Australia and some other members of TIPHON applied in 1998 to ITU-T SG2 for the temporary reservation of a

global code for a trail of applications using IP. A prolonged debate occurred at the May, 1999 SG2 meeting, but no decision was made. The issue now is to consider what further actions if any are needed. There was general agreement that it would be very difficult to achieve positive decisions from SG2 in the future on any matters relating to global codes. TD-035 suggests that even though the door is open to propose (to the September SG2 Q10 rapporteurs’ meeting) a short service description for the “Full Feature Service” that would use a new global code, an easier solution would be for any operator wanting to pursue the trial and possible introduction of a service using a global code to do so as an implementation of UPT (i.e., using +878 which is reserved for UPT). T. Holmes (BT) advised that any operational use of the UPT code would require an application to SG2 to convert the reservation into an assignment, and that the issue of the administration of the non-country-specific parts of the UPT code would need to be resolved. In any case, it would be courteous to advise the September SG2 Q10 meeting of the current state of plans within ETSI. TD-109, Liaison Statement from TIPIA, states that four operators (MATAV, Omnitel, PanTel, Telekom Austria), plan to start service trials including UPT global service code trials in September 1999, and would use a “dialing code” unless, and until, the global code becomes available. These operators would like to see work items 04005 and 04006 progressed as quickly as possible. There was a fairly wide ranging discussion of the issues, Telecom Austria wants to continue all relevant work as soon as possible, and some other participants want to drop all work related to global numbering. The following conclusions emerged: • The Chair will tell the Q10/2 rapporteur that TIPHON participants are not proposing to make inputs to any new service descriptions and are not pursuing the case or a separate global code. • The four operators are entirely free to undertake whatever trials they wish relating to a UPT service with global numbering and to make approaches to SG2 about the use of the UPT code, but there is inadequate support/consensus for these approaches to be made as TIPHON inputs • WG4 currently has no work item relating to the description of trials on numbering, whether for a global or a national numbering arrangement; a work item could be proposed but not has been proposed as yet. • Work items in WG4 would need to be supported by four ETSI members who participate actively in the discussions. • Work item 04005, Rationale for the Global Code and UPT, will be suspended until the October meeting because DTI, Nokia IP Telephony and BT no longer wish to support the item, but the item could be resumed if three other ETSI members offer active support including attendance at TIPHON meetings; if such support is not forthcoming by the October meeting, then the work item will be canceled. • Work item 04006, Functional Requirements and Architecture for E.164/IP resolution, will be divided into two possible items: one on issues for the main existing numbering schemes, the other on issues related to a global code. There appeared to be significant support for the first item; the Chair asked members to identify in more detail what needs to be done and provide inputs to WG4 at the next meeting. A detailed scope will then be produced and the support criteria applied. For the second item, work was suspended because DTI, Nokia IP Telephony, BT and AT&T no longer wish to support the item; it will be handled the same as WI 04005. It was noted that if IP technology is to be used to provide UPT, then it would be desirable, but not essential, to supplement the UPT recommendations in various ways including access by IP terminals over SCNs.

ARRANGEMENTS FOR WORKING WITH NA2 AND RELATIONSHIP TO IETF ENUM The Chair reported that agreement has been reached with NA2/NAR-IP that matters relating to numbering for services provided over VoIP would be handled at joint meetings with WG4 held during the TIPHON meetings. The objective is to ensure that discussions take place in a single joint group. TD-042, ENUM (J. Horrocks, DTI and WG4 Chair), outlines the planned area of work of a new group ENUM (tElephone NUmbering Mapping) in IETF. T. Holmes (BT), who had attended the recent IETF group, added that ENUM is in the process of receiving its charter within IETF but that the exact area of work remains unclear. The group will focus on calls from IP to SCNs and issues of the compatibility of terminals that use E.164 numbers, plus the issues of different

service providers who may wish to compete openly to furnish the directory required by clients to reach the desired telephone numbers. Even though this area of work could be important, it is not yet certain whether there will be significant input and support. T. Holmes (BT) outlined the recent decisions by which ETSI has become a member of the Protocol Support Organization within ICANN and, although members are free to make their own individual inputs to IETF, the desirability of ETSI members coordinating inputs to IETF and ICANN. TD-070, Comments on TIPHON WG4 Relationship with IETF WG ENUM (T. Holmes, BT), requests that the agreements made in Heidelberg continue to be upheld: that NA2NAR-IP assume the responsibility as the channel into the ENUM debate from within ETSI, and that continued close cooperation with TIPHON WG4 be viewed as a key building block as the ETSI input is developed. TD-075, Comments on Working with IETF WG ENUM, (A. Dilber, AT&T), concludes that TIPHON WG4 should contribute to the IETF ENUM group when appropriate by cooperating with NA2NAR-IP, who will be the interface for ETSI when dealing with the IETF on Numbering and Addressing issues; formal arrangements to ensure that the required cooperation takes place should now be discussed. It was decided that: • Discussions on numbering for VoIP would take place at the joint WG4 / NA2/NAR-IP meetings and via a joint email exploder that will be set up by L. Vreck (ETSI). Wherever relevant and possible (in view of the timing), the existing TIPHON liaison procedures will be followed. • Discussions on other IP numbering/naming issues will be handled separately in NA2/NAR-IP. • T. Holmes (BT) will normally be the point of contact between TIPHON /NA2/NAR-IP and IETF for numbering issues. Note: The PMC has asked that individuals nominated by TIPHON according to current practice should handle protocol and architecture issues.

DTS-04003, NAMING AND ADDRESSING; SCENARIOS 1, 2, 3 AND 4 (NUMBERING ) TD-036r2, TS 101 324, TIPHON; Numbering; Scenario 1, consists of minor additions and changes to TS 101 324; it was updated with several further changes. It was noted that Scenario 0 (all IP) needs to be covered; it will be addressed in a future amendment. The draft was approved in WG4 for submission to the TIPHON plenary.

DTR-04004, GUIDE TO NUMBERING OPTIONS J. Horrocks (DTI) introduced the draft, TD-037©, DTR-04004v0.02, TIPHON; Guide to Numbering Options for Public Networks Based on VoIP Technology. It was discussed and updated with several further changes. There was some discussion about whether further work is needed on number portability. The group decided to review this at the next meeting. Members were asked to review the outputs of the number portability task group: • TR 101 119 (1997): High level description of number portability • TR 101 118 (1997): High level network architecture and solutions to support number portability • TR 101 12 (1997): Numbering and addressing for number portability • EG 201 367: IN and intelligence support for service provider number portability • TR 101 697 v1.1.1 (1999): Guidance on choice of network solutions for service provider portability for geographic and non-geographic numbers • TR 101698 v1.1.1 (1999): Administrative support of service provider number portability Members were asked to propose the areas (if any) that need work related specifically to IP based networks. The draft was approved in WG4 for submission to the plenary.

JOINT SESSION WITH WG7 ON GLOBALLY UNIQUE PERSONAL USER IDENTITY BASED ON IMSI R. Stastny (OeFEG) presented 13TD-056, which proposes the introduction of an IMSI address to support mobility. After significant discussion, 13TD-056 was accepted as a possible solution,

however, further work is needed to analyze the issues in more detail. In particular, members were asked to prepare contributions to the next WG7 meeting to compare and contrast the functions that the IMSI is used for in mobile SCN networks and the functions that the NAI is used for in IP networks to help to identify exactly what is needed. The expectation is that IMSIs will be needed to support roaming on IP terminals when connected to SCN networks. It was noted that IMSIs and mobility are not currently supported in PSTN/ISDN. (See also the WG7 report, below.) WORKING GROUP 5, QUALITY OF SERVICE M. Buckley (Lucent) is the WG5 Chair. TD-017 is the meeting report; TD-10r1 is the agenda.

DTR-05003, A SIGNALING SYSTEM TO SUPPORT TIPHON QUALITY OF SERVICE TD-032, Architecture: Leading Design from QoS and Regulatory Constraints (S. Cadzow, ETSI STF 114), discusses the impact of QoS on the TIPHON architecture. A circuit mode resource has only two states: available and busy. A packet mode resource has the same two states, but for each packet. For a packet mode service, QoS is a continuum. TD-032 suggests that QoS needs the architecture to bring together solutions that make binary decision trees possible: Can the network provide and maintain the QoS required by the user? Existing networks are deficient. Existing protocols need to be considered in the architecture. TD-034, Modification to the TIPHON Reference Model to Support Transport QoS Aspects (G. Kimchi, Vocaltec AND WG3 Chair), presents a diagrammatic modification to the TIPHON reference model that will allow specifications of QoS aspects, as required for WG5, and requests that WG2 adopt this modified reference model. TD-034 and TD-073 (discussed in WG2, above) both indicate the need for the addition of a Transport Plane in the TIPHON architecture in order to adequately model QoS issues. TD-059, QoS for H.323 Calls over DiffServ Networks (C. Prehofer, Siemens), outlines an approach for interfacing H.323 gatekeepers and DiffServ edge routers to control QoS. The access to DiffServ networks is controlled by boundary or edge devices, which do not handle H.323 calls. Hence these devices need to be instructed about the session data by H.323 gatekeepers in order to treat the H.323 payload properly. TD-059 gives a reliable solution for the QoS problem in specific environments. TD-059 asks TIPHON to discuss whether this proposal might be a recommended way for achieving QoS in TIPHON-compliant VoIP networks. TD-093, IP QoS: Mechanism vs. Interface (M. Shore, Nokia), outlines the limitation of existing mechanisms like DiffServ and RSVP for providing hard end-to-end QoS guarantees, particularly the absence of suitable interfaces and protocols. TD-093 proposes working closely with appropriate bodies such as the IETF to ensure all elements of a solution have been addressed. TIPHON will need to define and then input requirements. TD-096, A Layered Network Architecture for Voice and Multimedia over IP (L. Klostermann, Ericsson), proposes the need for a layered approach to QoS and indicates the desirability of separating H.323 signaling from QoS signaling. It was agreed that the following be added to the TIPHON architecture: • A transport plane • Two functional elements 1) A QoS policy decision element in the service layer of the application plane 2) QoS policy enforcement element in the transport plane • An information flow would be required between these • The mechanism adopted would be independent of the QoS techniques used in the transport layer These requirements were fed into the WG2 discussions on the TIPHON architecture G. Manor (Vocaltec) produced draft text, DTR-05003 v.0.1.1, which was discussed and agreed as initial text. Areas for further contributions were identified and a number of text revisions agreed.

QOS TESTING AT NEXT TIPHON INTEROPERABILITY EVENT A joint meeting was held with WG7 to address testing QoS issues at the next TIPHON InterOp event. TD-041, Summary of QoS Testing from InterOp #3 (S. Cadzow, ETSI STF), requests test scenarios be drawn up for QoS testing at the next testing event at the end of Q4 1999. This was agreed. TD-114, Joint ITU-T Q13/12 & ETSI TIPHON Test Event for Objective Speech Quality Assessment Solutions (H. Klaus, Deutsche Telekom and Rapporteur ITU-T Q13/12), provides details of activities underway in ITU-T on objective speech quality assessment solutions. Q13/12 is developing P.86x (objective speech quality measurement) with Determination planned in June 2000. TD-114 suggests that ITU-T representatives should participate in the next round of TIPHON tests and that test data should be obtained using a number of the objective speech quality algorithms being considered by ITU-T. It was agreed that such a collaboration would be very welcome. A group composed of experts from ITU-T and WG5 together with the STF members agreed to draw up detailed plans for how this testing would be performed. TD-132, Requirements for Joint ITU-T Q13/12 & ETSI TIPHON Test Event (H. Klaus, Rapporteur ITU-T Q13/12), details the framework for a joint test event on speech quality. TD-049, Use of Ascom PACE and VoIP-Simulator (R. Wu, and P. Juric, Ascom) presents a MATLAB software application simulation of the effects of packet loss on speech quality and provides an algorithm for speech quality assessment to be used for the upcoming ITU-T SG12 benchmark.

