TlE 1.4/97-463
`
`TIE1.4
`Meeting Report
`December 8-11,1997
`Sacramento, California
`
`Chair:
`Vice Chair
`Secretary:
`
`Tom Starr (Ameritech)
`Massimo Sorbara (G/obeSpan)
`Ken Hohhof (Westell)
`
`1.
`
`OVERVIEW
`
`191 persons attended this TlE1.4 meeting, which was held December 8-11, 1997.
`
`The Working Group considered:
`
`6 Liaisons (from TISl, TR30.1, TR30.2, ETSI TM6, and ATM Forum)
`
`4 Spectral Compatibility contributions
`
`21lIDSL contributions
`
`43 ADSL contributions
`
`27 VDSL contributions
`
`1 Basic Rate ISDN contribution
`
`1 Proposed Liaison (to 1R41)
`There were no contributions on ISDN Basic Rate srr Interface, Baseband Digital Data At 64 Kb/s and Below
`(DDS), V-Interface, or CSDC Network Interface.
`
`2.
`
`BUSINESS
`
`2.1
`
`CALL TO ORDER
`
`The meeting was called to order by the Chair at 8:38 AM on Monday, December 8, 1997. The host, Level One,
`was thanked for providing facilities for the meeting, and for making copies of the letter ballot comments.
`
`2.2 ANTITRUST NOTICE
`
`The Chair reviewed Committee Tl antitrust policies. WG members were asked to review their contributions and
`advise the Chair of any material that might be in violation of antitrust guidelines.
`
`2.3 DISTRIBUTION OF CONTRIBUTIONS
`
`The contributions were distributed according to contribution list TlE1.4/97-000Rl. Several additional
`contributions were added to the list at this time and distributed.
`
`3.
`
`LIAISONSIMEETING REPORTS
`
`TIAI Dick Bobilin, Creative Communications, reported that TlAI met October 27-31 in Austin. TlA1.2
`continued its work on Network Survivability. TlA1.3 completed development of a draft standard which
`provides an Overview and Reference for GSTN Multimedia Terminals. TlAl. 7 completed development of a
`revision of ANSI Tl.S08 (Loss Plan for the Digital Network). The next TlAI meeting will be March 16-
`20 in Boulder, Colorado.
`
`1
`
`

`
`TIEl. 4/97-463
`
`TIM1 Curtis Brownmiller, MCI, reported that TIMl.3 met November 3-7 in Providence, Rhode Island. Tl.231
`(Physical Layer Performance Monitoring) is completed and should be published by ANSI in January.
`Tl.216 (ISDN Management - Basic Rate Physical Layer) has been revised and gone forward to ANSI for
`publishing. There are references to Tl.2l6-1991 in Tl.60l and Tl.60S, Dick McDonald took note of this
`to update the reference when TI.601 is revised. DSL maintenance is an active work item, and TIMl.3
`wants to make sure maintenance and operations needs are supported in Tl.4l3, but contributions and/or
`liaisons are needed. The next major work item is the optical area along with TIXl.
`
`Dick Bobilin. Creative Communications, reported on TIM1.S. Tl LB645 on a draft standard for Lawfully
`Authorized Electronic Surveillance" closed with 2 NO votes and extensive comments. Comment resolution
`was begun and will be continued at interim meetings.
`
`The next TlMl meeting will be Febrwuy 9-13 in San Diego, California
`
`TISI Dick Bobilin, Creative Communications, reported that TlS1 met November 17-21 in Dallas. A new WG,
`TISl.6, was formed to deal with number portability, and plans to meet monthly for the next year to get
`these requirements out on time. TISl.I resolved all comments from default TI LB623 on the draft
`Intelligent Network standard, which will be published as Tl.667-l998. The next TISI meeting will be
`March 23-27 in Raleigh, North Carolina.
`
`TIEl.4/97-38S (Liaison from TlSl)
`
`Discussion: TISI advises TIEl that they are revising T1.620a-1992 "Multi-Rate Circuit-Mode Bearer
`Service for ISDN" and invites comments, e.g. regarding our work on Basic Rate ISDN. Dick Bobilin said
`the main issue is updating references to TIEl.2 documents, e.g. Tl.403/408 which are being updated into a
`family of Tl.403 document
`
`Resolution: No one was aware of any reference updates, so no action was necessary.
