On the Efficiency of Peer-to-Peer File Sharing

In peer-to-peer (P2P) file sharing networks, the average download time is determined by how efficiently the upload bandwidth of each peer can be utilized. In this paper, we will first propose a stochastic model for P2P file sharing networks. By numerically solving the proposed model, we will be able to gain interesting insight on how the performance of a P2P file sharing network is affected by different parameters such as the piece numbers of the file, the number of neighbors of a peer, and the seed departure rate etc. We will also provide some useful guidelines on how to design an efficient P2P system based on our results.