P2P流媒体内容分发关键技术研究

【作者】 谭遥骋；

【导师】 张修如；

【作者基本信息】 中南大学 ， 计算机软件与理论， 2008， 硕士

【摘要】 Internet技术的飞速发展,虽然使流媒体分发技术取得了长足的进步,但日益增加的用户和视频数据也给大规模流媒体分发服务带来了新的挑战。与此同时,P2P技术也随着网络带宽的改善和用户端计算机性能的增强而迅速兴起,如何充分利用原先被忽视的宝贵的用户端资源,在动态的P2P网络环境中构建大规模、高可扩展、高可靠、高播放体验的P2P流媒体分发系统成了近年来研究的热点之一。论文对基于P2P网络的媒体数据分配方法和节点间的合作机制两方面进行了研究,设计出了一个基于域的流媒体数据分配算法MSDD,和一种基于流证书的节点间合作机制CMNSC。MSDD算法考虑到了当今网络的实际状况,对供应节点的带宽不作限制,并且允许一个供应节点同时为多个接收节点提供服务,此外该算法把节点在网络中的物理位置作为一个重要的系统参数,使各节点优先在本域内请求或提供服务。算法在确定供应节点集时采用试分配的策略,选出传输延迟最小的供应节点集作为正式供应节点集,次之的作为备用供应节点集,以此类推为接收节点提供动态数据传输服务;CMNSC机制采取系统通过检查、统计流会话结束后由接收节点颁发给发送节点的流证书,及评判节点在线行为的方法来为各节点打分,并设定节点被评分值的高低与其在系统中享受的优先权、服务质量成正比的策略来激励各节点尽可能的共享其拥有的资源。仿真实验结果显示MSDD算法和CMNSC节点间合作机制能给P2P流媒体内容分发性能带来改进。更多还原

【Abstract】 With the rapid development of the Internet, the media streaming technology has achieved great progress, but the increasing consumers and videos bring a new challenge to the media streaming distribution technology in a large scale. At the same time profit from network bandwidth and the capacity of user end-systems continue improving, peer-to-peer (P2P) technology quickly spring up. So how to utilize the valued end-systems resources to build a P2P media delivery system with large-scale, high scalability, reliability and performance in a dynamic P2P network environment becomes a hot research topic in recent years.The dissertation focuses on researching the media data distribution method and the node cooperation mechanism which based on P2P network, for the two issues a method Media Streaming Distribution based on Domain (MSDD), and a Cooperation Mechanism between Nodes based on Streaming Certificate (CMNSC) have been presented. MSDD takes the conditions of nowdays network into account not restrict provide node’s bandwidth and allows one provide node services many request node at one time, furthermore takes node physical address as an important system parameter to make every node first request or provide service in its domain. MSDD adopts test distribution method to select the set of provide node, namely the set has the least transmission delay is first been selected, has the second little transmission delay is the standby, and by parity of reasoning to transmit datum in dynamic mode. CMNSC adopt the strategy to stimulate every node share their resources, that is node issues certificate, system grades all nodes mainly by checking and counting certificate and judging the behavior of node on line, the higher score a node is, the more priority and better service a node can get.The simulation results demonstrate the performance of media streaming content distribution based on P2P network has been improved by adopts MSDD and CMNSC.更多还原