A Method for Extremely Scalable and Low Demand Live P2P Streaming based on Variable Bitrate

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P2P Streaming: Models and Problems

M.Zhanikeev -- [email protected] -- Extremely Scalable ... Live P2P Streaming based on Variable Bitrate -- http://tinyurl.com/marat131205 --- 2/25...

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P2P Streaming Models

Share

…

Content Provider (origin)

P2P Network

1. BitTorrent model 11,aka the pull paradigm◦ many software products

-- all based on defaultBitTorrent

2. substream model 10,aka the push paradigm◦ several existing services

07 08 09◦ not limited to P2P

networks, also work inclouds 03

03 myself+0 "Multi-Source Stream Aggregation in the Cloud" Wiley Book on Advanced Content Delivery ... Clouds (2013)

08 K.Park+4 "An Analysis of User Dynamics in P2P Live Streaming Services" ICC (2010)

09 C.Wu+2 "Diagnosing Network-wide P2P Live Streaming Inefficiencies" IEEE INFOCOM (2009)

10 Z.Li+4 "Towards Low-Redundancy Push-Pull P2P Live Streaming" QShine (2008)

11 C.Stais+1 "Realistic Media Streaming over BitTorrent" Future Network and Mobile Summit (2012)


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P2P Substream Method

P2P Connection

…. ….

….

….

• basic idea: shakehands thanuse contin-uously


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Problems and Solutions

• quality management

1. BitTorrent: nothing2. substream: parent/child re-election

• overhead1. BitTorrent: RTT per piece2. substream: switching time at re-election

• optimization1. BitTorrent: nothing, but some selection algorithms2. substream: multihop optimization is possible -- scheduling and flow problems

• the biggest problem: data unit has constant size!


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P2P Streaming: Social Features


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P2P Streaming: Social FeaturesTraffic flow

Scal

e

…

…

…

…

• note: P2P delivery network is not reallya tree

• reality shows that your remote peers arepower-law distributed in throughput◦ gets harder to find good peers with longer

lists


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Bitrate: CBR, VBR, SVC


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CBR, VBR, SVC• VBR and SVC are both part of ITU-T H264 12

• VBR: really extreme variation in throughput

• SVC: smoother distribution 13, with some control over smoothness 14◦ why: SVC is based on hierarchy of layers which can be moved around within GOP

GOPBlock

Time

Fra

me

size

GOPBlock

Time

Fra

me

size

CBRVBR

GOPBlock

Time

Fra

me

size

SVC

12 "Advanced video coding for generic audiovisual services" ITU-T Recommendation H.264 (2012)

13 R.Kusching+2 "An Evaluation of TCP-based Rate-Control ... Streaming of H.264/SVC" ACM SIGMM MMsys) (2010)

14 M.Fidler+3 "Efficient Smoothing of Robust VBR Video Traffic ... Slice-Based..." CCNC (2007)M.Zhanikeev -- [email protected] -- Extremely Scalable ... Live P2P Streaming based on Variable Bitrate -- http://tinyurl.com/marat131205 --- 9/25...

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Bitrate Models and Distributions• real traces from 15

• VBR versus single-layer SVC

0 20 40 60 80 100Time sequence

0

4

8

12

Fram

e siz

e (k

b)

VBRSVC

0 20 40 60 80 100Distribution sequence

0

4

8

12

Fram

e siz

e (k

b)15 P.Seeling+2 "Network Performance Evaluation with Frame Size and Quality Traces ..." IEEE Comm. Surveys... (2004)


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The Proposal: VBR Subtreams


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Recap: The Objectives

.The Main Objective is.....

.... to build a method which canadapt to to any peer distribution in realtime

• VBR is fixed, no control parameter

• SVC can be controlled by switching between encoders

• ultimately: raw manipulation by shifting SVC blocks around the GOP

• ideal success: distribution of throughput in peers = distribution offramesize in GOP


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Proposal: Substream Design• simple: pick a frame position in GOP and assign it to one peer

◦ positions: 1st, 2nd, ....

• expected outcome: since 1st frame is normally the largest in GOP, that peershould be able to support high throughput◦ by extension, most other peers carry much lower load◦ size of GOP = number of peers, by design

GOPBlock

Time

Fra

me

size

GOPBlock

Time

Fra

me

size

CBRVBR

GOPBlock

Time

Fra

me

size

SVC


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Proposal: Dynamics

Parent A Client

Parent B

Connection close detected

Close connection Pick a better candidate

Bigger frames (GOP pos x)

Periodic check/update

Bigger frames (GOP pos x) Smaller frames (GOP pos y)

Re -order parents

Only for changed

frames/parents/GOP pos

Failed to receive

• traditional substream:find a new peer for a substream

• proposed: swap framepositions between two peers◦ peers are initially selected

close to the expecteddistribution, so no newpeers are necessary


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Simulation


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Simulation: Models and Parameters

0 10 20 30 40 50Distribution sequence

0

0.2

0.4

0.6

0.8

1

Val

ue

VBRSVCCBR

1. pick VBR I-Frame size asset it to 1

2. pick I-Frame size of SVC as afraction of 1

3. pick frame size of SBR as afraction of 1

4. use these fractions asparameters


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Simulation: E2E Throughput Model• throughput variation is modeled as drops in throughput• longer paths experience more drops (not deeper!, more in number)

