vadese vod-nov 2006

8/6/2019 Vadese VoD-Nov 2006

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Video on Dem and over the InternetT r

ends and

cha

ll enges

J uergen Ehr ensberger (HEIG-VD)Andr s Revuelta (EIG)

J ean-Roland S chuler (EIA- FR)

Novem ber 2006


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P ro ject Vadese

Video on Dem and and S ecur ity http: // www .vadese.org

Tw o-years r esearch pro ject 4 r esearch groups from 3 differ ent schools

(Fr ibourg, Geneva, Yverdon) Focuses on the needs of VoD se rvices providers

Quality of S ervice P atching over P eer - to-peer Digital Rights Managem ent


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Video over the Internet

31 October 2006 :S w isscom launches Bluew in TV


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Video over the Internet

J uly 2006 :Deutsche Telekom launches IP TV


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Video over Internet Market studies

IP TV

T e l ev i s i on b r oadcas t ove r t he I n t e r ne t access Wor ldw ide m arket size (Gar tner 2006 )

$870 m illion in 2006 $13 billion in 2010

Video on Dem and D o w n l oad o r s t r ea m i ng o f m ov i es a t any t i m e Wor ldw ide m arket size (iS uppli 2006 )

40 % grow th in 2005 $2 billion in 2006 $13 billion in 2010


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Another m arket study...


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Media distr ibution over the Internet

Media can be transferr ed by dow nload or str eam ing

Dow nload A file is dow nloaded from a se rver to the custom ers equipm ent The m edia can be consum ed only after the dow nload has finished

S i m p l e N o t su i t ed f o r li ve con t en t

Long w a i t i ng t i m e

S tr eam ing

A continuous m edia flow of packets is tr ansferr ed from a se rver to the custom er The custom er consum es the m edia sim ultaneously w ith the tr ansfer

S u i t ed f o r li ve con t en t T echn i ca ll y cha ll eng i ng


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Netw ork scenar io


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Quality of S ervice

The m ain challenge of str eam ing m edia over this Internet is to obtain a sufficient Quality of S ervice :

Q o S i s

t he co

ll ec

t i ve e

ff ec

t o

f

se r v i ce pe r f o r m ance w h i ch de t e r m i nes t he deg r ee o f sa t i s f ac t i on o f a

use r o f a se r v i ce ( I T U - T R ec . E - 800 )


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Measur able per for m ance par am eters

Throughput S peed of the tr ansm iss ion, bits per second r eceived

P acket loss r ate P ercentage of packets lost inside the netw ork

Netw ork delay Delay betw een the sending of a packet at the source and the

r eception by the r eceiver Delay var iation

Changes of netw ork delay betw een success ive packets


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Throughput Media str eam s have an inher ent bitr ate that has to be provided by

the netw orkThroughput r equir em ents

Tr ansm iss ion capacity

5 6 Mb / sHDTVMP EG -4 AVC768 kb / sTV qualityMP EG -4 AVC

1 4 Mb / sTV qualityMP EG -2Bitr ateQualityCodec

13 000 flow s10 Gb / sISP s / Internet130 flow s100 Mb / sEthernet4 flow s3 Mb / sADS L

MP EG - 4 TV flow sCapacityNetw ork


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P acket loss

What happens if ther e is too m uch tr affic in the netw ork? The Internet is a netw ork of tr ansm iss ion links,

connected to routers


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P acket loss

What happens if ther e is too m uch tr affic in the netw ork? Each router r eceives tr affic from sever al input links and

for w ards the packet to output links


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P acket loss

What happens if ther e is too m uch tr affic in the netw ork? If the output link is occupied, packets have to w ait for

tr ansm iss ion in a queue


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P acket loss Tr ansm iss ion queues on routers ar e causing

packet loss and delaysMeasur em ent over low- capacity access links

Up to 5% packet loss20 m s one-w ay delay

InternetISP

Home network

ADSL (3Mb/s)

HEIG-VD

Access 100 Mb/s

Packet loss, delays

Router


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Effect of packet loss on video quality

Exam ple: 1% loss MP EG -2

No e

rro

r conceal

ment

Exam ple: 5% loss MP EG -2

No e

rro

r conceal

ment


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Effect of netw ork delay

Netw ork delay is not cr itical for non- interactive applications

Typically netw ork delay is below 1 seconds

Use r m ay toler ate sever al seconds of delay

Possible problem s Rober to Baggio Effect Channel sw itching delay


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Delay var iation

Media playback r equir es a constant flow of data The packets of the m edia flow exper ience differ ent netw ork delays

