Examining the Network Requirement for the delivery of Optimum

© 2006 Cisco Systems, Inc. All rights reserved. Cisco Confidential 1


IPTV networks and Quality of Experience

Nick FielibertCTO Europe & APACScientific –Atlantaa Cisco Company


End User Experience,A Key Ingredient Of IPTV Success


Video End User Quality Of ExperienceRelated Standards & Efforts

IPTV/Telco RelatedITU-T IPTV Focus Group, SG 9, 12, 13 & 16ATIS IIFDSL Forum TR-126DVB-IPI (ETSI TS 102 034)Media Delivery Index (RFC 4445)

DVB/Broadcasting RelatedSMPTE Technical StandardsEBU Technical DocumentsDVB Forum (ETSI TR 101 129, TS 101 154, etc…)ITU-R Broadcasting Services BT seriesPerceptual Metrics: V-Factor, MPQM, Video-MOS, …


IPTV End User Quality of ExperienceKey Requirements

1.Service Availability & Reliability Limited Frequency & severity of impairments

2.Content Quality & ScopePremium Content, live events, exclusivity, VoD catalogue

quality etc..

3.Content Definition & Resolution D1, HDTV, Dolby Surround, AAC, etc…

4.Customer Care & Management: Time & way to solve end user video related problems

5.IPTV Service Usability Easiness & friendliness of service discovery & selection

interfacefoundation of a new TV viewing experience

6.Channel change time Satellite, Cable and DVB-T Benchmark


A/V Encoding

FEC

EPG info qualityGUI design

Network ElementsDelay, jitter,

packet ordering

VODServer load distribution

Oversubscription management

Channel Change, packet retransmission

MetroAggregation

Network

IPTV QoE In The End To End Model

VoD Servers

Homegateway

Homegateway

Homegateway

Homegateway

Homegateway

Homegateway

IP/MPLS Core

SuperHeadEnd

LiveBroadcast

& VoDAsset

Distribution

Central/EndOffice

VoD Servers

IRT/RTE

IRT/RTE

District Offices

Home networkingDelay, jitter, packet

ordering

STBA/V decode buffers,

Lip sync,Output Interfaces, FEC

A/V Encoding

Highlights of the main areas

Central/EndOffices

MW Servers

DSL

Fiber


Delivering Optimum IPTV QoEContrasting Architectural Approaches

L2 VPLS

Centralized• Agg: L2 bridging all

services• QoS: Per sub for all

services

Distributed• Agg: H-VPLS for all

services• QoS: Per sub for all

services

Service Optimized IP NGNAggregation:

• L1, L2, L3 based on service

• Instrumentation & control

QoS: • Aggregate for

applications• Per sub for transport

L2 Bridging

L2 & L3

VoDServers PPPoE

BRAS

IP / MPLSCore

Voice

Video

H-VPLS

L2 QoS

L2 QoS

L2 QoSAccess

All services per sub QoS, H-VPLS Aggregation

Central L3

L3

L3

L2 VPLS L3

L3

L3

L3

L2 Bridged

L3 for Application Service

L2

VoDServers

Central L3 and per sub

QoS

Access

IP / MPLSCore

VoDServers

BRAS

IP / MPLSCore

L2 QoS

L2 QoS

L2 QoSAccess

Per service QoS, CAC and L3 aggregation for

voice/video

Per-sub QoS and EomPLS for

transport services

MPLS PE

Dist Router

L2-HIS/BizL3 - Voice / Video


Delivering Optimum IPTV QoENetwork Linkages for Carrier-Class Video Operations

• Redundant Broadcast Sources• Subscriber STB Load sharing across dual trees (localized content)• “Anycast” enables Dynamic Failover - merges trees into one trunk• Enabled with Video Headends

MetroAggregation

Network

MetroAggregation

NetworkIP/MPLS

Core IP/MPLS

Core

National Video Head

EndLiveBroadcast

& VoDAsset

Distribution

PE-AGG

VOD Servers

VOD Servers

VOD Servers

VOD Servers

PE-AGG

Local Broadcast Insertion (eg PEG)

IRT/RTE

IRT/RTE

IP Routing Anycast

IP Routing Anycast

Benefits


Protecting IPTV Quality of ExperienceL3-Based Architectures Enabling High Service Availability

Layer 3 Multicast Architecture BenefitsProvides consistent convergence <1s in all scenariosAnycast for dual redundant headend

H-VPLS transport Architecture BenefitsMPLS FRR for link failures for <50msBUT failure of Aggregation Node, Designated Router, Source, or Headend result in slow STP or IGP based convergence

Link in metro

NodePE-AGG

DR/Querierat NPE

H - VPLS ~5s

Impact (#subs) 10,000 50,000 100,000 1,000,000

Layer 3 <1s <1s NA <1s

Impact (# subs) 10,000 50,000 NA 1,000,000

Source at National HE

>2-3s<1s 2-3s


Protecting IPTV Quality of ExperienceThe Need for Video Admission Control• What happens when demand exceeds design assumptions?

