摘要： 分析当前最流行的P2P软件——BT的工作方式，发现其内容分发算法使得文件片段在网络节点中分布不均，影响系统效率。提出基于种子控制的内容分发算法，该算法能有效避免稀有片段的产生，使各节点上的片段拥有量基本相等。采用单次分发时间、节点上内容相异性和平均下载时间等几个方面对新旧系统进行评估比较。仿真试验结果表明，加入新算法的系统降低了平均下载时间，提高系统的健壮性和整体效率。

关键词: BT算法, 文件共享, 内容分发

Abstract: This paper analyzes the most popular Peer-to-Peer(P2P) software currently, BitTorent(BT) working methods, and finds that the content distribution algorithm makes document fragments distribute uneven among the network nodes, which impacts on the efficiency of the system. It proposes an algorithm to control the content distribution of the seeds. This algorithm can effectively avoid the document fragments to be distributed uneven in the network, so that all nodes have the similar number of fragments. This paper compares the new system with the old system from the aspects of distributed time, content diversity of the nodes and average download time of all the nodes. Simulation results show that the new system reduces the average download time and improves the robustness and efficiency of the whole system.

Key words: BitTorent(BT) algorithm, file sharing, content distribution

中图分类号: 

• TP393