RTR-05007, GENERAL ASPECTS OF QUALITY OF SERVICE (QOS), ADDITIONS AND CHANGES TO TR 101 329 The latest approved version, v2.2.1, of TR 101 329 has now been published. TD-081, Speech Quality Test Results of IP Equipment in a LAN Environment (J. Pomy, Robert BOSCH GmbH), provides data on performance measurements for two different commercial IP gateways and two different IP PC clients. The IP gateways are connected to PBXs via 2 Mbit/s links with QSIG signaling. Four wire subscriber interfaces were used, in accordance with ES 201 168. The coding selected is G.723.1 (6.3 kbit/s) with voice activity detection and integrated echo canceling activated. It was noted that the echo cancellers in both gateways do not comply with G.168. It is likely that additional echo cancellation would be needed in an operational network. Three scenarios were tested and the speech transmission end-to-end performance was not found to be acceptable for long term business applications. Using the E-model, expected R values were predicted for end-to-end QoS in a typical set up. The R values range from 0 (all users dissatisfied) to 68 (many users dissatisfied). It was noted that degradations other than those measured may also have been present, which would further degrade system performance. TD-095, Clarification of QoS (F. Howett, Nortel), indicates that a number of factors other than those primarily addressed in TR 101 329 were identified in ETR 138 (QoS indicators for open network provision of voice telephony and ISDN). The term “QoS” is often taken to be a measure of the end-to-end speech performance of a telephone connection, but this meaning is excluded from the EC (European Commission) Voice Telephony Directive and the current version of ETR 138. This creates two different perceptions of QoS. It was suggested that the term Voice QoS (VQoS) should be adopted in the TIPHON studies to clarify the difference in the two approaches. There was no consensus on this change. TD-113, Relations Between MOS and R Values for Results of VoIP Simulation (R. Scheerbarth, I. Kliche, and H. Klaus, Deutsche Telekom), is based on 11TD-064 and presents E-model calculations. ITU-T G.109 provides classes of user satisfaction, based on the R-values of the E- model. TD-113 maps the set of VoIP test cases and their assessed MOS scores in 11TD-064 into R-values. The results show that the limits for QoS classes defined in DTR-05007 table levels of network degradation (3%, 5%, 25%) are not sufficient. The test results show that the evaluation for voice signals with packet loss >10% is far below the quality threshold.

Due to insufficient time, further changes to the deliverable were not discussed.

NEW WORK ITEM ON MEASUREMENTS OF NETWORK AND TERMINAL PERFORMANCE It was agreed that a new work item should be created to collect together data on measurements of network and terminal characteristics and performance parameters. This would include measurements of network characteristics (mean throughput delays, packet loss, jitter statistics), measurement of equipment characteristics in relation to TIPHON terminal classes, and studies of the effect of network and equipment performance parameters on voice quality in TIPHON systems. It would also include modeling of TIPHON systems in relation to voice quality of service.

LIAISONS TD-138 is the liaison statement from WG5 to ITU-T SG2 Q2 and Q5 (M. Buckley, WG5 Chair). It notes the ongoing work of TIPHON WG5 on various aspects of QoS performance requirements for IP telephony and refers SG2 to the ETSI TIPHON web site for further information. WORKING GROUP 6, VERIFICATION M. Blaschitz (Telekom Austria) is the WG6 chair. TD-018 is the meeting report and TD-011 is the agenda.

RESULTS Table 2 provides the goals and results of WG6.

Deliverable Goal Achievement Scheduled Approval RTR/TIPHON-06002 Verification Demonstration and Suggested for TIPHON 14 Interoperability (VDI) Activities Version 2 TIPHON approval RTR/TIPHON-06003 Verification Demonstration and First text Stable draft TIPHON 16 Interoperability (VDI) Activities Version 3 RTS/TIPHON-06005 Test Specifications Version 2 To be approved Suggested for TIPHON 14 by TIPHON TIPHON approval RTS/TIPHON-06006 Test specifications Version 3 First text TIPHON 17 DTS/TIPHON-06007 PICS Proforma for H.450.1 To be approved Suggested for TIPHON 14 Supplementary Services by TIPHON TIPHON approval DTS/TIPHON-06008 PICS Proforma for H.450.2 To be approved Suggested for TIPHON 14 Supplementary Services by TIPHON TIPHON approval DTS/TIPHON-06009 PICS Proforma for H.450.3 To be approved Suggested for TIPHON 14 Supplementary Services by TIPHON TIPHON approval DTS/TIPHON-06010 PICS for OSP None Stable draft TIPHON 16 DTS/TIPHON-06011 PICS for TIPHON Clients None Create work item TIPHON 18 DTS/TIPHON-06012 PICS for TIPHON Gateways None Create work item TIPHON 18 DTS/TIPHON-06013 PICS for TIPHON Gatekeepers None Create work item TIPHON 18

Table 2. Goals and Results of WG6.

INTEROPERABILITY EVENTS TD-053, Report on 3rd TIPHON InterOp in Sophia Antipolis, June 21-25, 1999 (R. Scholl, ETSI STF 114), puts forward various suggestions on how to improve InterOps, the interaction with the (abstract) standards process, and the collaboration with IMTC. The following action items were identified for the STF: Remote InterOp Testing • Continue work on easy-to-use recipe for companies to connect via ETSI ISDN-router; do some tests with several companies to make sure that recipe is “fool-proof” (on the basis of TD-065).

• Using the experience from these tests, prepare a remote InterOp event together with IMTC, maybe even before the September-event in Hawaii (on the basis of TD-064). TIPHON members are strongly encouraged to make extensive use of the virtual InterOp facilities provided by ETSI. Face-to-Face InterOp • Prepare Hawaii SuperOp together with IMTC. • Be the person responsible (together with someone from IMTC) for collecting and returning feedback from InterOps to the standards process. A final plenary should be organized at the InterOp to collect the feedback. • Prepare speech quality measurement event at the SuperOp (see TD-132). Virtual InterOp Meeting Place (VIMP) and Web-Based Services • Improve the web-based services to make InterOp testing even more efficient. Write requirement specification. Add specifically a PICS statement for Client, Gateway and Gatekeeper, which WG6 is going to define. • For SuperOp, IMTC uses registration via fax. For InterOp after the SuperOp, need to put VIMP on a firm basis. Requirement specification needed based on previous experiences with VIMP. Three new work items, which are supported by INFONOVA, Telekom Austria, Nortel, and Telenor, have been approved:

DTS-06011 PICS for TIPHON Terminals DTS-06012 PICS for TIPHON Gateways DTS-06013 PICS for TIPHON Gatekeepers The Work Items have the following schedule:

TOC and Scope: TIPHON 15 Stable Draft: TIPHON 16 WG6 Approval TIPHON 17 TIPHON Approval TIPHON 18 TD-063, Feedback from (third) TIPHON InterOps into Standardization Process (J. Elliger, STF 114), shows some areas of H.323 and TIPHON specifications that need to be enhanced to improve interoperability. Two problems, one with symmetric coders and one with coding and syntax of the Destination Address, have shown up during the latest InterOp Events. WG3 should decide whether to send a liaison to SG16. The technical issues raised have been forwarded to WG3. A liaison statement from WG3 to SG16 is encouraged on the issue of symmetric coders.

VIRTUAL INTEROPERABILITY MEETING PLACE; I MPLEMENTERS NET; TEST CENTER WG6 supports the creation of a permanent InterOp facility. TD-065, Recipe to Use the TIPHON InterOp Router (J. Elliger, ETSI), describes how to connect a stand-alone Workstation and a Remote LAN to the ETSI InterOp Router using Microsoft Products. A connection can be established using other products as the description on how to use products of other vendors is added. TD-065 was approved for incorporation into RTR-06003, Verification Demonstration and Interoperability (VDI) Activities Version 3.

DTS-06005, TEST SPECIFICATIONS VERSION 2 TD-040, Summary of Security Testing for InterOp, and TD-041, Summary of QoS Testing from InterOp #3 (both from S. Cadzow, ETSI STF 114), conclude that a work item is required to address security testing and QoS testing, respectively, for availability by the end of Q4 1999. It was agreed to start work on developing security and QoS testing procedures and test cases in the framework of the WG6 test specification RTS-06006, Test Specifications Version 3. TD-046, iNOW! Implementers Guide, Special Interest Group (SIG) (L. Moscovici, Vocaltec and SIG Chair), was submitted by S. Cadzow (ETSI STF 114); it proposes to clarify, correct and

56 Vol. 10.8 Copyright © CSR 1999 August-B 1999 COMMUNICATIONS STANDARDS REVIEW complement issues concerning iNOW! v2 profile, to enable smooth interoperability. A liaison will be drafted to iNOW! SIG on testing to ensure that their work does not conflict with WG6 activities. The liaison will be approved on the exploder. (See the WG 1 and WG3 reports, above.) TD-062, Test Specifications for ETSI Technical Specification TS 101 321 V1.4.2 (1998-12) (S. Thomas, TransNexus), contains OSP test cases and was approved as part of RTS-06005. TD-067, DTR/TIPHON-06005 V0.1.3 (R. Scholl, ETSI STF 114), was approved with modifications and will be presented to the TIPHON 14 plenary for approval. TD-089, Test Cases for In-Band Information before Active Phase and During the Release of a Call (J. Holm, Ericsson), was approved as part of RTS-06005, Test Specifications Version 2. It adds test cases for when the SCN returns in-band announcements but no connect message is received (e.g., change number interception, vacant called party number, etc.) TD-114, Joint ITU-T Q13/12 and ETSI TIPHON test event for objective speech quality assessment solutions (H. Klaus, Deutsche Telekom), was presented in a joint session with WG5. It was decided that the proposed tests should take place during the SuperOp in Hawaii. A drafting group defined the requirements for the tests in terms of equipment and resources. The result of the drafting group is TD-132. It contains a detailed description concerning the requirements for the QoS testing at the SuperOp in Hawaii. G. Boulay (France Telecom) announced the availability of a network simulator and will provide the URL for additional information. The STF will check if, and how, the tool can be used at InterOp. TIPHON members are invited to participate or contribute. The contact point for queries is J. Ellinger (ETSI STF 114). Echo and conversational tests will also be conducted during the event. More detailed information will be provided by F. Kettler (Deutsche Telekom, Head Acoustics) via the mailing list.

TEST SPECIFICATIONS FOR TIPHON SYSTEMS DTS/TIPHON-06006 TD-066, Proposal to Merge IMTC and TIPHON Test Specification (J. Ellinger, ETSI STF 114), was presented; there were significant discussions. It was agreed not to target a complete merging of the IMTC and TIPHON test specifications but rather to ensure that tests would not be duplicated during an InterOp event. The same functionality should not be tested twice. The document however was approved as the basic structure of RTS-06006, Test Specifications Version 3. TD-084 (J. Ellinger, ETSI STF 114) proposes integrating “Long Term Tests” into the existing test specifications. At the Boston Interop several problems were detected, as some manufacturers implemented a new mechanism to check if the remote peer is still present. This mechanism forced many disconnects of calls before they were really finished. There is a need to add a test for this feature to the test specification. TD-124, New IMTC Scoring Scheme (J. Ellinger, ETSI STF 114), requests that ETSI decide whether to adopt the IMTC new scoring sheet for WG6 test specifications. WG6 decided not to adopt the schema at this time.

WG-DESCRIPTION (TIPHON-NET, I MPLEMENTERS NET, I NTEROP EVENTS) DTS/TIPHON-06002 TD-052, DTR/TIPHON-06002 v.1.3, Verification Demonstration and Interoperability Activities (R. Scholl, ETSI STF 114), is proposed for TIPHON approval at this meeting.

WG DESCRIPTION (TIPHON-NET, I MPLEMENTERS NET, I NTEROP EVENTS) DTS/TIPHON-06003 TD-064, Guidelines to a Remote InterOp Event (J. Elliger, ETSI), suggests that, to further enhance the ability to test interoperability of VoIP, in addition to face-to-face InterOp Events, remote InterOp events could be organized using the TIPHON InterOp Router or the public Internet. These Remote InterOp Events could also be used to check the status of implementations and to qualify them to participate in face-to-face InterOps. As there are no other differences between Remote InterOp Events and face-to-face InterOps than the distance between the

participants, the test specification has to be identical for both events. TD-064 was approved to be incorporated into RTR-06003, Verification Demonstration and Interoperability (VDI) Version 3. TD-061, TIPIA Profiles for ETSI Technical Specification TS 101 321 (S. Thomas, TIPIA), describes TIPIA’s desired profiles for ETSI Technical Specification TS 101 321. TIPIA requests that TIPHON WG6 give priority to these profiles in designing interoperability tests for TS 101 321.