Network design based on some allowed blocking factorBlocking factor based on peak concurrency rate of subscribers at the finite take rate of the service

What if take rate of service is higher than forecast?What if HDTV, TVoD is accelerating faster than forecast?What if peak concurrency is higher than forecast?

• Without a “Graceful Busy Signal” for video service, excess streams result in degraded video for Many

Oversubscription leads to random packet loss for many!No more than one artifact per 2 hours => 10-6 PLR !!Loss mean visible artifact on subs’ TV for a varying amount of time

0.5 % Packet Loss


PE-AGG

BPM

N-PE

RSVP-CAC

VOD Request

Deny or Admit

DSLAM

COPS

CAC required to guarantee End User experienceIntegrated Video CAC approach combines two methods:On-path RSVP-CAC for AggregationOff-path CAC based on Broadband Policy Manager (BPM) for DSL line

VOD stream will be denied if business rules of either failPrioritize blocking of Free VOD vs. Pay VOD

Multicast CAC optional11

22

33

44

55

6622

22

22

Protecting IPTV Quality of ExperienceIntegrated Video CAC


Content is key to QoEBy Offering a differentiated experience – E.g. content, HD

Source: McKinsey Analysis, Fastweb Company Report

Customer base evolution in Thousands of IPTV customers

Average quarterly growth

3Q

130

2Q

129

272420

62

4Q

38

4Q 3Q

108

2Q1Q

2003

88

1Q

2004

2Q

133

1Q

2005

133

4Q3Q

2002

130<1%<1%

16%16%

37%37%

FW starts distributing Sky soccer package, being the only alternative to

satellite

Competition for soccer content kicks in:

Exclusive Content (e.g. Football) High Definition

http://www.fastweb.it/


African

ABN America - $14.99/mo.

Armenian

Armenia TV - $14.99/mo.

Arabic

15 channels - $39.99/mo.

Al Jazeera Kuwait TV

Chinese


Farsi


French

3A Telesud - $14.99/mo.

German

Polish

1 channel - $14.99/mo.

Greek


Israeli

Israeli Network - $19.99/mo.

Italian


Japanese

TV Japan - $25.00/mo.

Korean



Portuguese Russian South Asian Tagalog Urdu

TV Globo - $19.99/mo. 2 channels - $24.99/mo. 6 channels - $49.99/mo. 1 channel - $14.99/mo. 3 channels - $34.99/mo.

The high price of these offerings demonstrates the value to niche consumers.

Content is key to QoEGrasp revenue possibility created by the Long Tail


Picture Quality correlates very strongly with QoED9054 HD H.264 Encoder Video Quality Improvements

CBR Bit rate

TimeApril 06

10

June’ 06 Dec06/Feb07 April/07

8.8

8.2

7.6

7

Q4/ 07

4

IBC’ 06

HD needs to stay HD!No reduction of resolution and Color DepthNo massive pre-processing for sharpnessBitrate reductions

PAFFDynamic & hierarchical GOP features Optimized HP 8x8 features

6


Protecting IPTV Quality of ExperienceVisual Quality Experience (VQE) Technology

Real-time video error repair

Eliminates effects of uncorrelated bit errors on individual DSL linesLocal re-transmission of dropped IP packets to STB in Sub-100ms

Scalable, standard-based fast channel change

Maintains consistent user experienceSub-second channel change time

Diagnoses problem areasMonitoring and reporting of faults per DSL line above threshold

Complementary to FECRepairing

Multiple Uncorrelated Dropped Packets


VQE—Video Error RepairConditions DSL Lines for Advanced Video Services

Reduces SP OpEx and Customer Churn—Avoids costly help desk callsEnhances Customer Video Experience Quality—Delivers better video

STB Detects

packet lossSTB DSLAM

Sends standards-

based message to

VQE

iFrame pb p …. iFrameiFrameiFrame pb p …. iFrameiFrame

VQE Re-transmits

missing packet(s)

