Research And Implementation Of Video Streaming System Based On BitTorrent

In recently years, Multimedia Streaming such as Live Streaming or Video on Demand becomes the dominant application of Internet. BitTorrent is a popular Peer-to-Peer file sharing protocol, but it lacks in support of video streaming. This paper intends to study what changes should be made to BT to make it support media streaming service as well as file sharing.This paper firstly reviews the P2P content delivery technology, which includes P2P file sharing and P2P media streaming, with focus on the key technologies on P2P media streaming system.Then we give a comprehensive study of BitTorrent protocol. After analyzing the different requirements of file sharing and media streaming, we concentrates on three aspects of BT to make it support VoD service:we modify the piece selection strategy to meet the need of playback deadline of video data; we analyze the inefficiency of choking algorithm and propose choking based on peers'forwarding ranks; we propose an Least Requested Peer algorithm to distribute the requests more evenly among peers.We have designed and developed a VoD System-NexusSwarming, based on our study above. It can run on IPv6 Network and support common video file formats such as wmv, avi, etc. We have conducted several experiments to study the performance of NexusSwarming, and the result shows the system can provide low start-up latency and smooth streaming experience to viewers and it blend in well with the current BT file sharing network, which proves our research results.We also give a preliminary study on how to modify BT to support live streaming.Our research extends the BT protocol to its service for both file sharing and stored media streaming, and provide a better experience for BT users.