PICS PROFORMA FOR H.450 SUPPLEMENTARY SERVICES The following documents are proposed for approval by TIPHON 14. • DTS-06007, PICS Proforma for H.450.1 Supplementary Services • DTS-06008, PICS Proforma for H.450.2 Supplementary Services • DTS- 06009, PICS Proforma for H.450.3 Supplementary Services

WORK ITEM FOR PICS PROFORMA FOR OSP A new WI, DTS/TIPHON-06010, PICS for OSP, was approved with support of the following ETSI member companies: INFONOVA, Telekom Austria, TransNexus, and France Telecom. The document is scheduled for Working Group approval at TIPHON 15 and for TIPHON approval at TIPHON 16.

WG6 PARTICIPATION AT SPECIAL EVENTS, CONFERENCES, ETC. A presentation concerning WG6 activities, the “Single Voice and Data Infrastructure,” was made in London on July 20, 1999.

OTHER HIGHLIGHTS TD-044, iNOW! V2 Profile, Test Plan & Reference Configuration, Special Interest Group (SIG) (R. Smithers, Mier Communication), proposes the following IMTC SIG tasks: • Propose Test Plan and Reference Configuration in conjunction with the CoIP test plans • Coordinate with IMTC CoIP activity • Revise the document • Submit the document to IMTC ballot (August) • Release iNOW! Test Plan and Reference Configuration Document (September) TD-045, IMTC iNOW! - Terminal Profile (V. Kumar, Intel), extends the iNOW! profile and interoperability out to the terminal endpoint. This is based on H.323 Annex F (Simple Endpoint Type) with H.245 (control) optional. The scope of the terminal profile is endpoint to gateway (brand A to B) or endpoint to gatekeeper ( brand A to/from B) interoperability and terminal to phone service. It does not consider phone to terminal, terminal to/from terminal interoperability, fax, directories, or enhanced services. Public testing is planned at SuperOp in September. WORKING GROUP 7, WIRELESS R. Zwart (AT&T) is the WG7 Chair. TD-019 is the meeting report; TD-012r2 is the agenda. WG7 held a joint session with WG4 to discuss 13TD-56 on the use of IMSI for user identification. The main goal for the meeting was WG7 approval of DTR-07001, Analysis of Existing Roaming Techniques Applicable to TIPHON Mobility. TD-054, Annex H (User and Service Mobility in H.323) Proposed Architecture (E. Martinez, Motorola), was received for information. It will be presented to SG16 Q11-15 in August (reports to be published in CSR Vol. 10.9). SG16 has recently approved new work to start on mobility for H.323. This will be dealt with in Annex H of H.323. TD-054 proposes that H.323 mobile will provide for the convergence of fixed and mobile networks and explains how mobility may be addressed in H.323, in particular by extending the H.323 architecture with a so-called Wireless Call Server. The author proposes that H.323 mobile be used as the basis for the next generation of mobile communications technology in Europe, UMTS. The contribution stirred a lot of discussion. The questions in WG7 focused on some confusion about the exact goals of this new

group; e.g., is the intention of this proposed architecture to solve mobility for H.323 or is the intention to bring wireless access possibilities to H.323? Generally, the explained solution was seen as conflicting with the general attempt within TIPHON to work towards a layered architecture. TD-096, A Layered Network Architecture for Voice and Multimedia over IP (L. Klostermann, Ericsson), was presented in several working groups. In WG7, section 5.4.2 of the contribution was discussed. TD-096 proposes to accept a layered architecture as a principle for TIPHON architecture work; it presents an example of an architecture being discussed in 3GPP. It was suggested to use the given example for the section on 3GPP in DTR-07001. In the discussion, questions were raised as to the effects of layering on the architecture; concerns were expressed by some participants with what was seen as a split of the architecture into separate networks (i.e., an IP and a “switched” environment). WG7 supported the suggestion to adopt a layered architectural approach, however since the effects obviously have a wider impact than just WG7, it was agreed to also follow the ongoing work in WG2.

MOBILITY TD-107, Extending TIPHON Reference Configuration with User Controller and User Roaming/Registration Flows (P. Pessi and M. Suoknuuti, Nokia), proposes that the registration flows (R) should be approached separately from the rest of service flows, and that WG7 define the extensions to the TIPHON reference configuration as follows: • The functional block called User Controller (UC).

• The information flows “RA” (H.323 registration), “RU” (user roaming/registration flow), “RUA” (between UC and CC, call controller) and “RUB” (between UC and SG, signaling gateway). • The TIPHON user roaming recommendation in DTR-07001, Analysis of Existing Roaming Techniques Applicable to TIPHON Mobility, should be based on the reference configuration model below. • A detailed extension specification should be included in DTS-07003, Mobility and Access to Wireless Systems; Extensions to Requirements, Architecture and Protocols. TD-107 suggests a new functional entity, the “User Control” box, with some associated reference points. Details of this functional block are to be addressed in DTS-07003. After some clarification and discussion, it was agreed that the proposed element can be added to section 7 of DTR-07001. The proposed text will be adapted to align with the layered architecture approach as discussed in WG2. Mobile IP/ROAMOPS section for DTR-07001 (P. Pessi, Nokia), was accepted for the evaluation matrix in section 6 of DTR-07001. TD-119, GPRS Section for DTR-07001 (S. Faccin and P. Pessi, Nokia), was accepted for the evaluation matrix in section 6 of DTR-07001. Some questions were raised whether it should be mentioned explicitly that GPRS currently does not explicitly support voice applications. This led to the observation that different sections of the document address different layers. This aspect can more easily be addressed when a layered architecture approach for TIPHON has been defined. TD-120, Support of IPv6 in UMTS (Bouygues Telecom), explains how IPv6 is better suited for mobile environments, and how mobility mechanisms provided in IPv6 can work with the Mobility Management layers of UMTS to improve the efficiency of the MM when interworking between an IPv6 and a UMTS network. TD-120 was seen as very interesting to the ongoing discussion in WG7, however, it was also seen to be out of scope of the current work in WG7, since the contribution was directed towards a UMTS environment and primarily addresses the IP layer. A short editing session was held to incorporate contributions TD-119, TD-118, TD-120 and 13TD- 146 (see below, under Liaisons) into DTR-07001, Analysis of Existing Roaming Techniques Applicable to TIPHON Mobility. This work was not concluded at the end of the editing session.

LIAISONS TD-026, liaison from EP UMTS, informs TIPHON WG7 of their work on VHE (Virtual Home Environment) and requests that EP UMTS be informed in detail on TIPHON’s views and requirements on the use of VHE. There was some discussion. Generally, it was agreed that WG7 does not yet have a clearly defined view of its requirements for and use of VHE. It was decided to send a reply to EP UMTS to inform them of this. Telia volunteered to draft a reply to this liaison. It was also suggested that WG7 draft its requirements on mobility services, which could lead to requirements on VHE to be input to EP UMTS. TD-055 (J.R. Elwell, TC32 Chair) is a liaison from ECMA TC32; it thanks TIPHON WG7 for its liaison, and offers support in the area of personal user mobility in private networks. No direct action was taken in response; however, when a stable draft of DTR-07001, Analysis of Existing Roaming Techniques Applicable to TIPHON Mobility, is available, it will be sent to ECMA TC32 for comments. TD-086, Liaison Statement: Current Status of CTM (Cordless Terminal Mobility) within ETSI (J.E. Navarro, Alcatel and ETSI) advises TIPHON WG7 on the status and application of CTM roaming technology. It was suggested not to include CTM roaming in the WG7 deliverables. The suggestion was accepted and references to CTM in DTR-07001 will be removed. 13TD-146, Liaison from 3GPP SA2 (Telia), thanks TIPHON WG7 for its liaison and provides WG7 with information on its current architecture. The architecture diagrams as well as the explanations on the views on Mobile IP in 3GPP were taken as input to section 5 of DTR-07001. TD-130, 3G.IP Liaison to TIPHON (R. Zwart, AT&T), notes that the 3G.IP Focus Group has been formed to produce a network architecture for an all-IP based 3G mobile system. This will be based on a direct evolution from GPRS and will have both UTRAN and EDGE radio access options. The work will support the standards activities in ETSI, 3GPP and elsewhere by defining concepts and carrying out feasibility studies for the architecture. The 3G.IP Focus group was contacted by the TIPHON chair; this liaison responds to that message. 3G.IP is interested to learn more of TIPHON’s activities and invites a TIPHON delegation to come to the next 3G.IP meeting to present its work.

JOINT MEETING WITH WG4 The joint session discussed 13TD-56, Globally Unique Personal User Identity (PUI) Based on IMSI (R. Stastny, Telekom Austria), which proposes IMSI (International Mobile Station Identity) as an appropriate mechanism to allow user identification in TIPHON, since it would easily allow roaming between GSM and TIPHON networks. 13TD-56 also requests the start of a new work item in WG7 to investigate the use of smart card technology in TIPHON. There was much discussion. One of the objections was that IMSI is only useful in the context of interworking with GSM. This will not apply in most cases where TIPHON scenarios will be used. Another concern was with the potential impact on smaller networks/service providers that might face problems obtaining the required MCC or MNCs (Mobile Country Code, Mobile Network Codes). An explanation on the use of IMSI as one of the mechanisms for user identification in TIPHON will be added to DTR-07001. R. Stastny will work with the editor to include the appropriate text. It was suggested that the discussion on user identification issues would benefit from a direct comparison of the functionality provided by using IMSI or by using other mechanisms like NAI. Contributions are invited to elaborate on such a functional comparison. The request to start a new work item investigating the use of smart card technology in TIPHON was not supported.

FURTHER WORK AND DECISIONS ON DTR-07001 In the last session of WG7, it was concluded that DTR-07001 is not yet stable. Further work is needed on the evaluation and recommendation sections. The evaluation matrix of section 6 still lacks material on several mechanisms. Contributions are invited (again) for these sections; a deadline of four weeks after this meeting will apply to these contributions. After this date, sections in the evaluation matrix that have not been populated will be removed from the

document. Further contributions for section 7 of DTR-07001, providing recommendations on mobility for TIPHON based on sections 5 and 6, are required before DTR-07001 can be closed and work on DTS-07003 can start. Therefore, contributions towards section 7 are invited as well. JOINT MEETING OF ITU-T SG11, ETSI SPAN3, AND ETSI TIPHON ON IN FOR VOICE/MULTIMEDIA OVER IP J. Vandenameele (Alcatel) was the chair for this joint meeting. TD-090 is the agenda; TD-121 is the meeting report and liaison statement. Note: ETSI NA and ETSI SPS have been merged into the new TC SPAN. SPS3 has been renamed SPAN3. NA2 has been renamed SPAN2. Objectives of this meeting were to: • Understand the role of IN for TIPHON systems • Prepare a joint action plan for use of IN for Voice (and Multimedia) over IP TD-048 (F. Haerens, SPAN3 Chair) is a liaison from SPAN3. SPAN 3 studied the five TIPHON scenarios. The interaction with IN is shown for each of these scenarios. The liaison proposes that: • The IN infrastructure shall be independent of the IP telephony signaling protocol (SIP, H323, etc.). • The call control and consequently IN control shall be at least at the edge of the network, i.e., nearest to the user in a Local Exchange and between two operators in an Inter-operator Gateway. J. Humphrey (Marconi) presented the current baseline document on the “Requirements for the Functional Architecture for IN support of IP-networks” from SG11 Q5. The material is intended to be included in the IN CS4 baseline document. L. Klostermann (Ericsson and TIPHON WG1 Chair) gave a short introduction to the Back-end Services as currently being defined within TIPHON. They are described in DTR-01002. G. Manor (Vocaltec and Editor for the Back-end Services Architecture) and K. Sambor (Telekom Austria PTA) gave a short presentation of the working document for DTS-02007.