`
`TIXI Dick Bobilin. Creative Communications, reported that TlXl met October 14-17 in Naperville, Illinois.
`TIX1.3 is concentrating its efforts on Iss. 3 text for TI.lOl, Synchronization Interfaces. TIXl.S resolved
`comments including one NO vote on TI LB63S for Iss. 3 ofTl.l05.0l (SONET Automatic Protection
`Switching), which will require a default letter ballot TIXl.S also resolved comments on revision of
`Tl.1l9.02 (SONET OAM&P Communications - Performance Management Fragment). The one NO vote is
`likely to be changed on the default letter ballot Tl LB634 on the Supplement to ANSI Tl.lOS.07-l996
`(SONET - Sub STS-l Interfac:e Rates and Formats Specification) closed on September 10, 1997 without NO
`vote or comment, and will be published as T1.105.07a-1997. This staDdard includes nxVI' Group
`interfaces. TlXl is getting heavily into optical networking. The next meeting ofTIXl will be January 13-
`16 in Orlando, Florida.
`TR30 Les Brown, Motorola, reported that there was a breakthrough at tile recent rru Q16/SG23 Rapporteur's
`Group meeting that should result in a V.pcm recoJJUDelldation in Jauwuy. Les then presented the following
`liaisons:
`
`TlEl.4/97-430 (Aspects ofxDSL Specifications which may aff'ect V-Series Modems- TR30.l)
`
`Discussion: The changes made to the ADSL psd mask will meet the needs ofV.pan modems. TR30.1
`reviewed the specs in Annex I, and while the attenuation and delay distortion specs are fiDe, they have
`concerns about the noise and distortion specs in section 1.2.1.5 - the most troubling are the 42 dB Signal-to(cid:173)
`C-notclu:d-noise ratio spec. TR30.1 believes this spec should be consistent with the + lSdBm psd spec in
`the 0-4 kHz band, while recognizing that Annex I is informative, not normative.
`
`Resolution: Will be considered as part ofLB resolution at interim meeting
`
`2
`
`

`
`TIE1.4/97-463
`
`TIE1.4/97-461 (Liaison to TlE1.4 regarding work starting in TIA TR-30.2)
`
`Discussion: TR30.2 has recently started a new project PN-4149 "Study ofDTElDCE Interfaces for xDSL
`modems". Past examples of this type of protocol are AT commands and V.8 inband commands.
`
`Resolution: The work in TRJO.2 was noted, no action was needed.
`
`TR41 Donovan Nak. NEC, reported that TR41.8.1 bas tentatively selected a fiber optic connector. Donovan was
`not at the TR41. 9 meeting but his understanding was that they approved FCC part 68 limits for ADSL.
`
`ITIJ-T Dick Stuart, 3Com, reported that Q4 of SG15 met October 27-29 in Red Bank, New Jersey. The number of
`IP announcements is up to 8. G.adsl won't be a pointer reference to T1.413 because ITU doesn't allow this,
`but no work is going forward on G.adsl anyway. It bad been hoped to point G.hdsl to an ETSI document
`but no text bas been made available. Work is going forward on G.dInt with good progress. T1.413 Iss. 2
`text will be attached to Dick's Rapporteur's report as working text - this doesn't mean it bas been agreed.
`G.bs will follow the same concept as V.8 for voiceband modems, Les Brown is the editor. G.test will
`provide for a uniform way of testing DSLs. A new G.oam was started. and an editor was assigned. It will
`make provisions for an eoc to transport operations and maintenance information. There was much interest
`and support for G.lite. The draft CAP/QAM document was made available for information only, the group
`is waiting to see what comes out of the letter ballot process to see if it should be progressed. The group
`discussed and reaffirmed the ITU direction to "divide and conquer", i.e. write separate recommendations for
`different layers. The next meeting is a full SGI5 meeting Febnwy 9-20 in Geneva, Switzerland (note -
`you must be an ITIJ member to attend). After that, the next full SGI5 meeting is October 12-23 in Geneva.
