1. www.btwholesale.com/consult21 Pathfinder Working Group BT Centre Showcase, Registration: 9.45 am Start time: 10.00 am

2. Pathfinder Working Group - Agenda.Introductions.Terms of reference and objectives of Pathfinder Working Group.Cardiff - The facts of Interconnection.BT’s view of technical issues/risks inherent in a hybrid interconnection model during Pathfinder.Proposed transfer methodology from DLE to NGS.Requirements for Pathfinder Programme - a free form brainstorming session designed to deliver a set of requirements specific to Pathfinder..AOB Customer Communication Plan TSG Update

3. www.btwholesale.com/consult21 Pathfinder Working Group Working Group Terms of Reference Keith Fowler - Pathfinder Programme Manager.

4. Pathfinder Working Group Membership Industry representatives and BT Wholesale (co-chair arrangement) Proposed Terms of Reference Phase 1 (now until June 05): Agree to conditions for collaboration during the Pathfinder period (Out of service Oct 05 – Dec 05, In service Jan 06 – March 06) Capture Pathfinder Requirements from BTW Customers (close by 28-Feb) This has already begun through one-on-one calls Agree to measurement points and reporting structure to provide all Pathfinder participants equal access to experiences and information Phase 2 (July 05 – April 06): Issue of System Alternation Notices for Cardiff DLEs Trial Industry collaboration in the migration of: Interconnect (target beginning migration Oct 05) End Customers (mass migration Jan-Mar 06) Review of experiences and results Working Group Scope All matters relating to migration of interconnect arrangements and consumer and business customers to a 21CN environment, while not overlapping other working groups. Meeting Frequency Monthly or more frequently as required

5. Pathfinder Working Group Within Scope of Pathfinder Working Group Determine criteria for collaboration during this period Issue of System Alteration Notifications in July Defined methodology for movement of end customer lines Defined methodology for movement of services Defined additional reporting requirements to test effectiveness of trial. Outside Scope of Pathfinder Working Group An agreed technical arrangement to enable DLE closure (Interconnect Working Group) Agreed commercial arrangements for rearranging interconnects Charging Principles (Interconnect Working Group) Contract Alterations (Standard Contracts Forum) Future interconnect (IP, etc.) (Interconnect Working Group) LLU (Broadband and LLU Working Group) Any other workgroup themes

6. www.btwholesale.com/consult21 Pathfinder Working Group Cardiff – The facts of Interconnection Mark Ward, Head of Interconnect & Numbering Services

7. Cardiff Pathfinder area - Current Interconnect Arrangements 9 impacted DLEs - 7 in Cardiff, plus Bridgend and Pontypridd Cardiff DLE units: CF/TY, CF/UC, CF/UD, CF/UE, CF/UF, CF/UG, CF/UL Bridgend DLE unit: BNP/DA; Pontypridd DLE unit: PN/DA All Cardiff DLE units are co-located with Cardiff Iolite NGS 7 impacted Altnets 80% of circuits from 3 Altnets Volumes are for all interconnect E1s, including FRIACO

8. www.btwholesale.com/consult21 Pathfinder Working Group BT’s view of technical issues/risks inherent in a hybrid interconnection model during Pathfinder

9. Risks and Issues associated with Interconnection arrangements and Pathfinder. Risks:- Non Movement of CP DLE Capacity prior to Pathfinder could result in:- Increased risk of call routing errors due to a complex data set ( 21CN – legacy network – CP’s network ) Increased risk of QoS issues e.g. call routing errors & over-used capacity Any Operational issues resulting would cause increased manpower demands on both BT and CPs Complication of eventual movement of Capacity prior to DLE closure. Failure to fully test the full 21CN migration process and amend process if required

10. Risks and Issues associated with Interconnection arrangements and Pathfinder. Issues Known issues include:- Billing in line with commercial offer - EBC? Some unsupported products post end-customer transfer e.g RBWF Trial Contract CPS SAD calls Prove designs for continuity of Interconnect products to/from end customers. Fall Back arrangements and criteria. Availability of new 21C Interconnect Products

11. Mitigating Risks Goal is to migrate CP Interconnect prior to DLE end-user migration Provide sufficient time to assure stability for all Avoid complex routing (21CN - NGS -CP) Avoid need to replicate legacy/PSTN routings and data structures Minimize impact on perceived QoS (complex call routing/’tromboning’) Can migrate CP circuits over time without need for whole DLE at once migration Disengage CP circuits from actual DLE closures Pathfinder offers the opportunity to collaborate on the full migration process Trial methodology for moving CP Interconnect circuits over time (not directly tied to mass migration schedule) Trial methodology for migrating end-users whole DLE at once Provide feedback to improve processes prior to main 21C roll-out

12. www.btwholesale.com/consult21 Pathfinder Working Group Proposed Transfer Methodology from DLE to NGS

13. Legacy TDM Support - Transfer Engineering Proposals Aims :- To de-risk the transfers by use of existing NGS switches and network routings. To provide separation of agreed transfer activities from progress on 21C build and DLE closures. To enable balanced workload for all. Scenarios :- 4 that will apply in most circumstances - mix and match. Last 2 may apply to balance NGS capacity Not exhaustive - other options inc. Ceasing Capacity, new 21C products etc. Not prescriptive - subject to bi-lateral agreement with each individual customer.