CONCLUSIONS OF THE DISCUSSIONS

The interaction between IN and IP is complex and needs further breakdown. The following interaction scenarios were distinguished: 1. Interworking scenarios covering: • Basic calls • Additional services using BES, the use of IN as a back-end service 2. Integration scenarios with two additional possibilities: • IN controls SCN calls but also assists the IPN • IN also controls the IPN The first priority is Interworking – basic calls: • Scenario 1: IP to SCN + Scenario 3: SCN to IP to SCN; At a minimum, Number-Translation services in the IP network have to inter-work • Scenario 2: SCN to IP + Scenario 4: IP to SCN to IP; At a minimum, Number-Translation services in the SCN network have to inter-work with similar services in IP, with similar services in the SCN • Scenario 0: IP to IP TIPHON will create an Informational Annex in DTS-02003 providing the results of a first analysis of the interworking scenarios identified above.

TIPHON will further develop the use of IN for Back-end Services as part of DTS-02007. It was agreed that ETSI SPAN3 and ITU-T SG11 Q5 will align their work on IN and VoIP with the priority agreed. A second joint meeting will be held during the next TIPHON meeting on October 7 or 8, 1999, with the goal to further analyze the different interworking scenarios and agree on a work split between TIPHON, SPAN3, SPAN6 and Q5/11. SECURITY SESSIONS AT TIPHON 14 M. Shore (Nokia) has been the interim rapporteur for this group and was unanimously appointed as the Special Rapporteur for the security group. TD-134 is the meeting report. S. Thomas (outgoing Special Rapporteur) was thanked for his work as TIPHON Special Rapporteur for Security. There is an ETSI mailing list for discussion of TIPHON-related security issues. To subscribe, send email to [email protected] with in the body of the message. To send messages to the list; send email to [email protected].

LAWFUL INTERCEPT TD-031, a draft of the deliverable DTR-03008, Security: Studies into the Impact of Lawful Interception, on an investigation of lawful intercept for TIPHON, was accepted at the working group level. The work on lawful intercept for TIPHON-compliant systems is to take place in two steps: 1) The document on hand, a study on the impact of user requirements, and 2) The specification of an interception function. A sufficient number of companies supported a new work item covering the second step; S. Cadzow (ETSI STF 114) is drafting the work item. The work will consist of a definition of TIPHON- specific requirements for lawful intercept, and a definition of reference points where the interception can take place. New text will be produced at the September TC SEC meeting. Since this was not a WG meeting, TIPHON was requested to approve DTR-03008 at the project level during the TIPHON 14 meeting.

SECURITY PROFILES TD-056, Digital Signature Security Profile for TIPHON (Telekom Austria, Infonova), presents a new profile intended to provide guarantees of the authenticity and integrity of signaling data and the privacy of the media stream, as well as against the repudiability of the message. A number of issues were raised, including the appropriateness of the use of block cipher algorithms for media streams, and the necessity of the use of a trusted time-stamping authority to provide non- repudiability. TD-091 (Siemens AG) recommends against TIPHON endorsing IMTC Security Profile 1 on a number of grounds, technical and otherwise. It was felt that since SG16 is in the process of defining a new Annex J to H.323, an H.235 profile for SETs, it would be appropriate drop IMTC SP 1 from the deliverable and to wait for the completion of H.323 Annex J for inclusion in TIPHON deliverable DTS-03006. [Rapporteur’s note: Annex J is not a security profile and the ITU-T cannot specify the use of particular security algorithms.] As a result of the discussion of both contributions, it was decided to draft a contribution to SG16 based on the modification of the security profile presented in TD-056. However, since SG16 cannot incorporate specific security profiles into its documents, Telekom Austria was requested to resubmit its proposal (in TD-056) for inclusion of its security profile in DTS-03006 at TIPHON 15. Other contributions on security profiles are encouraged as well.

SECURITY TESTING TD-040, Summary of Security testing for InterOp (ETSI STF 114), requests the creation of a new work item to develop test scenarios for security, to be delivered as a WG6 document. The scenarios would need to be available by the end of 4Q99. There was some discussion of the need for key management and other pieces of security-related infrastructure; it was agreed that H.235 signaling needs to be tested, and not the encryption algorithms, per se.

BOF SESSION ON THREAT ANALYSIS TD-135 is the report of the BOF (Birds of a Feather) session on threat analysis. S. Cadzow (ETSI STF 114) presented an overview of the practice of security threat analysis – how it is conducted, how it is applied, and how responses to analyses are incorporated into systems architectures. The slides from the session are in TD-029. The goal of the BoF is to raise awareness of the necessity for a threat analysis of TIPHON systems, and to solicit contributions for the deliverable. The session opened with a description of the conduct of an analysis, including definitions of threats and perspectives from vendors and operators. The goal of a TIPHON threat analysis is to assess TIPHON’s commercial viability, and to identify measures to ensure the integrity of TIPHON services. The analysis is conducted at the service level; for the purposes of the analysis, the terminal and network type will tend towards traditional telephone networks. It was pointed out that the analysis of TIPHON systems is somewhat different from other analyses developed by ETSI, since TIPHON networks are hybrids of different network types (SCN and IP). The point was also raised that doing a complete threat analysis of the existing TIPHON architecture is impossible, since the current reference points represent the IP network side of the architecture, but not the SCN. Quantitative metrics for measuring the seriousness of particular risks were presented. From the vendor perspective, InterOperable security (both policies and parameters) are mandatory. Threats are classified by asset dependence and network entity location. Back end services are a prime target for attack, as are signaling gateways. From the operator perspective, threats tend to fall into the categories of end-user threats (such as fraud and eavesdropping) and InterOperator threats (such as routing or settlement fraud). The risks to the operator include loss of revenue, image damage, and possible liability for failure to perform. TD-030 is a draft of a new work item, TIPHON Threat Analysis. It lists the objectives of the different participants in a TIPHON system, including customers, service providers, and manufacturers. The TIPHON architecture and protocols may have to change to reflect the outcome of the analysis. There was agreement that this was an excellent start to the deliverable; discussion consisted largely of suggested additions rather than modifications to existing text. In particular, there was considerable interest in broadening the document to cover IP-specific issues. There was interest in preserving TD-078, An Idiot’s Guide to Threat Analysis (S. Cadzow, STF 114), as an ETSI document of some form, but the author (S. Cadzow, ETSI STF 114) felt that creating a new work item at this time might distract from the more pressing work on the threat analysis deliverable; he said that the guide would be reintroduced at a later date.

TIPHON MEETING #14 ROSTER, JULY 19 – 23, 1999, AMSTERDAM, HOLLAND

Helmut Schink, Siemens TIPHON Chair Lucas Klostermann, Ericsson WG1 Chair Jozef Vandenameele, Alcatel WG2 Chair Gur Kimchi, VocalTec WG3 Chair John Horrocks, DTI WG4 Chair Mike Buckley, Lucent WG5 Chair Michael Blaschitz, Telekom Austria/Infonova WG6 Chair Romeo Zwart, AT&T UK WG7 Chair Melinda Shore, Nokia Special Rapporteur for Security Host: AT&T Netherlands

Alcatel Bell Jan Bouwen [email protected] Alcatel Bell Jozef Vandenameele [email protected] Alcatel France Jean-Pierre Albinet [email protected] Alcatel France Gilles Lefevre Alcatel SEL AG Klemens Adler [email protected] Alcatel SEL AG Rainer Muench [email protected] Ascend Comm. Inc. Matt Holdrege [email protected] Ascom Pero Juric Ascom AG Raymond Wu [email protected] AT&T Ayse Dilber [email protected] AT&T Mark Perkins [email protected] AT&T Tankut Turhan [email protected] AT&T Jur Van Ouwekerk AT&T Romeo Zwart [email protected] Bell Atlantic James Baskin Bellcore Chris Celiberti [email protected] BMWi (Reg TP) Theo Metzger [email protected] BT Alex Cruse [email protected] BT Michael Hollier BT Anthony Holmes BT Paul Mylotte Labs [email protected] BT Richard Reynold [email protected] BT Geoff Richmann BT Richard Swale [email protected] BT Graham Travers [email protected] Cable & Wireless Comm. Tony Anvoner [email protected] Cable & Wireless Comm. Paul Rosbotham Certis Peter Fellows Cisco Systems Massimo Lucchina [email protected] Clarent Corporation Jean-Francais Mule Compaq John Hurlbert [email protected] Dept. of Trade & Industry Charles Brookson Deutsche Telekom Ulrich Stradtmann Deutsche Telekom AG Bernd Adams [email protected] Deutsche Telekom Berkom Harald Klaus [email protected] Deutsche Telekom Berkom Ingmar Kliche [email protected] Deutsche Telekom Berkom Thomas Scheerbarth [email protected] Dialogic Telecom Europe Steven Magnell [email protected] DTI John Horrocks [email protected] ENST Bretagne Hossam Afifi Ericsson Joergen Dyst Ericsson Michel Houde [email protected] Ericsson Eurolab Norway Lill Kristiansen [email protected] Ericsson LM Jan Holm [email protected]

Ericsson LM Lucas Klostermann [email protected] ETSI Susanna Kooistra ETSI Laurent Vreck [email protected] ETSI TIPHON STF 114 Andreas Gustke Eurescom GmbH Magnus Krampell [email protected] Finnet Group Markku Laasonen [email protected] Finnet Group Hannu Nikkanen [email protected] Florentijn van Kampen France Telecom/ CNET Gerard Boulay [email protected] France Telecom/ CNET Claude Boulic Fujitsu Fiona Keane [email protected] GRIC Comm., Inc. Richard Brennan [email protected] HEAD acoustic gmbh (Deutsche Frank Kettler Telekom) IAEI (ECI Telecom) Aharon Segev [email protected] Intel Corporation Narjala Bhasker Intelsat Fawad Abbas [email protected] Korea Telecom (KT) Woon Sik Baek KPN Research John Beerends KPN Research Andries P. Hekstra KPN Research Hans Van de Wassenberg [email protected] Lucent Technologies Azfar Aslam Lucent Technologies Mike Buckley [email protected] Lucent Technologies Dan Quinlan Lucent Technologies Paul Sijben [email protected] Lucent Technologies Louise Spergel [email protected] Lucent Technologies Hans van der Veer [email protected] Lucent Tech. EMEA BV John Segers Lucent Technologies UK James Pratt [email protected] Marconi Comm. Ltd Jane Humphrey Marconi Comm. Ltd Philip Mart [email protected] Media One Lab James Dahl [email protected] Motorola Paul Guram [email protected] Motorola Ted Hatala [email protected] Motorola Malik Khan [email protected] Motorola Edgar Martinez [email protected] Motorola Andy Mullan [email protected] Motorola William Schmidt [email protected] Motorola ISG Simon Kang [email protected] NATO C 3 Agency Martin Peake NEC Europe Stefan Gessler [email protected] NEC Tech. (UK) Ltd Simon Binar [email protected] NEC Tech. (UK) Ltd Matteo Gatta Nokia Janne Koistinen [email protected] Nokia Jarno Rajahalme [email protected] Nokia Corp. Marko Suoknuuti [email protected] Nokia Corporation Peeter Pruuden Nokia IP Telephony Maureen Stillman Nokia IP Telephony Inc. Melinda Shore [email protected] Nokia RC Pekka Pessi [email protected] Nortel John Talbot [email protected] Nortel Jerome Voglimacci [email protected] Nortel Fred Howett [email protected] Nortel Networks Kevin Gorey Nuera Communications David Wang [email protected] OeFEG Richard Stastny [email protected] Ofcom Olivier Girard [email protected] Philips BC Frank Derks [email protected]