`
`Hans Frizlen asked ifG.dInt will be based on Iss. lor 2 ofT1.413 - Dick said the intent is Iss. I, which is
`the current working text, although he noted that ITU is contribution driven. There was a discussion of how
`to contribute to ITIJ - company contributions direct to US Study Group B for submission to ITU, or bring to
`T1E1.4 and drive toward a TIEl submission to US Study Group B for a US country position at ITIJ. The
`conclusion was that TIEl is the technical advisory group that US Study Group B looks to as the preferred
`path for US positions on DSL standards. The next Study Group B meeting is January 23 in Boulder,
`Colorado. Les Brown added that G.bs would be modulation, not tone, based, and G.dmt would use G.bs, so
`the tone-based front end negotiation would be removed from T1.413 ifindeed G.dInt is based on T1.413. It
`bas been agreed that there will be an "escape mechanism" to support interoperation with T1.413. There is
`some debate about where to place ADSL in the spectrum, e.g. some countries want ADSL over ISDN.
`
`ETSI Hans-Jarg Frizlen, Ericsson, reported that ETSI 1M6 bad two JIlt"dings since the last TIEl meeting - one
`in Lannion, France September 30 through October 3, and one in Verona, Italy November 17-21. TM6 has
`four work items: ISDN basic rate, HDSL, ADSL and VDSL.
`
`Basic Rate ISDN (only at the Verona meeting>:
`
`The living list for the possible revision ofETR 80 was updated, and a number of points were either resolved
`or deleted (a copy of the living list was provided to Dick McDonald). One major point was brought up -
`when the psd mask was developed, it stopped at 500 kHz because no one expected higher speed xDSL
`systems in the local network. A new study point was added to extend the psd mask for 2BIQ and 4B3T
`transmitters up to 30 MHz to protect xDSL systems from ISDN-BA, and there was Provisional Agreement
`on the psd mask. The question whether to go forward with a revision (version 3) ofETR 80 will be decided
`at the next meeting.
`
`HDSL:
`
`ETR 152 covers 1, 2 and 3 pair HDSL systems using 2B1Q modulation, with an informative CAP annex.
`The text was upgraded into the format for the new ETSI Technical Specification (ETS) deliverable. After
`discussion a major change was made - it was decided to make both 2BIQ (1,2 or 3 pairs at 2320, ll68 or
`
`3
`
`

`
`TIE 1.4/97-463
`
`784 kbls) and CAP (1 or 2 pairs) normative in the ETS. TM6 is monitoring the decisions made in TlE1.4
`on HDSL2, and has an inactive project for rate adaptive HDSL.
`
`ADSL:
`
`After discussion at two meetings, a request to immediately start work on a detailed ADSL spec was not
`accepted. TM6 decided to wait for finaJjzation ofT1.413 Iss. 2 and possibly the CAP/QAM standard.
`When TlE1.4 has completed the letter ballot process, then 1M6 will decide whether to write a delta
`document or a complete spec, based on the Tl standard with necessary European additions.
`
`TlE1.4/97-433 (Liaison from ETSI 1M6)
`
`DiscussioD: TIE1.4 is asked to reconsider the ADSL psd mask spilling into VDSL as part of the T1.413
`Iss. 2 letter ballot resolution process. There are some concerns about G.lite from the European point of view
`- Europe doesn't always have metallic lines available in the access network, they have tax and metering
`pulses in the range 12-16 kHz, and they have a problem with impedance change when POTS goes offhook
`and there is no POTS splitter. 1M6 is not planning to submit a formal liaison to SGIS. A VDSL report is
`included for information. Progress and near agreement was accomplished on noise models, payload rates
`and test loops. 1M6 hopes that TlE1.4 can use much of the Part 1 VDSL ETS document.
`
`Les Brown asked if metering pulses didn't afl'ect G.dmt as well as G.Lite? Hans said this was recognized as
`an issue for G.dmt as well, but in this case there is a POTS splitter which can have requirements placed on
`it to keep the metering pulses out If you have a splitterless system, the metering pulses go straight into the
`ADSL system, so the problem is much more severe.
`
`ResolutioD: Will be addressed as part of letter ballot resolution at the January interim meeting.
