一种可扩展的P2P流媒体点播服务体系  

Design and Evaluation of a Scalable P2P Video-on-Demand System

作　　者：彭昭[1] 杨宗凯[1] 陈京文[1] 朱自珍[1] 

机构地区：[1]华中科技大学电信系,湖北武汉430074

出　　处：《小型微型计算机系统》2009年第9期1730-1733,共4页Journal of Chinese Computer Systems

基　　金：国家自然科学基金项目(60773193)资助;国家发改委CNGI示范工程项目(下一代互联网示范工程2006年产业化及应用实验)资助

摘　　要：大规模对等网络点播服务的主要挑战在于有效的资源调度和难以预测的用户行为.本文借鉴BitTorrent(BT)算法原理,提出基于异步传输的可扩展对等网络点播系统.该系统采用集中式节点定位以及非结构化拓扑,通过异步传输机制提升媒体数据资源共享度,引入基于优先级和稀有度的数据传输调度提高播放连续度,提出一种低复杂度的缓存维护策略减少系统维护开销,并定义"发送方"激励机制确保节点持续共享带宽和数据资源.数据包级仿真实验分析表明,本系统在播放连续度、启动时延以及服务器压力等方面均能较好地满足大规模网络点播应用的要求.Large-scale Peer-to-Peer （P2P） Video-on-demand （VoD） service provisioning remains challenging due to effective resource scheduling and unpredictable actions of users. Inspired by the success of BitTorrent （BT） in the field of file sharing, a scalable P2P VoD system based on centralized directory service and unstructured overlay is presented in this paper. The system is specified with asynchronous data transfer mode to improve the degree of resource sharing among peers, a data transfer scheduling algorithm based on the priority and rareness of data blocks to smooth video playback, a novel cache maintenance strategy to reduce the load of centralized directory server, and a supplier-based incentive to encourage the resource sharing among peers. Packet-level simulations show good performance of the presented system in terms of playback continuity, launch delay and server stress, which can meet the requirements of large-scale VoD service.

关 键 词：对等网络 异步传输 点播 激励机制 

分 类 号：TP393[自动化与计算机技术—计算机应用技术]