Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Progress in NICC xDSL Task Group Fred Howett - Nortel Networks

OFTEL INTERNET FORUM - 1st Sept Work of xDSL Task Group Established April 1998 Terms of Reference Investigate and report on the technical aspects of: Potential for DSL-Lite to be CPE in the UK Possible DSL Interference issues mutual between xDSL technologies between xDSL and existing services (eg ISDN, POTS)

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Task Group Membership Switch and terminal manufacturers (Alcatel, ECI Telecom, Ericsson, Fujitsu, Marconi, Motorola, NEC, Nortel, Racal, Siemens) Network operators (BT, Kingston, C&W, Worldcom) DTI (Telecoms + RA) BABT OFTEL

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Results 2 reports published in September open issues identified NICC response to LLU Consultation - March 1999 (above documents available on public NICC www site) Final Activities (published May 1999): Conclusions Report Addenda to 2 reports issued in September 1998

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Potential for DSL-Lite as CPE (1/3) Equipment expected to be available from mid 1999 Standards mature (insufficient for vendor interoperability) multi-vendor interoperability not expected for some time Needs metallic path (no pair gain, line extender systems) Service issues (“best effort” - affect by customer’s wiring/CPE) Need CPE approval (no EC approval exists) DSLAM may support ADSL ‘classic’ and DSL-Lite

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Potential for DSL-Lite as CPE (2/3) Potential service interactions interference with existing POTS CPE (may be reduced/prevented with filters) does not operate with some services (eg feature phone or payphones using out-band signalling, 30 k  loop) does not operate with ISDN or other DSL systems Potential EMC issues (radio interference) due to unbalance of customer wiring

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Potential for DSL-Lite as CPE (3/3) Conclusions DSL-Lite equipment only just becoming available significant push for DSL-Lite (particularly USA) need level of multi vendor interoperability need to resolve EMC and CPE approval issues Above issues may take 1-2 years to resolve.

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Possible xDSL Interference (1/2) Not all xDSL systems compatible Crosstalk forms key limitation Need for Frequency Plan/Deployment Rules Standards define PSD, but: configuration options (eg power back-off) need to consider deployment (eg reverse ADSL) non-standard systems exist

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Possible xDSL Interference (2/2) Frequency Plan/Deployment Rules Need to define objective for cable fill Dependent on access network architecture and cable type Need to take account of existing services/transmission systems and consider new generations of xDSL Need to take account of CPE eg DSL-lite, Home LAN Frequency plan based on PSD defined in standards Highly complex task  specialists + long time This issue now being studied by standards fora  frequency planning tools

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept NICC LLU Response Options 1 and 2 would require the development of a spectrum management agreement for BT access network need a system for maintaining, policing and dispute adjudication on spectrum plan have Service Availability and Maintenance issues Whilst Options 3,4 & 5 have other technical issues, spectrum management would be BT’s responsibility. Hence these options could allow market demand to be met earlier.

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Future Work Meeting on 20/8/99 as response to OFTELs LLU proposals of July 1999 xDSL TG to be forum for spectrum management TOR agreed Deliverables agreed

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept xDSL TG -Terms of Reference Develop a spectral management plan for BT’s copper access network Develop a set of rules relating to the characteristics and useage of the BT Partial Baseband Leased Circuit (PBLC) Liaise with OPF group re colocation and process issues

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Timescale Agree TOR and workplan - August 1999 Agree objective for developing spectral management and PBLC rules - Nov 1999 Draft SM plan and PBLC rules - Apr 2000 for Phase 1, July 2000 for Phase 2 TG approval of SM plan and PBLC rules - June 2000 for Phase 1, Sept 2000 for Phase 2

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Spectrum management plan Two phases:- Phase 1 covers frequencies up to 1.1 MHz, whilst protecting higher frequencies. [this covers G.Lite and ADSL] Phase 2 covers frequencies up to 30 MHz [ie VDSL] and is 3 months behind Phase 1

Fred Howett - Nortel Networks OFTEL INTERNET FORUM - 1st Sept Ongoing Issues International standards (ITU, ETSI, ANSI) EMC issues - draft MPT 1570 R&TTE Directive Home networking equipment