P2P Streaming Part2: Design and evaluation of a p2p live streaming application CoolStreaming

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P2P Streaming-Part-2 Design and evaluation of
a p2p live streaming application (CoolStreaming)

• CS 7270
• Networked Applications Services
• Lecture-13

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CoolStreaming/DONet A Data-Driven Overlay
Network for Peer-to-Peer Live Media Streaming

• Jiangchuan Liu
• with Xinyan Zhang, Bo Li, and T.S.P.Yum
• Infocom 2005

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Some Facts

• DONet Data-driven Overlay Network
• CoolStreaming Cooperative Overlay Streaming
• First release (CoolStreaming v0.9)
• May 2004
• Till March 2005
• Downloads gt100,000
• Average online users 6,000
• Peak-time online users 14,000
• Google entries (CoolStreaming) 5130

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Outline

• Motivation
• Background and related work
• Design of DONet/CoolStreaming
• Implementation and empirical Study
• Future work

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Motivation

• Enable large-scale live broadcasting in the
  Internet environment
• Capacity limitation
• Streaming 500Kbps, server outbound band 100Mbps
• 200 concurrent users only
• Network heterogeneity
• No QoS guarantee

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Client/Server Poor scalability
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IP multicast Limited deployment
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Collaborative Communications
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Outline

• Motivation
• Background and related work
• Design of DONet/CoolStreaming
• Implementation and empirical Study
• Future work

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Related Solutions

• Content distribution networks
• Expensive
• Not quite scalable for a large number of
  audiences
• Self-organized overlay networks
• Application layer multicast
• Peer-to-peer communications

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Related Solutions

• Content distribution networks
• Expensive
• Live streaming (?)
• Self-organized overlay networks
• Application layer multicast
• Peer-to-peer communications

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Application Layer Multicast

• Issue Structure construction
• Tree
• NICE, CoopNet, SpreadIt, ZIGZAG
• Mesh
• Narada and its extension
• Multi-tree
• SplitStream

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Application Layer Multicast (contd)

• Issue Node dynamics
• Structure maintenance
• Passive/proactive repairing algorithms
• Advanced coding
• PALS (layered coding)
• CoopNet (multiple description coding)

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Gossip-based Dissemination

• Gossip
• Iteration
• Sends a new message to a random set of nodes
• Each node does similarly in the next round
• Pros Simple, robust
• Cons Redundancy, delay
• Related
• Peer-to-peer on-demand streaming

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Outline

• Motivation
• Background and related work
• Design of DONet/CoolStreaming
• Implementation and empirical Study
• Future work

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Data-driven Overlay (DONet)

• Target
• Live media broadcasting
• No IP multicast support
• Core operations
• Every node periodically exchanges data
  availability information with a set of partners
• Then retrieves unavailable data from one or more
  partners, or supplies available data to partners

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Features of DONet

• Easy to implement
• no need to construct and maintain a complex
  global structure
• Efficient
• data forwarding is dynamically determined
  according to data availability, not restricted by
  specific directions
• Robust and resilient
• adaptive and quick switching among
  multi-suppliers

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Key Modules

• Membership manager
• mCache partial overlay view
• Update by gossip
• Partnership manager
• Random selection
• Partner refinement
• Transmission Scheduler

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Transmission Scheduling

• Problem From which partner to fetch which data
  segment ?
• Constraints
• Data availability
• Playback deadline
• Heterogeneous partner bandwidth

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Scheduling algorithm

• Variation of Parallel machine scheduling
• NP-hard
• Heuristic
• Message exchanged
• Window-based buffer map (BM) Data availability
• Segment request (piggyback by BM)
• Less suppliers first
• Multi-supplier Highest bandwidth within deadline
  first
• Simpler algorithm in current implementation
• Network coding ?

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Outline

• Motivation
• Background and related work
• Design of DONet/CoolStreaming
• Implementation and empirical Study
• Future work

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PlanetLab Experiments

• Distributed experimental system
• DONet Module
• Console and automation
• Command dispatching and report collection
• Caveats
• Scalability
• Reproducibility
• Representability

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Geographical Node Distribution
May 24, 2004
of Active Node 200-300
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Planet-Lab Result

• Data continuity, 200 nodes, 500 kbps streaming

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Control overhead
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Implementation CoolStreaming

• First release May 30, 2004
• Source code 2000-line Python
• Programming time
• PlanetLab prototype 2 weeks
• Export from prototype 2 weeks
• Support formats
• Real Video/Windows Media
• Platform/media independent
• Scale and capacity
• Total downloads
• Peak time 14000 concurrent users
• Streaming rate 450-700kbps

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User Distribution (June 2004)

• Heterogeneous network environment
• LAN, DSL, CABLE...

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Online Statistics (Jun 21, 2004)
Average Packet Loss around 1 - 5
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Observations

• Current Internet has enough available band to
  support TV-quality streaming (gt450Kbps)
• Bottleneck server, end-to-end bandwidth
• Larger data-driven overlay
• ? better streaming quality
• Capacity amplification

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Outline

• Motivation
• Background and related work
• Design of DONet/CoolStreaming
• Implementation and empirical Study
• Future work

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Future of DONet/Coolstreaming

• Content
• Solution DONet/Coolstreaming as a capacity
  amplifier between content provider and clients
• Virtually part of network infrastructure
• Enhancement
• Scheduling algorithm
• Simplified version
• Network coding
• Transport protocol
• TCP (?)

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Future of DONet/Coolstreaming

• Enhancement (contd)
• User interface
• Combined with caching
• Combined with CDN
• Provide world-wide reliable media streaming
  service
• On-demand streaming

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Q A

• Thanks