`
`VDSL:
`
`1be Draft TS Part I covering system and network requirements, noise environment, the amateur radio
`issue, and all those points that are independent of the electrical solution and which are mostly coming from
`the network operators is about 40 pages, and is due to be finalized and accepted at the TM6 level at the next
`meeting in Madrid the end of January. 1be rules for an ETS do not require that it go to public inquiry. so it
`is possible that Part I may be published in spring of 1998. After this T.M6 will start on Part 2 which will
`contain electrical and traDSmission requirements. TM6 originally had the idea that TIE1.4 had made a lot
`of progress on VDSL that TM6 could take over, but this is not the case, and TlE1.4 has the two ADSL
`letter ballots to deal with. In any case, TM6 work will be done in cooperation with TIE1.4, and there will
`not be different solutions between the two groups if it can be avoided.
`
`Hans will be retiring from Ericsson at the end of December 1997. He will continue as chair of 1M6 under
`ETSI sponsorship for the next 1 or 2 years. Official liaison from TM6 to TIEl.4 will be maintained by Jan
`BostrOm of Ericsson.
`
`4
`
`

`
`TIE 1.4/97-463
`
`Future meetings:
`
`January 26-30, 1998
`April 20-24
`June 22-26
`September 21-25
`
`Madrid. Spain
`Antwerp, Belgium
`Lulei. Sweden
`Wien, Austria
`
`February 22-26, 1999
`May 3-7
`September 13-17
`November 29-December 3
`
`tbd
`tbd
`tbd
`tbd
`
`The Chair and the WG thanked Hans for his many years of liaison to TIE1.4 and bis efforts toward the
`close working relationsbip between TM6 and TIE1.4.
`
`IEEE 802.14 No report at this meeting.
`
`ADSL Forum Frank Van der Putten, Alcatel, reported that ADSL Forum met December 3-5 in San Francisco.
`There were no liaisons. 5 documents went to letter ballot including the ADSL line MIB (line code
`independent), CPE interfaces and configurations, and packet mode. Work started on CO interfaces and
`configurations. There was a round table on splitterless ADSL, and it was decided to form a task force to
`continue discussion. Work started on test suites for interoperability, and on ATM layer configuration
`considering dual latency and rate adaptation. The next meeting is March 31 to April 2 in Tel Aviv.
`
`A TM Forum Subra Ambati, Lucent-ACGS, reported that the RBB group reviewed new proposals from Nortel et
`al, and sent a liaison on PPP over ATM to ADSL Forum.
`
`TIE1.4/97-386 (Liaison from ATM Forum dated September 5)
`
`Discussion: This liaison was addressed to ADSL Forum with a copy to TIEL ADSL Forum is requested to
`reconsider fixed allocation between fast and interleaved channels at startup, and consider non-service
`affecting dynamic reallocation. Information is requested for the September 22, 1997 joint meeting in Paris.
`Concerns are raised about the practicality of fixed delay in the event ofDRA because of the granularity of
`the interleaver depth.
`
`Resolution: For information only.
`
`TlE1.4/97-387 (Liaison from ATM Forum dated October 31)
`
`Discussion: This liaison responds to our liaison TIE1I97-029, and agrees to study the effects of data loss
`on ATM. Tom Starr noted that as we get further into DRA and rate repartitioning, we should keep ATM
`Forum informed. Alan Weissberger noted the importance of characterizing the maximum time for DRA
`and rate repartitioning to be completed. asks why TIEl.4 doesn't want to address. Frank Van der Putten
`thought the question was the time until the ATM layer is informed. and in:fact we do better than this
`because, according to the DRA Annex, we inform the ATM layer ahead of time (Alan disagreed with this
`view). Frank also noted the Annex is still informative and people are still working on DRA, so the
`information to quantify these delays is not available yet
`
`Resolution: For information only.
`
`5
`
`

`
`TIE1.4/97-463
`
`DAVIC
`
`No report at this meeting.
`
`4.
`
`REVIEW/APPROV AL OF REVISED AGENDA
`
`The chair presented the following contribution:
`
`TlE1.4/97-382RI (Revised Preliminary Agenda for this TlE1.4 Meeting - Chair)
`
`Discussion: The chair provided a revised agenda for the meeting.
`
`Resolution: Approved as modified by the WG.