14. Figure 1a - Configuration ‘1’ - ISI Direct to DLE and NGS Sites No Spare NGS CP Route Capacity - Interconnect Scenario Before Transfer DLE SITE  CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE 3 E1s 13 E1s NGS SITE CP Capacity BT Capacity

15. DLE SITE NGS SITE CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE 3 E1s  13 E1s Figure 1b - Configuration ‘1’ - ISI Direct to DLE and NGS Sites No Spare NGS CP Route Capacity - Interconnect Scenario After Transfer CP Capacity BT Capacity

16. Figure 3a - Configuration ‘3’ - ISI Direct to NGS Site with IEC to DLE Site No Spare NGS CP Route Capacity - Interconnect Scenario Before Transfer DLE SITE  CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE CP Capacity BT Capacity 3 E1s NGS SITE 13 E1s IEC

17. Figure 3b - Configuration ‘3’ - ISI Direct to NGS Site with IEC to DLE Site No Spare NGS CP Route Capacity - Interconnect Scenario After Transfer DLE SITE  CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE CP Capacity BT Capacity 3 E1s NGS SITE 13 E1s

18. Figure 6a - Configuration ‘6’ - ISI Direct to NGS Site with IEC to DLE Site No CP Route to Non Parent NGS - Interconnect Scenario Before Transfer DLE SITE  CP Switch DLE 2 21CN21CN MGWMGW METRO NODE 3 E1s 13 E1s CP Capacity BT Capacity NGS PARENT NGS SITE NGS NON PARENT NGS SITE IEC

19. Figure 6b - Configuration ‘6’ - ISI Direct to NGS Site with IEC to DLE Site No CP Route to Non Parent NGS - Interconnect Scenario After Transfer DLE SITE  CP Switch DLE 2 21CN21CN MGWMGW METRO NODE 3 E1s 13 E1s CP Capacity BT Capacity NGS PARENT NGS SITE NGS NON PARENT NGS SITE 3 E1s New Route (if not already existing)

20. www.btwholesale.com/consult21 Requirements Capture for Pathfinder Programme.

21. Pathfinder Working Group Within Scope of Pathfinder Working Group Determine criteria for collaboration during this period Issue of System Alteration Notifications in July Defined methodology for movement of end customer lines Defined methodology for movement of services Defined additional reporting requirements to test effectiveness of trial. Outside Scope of Pathfinder Working Group An agreed technical arrangement to enable DLE closure (Interconnect Working Group) Agreed commercial arrangements for rearranging interconnects Charging Principles (Interconnect Working Group) Contract Alterations (Standard Contracts Forum) Future interconnect (IP, etc.) (Interconnect Working Group) LLU (Broadband and LLU Working Group) Any other workgroup themes

22. www.btwholesale.com/consult21 ADDITIONAL TRANSFER ENGINEERING SLIDES – FOR INFORMATION ONLY

23. Figure 2a - Configuration ‘2’ - ISI Direct to DLE and NGS Sites Spare NGS CP Route Capacity - Interconnect Scenario Before Transfer DLE SITE  CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE 3 E1s 13 E1s 10 used for BH traffic NGS SITE CP Capacity BT Capacity

24. DLE SITE NGS SITE CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE  3 E1s Figure 2b - Configuration ‘2’ - ISI Direct to DLE and NGS Sites Spare NGS CP Route Capacity - Interconnect Scenario After Transfer 10 E1s CP Capacity BT Capacity

25. Figure 4a - Configuration ‘4’ - ISI Direct to NGS Site with IEC to DLE Site Spare NGS CP Route Capacity - Interconnect Scenario Before Transfer DLE SITE  CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE CP Capacity BT Capacity 3 E1s NGS SITE 13 E1s IEC 10 used for BH traffic

26. Figure 4b - Configuration ‘4’ - ISI Direct to NGS Site with IEC to DLE Site Spare NGS CP Route Capacity - Interconnect Scenario After Transfer DLE SITE  CP Switch NGS DLE 2 21CN21CN MGWMGW METRO NODE CP Capacity BT Capacity 3 E1s NGS SITE 10 E1s

27. Figure 5a - Configuration ‘5’ - ISI Direct to DLE and NGS Sites No CP Route to Non Parent NGS - Interconnect Scenario Before Transfer DLE SITE  CP DLE 2 21CN21CN MGWMGW METRO NODE 3 E1s 13 E1s CP Capacity BT Capacity NGS PARENT NGS SITE NGS NON PARENT NGS SITE

28. Figure 5b - Configuration ‘5’ - ISI Direct to DLE and NGS Sites No CP Route to Non Parent NGS - Interconnect Scenario After Transfer DLE SITE  CP DLE 2 21CN21CN MGWMGW METRO NODE 3 E1s 13 E1s CP provided (funded) BT provided (funded) NGS PARENT NGS SITE NGS NON PARENT NGS SITE 3 E1s