The Minimum Buffer Size Estimate In Max Strategy

With the development of communication and network technology, It is a system bottlenecks that the traditional C/S mode and unicast way to push media stream of streaming media services system as the server performance and network bandwidth limits.P2P is a better way in the limited bandwidth to realize high quality audio video file transmissionP2P is short for Peer to Peer. It means Peer-to-Peer computing or a Peer-to-Peer network. The core idea is that the use P2P technology applied in real-time streaming data distribution, transfer the network layer multicast function to application layer to realize fully effective use of each node resources. P2P streaming media applications in bases on P2P file exchange. According to the previous technology, users in the Internet to watch the video streaming media download a paragraph from the server and then to play it, Users can only download resources from the server. And the application of P2P streaming media, make it easy to Watch the video streaming media with resource utilization between the user watch video at the same time The user can download the video from these users at the same timeMost existing P2P live stream systems employ Chunk-based design.One video stream is divided into many video Chunks or pieces. The P2P system consists of using the often idle capacity of clients to share the video distribution with servers. The nodes in the network, called Peers, share their Chunks to other nodes, if they all share common interests. Large Chunks leads to long playback delay but reduce package overhead and scheduling complexity. Large buffer size can increase playback continuity but leads to long playback delay. Another important factor is Chunk-selection strategy. An efficient Chunk-selection strategy are indispensable in order to obtain high continuity and low playback delay in a P2P system. "Rarest First strategy" is widely adopted in P2P file distribution protocol and P2P stream protocol. "Greedy strategy" is also very important. Combining above two strategies, we get "Mixed strategy". Surveys about P2P system for live video distribution.The the continuity is affected not only by Chunk-selection strategy but also the number of Peers and buffer lengthWe develop the simple model for P2P live stream, considering the bandwidth limited f and the number of Chunk that server sends. Then we analysis the performance of continuity with "Mixed strategy" in the new model and the mathematical expression of the minimum buffer size estimate on fixed continuity are also given. Finally we show some illustrative simulation results.