Qualcomm, France Peter Jackson [email protected] RegTP (BWMi) Reinhard Walter [email protected] Robert Bosch GmbH Joachim Pomy [email protected] Samsung Electronics Fenn John Siemens Ernst Horvath [email protected] Siemens Juha Korpi [email protected] Siemens Helmut Schink [email protected] Siemens AG Harald Kramer Siemens AG Gerald Meyer [email protected] Siemens AG Ulrich Mitreuter [email protected] Siemens AG Klaus Nimphius [email protected] Siemens ATEA Jean-Pierre Urkens Siemens Comm. Ltd Steve Moore [email protected] Siemens Switzerland Rudi Wegmann Sonera Ltd Sampsamatti Tanner [email protected] STF114 ETSI Scott Cadzow Sec [email protected] STF114 ETSI Jan Ellinger [email protected] Telcordia Technologies Jyotin Basrur [email protected] Telcordia Technologies Gary Richenaker Telcordia Technologies Patricia Wu Tele Danmark Niels Knudsen [email protected] Telecom Eireann Allen Collinge Telecoms. Tech. Comm. Kenji Nakashima [email protected] Telecoms. Tech. Comm. Yutaka Saito [email protected] Telefonica de Espana SA Santiago Inigo Martinez [email protected] Telefonica Mario Munoz [email protected] Telekom Austria Andreas Steiner [email protected] Telekom Austria AG Bernhard Handl Telekom Austria AG Klaus Sambor [email protected] Telekom Austria AG Michael Welser [email protected] Telekom Austria/Infonova Michael Blaschitz [email protected] Telekom Austria/Infonova Herwart Wermescher [email protected] Telenor A.S Trond Ulseth Telenor Res. & Dev. Zaw-Sing Su Telkom SA Ltd John Davis Telkom SA Ltd Paul Inglesby Telstra Farzad Safaei Transnexus Jim Dalton TRT Lucent Tech. France Milo Orsic [email protected] Unisys Gerfried Handke [email protected] University of Bristol Alistair Munro Vienna Systems Corp. Donald Fraser [email protected] Vocaltec Comm. Ltd Gur Kimchi [email protected] Vocaltec Comm. Ltd Gadi Manor [email protected] Vocaltec Comm. Ltd Boaz Michaely Wandel & Goltermann Christoph Boelsterli Eskill Ahlin Gustav Bergmann Norihisa Oota Frederico Renon Tony Stephens

The next issue of Communications Standards Review – Telecommunications (Vol. 10 #9) is also scheduled for September 1999.

REPORT OF Q4/15, XDSL NETWORK ACCESS TRANSCEIVERS, AUGUST 2 – 6, 1999, NUREMBURG, GERMANY The scope of Q4 Study Group 15 is the development of Digital Subscriber Line (DSL) related Recommendations. R. Stuart (3Com) is the Rapporteur. This was the first meeting of the Rapporteur group after the June 21-July 2 Geneva Study Group 15 meeting in which six DSL Recommendations were approved. Work is continuing on the future “bis” versions of these Recommendations as well as new Recommendations targeted to be Determined at the April ’00 Study Group meeting and beyond. At the previous SG meeting, it was agreed to begin the “exploratory” work on home phoneline networking (G.pnt) as spectral compatibility with VDSL is of concern. The Q4/15 document numbering system was enhanced to denote U - updated, A - agenda and R - draft Recommendation documents. NG-001 (D. Stuart, Rapporteur) contains the proposed agenda for the meeting. No liaisons and or correspondence were received. The group has maintained an ftp site with electronic copies of all the contributions at ftp://ftp.itu.int/tsg15/sg15/wp1/q4/xxxx/ (password required). NG-004 contains the electronic document procedures.

INTELLECTUAL PROPERTY RIGHTS NG-20r1 (S. Palm, Matsushita Graphic Communication Systems) informs Q4/15 that a General Patent statement to the TSB has been filed, with Patent Policy Option 2. NG-100 (VoCAL Technologies) states that if the ITU includes MCCC (Multiple Concatenated Convolutional Codes) as mandatory in future G.lite-bis and G.dmt-bis transmitters and optional in receivers, that VoCAL will grant a royalty-free license for transmitter implementations and will follow ITU guidelines for non-discriminatory licensing for receiver implementations. G.SHDSL The goal of the G.shdsl session was to close on a number of remaining technical issues in preparation for Determination of the draft text at the April 2000 SG15 meeting. S. Blackwell (Adtran) is editor. The draft text is in NG-R15©, the session agenda is in NG-A15 , and the updated issues list is in NG-U15. NG-R15© (S. Blackwell, Adtran) is the proposed draft G.shdsl text. This was the first time the text had been presented to Q4/15 in Recommendation form. New sections on references and abbreviations had been copied from G.992.1 (G.dmt). Section 9 on the EOC (Embedded Operations Channel) which was approved at the last meeting had been incorporated. Q4/15 accepted the proposed text from the editor as the current draft text. NG-U15 (S. Blackwell, Adtran) is the updated issues list. It was agreed to move the “targeted applications” from the draft Recommendation to the issues list. NG-043, Proposed text for the summary and scope section for G.shdsl (Adtran, Level One), was agreed to be included in the draft text. NG-066 (S. Blackwell, Adtran) is proposed text for the STU-x (SHDSL Transceiver Unit, central office and remote units), user plane protocol and application models. The text was agreed for inclusion in the draft text for G.shdsl.

FUNCTIONAL DETAILS NG-028 (Orckit) proposes the use of constellation shaping for G.shdsl to improve performance. The contribution states that the agreed line code for G.shdsl and constellation shaping are compatible and that about 0.5 - 1 dB is much easier to achieve by this technique than by further enhancement of the coding scheme. Q4/15 agreed to study this topic further.

NG-040 (Conexant) proposes that components from the HDSL2 TC-PAM based line code be adopted for the G.shdsl Recommendation. The proposal includes the scrambler, the one- dimensional rate - trellis encoder with programmable feedforward taps, a generalized version of the PAM mapping, and the Tomlinson-Harashima precoding. These technical items address open issues 9.1 through 9.4 and were agreed by Q4/15 for inclusion in G.shdsl.

INTERFERER COMBINATIONS NG-041 (Adtran and a T1E1.4 consensus) proposes a number of impairment combinations as design objectives for the North American annex of G.shdsl. The impairment combinations were agreed in the development of the PSD masks for G.shdsl.

ACTIVATION NG-042 (Adtran, Level One) suggests that the basic structure of the HDSL2 activation sequence is appropriate for use in G.shdsl. In HDSL2, the physical layer sequence can logically be split into two sections: a preactivation sequence and a core activation sequence. The preactivation sequence, which includes the functions of unit identification, line probing and parameter exchange, should be replaced in G.shdsl with the G.994.1-based preactivation. The HDSL2 core

activation sequence (starting with signal Cr and including the functions of echo canceller and receiver training, timing acquisition and precoder coefficient exchange) may easily be adapted to meet the requirements of G.shdsl activation. NG-042 provides the core activation text for section 6 of G.shdsl, PMD Functional Characteristics; it was agreed.

SPECTRAL ISSUES/PSDS NG-046 (C. Hansen, Excess Bandwidth Corporation) proposes two PSD masks for G.shdsl that address the data rates of 2.048 and 2.312 Mbit/s at a loop reach of 6 kft. The masks use frequencies below 530 kHz to avoid AM (Amplitude Modulation) interference. Due to compatibilities with other xDSL services, this issue will remain under study. NG-058 (L. Humphrey, Nortel Networks) demonstrates with simulations that non-overlapping frequency systems can successfully operate in deployments where NEXT interference is caused by existing overlapped frequency devices. NG-079 (PairGain Technologies) investigates PSD masks for overlapped spectrum operation without introducing more interference into the upstream direction than DSL NEXT (near end cross talk). Two new issues regarding spectrum compatibility with G.992.1 and G.992.2 were agreed. NG-080, SHDSL spectral compatibility with ADSL (F. Van der Putten, Alcatel), proposes that G.shdsl be specified such that the ADSL performance requirements contained in G.992.1 and G.992.2 can still be met in the case where the DSL, ADSL and HDSL disturbers are partially or fully replaced with SHDSL disturbers operating over the same G.996.1 test loop as the ADSL system under consideration. After considerable discussion, Q4/15 agreed to a call for papers concerning spectral compatibility, in particular with G.992.1 and G.992.2. The plan is to close on this issue at the next Rapporteurs meeting (November 1-5, 1999, Nashville, TN). NG-081 (Alcatel) discusses the impact of G.shdsl onto ADSL performance using HDSL2 masks as the model for G.shdsl interference. Using that model and comparing to HDSL, the contribution suggests that G.shdsl may reduce the loop reach of ADSL from 4 to 5 km and proposes a number of new open issues to the G.shdsl issues list. The new open issues were agreed.

LINE PROBE / PREACTIVATION NG-062 (Adtran) introduces various methods for line probing for G.shdsl by partially using G.994.1 (handshake). The procedures in G.994.1 are combined with full bandwidth probe for activation. In addition, NG-062 discusses a fixed power back-off for the line probe. Q4/15 agreed to the following: • G.994.1 shall be used to exchange capabilities and determine whether a line probe is performed

• G.994.1 shall be used to exchange line probe results and select data rates and power levels • G.shdsl shall support a line probe sequence with selectable duration and selectable spectra G.VDSL The G.vdsl meeting agenda is in NG-A11R3 . NG-R11 is a placeholder for the draft text for G.vdsl. NG-U11 contains the updated issues list. S. Palm (Matsushita) is the editor.

SPECTRUM ALLOCATION NG-033 (Orckit) analyzes VDSL performances with universal band allocation. By using conservative assumptions on PSD masks, the contribution suggests that four bands - two for uplink and two for downlink - are sufficient to reach compliance with ETSI requirements (with only minor deviations) and good performances for the ANSI tests. NG-047 (Texas Instruments) presents simulation and test results on interaction between VDSL and ADSL in the same binder. This shows that in the FTTEx configuration, ADSL can degrade VDSL performance. Simulations show that upstream VDSL channels can be severely affected by ADSL NEXT and downstream VDSL channels can be degraded by ADSL FEXT. In the FTTCab configuration, there is potential for interference from VDSL to ADSL. Simulations show that the VDSL PSD must be constrained to low levels below 1.104 MHz in both the upstream and downstream directions to avoid effects on ADSL performance. NG-067R1 , VDSL Simulation for world-wide band allocation (H. Furuno, NEC), presents the results of simulation using requirements from ANSI, ETSI and those presented in D.514 (NTT, SG15 June-July 1999, see report in this issue of CSR), VDSL co-existing with TCM-ISDN. NG- 067R1 concludes that the band above 10 MHz is necessary to meet the requirements noted in D.514 and that at least seven bands are necessary. NG-068, Spectrum Flexibility - Case 1: Bitstream Access (M. Isaksson, Telia AB), investigates the technical impact bitstream access has on spectral management. It concludes that a fixed spectrum allocation leads to a substantial capacity waste. NG-069, Spectrum Flexibility - Case 2: Direct Access (M. Isaksson, Telia AB), investigates the technical impact direct access has on spectral management. It concludes that a flexible spectrum allocation is preferred. NG-070, Results regarding symmetrical capacity and number of VDSL frequency bands (Telia AB), investigates the capacity efficiency of providing symmetrical VDSL service; it recommends that a programmable frequency mask of at least five bands on a regional basis be adopted. NG-075 (T. Pollet, Alcatel) investigates the technical feasibility of a universal frequency plan. Alcatel chose 16 separate frequency bands and, via an exhaustive search, attempted to find a plan that best met the universal plan requirements. The contribution concludes that a “regional universal” plan is not possible; however, dropping the requirements for the short asymmetric service results in a regional plan that yields a loop reach reduction that affects only 10-20% of the remaining services. Additionally, NG-075 suggests that separate plans for asymmetric and symmetric services and FTTEx (Fiber to the exchange) and FTTCab (Fiber to the cabinet) scenarios be investigated. NG-076r1 (Texas Instruments, SK Telekom, NEC-Japan, Toshiba, Mitsubishi, ST Microelectronics, Nortel Networks) studies frequency plans to address the issues and questions raised in the Geneva ad hoc report TD-043(WP1/15) (see report in this issue of CSR). To meet robustness (bridge taps, radio ingress) and universal duplexing, NG-076r1 finds that at least seven separate bands are necessary and that the specification of a universal plan is possible that nearly meets the ad hoc requirements. NG-093 (Broadcom, General Instrument) discusses the desirability of separate spectral plans for symmetric and asymmetric service. It proposes separate symmetric and asymmetric spectrum plans. Discussion followed concerning the compatibility of two spectrum plans residing simultaneously in the same network.

