嵌入式P2P VOD系统上面向内容的动态缓存策略

Dynamic Buffer Mechanism of P2P VOD on Embedded System

随着P2P技术的发展和IPTV的逐步推广,两者的结合应用越来越广泛。P2P流媒体的实质是基于分享的精神,充分利用每个客户的上传带宽,以减少流媒体服务器端的负载。关于VOD点播中的P2P技术,现有的大部分研究都集中在节点的选择策略、P2P网络的拓扑结构以及各个客户端的上传带宽和上传质量等。这些研究显著地改善了P2P点播系统的性能。采用基于嵌入式系统的面向内容的P2P点播缓冲机制,可以最大限度地减少嵌入式系统弱点(存储容量非常有限)的影响,并基于内容热度做出智能的缓冲机制。使用这种新的机制,嵌入式P2PVOD系统可以得到一个较小的网络组建时间和更高的数据共享率。

P2P network is widely used in IPTV systems now. The essence of P2P streaming is making use of the upload bandwidth of each peer to reduce the load of the streaming servers. Regard to VOD P2P network, most of the existing researches are focused on peer selection strategies, such as the peer topology, peer bandwidth contribution, balance of peer churn and stream quality. These researches do make a significant improvement to the P2P live streaming and the P2P VOD systems. In this paper, we designed a new content-oriented buffering mechanism for P2P VOD on embedded system. It can minimize the weakness of embedded system （few memory and storage）, and make an intelligent buffer mechanism at the basis of content popularity. Using this new mechanism, P2P VOD system can get a lower built-up time and a higher data sharing rate.