在BitTorrent(BT)系统中,种子节点提供绝大部分的文件块上传服务,尤其是初始种子节点在整个文件上传和下载中起着很重要的作用。研究目前出现的几种基于种子的文件块分发策略,提出一种基于CBT系统的种子覆盖网,在减少种子平均上传花费和平衡种子负载的基础上,通过提高整个系统的文件块分发效率和整合CBT技术,来提高系统的性能。仿真实验结果表明,节点的下载速度和系统性能有明显地提高。 In the BitTorrent (BT) system, the seed node provides most of the file block upload service, especially the initial seed node plays an important role in the entire file upload and download. This paper studies several seed-based file block distribution strategies and proposes a seed coverage network based on CBT system. On the basis of reducing the average seed upload cost and balancing the seed load, by improving the efficiency and integration of the whole system file block distribution, CBT technology to improve system performance. The simulation results show that the node’s download speed and system performance are obviously improved.