`
`Agenda for Future Meetings
`It was decided to place Spectral Compatibility after HDSL2 on the agenda starting with the March meeting, but
`this was discussed again on Thursday and Spectral Compatibility was moved to after ADSL and before HDSL
`(typically Wednesday afternoon) starting with March. There were no objections, and this was Agreed.
`
`5.
`
`REVIEW/APPROV AL OF MINUTES OF SEPTEMBER MEETING
`
`TlE1.4/97-362 The minutes of the last regular meeting of September 22-2S, which were distributed in the
`mailing, were approved with the following changes:
`
`•
`
`97-362A should say "Iss. 2" instead of "Iss. 3".
`
`Frank noted that there is proposed text in Alcatel's letter ballot comments.
`
`6. SPECTRAL COMPATIBn.ITY
`
`TlE1.4/97-384 (Project Proposal: Standard for Spectral Compatibility of Twisted Pair Transmission Systems -
`Ameritech)
`
`Abstract: TIEl currently has a study project for Spectral Compatibility. This existing project could
`generate a Technical Report, but not a proposed Standard. Due to the increased importance of Spectral
`Compatibility, an ANSI Standard would be more appropriate. As an ANSI Standard, the Spectral
`Compatibility specification would have better visibility within the industry. Thus, a new project is proposed
`which is largely identical to the existing Study Project, except that the new project would be chartered to
`develop a proposed ANSI Standard. TlE1.4 is asked to review the attached TI Project Proposal, for
`possible recommendation to TlEI for letter ballot
`
`Discussion: In response to questions, Tom Starr provided the following clarifications:
`
`•
`
`•
`
`•
`•
`•
`
`it is not the intent to do a survey of existing loop plant and installed equipment, but existing services
`could be defined as protected
`it is anticipated that the psd for future xDSLs will be specified according to the current working
`agreement that there would be 2 methods, a simple mask, and a case-by-base demonstration that the
`proposed system is crosstalk compatible with each of the protected systems
`if necessary, certain existing systems could be grandfathered
`new systems would have to comply with the psd mask or could be justified on a case-by-case method
`it is not the intent to include other impairments, e.g. RFI or impulse noise
`
`It was agreed to add "cable characteristics" as item 4 under project outputs. There was some discussion of
`making the project schedule more realistic, but it was agreed not to debate the schedule. A few editorial
`corrections were made. Bahrooz Rezani of APC agreed to act as editor.
`
`6
`
`

`
`TIE1.4/97-463
`
`Resolution: There were no objections to changing this to a Standard project. Tom Starr agreed to
`incorporate the changes into 97-384R1 for the TIEl plenary, with the WG recommendation that it go out
`for letter ballot.
`
`TlE1.4/97-404 (Spectral Compatibility of ADSL and VDSL, Part 1: The Impact ofVDSL on ADSL Performance
`- Amati)
`
`Abstract: This document detennines whether use of the band below 1.104 MHz by VDSL systems is
`feasible given the constraint that the impact ofVDSL on ADSL performance must be minimal. The
`contribution presents results of ADSL simulations assuming coexistence with various VDSL system designs
`and concludes that in the network configuration in which VDSL most severely degrades ADSL
`performance:
`
`•
`•
`
`•
`
`use ofa VDSL power boost in the band below 1.104 MHz is not feasible;
`the VDSL PSD in the frequency band below 1.104 MHz should be less than or equal to -90 dBmIHz in
`the upstream. direction; and
`the VDSL PSD in the frequency band below 1.104 MHz should be less than or equal to -78 dBmIHz in
`the downstream direction
`
`It is concluded that the impacts ofIDD and FDD solutions on ADSL performance are essentially equivalent
`in the network configuration considered, and that VDSL should avoid use of the ADSL band for either
`upstream or downstream transmission in at least this configuration.