NG-094 (Broadcom, General Instrument) illustrates that a two-band frequency plan is optimal for asymmetric service and that symmetric service may be accommodated using an additional upstream band. Due to the number of requirements placed upon frequency plan development, a single universal plan may not be feasible. As a solution, NG-104 (Siemens AG) proposes that a small number of frequency plans be developed that are optimized for certain functional requirements and that allow regional standard bodies to specify the appropriate plan for their regions. NG-112R2 (Alcatel, ST Microelectronics, Texas Instruments, Mitel) proposes a universal frequency band for VDSL. The universal plan was derived from the commonalities of the European and North American requirements for both FTTEx and FTTCab requirements as well as co-existence of asymmetric and symmetric services in the same cable bundle. NG-116R1 (Alcatel) investigates a spectral plan for VDSL that does not utilize the ADSL frequencies. Based on the metric defined in NG-075, it defines a spectral plan for North America and ETSI using six and five frequency bands, respectively. Significant agreements were reached from general discussion and the ad hoc report (NG-114R1 ): • VDSL systems shall be able to deliver asymmetric and symmetric bitrates in the same cable binder. • The performance penalties due to coexistence of asymmetric and symmetric services shall be fairly shared.

FILTERED MULTITONE (FMT) NG-056 (IBM) reviews the concept of equivalence theory for QAM (Quadrature Amplitude Modulation) and multitone signals by constructing both from a set of filterbank elements. NG-063, FMT, compromise solution towards a single physical-layer standard for VDSL (IBM, GlobeSpan, AltoCom), summarizes the advantages of FMT modulation as previously presented in D.649 (from the SG15 meeting, see report in this issue of CSR). NG-064 (IBM, GlobeSpan, AltoCom) illustrates the trade-off in complexity between filterbank modulation system vs. a single-band system in terms of operations per second required for channel equalization. NG-064 concludes that, including the extra demodulation complexity for filterbank de-/modulation, the total complexity of a filterbank system is not more complex than a single-band system. NG-088 (AltoCom) outlines a hardware/software architectural approach for VDSL transceiver based upon FMT. It was offered as a compromise position for the VDSL line code and was presented for information only.

G.PNT-RELATED NG-085 (AMD, GTE Government Systems, IBM, Intel, Samsung, SK Telekom, Texas instruments, presented by J. Cioffi, Stanford) reports on use of iterative decoding to mitigate the effect of Home-LANs on VDSL; it is a follow-up from MA-033 (March 31, 1999, Melbourne, see CSR Vol. 10.4) which showed that iterative decoding could be used to mitigate interference from Home LAN devices on VDSL, albeit with significant computational complexity. NG-085 outlines a reduced complexity method of iterative decoding performed by the VDSL receiver that obtains almost the same performance as the optimal solution. Partial band silencing and insertion of flow density random parity checks in either or both signals is found to assist the simplification of the joint detector. The complexity has been reduced to be around the equivalent to a VDSL DMT demodulation.

REGIONAL SPECIFIC NG-038 (Mitsubishi) presents a performance simulation of the effect on VDSL of TDD boost below 1.1 MHz. It identifies that TDD boost below 1.1 MHz is most effective to increase bitrate performance of VDSL in an environment co-existing with TCM-ISDN.

POWER BACK OFF (PBO) NG-048 (Texas Instruments) demonstrates via simulations that power back-off affects the achievable bitrates in any chosen frequency plan and thus points to the need for considering power back-off when evaluating candidate frequency plans. NG-049 (Texas Instruments) proposes that Q4/15 agree on a specific back-off method, which should be implemented autonomously, by the VTU-Rs to ensure harmonious operation in unbundled environments. NG-050 (Texas Instruments) examines the effect of the number of upstream bands on the performance of upstream power backoff. This contribution points out that use of many upstream bands with constant power back-off provides a better approximation of spectrally shaped transmit PSDs than use of a small number of bands.

RFI/EGRESS NG-086 (Alcatel) presents bench test measurement results of the robustness of DMT VDSL to amateur radio interference. The results show that a multi-carrier system can cancel non- stationary AM modulated RFI as high as -20 dBm on a 1 km loop without margin loss and bit errors. This contribution was presented for information only. NG-087 (Alcatel) studies the feasibility of VDSL transceivers to respect a notched spectrum to reduce the effect of unwanted radiated emissions from VDSL. Both linear filtering and windowing are considered to create notches in the spectral mask and for frequency band separation. It concludes that both techniques can be used. However the use of a temporal window seems to be an elegant, low complexity method. NG-096 (Alcatel) proposes a number of agreements related to egress control. Q4/15 agreed to: • Require a G.vdsl unit to reduce the PSD simultaneously to below –80 dBm/Hz in one or more of the standardized amateur radio bands • Require that G.vdsl modems shall meet the requirements on performance under conditions representative where a VDSL unit is susceptible to RF ingress from non-stationary amateur radio signals • Adopt text from ETSI VDSL specification for the model of Amateur RF noise (section 9.3.8) as presented in D.535©, SG15 June-July, 1999 into the draft G.vdsl text.

SPECIFIC G.VDSL TEXT NG-021 (S. Abbas, Centillium Technology) contains proposals related to Forward Error Correction definition and parameters. Q4/15 agreed to a byte-oriented Reed Solomon code in both the upstream and downstream direction. Q4/15 agreed to a Reed Solomon polynomial and code word for G.vdsl (same as in G.992.1 and G.992.2). Q4/15 agreed to support an R value from 2 to 16. NG-022 (S. Abbas, Centillium Technology) contains proposals related to the interleaver definition and parameters. Q4/15 agreed to include the Convolutional interleaver as defined in NG-022 for both the upstream and downstream direction for the slow/interleaved channel. NG-023 (S. Abbas, Centillium Technology) contains proposed text and definition of a scrambler for G.vdsl. Q4/15 agreed to include the scrambler as defined in NG-023 and to include the text from the Annex with the understanding that some additional editing of the text will be necessary. NG-044R1 (S. Palm, Matsushita) proposes text for a top-level table of contents. It was agreed as the draft table of contents. NG-051, Transmission Convergence (TC) Sublayer Reference Model and Interface Specification (Lucent, Bosch Telekom, Broadcom Corporation, GlobeSpan, General Instruments, Newbridge, Nokia, Samsung, Siemens AG, Tellabs Oy, US West), proposes a generic partitioning of the draft G.vdsl by way of a gamma, alpha-beta and PMD interface. It also proposes that G.vdsl support optional single and dual latency modes, a multi-service architecture, and only a single clear

operation channel using single latency with interleaving. The PMD layer should contain framing, randomization, error correction and interleaving. After an ad hoc meeting (report in NG-114R1 ), Q4/15 agreed to the following: • The TC shall optionally support a multi-service architecture (e.g., ATM, STM, IP, etc.) with the appropriate TPS-TC (Transport Protocol Specific - Transmission Convergence) sublayer. • For each applied transport protocol, a specific TPS-TC shall be defined. Each application path is originated and terminated by a corresponding pair of TPS-TC at the opposite sides of the link. The TPS-TC OC (Operation Channel) shall provide a clear EOC. NG-052 (Lucent, Analog Devices, Bosch Telekom, Broadcom, GlobeSpan, General Instruments, Newbridge, Nokia, Samsung, Siemens AG, Tellabs Oy, US West, Alcatel, Aware, Ericsson, Mitel, NEC America, NEC Japan, Nortel, Rockwell, Samsung AIT, ST Microelectronics, Telia, Texas Instruments) proposes text for the ATM TC definition in the G.vdsl text. Q4/15 agreed to incorporate the text as provisional. ADC / AFE NG-055 (Texas Instruments) investigates the number of bits needed in the AFE (Analog Front End) for DMT VDSL. It concludes that 12 bits are necessary for full featured DMT VDSL. NG-059 (Broadcom) concludes that 6-8 dB of effective bits are lost in a digital duplexed AFE for VDSL on long loops. Analog filtering is needed for high performance VDSL; hence a fixed frequency plan should be developed. NG-065 (IBM) illustrates that a multicarrier modulation can meet the ETSI and ANSI PSD spectral masks by notching certain frequency bands, whereas a single-carrier system would allegedly require complex variable or switchable filter sections to meet the identical PSD mask requirements. NG-071 (Alcatel, IBM Research, Mitel Corporation, ST Microelectronics, Texas Instruments, Toshiba) studies the number of bits required at the ADC (Analog to Digital Converter) for DMT VDSL. The implementation issues were investigated; the conclusion of the contributing companies is that a 12-bit Analog to Digital conversion at 35 MHz is feasible. NG-072 (Telia AB, ST Microelectronics) investigates quantization noise mitigation issues for digitally duplexed DMT VDSL using oversampling, range optimization of the ADC and DAC, clip-noise shaper, de-emphasis/pre-emphasis filtering and non-uniform quantization. It concludes that the full 12 bit effective performance of the ADC can be recovered by the techniques outlined in the contribution.

COMPLEXITY NG-091 (Mitel, ST Microelectronics, Texas Instruments, Toshiba) states that due to advances in semiconductor technology, interoperable DMT VDSL devices can be available within one year. NG-105r1 (Siemens AG) compares the dies sizes at .35 and .15 µm geometries for SCM- and DMT-based implementations. It estimates that the SCM-based implementation would have a chip area four times smaller than an equivalent DMT-based implementation. It points out that chip area has significant implications for chip implementations.

LINE CODE SELECTION NG-036 (S. Abbas, Centillium Technology) suggests that consensus be reached within the group for a single line code for G.vdsl and that the group not rush to any decision on the line code issue without due diligence on all the line code proposals. NG-053 (BT, Deutsche Telekom Group, France Telecom, GTE, Korea Telecom, KPN, Stentor Canadian Network Management, Swisscom, Telecom Italia Group, Telia, US West, Alcatel, Analog Devices, Bosch Telecom, Broadcom Corporation, Ericsson, Fujitsu [Japan] Ltd., General Instrument/NLC, GlobeSpan Technologies, Lucent Technologies, Mitsubishi Electric Corporation, NEC-America, NEC-Japan, Newbridge Networks, Nokia Corporation, Nortel Networks,

Samsung Electronics, Siemens, SK Telecom, ST Microelectronics, Tellabs Oy, and Toshiba) proposes that Q4/15 develop a standard that includes the definition of two line codes. After much discussion and a straw poll of the group, consensus on a dual line code standard for VDSL could not be reached. NG-074 (Alcatel, Aware, Ericsson, ETRI, IBM, Italtel, Integrated Telecom Express [ITeX], Mitel Corporation, Mitsubishi Electric Corporation, NEC America, NEC Japan, Nortel Networks, Samsung, SK Telecom, ST Microelectronics, Telia AB, Texas Instruments, Toshiba) proposes that DMT be selected as the line code for VDSL. NG-092 (Texas Instruments) compares the complexity of a DMT and QAM based VDSL device. It concludes that the flexibility of DMT makes DMT the correct choice for a VDSL line code. Q4/15 spent some time working on line code selection. Some participants stated that a line code selection was necessary to move the work forward. The editor proposed that Q4/15 should work towards a line code selection at the next meeting in Nashville, Nov. 1-5. Others noted that sufficient analysis was not available to allow a line code to be selected soon. G.HS-BIS Two subjects received attention in this session: the concept of supporting multiple xTU-Rs over the same customer premise wiring, and power cut back. L. Brown (Motorola) is editor. The updated issues list is in NG-U16. G.hs (G.994.1) was Decided (approved) at the June-July meeting of SG15. NG-106 (3Com) proposes that multiple ATU-Rs be supported on the same in-home wiring plant using the ANSam concept of V.8. It also proposes for G.hs-bis, that the C-TONES signal be AM modulated once a reply from the customer premise has been received by the CO, to signal a “busy” state of the G.hs protocol and thereby regulate G.hs-bis transceivers during the session establishment phase of initialization. Without this mechanism, two G.lite modems would not be able to coexist on the same premise wiring and independently communicate to the ATU-C. A new open issue was agreed to be added to the issues list. NG-103 (S. Palm, Matsushita) investigates using existing G.hs signals to initiate and signal the power back-off parameters. The proposal is a further development of the general use of G.hs for power back-off presented in NG-062 (see discussion under G.shdsl, above). Q4/15 agreed that the deadline for proposals for a line probing procedure shall be the November 1999 meeting and that an agreement on the procedure shall be made at that time. G.PNT This is the first Rapporteur meeting in which home networking was addressed by Q4/15. The rationale for studying this topic in Q4/15 is the need for spectral compatibility with VDSL systems that may use a common frequency band. The issues list is in NG-U12R4 . J. Magill (Lucent) is editor. R. Hamdi (Compaq) substituted as editor at this meeting as J. Magill was not present. NG-101 (from the HomePNA as sourced by 3Com, Alcatel, AMD, Broadcom, Compaq, HP, IBM, Intel, Lucent, Motorola, Texas Instruments) presents simulations and measurement results of home phone wire transmission characteristics; it concludes that moving home phoneline networking above 10 MHz is not practical. NG-102 (HomePNA, sourced by 3Com, Alcatel, AMD, Broadcom, Compaq, Conexant, HP, IBM, Intel, Lucent, Motorola, Texas Instruments) addresses G.pnt and G.vdsl compatibility. The source companies recommend that a “compromise PSD spectral mask” be used for G.pnt. With the compromise mask, G.pnt/G.vdsl crosstalk is mitigated and the RFI to/from radio bands is addressed. The maximum PSD level of the compromise mask is -73.5 dBm/Hz in the 4-10 MHz band. The source companies recommend that this G.pnt mask should not be further compromised to avoid degraded performance on “challenging,” in-premise networks, and to allow for increases in G.pnt data rates beyond 10 MHz in the future. VDSL performance is presented in the

