1. WBC Quality of Service (QoS) Options 23 rd October 2008 Andy Maddocks Dave Brennan Paul Fishburn Paul Burke

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3. Agenda Elevated and Standard End User Access (EUA) Options Quality of Service (QoS) Application Fit Overview of QoS options –Best Efforts –Assured Rate –Real Time –DDQ Capacity Management and performance measures QoS Pricing Structure Q&A 2

4. End User Access Options – Elevated vs Standard Standard You get at least 2Mbit/s for 90% of the time over the busiest 3-hour period Blue print being written and led by the Fibre product team on suitability 20c use this for VOIP today with mixed results. Do not recommend being used for primary voice Elevated If high congestion occurs and you selected Elevated you have more throughput. You get at least 3Mbit/s for 90% of the time over the busiest 3-hour period. Cost is £1.70 in dense and £3.40 in other cells per EU per month. This does not guarantee packets would not be delayed. Orderable via the new 21c interface Equivalent in 20c are IPstream Office and BT IPstream Max Premium Elevated is a premium service that allows a higher percentage of traffic throughput when compared to the Standard option. 3

5. Best EffortsAssured Rate QoSReal Time QoS **DDQ ** DataVideoVoiceData Web browsing Music/video publishing Email & interactive gaming e-Commerce & instant messaging Increased interactivity, bandwidth & traffic volumes Increasing variety of applications necessitates QoS mechanisms to protect more demanding applications High Definition Higher Bandwidths More efficient codec's More resilient to losses & congestion Constant Picture Quality vs. Constant Bit Rate IP Telephony, voice messaging, video telephony Increasingly demanding QoS requirements due to higher interactivity Increased signaling and control demands Systems’ performance demands (e.g. call centre systems) Dedicated downstream end to end bandwidth. Continually available. Less complex set up than Assured rate. QoS Application Fit - Class levels & associated application characteristics 4

6. The Choice – Priority of Applications Best Efforts Has 3 options aimed at Data applications. Sub* Best Efforts Priority* Real Time** * Not yet available dates to be confirmed ** Real Time dependant on prioritisation of product enhancements Highest option of QoS aimed at any application needing low latency and jitter. Strict priority Higher quality of VOIP Multiple channels (220,350,700 k\bits) 0.01 packet loss Reduced risk of bursts of high latency Not available on 20c 5

7. The Choice – Dedicated Bandwidth Dedicated Downstream QoS (DDQ) Clear channel dedicated bandwidth Set up as part of end user provision order Available 24 / 7 Capacity driven application i.e. CVLAN capability Closest 20c product is Datastream Packet marking is the same as Assured Guaranteed only downstream End User line must be able to support the dedicated service Assured Aimed at Video applications Bookable sessions of dedicated traffic up to 24hrs in duration Default 5hrs duration. Capacity driven application i.e. CVLAN capability End User line must be able to support the bandwidth selected Customer Enablement i.e. configuration set up Order via new 21c interface CP has upfront costs of system development Advanced Services is the closet equivalent on 20c 6

8. ClassDSCP codepointBinary valueDecimal value Real-TimeEF 101 11046 AssuredAF11001 01010 Best Effort (Priority)AF21010 18 Best Effort (Normal)DE 000 0000 Best Effort (Sub)EXP/LU000 0113 Packet markings WARNING: If a CP does not buy Assured Rate or Real Time traffic classes, but marks traffic as Assured Rate or Real Time, this will result in traffic being dropped. This is different to the behaviour on IPstream. 7

9. BRAS CP Network Core Node (20) Content MSAN Openreach BT Wholesale BTW Backhaul Call Server MSIL Wholesale Broadband Backhaul Management Traffic prioritisation to suit application needs: -Real Time -Assured - Best Efforts Capacity management of backhaul to ensure: -Assured / Real Time traffic guaranteed delivery up to agreed levels - Sufficient bursting capacity for Best Efforts traffic - Higher throughput for Elevated CPs can order per traffic class bandwidth to determine the overall experience of their products 8

10. Downstream QoS at the BRAS Hi weight Med weight Priority Normal Highest priority level Pre-defined queue - CVLAN shaped to specified max. bandwidth, and competes for SVLAN bandwidth with other CVLANs X Best - Effort Use of either priority level or weighting to guarantee bandwidth Real Time Hi weight Priority Normal Highest priority level CVLAN shaped to specified max. bandwidth, and competes for SVLAN bandwidth with other CVLANs X Use of either priority level or weighting to guarantee bandwidth Assured Rate On-demand queue Lo weight Sub- BE Higher weight for Elevated Low High 9

11. Downstream QoS at the BRAS - Technical Proposal for DDQ Achieved with dedicated queue at the BRAS for Dedicated Downstream QoS traffic Uses same packet marking as Assured Rate (Assured Forwarding traffic class) Available at ppp start rather than configured on-demand as Assured Rate Excess Traffic will be dropped rather than forwarded as Best Efforts Hi weight Med weight Priority Normal Highest priority level Pre-defined queue - X Weight set higher for Elevated EUsthan StandardEUs, to give greater share of SVLAN for BE Best-Effort Use of either priority level or weighting to guarantee bandwidth Real Time Hi weight Lo weight Priority Normal Highest priority level End User traffic shaped to specified max. bandwidth. Real Time & Best Efforts only compete for SVLAN resource with other EU traffic Weight set higher for Elevated EUsthan StandardEUs, to give greater share of SVLAN for BE Best-Effort Use of either priority level or weighting to guarantee bandwidth Assured Rate On-demand queue Dedicated Downstream Bandwidth Pre-Defined queue High Low 10 Sub- BE

12. WBC Performance Targets Real Time Packet loss: 0.01% for a peak period of time Assured Rate Session Blocking Ratio: 1% during the busy period Best Efforts Elevated EUA Throughput: Above 3M for 90% of the time during the 3-hour busy period Best Efforts Standard EUA Throughput: Above 2M for 90% of the time during the 3-hour busy period 11

13. WBC Price List 12

14. QoS Pricing Structure Real Time 7p Kbit/s p.m. (indicative) Assured 0p Kbit/s p.m. Best efforts 0p Kbit/s p.m. per mth Basic Traffic 7.934 p per Kbit/s per mth AP Real Time 14.934 p.m. (indicative) Assured 2p Kbit/s p.m. (indicative) Best efforts 7.934p Kbit/s p.m. Current Price Structure Proposed Structure QoS charged independently of Best Efforts 13

15. Q & A 14