中文摘要：

视频点播目前已成为对等（peer-to-peer，简称P2P）络中一项重要的应用，引起了人们的不少研究兴趣．由于P2P网络能够为VoD（video-on-demand）应用的大规模实现提供底层网络的支持，许多正在出现的P2P VoD分发策略都能够提供在P2P网络中最基本的数据传输方式对以往主要的P2P VoD内容分发策略进行了总结和概括．首先介绍了设计P2P VoD策略的相关重要问题，并把策略根据内容分发方式的不同分成4种类型．最后讨论了它们的应用层性能，并提出未来可以延续的工作．

英文摘要：

Video-on-Demand, which is an important application in peer-to-peer （P2P） networks, has attracted a lot of research interests recently. As P2P network is easy to deploy and can provide a large-scale substrate networks, many P2P VoD content distribution schemes have emerged to offer the basic function of data transportation. This paper presents a survey on the state-of-the-art P2P VoD content distribution schemes. It first summarizes the key issues in designing P2P VoD schemes and then categorizes these schemes into four groups according to data transportation method. Finally, it discusses the application-level performance and outlines possible future work.