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Home Boxes Support for an Efficient Video on Demand
Distribution
Soraya Ait Chellouche, Daniel Négru, Yiping ChenCNRS LaBRI Lab. – University of Bordeaux 1, France
Willy AubryVIOTECH Communications SARL
Supported by
ALICANTE (MediA Ecosystem Deployment through Ubiquitous Content-Aware Network Environments)
EU FP7 in ICThttp://www.ict-alicante.eu/
Outline
Problem statement System architecture Popularity-based replication Server Selection Strategy Performance evaluation Conclusion and Future work
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Problem Statement
Context Continuous Video Services Popularity The important cost of video services End users’ contexts heterogeneity
Challenging issues Scalability & cost optimization Reliable services High quality contents
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Replication
Common technique to improve service scalability and reliability
replicate contents among multiple geographically distributed servers bring them closer to end users
Tow issues How to replicate the contents over servers Server selection issue => How to designate
the “best” server ?
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
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Content Delivery Networks CDN Large number of servers/caches distributed
through the network + quality guaranties - cost
P2P approach Build overlays among receivers to distribute and
share video contents + scalability and low cost - lack of control, peer churn, unfairness
system saturation and poor quality
Video Distribution Systems
11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
System Architecture
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Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
11/06/2011
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Popularity-based video placement Offline placement : during the off-peak hours
The frequency of a video in HB caches depends on its
popularity
Video popularity fits
the zipf-like distribution
Video frequecy :
System cost : HB overlay hit ratio :
Only the most popular videos are cached in the HB
overlay
Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
11/06/2011
Anycast Server selection strategy Objectives
Optimize the network and servers’ resources Maximize the user satisfaction
Two level filtering Policy-based filtering: matching between
User context (user language, device resolution, access network bandwidth, etc.)
Video parameters (language, resolution, bitrate, etc.)
Metrics-based filtering Server load Server-to-client delay
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Metrics-based filtering
Probing phase
Server selection
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
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Simulation environment 1/2 Under NS 2 The network topology is derived from the Survivable Network Design Library (SNDlib) : France instance 4 Servers 1 SR 500 HBs with an average of 20 HB/router 1 to 4 clients/HB with an average of 2 clients/HB
11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Simulation environment 1/2 Servers, SR and routers connectivity : 2.5 Gbps Clients connectivity [0.512 , 100] Mb/s HB connectivity : 30 Mbps uplink and 70 Mbps
downlink 500 videos that can be served by all servers with
3 different resolutions 352 x 288, 720 x 576 and 1408 x 1152 With probability 1/5 , 2/5 and 2/5 respectively Each resolution with 3 different bitrates
Video session duration: 250 s client requests are generated in a Poisson model
during 250 s Video popularity fits a zipf-like distribution with a
skew of 0.733 20% of videos are cached in the HB overlay
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Simulation results 1/4
Average server load
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30% and 40% of the server load are
saved with respectively 50%
and 100 % participating HBs
11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Simulation results 2/4
Mean RTP packet loss
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because of considering
congestion at all levels the packet
loss is significantly reduced
11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Simulation results 3/4
Average path delay vs. simulation time
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The more numerous are
the participating HBs, the smaller is the path delay
11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Simulation results 4/4
Mean path distance
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Conclusion & future work Summary
Design of P2P based internet video delivery among controlled HB nodes
Popularity based offline video content injection Two level server selection strategy Performance evaluation
Perspective Improve the caching strategy with an online video
caching and replacement more reactive HBs’ caches maintenance Cost optimization
Achieve real development and evaluation of the extended solution in the framework of the large-scale European project ALICANTE
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11/06/2011 Workshop on Multimedia-aware Networking (WOMAN’11) co-located with ICME 2011
Thank you for your attention!
Question ?