基于社交网络的P2P内容分发算法研究

Exploiting Online Social Networks to Accelerate Peer-Assisted Content Distribution

随着互联网社交网络应用的流行,基于社交网络的P2P应用也渐渐涌现。社交网络的最大特点是网络中的节点是建立在真实的社交关系之上。BitTorrent作为P2P文件共享的典型应用,为了限制和惩罚系统中节点的"搭便车"行为,引入了一种Tit-for-Tat的阻塞机制,该机制有效地限制了系统中节点的"搭便车"行为。但与此同时,TFT阻塞机制也限制系统整体性能的提高。提出了一种基于社交网络的自适应阻塞算法来解决上述问题,并利用仿真实验证实改进后的算法比传统的基于TFT的阻塞算法能有效地降低系统的平均启动延迟时间和下载完成时间。

With the popularity of online social networks （OSN）, the P2P application built on the social network is emerging in recent years. The unique feature of online social networks is that nodes in the online social network are associated with people in the real world. BitTorrent, as a typical P2P content delivery application, introduces a ＂Tit-for-Tat＂ （TFT） mechanism to limit free riding. TFT mechanism can effectively prevent nodes from acting as a ＂free rider＂. But at the same time, it also limits the distribution efficiency of the whole system. In order to solve the problem that TFT mechanism hindered nodes from more efficient cooperation, an adaptive chocking algorithm was proposed based on the online social network, and the simulation experiments confirmed that the proposed algorithm can effectively reduce the average startup time delay and download completion time compared with the traditional TFT-based algorithm.