Performance Analysis of BitTorrent-Like P2P Networks for Video Streaming Services at the Chunk Level

Peer-to-Peer (P2P) networks are distributed systems where no central authority rules the behavior of the individual peers. These systems rely on the voluntary participation of the peers to help each other and reduce congestion at the data servers. BitTorrent is a popular file-sharing P2P application originally designed for non real-time data. Given the inherent characteristics of these systems, they have been considered to alleviate part of the traffic in conventional networks, particularly for streaming stored playback Video-on-Demand services. In this work, two strategies for implementing a streaming service for stored playback video are presented and studied through simulations at the chunk level. First, a window-based peer selection strategy for P2P networks is proposed that greatly improves the chunk sharing process for such video services. The basic idea is to select the downloader peers according to their progress in the download process. Second, a priority scheme is proposed and analyzed that benefits the peers that are more likely to remain longer in the system by serving them first. The simulation model offers complementary results to the conventional fluid or Markovian models.