A playout buffer com pensates the delay var iations H

alf- fill

ed upon

sta

r t o

f the

trans

m iss

ion

( B

u ff

e r i ng

.. . )Incr eases netw ork delay

Delay var iations should be sm all to keep playout buffer sm all


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Curr ent challenges

Insufficient QoS over ADS L and CaTV Overdim ensioning or VDS L QoS m echanism s in the ISP netw ork

QoS m echanism s on user s S et-Top BoxHigh cost for str eam ing individual flow s

P atching of video flow s P eer - to-peer distr ibution of flow s

Digital Rights Managem ent


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Overdim ensioning of the access link

ADS L link w ith 3 Mb / s MP EG - 4 AVC video w ith TV quality at 768 kb / s

Additional traffic (Web, E- m ail, dow nloads) m ay deter iorate the video quality

Dynam ic overdim ensioning ISP dynam ically incr eases ADS L capacity

dur ing video stream ing S hould provide sufficient capacity for

video and additional dow nloadsP roblem : tr affic dem and adapts to available

capacity

Very High Bitr ate DS L (VDS L2) P rovides capacity of 20 Mb / s (over 1500 m ) Allow s sim ultaneous tr ansm iss ion of 2

HDTV channels P roblem : high investm ent r equir ed to

upgr ade the access netw ork


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QoS m echanism s in the ISP netw ork

Even over ADS L, a sufficient QoS can be provided using QoS m echanism s Idea: give video flow pr ior ity over other tr affic

Video flow gets sufficient capacity to avoid packet loss on the ADS L link Other tr affic (Web, dow nload) is still possible, but slow er


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QoS m echanism s in the ISP netw ork

Even over ADS L, a sufficient QoS can be provided using QoS m echanism s Idea: give video flow pr ior ity over other tr affic

Video flow gets sufficient capacity to avoid packet loss on the ADS L link Other tr affic (Web, dow nload) is still possible, but slow er


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QoS m echanism s on user s S et- Top Box So lut ion de ve lope d in Va de se Modifications of the access netw ork ar e costly S ervice providers do not ow n the access netw ork How can a se rvice provider offer sufficient QoS ?

Use QoS m echanism s on the S et-Top Box Has to control tr affic a ft e r it has crossed the ADS L link!


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QoS m echanism s on user s S et- Top Box

Non-video tr affic m ainly uses TCP TCP adapts to netw ork congestion, detected by packet loss

Control queue length on ISP router from S et- Top Box S plit Advanced Queue Managem ent


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High cost for Video-on- Dem and In VoD, custom ers access videos at differ ent m om ents The sim ple approach to star t a new flow for each use r is not

econom ical

Exam ple : access link at 1 Gb / sOnly 200 sim ultaneous HDTV flow s (at 5 Mb / s)Cost of $1 per video, only for tr ansm iss ion


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Near Video-on- Dem and w ith Multicast Solution

A new flow for the sam e video star ts every n m inutes S im ilar to a TV broadcast that r epeats every n m inutes Flow is efficiently tr ansm itted via m ulticast

Multicast is only feasible for netw ork oper ators


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Video patching w ith P eer - to-peer So lut ion de ve lope d in Va de se Allow s true Video-on- Dem and Can be used by se rvice providers w ithout their ow n m ulticast netw ork Idea of patching:

A custom er w ho alr eady r eceives a video can r elay the flow to a new custom er

The m

iss ing part of the video is te

mpo

ra

rily

patched

fro

m the se

rve

r


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True Video-on- Dem and w ith Multicast Possible alternative to P eer - to-peer tr ansm iss ion Com bines Multicast and P atching to achieve true Video-on- Dem and Solution

A new m ulticast flow for the sam e video star ts every n m inutes When a new custom er arr ives, it joins an existing m ulticast sess ion The m iss ing first m inutes of the m ovie is patched by a shor t- lived patching flow

Joins multicast


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Conclusion

P ro ject Vadese - V i deo on D e m and and S ecu r i t y Focuses on the needs of VoD se rvices providers

Quality of S ervice P atching over P 2P Digital R ights Managem ent

Technologies w ill be integr ated in a S et- Top Box Possible valor izations

Follow- up pro jects w ith comm ercial par tners Intellectual proper ty Comm ercialization of som e of the technologies

vadese vod-nov 2006

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