基于P2P网格的视频点播自适应性研究

研究了基于P2P网格的网络自适应视频点播的可行性及有效性．在提出的GridVOD系统中，点播用户在享受服务的同时也能够作为mini-server向他人提供服务，系统在利用P2P获得良好的可扩展性的同时，基于网格的安全策略为系统管理提供了保障．GridVOD将具有相似兴趣的关联结点组织在对等结点自治组中，利用基于网格环境的系统监测服务进行网络自适应视频组播，并且利用分布式协同缓存来增强本地服务能力．分析表明，网络自适应视频点播机制提高了系统的服务质量．

Network-Aware Video-on-Demand Policy Based on P2P Grid

Due to the large storage and the powerful processing capability in current client-side devices, user host can serve as both a client and a mini-video server. In order to achieve a secure and efficient organization, the proposed GridVOD system in this paper is based on peer-to-peer grid. Intuitively, the peers who share similar interests tend to have a high probability of connecting to each other. Then an interest-based group model is used to organize the peers with similar interests into an autonomous group. Based on the monitoring service in this GridVOD system, a network-aware video delivery strategy is designed to improve stream quality and enhance system utilization. Because most of the hot video titles are cached in the distributed cooperative cache based on the autonomous groups, a lot of video services can be supplied locally. The simulation results show the efficiency of this proposed network-aware VOD policy.