August-B 1999 Vol. 10.8 Copyright © CSR 1999 73 COMMUNICATIONS STANDARDS REVIEW presence of G.pnt disturbers both with and without VDSL self-disturbers. The results indicate that a solution to the cross-talk issue with overlapping G.pnt/G.vdsl spectrum should be practical. NG-45r1 (M. Tzannes, Aware) proposes G.vdsl and G.pnt compatibility through detection of the G.pnt interferer by magnetic signal coupling in the VDSL device. The contribution also proposes that the G.pnt disturber be commanded by the VDSL system to reduce power if significant G.pnt interference is detected. NG-109 (AMD, Broadcom, Compaq, Lucent, TI) proposes that G.pnt systems be able to reduce the emitted power in the standardized Amateur Radio bands to below -80 dBm/Hz. A number of joint meetings with TR-30.1 have been scheduled to progress the work of G.pnt. NG-110 contains a schedule of all meetings pertaining to G.pnt up to March 2000. (See CSR Calendar on the back page of this issue.) Q4/15 agreed in principle that for the next two meetings contributions should primarily address spectral compatibility of G.pnt system operation below 10 MHz as a goal of G.pnt operation. An ad hoc group chaired by R. Hamdi (Compaq) was convened to address the details of test parameters that should be used for spectrum compatibility of crosstalk analysis of G.vdsl and G.pnt systems. The ad hoc report is in NG-118R1 . The following agreements were reached: 1. All test parameters should be provided by Q4/15 Quebec City meeting on August 20. 2. Both G.pnt and G.vdsl PSD models will be exchanged. PSD shall be described via a representative mask of worst case average power (0-30 MHz), with an as-yet-unspecified short-term averaging window assuming constant transmission. 3. Analyses should be based on the cable crosstalk models specified in MA-055. The noise summing model specified in the ANSI Spectrum Management Standard should be used. 4. Contributions NG-041 or NG-112R2 may be used for VDSL PSD masks. 5. For evaluation, a proposed PSD mask should be provided for G.pnt system operating in the frequency range of 4-10 Mhz with notches in the amateur frequency bands. 6. Note that in the case of G.pnt, power at the subscriber loop is reduced by at least 3 dB from transmitter power levels, and noise ingress from the subscriber loop is similarly reduced by at least 3 dB. 7. G.vdsl loop lengths of 1000 ft. (24 & 26 AWG), 3000 ft. (24 & 26 AWG), 1200 meters (24 & 26 AWG), 4500 ft. (24 AWG) should be used. A set of three G.pnt channel models should be provided. 8. For both systems, self-only and foreign-only disturbers should be simulated. The number of PNT disturbers should be 0, 1, 10. The maximum number of VDSL disturbers should be 20. 9. Results should be reported as maximum channel capacity (Mbit/s) with an assumed 6 dB margin for G.vdsl and 0 dB margin for G.pnt. 10. For simulating VDSL systems, the point of injection for PNT crosstalk should be 30 ft. from the VDSL line termination downstream, and 300 ft. from the ONU upstream. G.LITE-BIS The editor for G.lite-bis is T. Cole (AMD). The agenda is in NG-A18 ; the updated issues list is in NG-U18. NG-113 (Nortel) informs Q4/15 of the efforts of the ADSL Forum on interoperability. The ADSL Forum anticipates close cooperation between the ADSL Forum and the ITU to improve upon the G.992.1 and G.992.2 Recommendations and invites participation of all ADSL Forum members.

PERFORMANCE GOAL OBJECTIVES NG-034 (Ameritech) proposes that G.dmt-bis and G.lite-bis require 512 kbit/s downstream and 160 kbit/s upstream net data rate for all unloaded loops in the presence of self crosstalk (crosstalk from the identical DSL) and HDSL NEXT and FEXT (Near and Far End Cross Talk). NG-034 additionally proposes that G.lite-bis be targeted for Determination in April 2000. Q4/15 agreed, as a primary objective of the work, to maximize loop reach for the 512k/160kbit/s case.

VOICE OVER DSL NG-025 (S. Abbas, Centillium) reviews a number of ways voice can be supported over G.lite. It describes a simple approach to support 64 kbit/s channels over G.lite-bis using a separate voice transport TC that takes major responsibility for voice processing with least impact on the PMS- TC or PMD layers. It proposes studying an embedded voice support for G.lite-bis.

PERFORMANCE IMPROVEMENT METHODS NG-061 (Silicon Automation Systems) discusses the advantages of frame-based transport mechanisms over cell-based transport mechanisms, especially for the G.lite modems, and suggests FUNI (Frame-based User Network Interface) as a better option than cell-based services (e.g., ATM) for the access portion of the network.

FAST RETRAIN NG-081 (Alcatel) discusses the impact of G.shdsl on ADSL performance using HDSL2 masks as the model for G.shdsl interference. Using that model and comparing to HDSL, it suggests that G.shdsl may reduce the loop reach of ADSL from 4 (HDSL2) to 5 km (HDSL). NG-081 points out that interference specifically into tone 64 - the pilot - during initialization causes reduced performance of G.lite. NG-107 (3Com) proposes that G.lite-bis include functionality to modify a profile during profile selection in Fast Retrain. Because of the dynamic nature of the splitterless twisted pair channel, either the existing profiles may become obsolete or there may be insufficient capability to store all the profiles required. NG-107 suggests that a mechanism be added to the fast retrain procedure to allow modification of existing profiles so that they may be tailored to the current channel conditions. This was added as an open issue to the issues list.

EXTENDED PSD MASK OPTION NG-032 (NEC-USA) examines the additional loop reach and bitrate that can be achieved by utilizing the frequency band below 25 kHz for ADSL transmission. By extending the flat G.lite PSD mask over the voice-band below 25 kHz, it is estimated that the link rate can be increased in the range of 80-200 kbit/s for G.lite test case loops. The extra bandwidth may also be used to increase the downstream data-rate and loop reach by adjusting the FDD band-split frequency.

QUIESCENT MODE NG-083 (Paradyne) analyzes the impairments of combined cross-talk from multiple short-term stationary and continuous disturbers. The results show that crosstalk estimation can be performed with acceptable measurement tolerance, time and complexity limits for combinations of continuous and short term stationary disturbers with duty cycles as low as 0.1%. NG-030 (Nortel Networks) proposes additional tests for G.992.2 to address ingress RFI noise (based on AM radio transmitters) in the North American environment. The proposal also includes changes to the ETSI-A noise model for the European environment. An open issue was added to the issues list.

G.992.2 IMPLEMENTERS GUIDE NG-115 (Alcatel, Nortel, Aware, AMD, Intel, Texas Instruments, Compaq, IteX, Centillium) points out an error in G.992.2 in the text in the definition of C-MEDLEY. The text, “and 512 bits are used for each symbol,” appears to have been deleted. The group agreed that the current text is in error and agreed to take appropriate action via an implementor’s guide or other means.

OTHER HIGHLIGHTS NG-060 (Silicon Automation Systems) proposes that the group delay specification in G.lite be reduced from 50 microseconds to 25 (15 microseconds for the ATU-C non-overlapped spectrum operation) to reduce the complexity of the equalizer. An open issue was added to the issues list.

Papers were requested on: • Performance improvement methods • Application/service requirements • Constellation-related issues to improve performance G.DMT-BIS The work program for G.dmt-bis is in NG-A17. F. Van der Putten (Alcatel) is editor. The work program includes both the revision of G.992.1 and the development of an amendment containing a new appendix H addressing requirements for an SDSL system operating in the same binder as ISDN. NG-U17R5 is the issues list for G.dmt-bis. NG-034 (T. Starr, Ameritech) proposes that G.dmt-bis and G.lite-bis require 512 kbit/s downstream and 160 kbit/s upstream net data rate for all unloaded loops in the presence of self crosstalk (crosstalk from the identical DSL) and HDSL NEXT and FEXT (Near and Far End Cross Talk). No agreement was reached concerning maximizing loop reach at the 512k/160k bitrate case as in G.lite-bis. Two new test loops of an as-yet-undetermined length were agreed at the rates of 512k/128k and 640k/256k (issues 3.5 and 3.6). NG-103 (S. Palm, Matsushita) investigates using existing G.hs signals to initiate and signal the power back-off parameters. The proposal is a further development of the general use of G.hs for power back-off presented in NG-062 (see discussion under G.shdsl, above). NG-097 (VoCAL Technologies) presents the power penalty of Reed Solomon FEC codes while investigating the coding gain provided by combinations of MCCC (Multiple Concatenated Convolutional Codes), Reed-Solomon and Trellis coding. NG-027 (Orckit) discusses the impact of decision errors on the performance of the timing recovery circuits when using a data-directed timing recovery. It is shown that the performance of such a timing recovery algorithm may improve on the pilot-based timing recovery. The proposed functionality also eliminates the need for pilot reallocation in the presence of single frequency noise. This new functionality was agreed. NG-054 (K. Barman, Silicon Automation Systems) proposes to shift the downstream pilot tone to one or more sub-carriers during “SHOWTIME.” Shifting the pilot tone to a low SNR sub-carrier increases the data rate significantly for longer loops; reallocation of the pilot tone to more than one low SNR sub-carrier, where bits cannot be allocated, makes pilot recovery more reliable. NG-057 (Silicon Automation Systems) proposes the use of 1 bit constellations for increased loop reach and PAR (Peak to Average Ratio) reduction. It was added to the open issues list for G.dmt- bis and G.lite-bis. NG-039 (PC-Tel) proposes parallel transmission of one or more bits of information on several DMT tones, whose SNRs are too low to be individually used for even minimum bit/tone transmission. A receiver coherently combines the tones, bearing the same information, to achieve a final SNR (Signal to Noise Ratio) sufficient for desired BER (Bit Error Rate). This topic was added to the open issues list for G.dmt-bis and G.lite-bis; this issue is expected to be closed at the November meeting. Q4/15 agreed that G.dmt-bis will include a test loop for 512k/160k. They also agreed that robustness of the single frequency initialization signals shall be addressed. Detailed agreements can be found in NG-U17R5 , the updated G.dmt-bis issues list. Call for papers was made in the areas of: • Constellation details needed to implement the NG-057 and NG-039 proposals. • MCCC details • RFI threat models G.REF-BIS The updated issues list is in NG-U14. The editor for this work is S. Abbas (Centillium).

NG-037 (Centillium) proposes to use the terminology “PMD sub-layer” (Physical Media Dependent) instead of “Transceiver” for consistency between the old and new Recommendations in G.ref-bis. This was accepted. G.TEST-BIS The updated issues list is in NG-U13. The editor for this work is M. Tzannes (Aware). NG-030 (Nortel) recommends that G.test-bis include a description and a test for RFI threats into G.992.2. It also recommends working on the equivalent for G.992.1 and G.shdsl. The group decided to investigate this issue and defer this decision to a future meeting.

