BT multicast plans 2007

Consult21 1Information is subject to change and is for discussion purposes only. Any dates/timings are the current anticipated timescales and may be subject to

change.Broadband

Multicast

27 February 2007

Broadband Working Group Presentation


change.Broadband

Technical Roadmap-Q2 Launch Q2 Q4 Q6 Q8

Beta Trial

WBC as per product Spec.

Improved control over line stability/speed

Multicast – IGMP to AP

1024 upstream on ADSL2+

Time table shows Quarters before and after Launch

ADSL2+ Annex M

Multicast – IGMP to CMSAN


change.Broadband

TR-101 REFERENCE MODEL

Regional BroadbandNetwork

Access Network

AccessNode

(DSLAM)

AccessLoop

MDFEthernet

AggregationIP

BBNetworkGateway

L2TS

IP - QoS

L2TP

Customer Prem. Net

CPE

NSP1

ASP1

A10-ASP

A10-NSP

U

User1

User2T

NIDNSP2

A10-NSP

IP - QoS

A10-NSP

V

NSP/BB Network Gateway

Aggregation Network

ATM-Ethernet interworking

VLAN handling Security QoS Multicast / IGMP OAM

ATM-Ethernet interworking

VLAN handling Security QoS Multicast / IGMP OAM

Ethernet/VLAN aggregation QoS OAM Resiliency

Ethernet/VLAN aggregation QoS OAM Resiliency

PPPoE and/or IP services

Bandwidth/QoS policy enforcement

Security Multicast control OAM

PPPoE and/or IP services

Bandwidth/QoS policy enforcement

Security Multicast control OAM

In 21CNcontext, this could be for primary line voice (H.248) transport to the softswitch

This traffic is analogue POTS on the copper so doesn’t need shaping into the DSL payload

Other traffic is via the BNG hierarchical scheduler to ensure QoS & correct provisioning

In 21CNcontext, this could be for primary line voice (H.248) transport to the softswitch

This traffic is analogue POTS on the copper so doesn’t need shaping into the DSL payload

Other traffic is via the BNG hierarchical scheduler to ensure QoS & correct provisioning


change.Broadband

*

WBC Architecture

CPEU

BRAS

Broadband Edge Aggregator

Ethernet*

Aggregation Point(20 Nodes)

*

*

MSAN(5500 Nodes)

DSL AccessADSL2+single VCPPPoE or oA(oE only for multicast) dedicated to EU

Access Aggregationcontended, shared amongst multiple EUsPPPoE with IA

Aggregation PointPhysically shared, logically separate per CPComprehensive QoS features

Customer Access linksuncontended, dedicated to each Communications Provider. L2TP or PTA


change.Broadband

TR-101 : QUALITY OF SERVICE OPTIONS

DiffServ based IP QoS at the Routing Gateway and the BNG.

QoS models :

Partitioning of bandwidth among the BNGs

Based on business or application characteristics

Each BNG controls its partition -> inefficient use of capacity

Distributed precedence and scheduling

Ethernet QoS in the Access/Aggregation Network

Lower classes will be dropped under congestion

Fairness between classes but NOT amongst users within a class

Hierarchical Scheduling on the BNG

A sequence of scheduling steps to model downstream congestion points (BNG port, Access Node uplink and DSL synch rate)

Can be used in combination with the above for per user/session control


change.Broadband

BRAS downstream QoS - SVLAN view

Realtime

Assured rate (ADQ)

Best-Effort

SVLAN shapedSVLAN shapedto specifiedto specifiedbandwidthbandwidth

• Guaranteed access to SVLAN

• Administrative maximum set for ADQ CAC process

• Guaranteed minimum bandwidth, with access to unused Realtime & ADQ allocations

• Arbitrary mix of Priority & Normal traffic, depending on EU traffic patterns

• Priority access to SVLAN for guaranteed bandwidth & low jitter

• Maximum bandwidth set to protect other classes

Bandwidth poolsBandwidth pools

Realtime

Assured rate (ADQ)