`
`Discussion: The contribution considers ADSL and VDSL in the same cable. In order to maximize VDSL
`performance, it is desirable to use the BWbeiow 1.104 MHz for VDSL as well as ADSL. In some
`situations, spectral incompatibility may result, and in this case ADSL is an existing service so VDSL must
`not impair ADSL. Can VDSL use the spectrum below 1.104 MHz at +60 dBmIHz without impacting
`ADSL performance? "CO mix" is not a problem ifwe are only considering VDSL impact into ADSL, but
`for "CP mix", VDSL upstream NEXT degrades ADSL downstream performance. Even at -60 dBmIHz,
`there is significant degradation (e.g. 6M ADSL cut down to around 3M). VDSL downstream FEXT into
`ADSL downstream also causes significant degradation. VDSL power boost in the ADSL band is not
`possible, and even -60 dBmIHz is a problem. For either FDD or TDD, the upstream VDSL psd below
`1.104 MHz should be no higher than -90 dBmIHz, and downstream no higher than -78 dBmIHz.
`
`Resolution: For information only.
`
`TlE1.4/97-425 (Comparison of the Effect of Two ADSL PSD Masks on the Capacity ofVDSL - Savan)
`
`Abstract: This document examines the effect of two ADSL downstream PSD masks on the channel of
`VDSL: the proposed revised mask for ADSL Iss. 2 and a mask recently proposed by Nortel. It is shown
`that the Nortel mask significantly improves VDSL capacity in the presence of ADSL downstream NEXT,
`but only slightly in the presence of ADSL downstream FEXT. We also show that, regardless of which
`ADSL mask is used, it would be very difficult to achieve the VDSL ratelreach goals in the presence of
`ADSL crosstalk.
`
`Discussion: This contribution compares the Iss. 2 mask and the tighter Nortel mask #5 from 97-351.
`Analysis was performed for pure NEXT and for pure FEXT - the reality for a specific implementation will
`probably be between these two scenarios. The analysis is a theoretical upper bound not taking into account
`implementation losses. The results show that even a single ADSL downstream NEXT disturber may
`prevent VDSL from meeting requirements. The Nortel mask helps NEXT significantly, but only slightly
`improves performance under FEXT. John Cioffi pointed out that even if an echo canceled VDSL system
`were possible. capacity would probably be limited by self-crosstalk.
`
`Resolution: For information only.
`
`7
`
`

`
`TIE 1.4/97-463
`
`TlE1.4/97-416 (Spectral Compatibility Issues for VDSL - FSAN VDSL working group consisting of British
`Telecom, France Telecom, GTE, Deutsche Telekom, Bell Canada, CSELT and Swisscom)
`
`Abstract: Crosstalk noise masks are presented which are recommended to be used when assessing the
`feasibility of VDSL transmission proposals. The basis and assumptions used when developing the noise
`masks are also given. Essentially a more restrictive mask for ADSL is applied here that results in reduced
`crosstalk powers. As a consequence, 2 Mb/s HDB3 systems (if included) contribute significantly to the total
`background noise PSD. This model also reflects the reasonable property that crosstalk of other xDSL
`systems is injected at multiple locations along the subscriber line. This document is essentially identical to
`1D21 presented at ETSI TM6 in November.
`
`Discussion: The intent is to provide vendors with a compromise, realistic set of noise masks. Two
`scenarios were considered: fiber to the exchange (VDSL collocated with ADSL) and fiber to the cabinet
`(VDSL and ADSL not collocated). Both scenarios divide VDSL between 2 drop off points. The noise is
`lower for fiber to the cabinet because distance attenuates the signals. The noise mix includes ISDN, HDSL,
`ADSL and VDSL. For some operators, the noise should also include primary rate ISDN. Simulation
`results show a clear need for a tighter ADSL mask to allow future service deployment with minimum
`impact.
`
`Resolution: For information only.
`
`7. VDSL
`
`7.1 Service Characteristics & System Requirements
`
`TlE1.4/97-282 (Proposal: Option for in-band POTS and ISDN - Telia Research)
`
`Abstract: An option is proposed allowing VDSL to use the spectrum now reserved for narrowband
`services, such as POTS and ISDN. The main motives for the proposal are:
`
`• Provide lower network complexity and maintenance by avoiding duplicate line cards
`Increase the number of customeIS using VDSL for rates below IS Mbls. This is because when VDSL
`•
`can use the full spectrum, the reach can be significantly extended. For example, the reach increases by
`up to 1000 m for a 2 Mb/s symmetric service on TPI in a CO based scenario.