• a parameter defines the range of drop probabilities for sampling one's peers

100%

0%

Throughput

Time

Time slot

SimulationparameterSimulationparameterSimulation

parameters


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Results : Freeze Time

0 0.3 0.6 0.9 1.2 1.5CBR level

0

1

2

3

4

5

6

7

Ratio

of V

BR/C

BR a

nd S

VC

/CBR

(fre

eze

time)

VBR to CBRSVC to CBR

x=0.05

x=0.2 x=1

y=1

• simple lesson: framesizedistributions are good, as longas they are not extreme

• CBR can outperform VBR/SVConly below frame size of0.2 -- 1/5th of VBR I-Frame)


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Results : Gain (social)

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1Normalized lower throughput

0.9

1.1

1.3

1.5

1.7

1.9

Thro

ughp

ut g

ain

(hig

her /

low

er) (

kbps

)

Slow peers

• viewpoint: how much can auser benefit from a VBR/SVC substream design?

• test various peer distributionsand find out

• gain: best SVC/VBRthroughput divided by thenumber of CBR


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Wrapup

• VBR/SVC substream design create a sociallyadequate method◦ after all, is it your fault that your 3G shapes your throughput?

• VBR/SVC substream design has to be a clean slate -- frame positionassignment is proposed

• results show thatSVC is preferred because its framesize distributionis smoother◦ even more becuase the distribution can, in theory, be controlled


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That’s all, thank you ...


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The PUSH vs PULL Argument

Server Client

……

Server Client

……

Pull

Push

• mathematical argument in[03]

• overhead =RTT for each piece

• overhead can be overcomeonly by drasticallyincreasing the number ofremote peers --swarming


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Reference: Average Throughput

0 10 20 30 40 50 60 70CBR Frame Size (kb)

-1.5

-1

-0.5

0

0.5

1

1.5

2

2.5

3

Ratio

of a

vera

ge th

roug

hput

(-lo

g(1/

y) fo

r y <

1)

VBR/CBRSVC/CBR

CBR < VBR

VBR < CBR

VBR < 0.5 * CBR

• unit I-Frame size is50kb

• known fact: VBR/SVC cansupport the same qualityat 1/2 of CBR's throughput 15

• 1/2 of CBR's throughput is atabout 20kb of CBRframesize

15 P.Seeling+2 "Network Performance Evaluation with Frame Size and Quality Traces ..." IEEE Comm. Surveys... (2004)


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Features: Taxonomy• is your data unit regular? and can it be adaptive in realtime?

BLOCK

GOPFRAME

Content

Fixed Regular

FixedIrregular

AdaptiveIrregular

This method

FRE AIR

FIRBLOCK

GOP

FRAME


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SVC in P2P: Disclaimer

• SVC is considered for P2P in literature

1. BitTorrent with variable-size pieces 042. BitTorrent pieces as multiples of GOP 053. optimization for SVC layer repacking in small scale streaming tool called SPPM

(Stanford)

◦ assignment by frame size positions is still the unique contributions◦ socially, the proposed method will scale while SPPM will not

04 N.Capovilla+4 "...Distributing Scalable Content over P2P Networks" MMEDIA (2010)

05 P.Baccichet+3 "Low-delay Peer-to-Peer Streaming using Scalable Video Coding" Packet Video (2007)


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[01] R.Buyya+3 (2008)Content Delivery NetworksSpringer LNEE, vol.9

[03] myself+0 (2013)Multi-Source Stream Aggregation in the CloudWiley Book on Advanced Content Delivery ... Clouds

[04] N.Capovilla+4 (2010)...Distributing Scalable Content over P2P NetworksMMEDIA

[05] P.Baccichet+3 (2007)Low-delay Peer-to-Peer Streaming using Scalable Video CodingPacket Video

[06] C.Gurler+2 (2012)Variable chunk size ... and ... window for P2P streaming of scalable videoICIP


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[07] B.Li+5 (2008)Inside the New Coolstreaming: Principles, Measurements and PerformanceImplicationsIEEE INFOCOM

[08] K.Park+4 (2010)An Analysis of User Dynamics in P2P Live Streaming ServicesICC

[09] C.Wu+2 (2009)Diagnosing Network-wide P2P Live Streaming InefficienciesIEEE INFOCOM

[10] Z.Li+4 (2008)Towards Low-Redundancy Push-Pull P2P Live StreamingQShine

[11] C.Stais+1 (2012)Realistic Media Streaming over BitTorrentFuture Network and Mobile Summit


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[12] (2012)Advanced video coding for generic audiovisual servicesITU-T Recommendation H.264

[13] R.Kusching+2 (2010)An Evaluation of TCP-based Rate-Control ... Streaming of H.264/SVCACM SIGMM MMsys)

[14] M.Fidler+3 (2007)Efficient Smoothing of Robust VBR Video Traffic ... Slice-Based...CCNC

[15] P.Seeling+2 (2004)Network Performance Evaluation with Frame Size and Quality Traces ...IEEE Comm. Surveys...

[16] J.Surowiecki (2004)The Wisdom of CrowdsDoubleday


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A Method for Extremely Scalable and Low Demand Live P2P Streaming based on Variable Bitrate

Technology

Transcript of A Method for Extremely Scalable and Low Demand Live P2P Streaming based on Variable Bitrate