Best-Effort

SVLAN shapedSVLAN shapedto specifiedto specifiedbandwidthbandwidth

• Guaranteed access to SVLAN

• Administrative maximum set for ADQ CAC process

• Guaranteed minimum bandwidth, with access to unused Realtime & ADQ allocations

• Arbitrary mix of Priority & Normal traffic, depending on EU traffic patterns

• Priority access to SVLAN for guaranteed bandwidth & low jitter

• Maximum bandwidth set to protect other classes

Bandwidth poolsBandwidth pools


change.Broadband

BRAS downstream QoS - CVLAN view

Realtime

Hi weight

Lo weight

Assured/ADQ

Priority

Normal

Highest priority level

Rate-limit

Rate-limitCVLAN shaped to specified max. bandwidth, and competes for SVLAN

bandwidth with other CVLANs

X

• Weight set higher for Elevated EUs than Standard EUs, to give greater share of SVLAN for BE

Best-Effort

Use of either priority level or weighting to guarantee bandwidth

Realtime

Hi weight

Lo weight

Assured/ADQ

Priority

Normal

Highest priority level

Rate-limit

Rate-limitCVLAN shaped to specified max. bandwidth, and competes for SVLAN

bandwidth with other CVLANs

X

• Weight set higher for Elevated EUs than Standard EUs, to give greater share of SVLAN for BE

Best-Effort

Use of either priority level or weighting to guarantee bandwidth


change.Broadband

*

WBC Multicast VLAN Architecture

CPEU

BRAS BEA

Ethernet*


*

*

MSAN(5500 Nodes)

• Multicast in IPoE • BB & IGMP in PPPoE• 1 VC

• Multicast in IPoE • Snoop IGMP in PPPoE • 1 VC

• Terminate PPPoE• Terminate IGMP• Re-profile EU


change.Broadband

*

WBC Replication Points

CPEU

BRAS BEA

Ethernet*

Potential Multicast Replication Points


*

*

MSAN(5500 Nodes)


change.Broadband

Multicast Issues to Consider

21C

Very large L2 domains with multiple tiers

Large number of possible L2 replication points

Use tunnelling as well as routing in the L3 domain

Routers not currently multicast enabled

Have to balance the efficiency of auto-configuration via PIM against stability, management control and the ability to do troubleshooting

IGMP snooping, querying and reporting can produce a significant load on network elements

Need to protect network elements against surges in signalling traffic

Typical CP Requirement

Large number of channels…

Viewing still concentrated in a very small number of channels

The 5 Terrestrial channels still dominate viewing numbers

Channel changing will be correlated in time to a significant degree

Could have up to 500 viewers on an MSAN watching the same programme

Outside the 5 channels, numbers per MSAN per programme will be very much lower

May need a tiered solution….


change.Broadband

Phase 1 Multicast Architecture

Multicast across WBC networkIGMPv2 joins to BRASStatic configured Multicast between BEA to cMSANStatic Multicast Routing


change.Broadband

Phase 2 Multicast Architecture

MSAN

BRAS

*

*

*

AMSAN

Dynamic joins via IGMP snooping

Static replication

PIM-SM or SSM, not DM

Dynamic joins via IGMP

Green IGMP requests suppressed

Red IGMP reports supressed

Dynamically send newly requested streams

Dynamic joins via IGMP

Black IGMP reports suppressedNo green

IGMP queries

- Mixture of statically configured and dynamic paths to get a scalable system – BW and control - Static paths are end to end or partial - Need to optimise where paths, requests, reports and queries originate/terminate

*


change.Broadband

Multicast CAC

CMSAN

BRAS

STB

CPE

IGMP

CACM/C

HeadEnd

Multicast Stream

IPoE Multicast

IGMP/PPPoE

Multicast VLAN

Broadband VLAN

Video Play Request

Multicast Join Authorisation

M/C reserve

M/C granted

D/S line rateA/S statusM/C status

IGMP

CP BTW CP

IGMP signals M/C join to BRAS which re-profiles EU

CAC function will have to maintain state on EU multicast session so that a subsequent request for an advanced service takes into account the bandwidth already in use for multicast

BB Customer Reporting (BBCR)

2 logical interfacesover single VC


change.Broadband

Multicast Proof of Concept

PoC under construction using existing models at Adastral Park Verify vendor capability including interworking

Explore multiple options - Identify technical architecture

Technology Up-skilling

Develop Showcase Capability

Capability for CP’s to take part in PoC to interwork CPE and Head end equipment


change.Broadband

PoC Target Network

Home Access Metro CP

Application / Content

BRAS

Eth SWRouter

Services(RADIUS, ADQ etc.)

Model IP Network

Eth SWRouter

Adastral IP Network

PC

STB

CPE Router

Test Content

Router

(PIM)

MSAN

GE

BT multicast plans 2007

Technology

Transcript of BT multicast plans 2007