`
`Discussion: Reasons for making the proposal include:
`
`•
`•
`•
`•
`•
`•
`
`only one line card (to support both wideband and narrowband services)
`no analog frequency splitter
`reduction of cabling
`fewer cabinets
`flexibility in introduction of narrowband services (i.e. IIlOIe than 2 POTS/lSDN lines)
`extended reach
`
`Canying POTS digitally over VDSL requires dual latency and an optional spectrum mask starting from
`DC. Norm Smith asked about "lifeline" service, and while Hans Frizlen pointed out that ISDN in North
`America is not positioDed as oft"ering service during a power outage. Tom Starr said we can't do this if
`VDSL is positioned as giving VDSL plus the same old POTS as it exists today over the same loop. Alan
`Weissberger called attention to implications for higher layers, e.g. canying voice over ATM using VTOA.
`
`Resolution: Placed on the living list as Under Study.
`
`TlE1.4/97-392 (Unified Link Management - DSC)
`
`Abstract: This contribution presents a common framework to address the link management of xDSL
`systems.
`
`8
`
`

`
`TIE 1.4/97-463
`
`Discussion: A scheme is needed to manage xDSL links, which is independent of transmission technology.
`It is proposed to define 3 fundamentals:
`
`•
`•
`•
`
`a bi-directional clear eoc
`a link layer protocol for eoc messages
`a network management protocol and MIB
`
`An eoc data link is necessaIY to delineate messages in the eoc bitstream - it should be common to all flavors
`of xDSL. and based on PPP in HOLC-like teaming. It is recommended that a bi-directional clear eoc be
`defined for the VDSL rc. ADSL Forum Netwolk Management group recommends SNMP as the netwolk
`management protocol. and has ag:reed to define and ADSL MIB. Ken Hohhof asked about the
`recommendation that this scheme be used for all xDSLs and whether this would include systems like
`HDSL2. Tom O'Shea thought using an SNMP MIB instead ofbit-orienteci messages for low-level functions
`like NEBEIFEBE for systems like HOSL might require too powerful a processor. Les Humphrey thought a
`universal approach might be too powerful for some systems and not enough for others. Alan Weissberger
`cautioned against excluding any mechanism, noting that when higher layers are unavailable, it might be
`necessary to revert to physical layer mechanisms.
`
`Resolution: Placed on the VDSL living list as Under Study.
`
`TIE1.4/97-393 (proposed EOC Transport Protocol- DSC, Diamond Lane, Efficient Networks, Paradyne and
`Ericsson)
`
`Abstract: This contribution provides the details for a transport protocol for the EOC in VDSL systems.
`This protocol is based on the HOLC-like link layer defined in RFCI662. The goal is to use the same type of
`protocol in ADSL DMT, CAP/QAM and also in VDSL systems, so that the EOC protocols be independent
`of the particular transmission technology.
`
`Discussion: The proposal is the sante as RFCI662 with many of the options eliminated. TI.413 Iss. 2
`defines how to provide a clear channel EOC, this proposal would add higher layers which are not currently
`specified in Iss. 2. Peter Melsa asked about adding a lot ofbyte-orienteci overhead for what are typically
`very short messages. Les Humphrey noted that ADSL Forum has not agreed that ADSL and VDSL will
`necessarily use identical rcs. The address field could be used to provide point-to-multipoint operation for
`VDSL. There was a discussion ofwhether this protocol could be applied to HOSL2, but for now the
`proposal is for VDSL.
`
`Resolution: Placed on the VDSL living list as Under Study.
`
`TlE1.4/97-131R3 (Draft VDSL System Requirements - Editor)
`
`Resolution: For review.
`
`TlE1.4/97-010R3 (VDSL System Requirements Living List - Editor)
`
`Resolution: For review.
`
`TlEI.4/97-164R2 (VDSL Editor's Suggestions to align VDSL system requirements with ETSI 1M6 VDSL
`DTS!IM)
`
`Abstract: The ETSI VDSL requirements DTSI1M-06003-1 and the present ANSI VDSL requirements
`97-133R3 have increased in deviation since last writing of this document. This is largely due to deferral of
`VDSL in ANSI (ADSL Iss. 2 having priority) and a coincidence of calendar where two ErSI meetings
`occurred since the last ANSI meeting. Since TEI.4 and 1M6 have agreed to wolk closely on VDSL, the
`ANSI VDSL editor suggests actions that can bring the two documents into substantial alignment, except for
`the national differences that are to be expected.
