Bo Li - Hong Kong University of Science and Technology,
Susu Xie - Hong Kong University of Science and Technology,
Yang Qu - Tsinghua University
Gabriel Y. Keung - Hong Kong University of Science and Technology,

The Peer-to-Peer (P2P) based video streaming hasemerged as a promising solution for Internet video distribution.Leveraging the resource available at end users, this approachposes great potential to scale in the Internet. We have nowseen the commercial P2P streaming systems that are orders ofmagnitude larger than the earlier academic systems. We believeunderstanding its basic principles and limitations are importantin the design of future systems.The Coolstreaming, first released in summer 2004, arguablyrepresented the first successful large-scale P2P live streamingsystem. Since then, the system has been significantly modifiedand commercially launched. This paper takes an inside look atthe new Coolstreaming system by exposing its design optionsand rationale behind them, and examines their implications onstreaming performance. Specifically, by leveraging a large set oftraces obtained from recent live event broadcast and extensivesimulations, we study the workload characteristics, system dynamics,and impact from a variety of system parameters. Wedemonstrate that there is a highly skewed resource distributionin such systems and the performance is mostly affected by thesystem dynamics. In addition, we show that there are inherentcorrelations and fundamental trade-off among different systemparameters, which can be further explored to enhance the systemperformance.