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PPLive : A Measurement Study of P2P IPTV System. Sergio Chacon. Abstract. IPTV stands for Internet Protocol Television P2P IPTV refers to the delivery of TV over IP using point-to-point techniques PPLive is one of the most popular IPTV systems for campus and residential access
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PPLive: A Measurement Study of P2P IPTV System Sergio Chacon
Abstract • IPTV stands for Internet Protocol Television • P2P IPTV refers to the delivery of TV over IP using point-to-point techniques • PPLive is one of the most popular IPTV systems for campus and residential access • Hei, et al., Polytechnic University in Brooklyn, developed a PPLive crawler to carry out in-depth measurements of mesh-pull PPLive
Introduction • Widespread adoption of broadband (residencial) • Application-level, P2P, mesh-pull P2P • Mesh-Pull most successful so far • Rapid deployment @ low cost • Minimal infrastructure • BitTorrent • Not feasible for real time • No fair resource sharing • Not for large-scale live streaming
Answer to questions • What are the user characteristics? • How much overhead and redundant traffic? • What are characteristics of peer partnerships? • What are fundamental requirements for successful mesh pull?
Mesh-Pull P2P Streaming Systems • Streaming peer node • Includes streaming client and server • Channel stream server • Converts media to small video chunks • Tracker server • Provides streaming channel, peer and chunk information for each peer node • Downloads video chunks from multiple peers requesting same media content
Global view of user behavior • Peer tracking methodology • Evolution of participating users • User arrivals and departures • User geographic distribution
Peer tracking • Peer registration • Bootstrap • Peer query
Peer registration • Peer registration • Bootstrap • Peer query
Peer playback delay and lags • Start-up delay • Video buffering • Playback lags among peers
Start-up delay • Time interval between channel selection and playback • P2P also have to deal with startup buffering and delay • 5-10 seconds from selection to player startup • 5-10 seconds from player startup to play
Connection + traffic characteristics • Isolating video traffic • Video traffic redundancy • Download and upload video traffic • Video TCP connections
Properties of video tcp connections • Duration of TCP connections • Number of partners • Dynamic of partners • Locality of partners • Traffic volume breakdowns • Uni-directional or bi-directional traffic?
Uni-directional or bi-directional traffic? • Traffic flows are neither tree-like nor uni-directional (mesh) • Closer in character to BitTorrent • Lesson learned: mesh-pull architectures are more correctly viewed as variations on BitTorrent rather than variations on tree-pull architectures such as end-system multicast
conclusions • Current Internet is capable of providing IPTV @ low cost with minimal dedicated infrastructure • Measurements provide understanding of how to architect large-scale P2P IPTV • Areas of improvement: • Shorter start-up delay • Higher-rate streaming • Smaller peer lags • Better NAT traversal