STBRe-sequences video stream

Error repair done in less than 100 ms


Role of Middleware in QoE: The Enabler

SHOW a family watching tv

EnablesRevenue producing IPTV services Differentiation for service provider: Perquisite to competeConsistent and extensible consumer experience interoperability of systems components Compelling GUI Roadmap for current and future rich media development Linkage of rich media with consumer


Customer ExperienceCustomer Experience

ROBUST COMPELLINGFLEXIBLE


Key attributes of Successful MiddlewareDrives Service Provider SuccessDrives Service Provider Success

Operational RequirementsOperational

RequirementsSCALABLE AGILE MANAGEABLEUPGRADIBLECOST EFFECTIVE

InteroperabilityInteroperability

OPENINTEGRATEDPORTABLE

OPENINTEGRATEDPORTABLE


Key attributes of Successful Middleware

ROBUST – Highly Available and Reliable COMPELLING – A rich User Interface that is interactive and customizableFLEXIBLE – To support the specific needs of different service providers

ROBUST – Highly Available and Reliable COMPELLING – A rich User Interface that is interactive and customizableFLEXIBLE – To support the specific needs of different service providers

Customer ExperienceCustomer Experience



Drives Service Provider SuccessDrives Service Provider Success


STB Network BufferDe-jitter

Re-order FEC/re-xmit

STB Video Decode Buffer

CBR/VBRPackets

Video data

Audio data

STB Audio Decode Buffer

Transport Dem

ux TV

Video

audio

1. Packets enter the network buffer 2. Transport

Demux separates video

and audio3. When buffer is ~½ full,

Audio and Video Decoders play from Buffer

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

Simplified STB data flowPrivate

dataTo CPU


Protecting IPTV Quality of ExperienceFast Channel Change & Dynamic Multicast

Channel Change Latency Factor

% total budget

Delay for Mcast Stream to Stop from DSLAM 4%

4%Dynamic Multicast Set Up Delay 6%

8%I-Frame Delay*depends on compression 39%

39%

Multicast Join for New Channel

Jitter Buffer Fill

MPEG Buffering *depends on STB & compression

Channel Change TimeT=0

Common misconception :IP multicast causes slow channel change.

Main culprits:Waiting for the Next I-FrameMPEG buffering (AVC)

500 ms or greater*

50 ms

50 ms

500 ms or greater*

75 ms

100 ms


* Full frame of integrated video content

Old ChannelVideo Stream

New ChannelRequest

VQE Technology Bridges Multicast Join Delays<1 second to Complete Channel Change

New ChannelMulticast Join

(VQE StopsUnicast)

1-5 Seconds without VQE

< 100ms

New ChannelUnicast

from VQE

STBVQE

Scalable Standard-based Rapid Channel ChangeMaintains the Channel Surfer’s Experience

*

Cisco 7600


STB Network BufferDe-jitter

Re-order FEC/re-xmit

STB Video Decode Buffer

CBR/VBRPackets

Video data

Audio data

STB Audio Decode Buffer

Transport Dem

ux TV

Video

audio

1. Packets enter the network buffer

2. Transport Demux

separates video and audio

3. When buffer is ~1/4 full, Audio and Video Decoders play from Buffer at 80% speed

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

CBR/VBRPackets

STB data flow with early start

4. When buffer is ~1/2 full, Audio and Video Decoders play from Buffer at full speed


MPEG4 IPTV with unicast buffer fill and early startearly start S-A concept – works in either, xDSL, FTTH, Lab

Action unit time total time Send IGMP leave <10 msSend IGMP join <10 msInterleaved D-server join <10 msDSLAM gets leave <10 msDSLAM gets join <10 ms ~20 msDSLAM switches streams 30 ms ~50 msDSL (including FEC) ~10 ms ~60 msCached PAT/PMT 0 ms ~60 msBuffer

Wait for CA <50 msI-frame (first frame) <100 msDe-jitter <50 msMPEG buffer (1x with early start )

500-800 ms 560-860 ms Selective Retransmittion <200 ms 760-1060 ms

Decode <50 ms 810-1110 ms


SummaryIPTV: From Service Provider To Experience Provider

Video & IPTV: Foundation Of Experience ProviderWith Video (HDTV, On Demand), Quality Of Experience Matters

Quality Of Experience : impacting Telco’s profitabilityReducing SP Opex & Customer ChurnAvoids Costly Help Desk CallsDifferentiating Beyond Price & Content