`
`9
`
`

`
`TIEl.4/97 -463
`
`Discussion: ETSI requires one splitter for ISDN (2BIQ and 4B3T) and POTS. ETSI references European
`specs for climatic requirements - Dennis Rauschmayer agreed to supply comparable ANSI or Bellcore
`sources, and the editor agreed to change "climatic" to the more common US wording "environmental".
`Walter Chen volunteered at the September meeting to coordinate issues related to POTS and ISDN splitters,
`but Walter reportedly changed employers and in any case was not at the meeting, so Robin Gangopadhya of
`Valor Electronics volunteered to do this. A volunteer is needed to coordinate clocking and timing issues.
`
`Hans Frizlen clarified that there is controversy in TM6 over power boost, wbich may cause the noise
`environment to be very dyDamic - this is why it is under study. 1.1. Werner clarified that bis proposal was
`not for dynamic power boost. Jacky Chow suggested also including power cutback. Terry Throop said
`there is no uMnjmity in ETSI on including micro-interruptions. Les Humphrey noted that some useful TC
`information is starting to flow from ETSI 1M3. Les clarified that the I ms latency spec is only for the
`application independent TC and does not include an allocation for the ATM TC. Ken Hohhof asla:d about
`splitterless VDSL - Norm Smith and Greg Sherrill noted the Lucent contribution from the September
`meeting that indicated a LPF is needed to isolate bridge taps in premise wiring.
`
`Resolution: It was decided that the following items needed further study, and they were placed on lists for
`the appropriate Issue Coordinators to resolve:
`
`frequency-dependent longitudinal balance spec
`•
`startup
`•
`transmit power boost
`•
`detailed test configurations
`•
`• ETSI noise models
`• micro-intemJptions
`
`The following recommendations were Agreed:
`
`•
`•
`•
`•
`
`in the TC area, add maintenance channel and NTR. to the reference diagrams
`change transmit power to + 11.5 dBm (but boost under study)
`the 4 numbered Editor recommendations under Test Configurations (but configurations under study)
`use same 7 noise classes as ETSI (but noise models under study)
`
`TlE1.4/97-16SR2 (VDSL Editor suggestions for progress completion ofVDSL study phase)
`
`Abstract: The VDSL System Requirements is now in Revision II. Some suggestions are made as to how
`to move this document to a completed state and to progress VDSL efforts in general. Specifically, 3
`champions are suggested in the areas ofT/C, Splitter/Analog requirements, and PerfonnancelTesting.
`
`Resolution: Resolved with assignment of Issue Coordinators.
`
`TlEI.4/97-325 (Blind Start-up - Lucent)
`
`Abstract: Blind start-up has many desirable features, including ease of interoperability and simplicity of
`implementation. This paper presents a short tutorial on blind start-up and introduces a new blind
`equalization algoritbm called MultiModulus Algorithm (MMA), which is particularly well suited to the
`VDSL application.
`
`DilClllSion: The MultiModulus algorithm is less known than other algoritbms like RCA or CMA, but more
`powerful at achieving initial convergence without "wrong (rotated or diagonal) solutions". MMA is
`particularly powerful for non-square constellations. Blind startup eases interoperability between vendors
`aDd simplifies transceiver implementation. Advantages ofMMA include more reliable initial convergence
`than RCA, it does DOt require a rotator like CMA, and more flexibility than both RCA and CMA to
`accommodate nonsquare and very dense constellations.
`
`10
`
`

`
`TIE1.4/97-463
`
`Greg Sherrill asked about shaping - 1.1. Werner said shaping has not been considered for VDSL because of
`the high symbol rates. It was noted that blind start-up is already on the living list as Under Study (see
`97-104 from February). There was some discussion and controversy as to whether blind startup is a system
`requirement or line code dependent
`
`Resolution: Remains on the living list as Under Study.
`
`7.2 Impairments & EMl
`
`TlE1.4/97-274Rl (Flat Pair Field Testing - Leakage into the 20 m