一种面向文件片段选择策略的对等网络污染方法

为了提高对等网络(P2P)文件共享过程的控制效果,提出了一种面向P2P文件共享系统中文件片段选择策略的P2P污染方法,并通过数学建模对污染效果进行了分析.该方法利用P2P文件共享系统中最少优先的文件片段选择策略,通过干扰文件片段的副本数达到控制文件传播的目的.实验结果表明,污染是否成功由初始资源提供节点退出P2P文件共享系统的概率和系统内污染节点的数量相互作用来决定,退出率和污染节点数量越高,文件片段污染越容易成功.当污染失效时,节点完成整个文件下载所用时间近似服从Frechet分布.当污染成功时,该方法可以在污染者不发送文件数据的情况下,使整个文件共享系统中每个资源请求节点都无法完成文件下载,因此具有污染效果好、对网络与计算资源要求低的优点.

Pollution for Selection Strategy of File Segment in Peer-to-Peer System with Modeling and Analyzing

To promote the effect of peer-to-peer(P2P) file sharing control,a pollution method pointing to the selection strategy of file segment in P2P file-sharing system is proposed,and the mathematical model is established to analyze the pollution effect.The rarest first policy of file segment selection in P2P system is used to pollute the quantity of the file segment copies.The simulation demonstrates that the success of pollution depends on the mutual action of the exit rate of the initial data provider and the quantity of the polluter.The higher the exit rate of the initial data provider and the quantity of the polluter are,the higher the success rate of pollution is.If the pollution fails,the downloading time of the file is close to Frechet distribution.While the pollution succeed,without sending any data of a file,the polluter makes every downloading node in the P2P system fail to accomplish the file downloading.The proposed pollution method is effective requiring less computing resources.