BitTorrent类型P2P系统模型研究与性能分析

对BitTorrent（BT）类型的P2P系统进行了建模与性能分析。详细地分析了系统中的peer行为。考虑到文件片段对系统的影响，建立了peer模型和seed模型以及文件片段模型、感兴趣与阻塞模型、peer选择模型等。对peer在BT子系统中对邻居peer的感兴趣概率、被邻居peer阻塞的概率以及选择上传peer的概率进行了分析。应用这个模型对peer的上传行为发生的概率与BT子系统peer总数的关系进行了分析, 结果表明, 上传行为发生的概率随着BT子系统peer总数的增加而减少。

Model Research and Performance Analysis of BitTorrent-Like P2P System

A model and performance analysis of BitTorrent(BT)-like P2P system was presented. The peer behavior in this system was analyzed in detail. A peer model, seed model, file fragment model, interesting and choking model and peer selection model were built while considering the effects of file fragment on this system. The probability of a peer interested in neighbor peer at BT sub-system, the probability of a peer being choked by neighbor peer, and the probability of uploading peer being selected were analyzed. By this model, the relation between the generant probability of a peer uploading behavior and the whole peer number at BT sub-system was studied. The data result showed that the generant probability of a peer uploading behavior decreased as the whole peer number at BT sub-system increased.