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Communications Standards Review regularly covers the following committee meetings:

TIA TR-29 Facsimile Systems & Equipment TR-30 Data Transmission Systems & Equipment TR-41 User Premises Telephone Equipment Requirements TR-42 User Premises Telecommunications Infrastructure ITU-T SG8 Telematic Terminals SG15 WP1 Network Access SG15 WP2 Network Signal Processing SG16 Multimedia ETSI ATA Analog Terminal Access DTA Digital Terminal Access TIPHON Voice over Internet TM6 Transmission & Multiplexing

ACRONYM DEFINITIONS 3GPP Third Generation Partnership Project A/D Analog to Digital ACELP Adaptive CELP ADC Analog to Digital Converter ADPCM Adaptive Differential PCM ADSL Asymmetric Digital Subscriber Line AFE Analog Front End ALC Automatic Level Control ALCE Automatic Level Control Equipment AM Amplitude Modulation ANSI American Nat’l Standards Institute ANT Access Network Transport (Q1/15) API Application Programming Interface ATM Asynchronous Transfer Mode ATU-C ADSL Transceiver Unit - near CO ATU-R ADSL Transceiver Unit - Remote Terminal AWG American Wire Gauge BCH Bose, Chaudhuri, and Hocquengham BER Bit Error Rate BES Back-End Services CAP Carrier-less Amplitude modulation Phase modulation CELP Code Excited Linear Prediction CENELEC Commission Europeenne de Normalisation Electrotechnique (European Electrotechnical Standards Committee) CLI Calling Line Identification CM Call Menu CME Circuit Multiplication Equipment CO Central Office CoIP Conferencing over IP (IMTC Activity Group) CS-ACELP Conjugate Structure ACELP DAC Digital to Analog Converter DCME Digital Circuit Multiplication Eqpt. DLC Digital Loop Carrier DMT Discrete Multi-tone DSI Digital Speech Interpolation DSL Digital Subscriber Line DSS1 Digital Subscriber Signaling 1 DTE Data Terminal Equipment DTMF Dual Tone Multi Frequency DTR Draft Technical Report DTS Draft Technical Standard (ETSI) EC Echo Control ECE Echo Control Equipment EDGE Enhanced Data rates for GSM Evolution EDH Electronic Document Handling EIA Electronic Industry Alliance ENUM IETF’s tElephone NUmbering Mapping EOC Embedded Operations Channel EP ETSI Project ETSI European Telecommunications Standards Institute FDD Frequency Division Duplexing FEC Forward Error Control FEXT Far End Cross Talk FFT Fast Fourier Transform FMT Filtered MultiTone FO Fiber Optic (TIA) FTTCab Fiber to the cabinet

FTTEx Fiber to the exchange GII Global Information Infrastructure GK GateKeeper GPRS General Packet Ratio Service GSM Global System for Mobile Communications GSTN General Switched Telephone Network (e.g., PSTN) GW GateWay HDSL High-rate Digital Subscriber Line HFC Hybrid Fiber Coax HFCI H.323 Firewall Control Interface HomePNA Home Phoneline Networking Alliance ICANN Internet Corporation for Assigned Names and Numbers ID Identification IDL Interface Design Language IEC International Electrotechnical Committee IEEE Institute of Electrical and Electronic Engineers IETF Internet Engineering Task Force IMSI International Mobile Station Identity IMTC International Multimedia Teleconferencing Consortium IN Intelligent Networking INAP Intelligent Network Application Profile IP Internet Protocol IPN Intelligent Packet Network IPR Intellectual Property Rights IPT Internet Protocol Telephony IREG ITU-T Recommendation Experiment Group ISDN Integrated Services Digital Network ISO Int’l Organization for Standardization ISUP ISDN User Part ITU International Telecommunication Union ITU-R ITU Radiocommunications Sector ITU-T ITU Telecommunications Sector JM Joint Menu JTC Joint Technical Committee LAN Local Area Network LDCELP Low Delay CELP MCCC Multiple Concatenated Convolutional Codes MCM Multi-Carrier Modulation MDI Medium Dependent Interface Megaco Media gateway control MG Media Gateway MGC Media Gateway Controller MGCP Media Gateway Control Protocol MOS Mean Opinion Score MoU Memorandum of Understanding NA Network Aspects (ETSI TC) NAI Network Access Identifier (RFC 2468) NAR Numbering, Addressing and Routing Committee of ETSI NA2 NEXT Near End Cross Talk NLP Non-Linear Processor NNI Network to Network Interface NSF Non-Standard Facilities OA&M Operations, Administration, and Maintenance ONT Optical Network Terminal ONU Optical Network Unit OSP Open Settlement Protocol PAM Pulse Amplitude Modulation PAR Peak to Average Ratio

PBX Private Branch Exchange PC Personal Computer PCC Per Call Control PDH Primary Digital Hierachy PICS Protocol Implementation Conformance Statement PINT PSTN Interworking (IETF) PMC Packet Mode Channel PMD Physical Media Dependent Layer PNT Phone-line Network Transceiver PON Passive Optical Network POTS Plain Old Telephone Service PSD Power Spectral Density PSTN Public Switched Telephone Network QAM Quadrature Amplitude Modulation QoS Quality of Service QSIG The signaling protocol used at the Q-interface between two switches in a private network. ECMA/ISO have defined a set of QSIG standards. RF Radio Frequency RFC Designation for an IETF Standard RFI Radio Frequency Interference ROAMOPS Roaming Operations Task Force RSVP Resource Reservation Setup Protocol (IETF) RTP Real Time Transport Protocol (IETF) RTR Revised Technical Report (ETSI) RTS Revised Technical Specification (ETSI) SBID Stuff Bit ID SCF Service Control Function SCM Single-Carrier Modulation SCN Switched Circuit Network SCTE Society of Cable Television Engineers SDL Specification and Description Language SDSL Symmetrical high bit rate Digital Subscriber Line SEC ETSI Security Technical Committee SG Study Group (ITU) SHDSL Single-line High Speed DSL SIP Session Initiation Protocol (IETF) S/N Signal-to-Noise SNMP Simple Network Management Protocol SNR Signal to Noise Ratio SPAN Services and Protocols for Advanced Networks (ETSI Committee) SPNE Signal Processing Network Equipment SRF Service Resource Function SS7 Signaling System 7 SSF Service Switching Function STF Specialist Task Force STM Synchronous Transmission Mode TC Transmission Convergence Layer TCM Time Compression Multiplex TCP Transmission Control Protocol TDD Time Division Duplexing TDM Time Division Multiplexing TIA Telecommunications Industry Association TIGIN Transport Network Equipment for Interconnecting GSTN and IP Networks TIPHON Telecommunications and Internet Protocol Harmonization Over Networks (ETSI Project) TIPIA TIPHON IP telephony Implementation Agreement TMN Telecommunications Management Network TPS Transport Protocol Specific TR Technical Report

TS Technical Specification TSB Telecommunications Standardization Board (ITU) UDP User Datagram Protocol (IETF) UMTS Universal Mobile Telecommunications System UNI User-Network Interface UPT Universal Personal Telecommunications (ITU) UTRAN UMTS Radio Access Network VAME Voice on ATM Multiplication Equipment VBD Voice Band Data VDSL Very high speed DSL VoIP Voice Over Internet Protocol VON Voice on Network Coalition VTU-O VDSL Transeiver Unit at the Optical network unit VTU-R VDSL Transceiver Unit - Remote Terminal WG Working Group WI Work Item WP Working Party (ITU) WTSA World Telecommuncations Standardization Assembly (ITU) xDSL all the different Digital Subscriber Line equipment XID eXchange IDentification xTU-C All the different Transceiver Units - near CO xTU-R All the different Transceiver Units - Remote terminal

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1999 STANDARDS COMMITTEE MEETING SCHEDULES AS OF AUGUST 20, 1999 Subject to Change without Notice

Committee Date(s) Location Committee Date(s) Location TR-29 Aug 9 - 11 Monterey, CA Q 5-7, 21/15 Rapp Oct 4 - 8 Washington, DC TR-30, note 1 Aug 16 - 19* Quebec City, PQ TR-30, note 2 Oct 11 - 15*, Baltimore, MD Q4/15 G.pnt Aug 20 Quebec City, PQ ETSI ATA Oct 11 - 15 Vienna, Austria TR-41 and TR-42 Aug 16 - 20 Ottawa, Ont Q11-15/16 Rapp Oct 18 - 22 New Jersey Q16-17/16 Rapp. Aug 25 - 27 Geneva ETSI DTA Oct 26 - 28 S. Antipolis, FR T1E1 Aug 23 - 27* Baltimore, MD Q4/15 Rapp. Nov 1 - 5 Nashville, TN Q5/8 Rapp. Aug- Sep Japan TR-29 (proposed) Nov 2 - 4 Southeast US Q4, Q8, Q23/16 Sep 13 - 17 Belgium TR-41 and TR-42 Nov 8 - 12 Reno, NV Q1/8 , Q4/8 Rapp, Sep 20 - 24 Maidenhead, UK TR-30, Note 3 Nov29-Dec3* Clearwater, FL SG8 Limited Q4/15 G.pnt Dec. 1 (PM) Clearwater, FL Task Plenary ETSI TM6 Nov29-Dec 3 Amsterdam, NL ETSI TM6 Sep 20 - 24 Edinburgh, UK TIPHON 16 Dec 6 - 10 San Diego, CA Q19-21/16 Rapp. Sep 27 - 29 Geneva T1E1 Dec 6 - 10* Clearwater, FL ITU-T SG16 Sep 30 Geneva TIPHON 15 Oct 4 - 8 Leipzig, Germany

* This period includes joint TR-30.3/T1E1.4 ad hoc Note 2: G.pnt work Oct. 13, Oct.14, Oct 15 (AM) meeting on DSL testing Note 3: G.pnt work Nov. 29, Nov. 30, Dec. 1 (AM) Note 1: G.pnt work: Aug. 19

YEAR 2000 STANDARDS COMMITTEE MEETING SCHEDULES AS OF AUGUST 20, 1999 Subject to Change without Notice

Committee Date(s) Location Committee Date(s) Location Q4, Q8, Q23/16 Jan 11 – 14 Ft. Lauderdle, FL TIPHON 18 May 22 - 26 Ottawa, Ont TR-30, Note 1 Jan 10 - 14 Ft. Lauderdle, FL ETSI TM6 May 22 - 26 --- Q 5-7, 21/15 Rapp Jan 27-Feb 2 Uruguay TR-30 (Proposed) Jun 12 - 16 --- Q4/15 Rapp. Jan 31-Feb 4 --- Q15/16 Rapp. July TR-41 February Maui, HI TIPHON 19 Jul 24 - 28 Munich, Germany ITU-T SG8 Feb 2 - 10 Geneva TR-41 August Vancouver, BC ITU-T SG16 Feb 7 - 18 Geneva TR-30 (Proposed) Aug 7 - 11 --- T1E1 Feb 21 - 25 Maui, HI T1E1 Aug. 14 - 18 --- ETSI TM6 Feb 28-Mar3 S. Antipolis, FR TIPHON 20 Sep 18 - 22 Japan TIPHON 17 Mar 13 - 17 S. Antipolis, FR ETSI TM6 Sep 18 - 22 --- TR-30 , Note 2 Mar 13 - 16 Dana Point, CA TR-30 (Proposed) Oct 9 - 13 --- Q4/15 Rapp. Mar 17 (PM) Dana Point, CA TR-41 November New Orleans LA Q11-15/16 Rapp. April Japan ITU-T SG16 November Geneva ITU-T SG15 Apr 3 - 14 Geneva T1E1 Nov 13 - 17 --- TR-41 May Tyson Crs, VA ETSI TM6 Nov 27-Dec1 --- T1E1 May 1 - 5 --- TR-30 (Proposed) Dec 4 - 8 ---

Note 1: G.pnt Jan 10, Jan 11 (AM) Note 2: G. pnt Mar. 15, Mar. 16, Mar. 17 (AM)

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