VoD集群副本结合代理策略的设计与分析  

Design and Analysis of a Hybrid Strategy in VOD Clusters

作　　者：李旸[1] 吴新亚[1] 

机构地区：[1]上海立信会计学院网络信息中心,上海210620

出　　处：《计算机工程与科学》2010年第3期130-132,共3页Computer Engineering & Science

摘　　要：副本和代理策略是目前在VoD服务中应用最广泛的两种主流技术方案,都是保证终端用户VoD服务实时流畅的有效手段,但以往的研究都局限于研究单一策略对系统性能的提升。本文提出了一种VoD集群文件副本加代理的复合策略,集群中的服务器作为文件副本服务器存在,而同时又具有内容代理服务器的功能,并建立了相应的数学模型。仿真实验表明,相比单一的策略,副本结合代理的复合策略可以减少30%以上的点播延时,满足系统的负载均衡需求,较大程度地减少重定向引起的延时,提高系统的准入概率。Caching and replication have emerged as two primary techniques for reducing the delay experienced by end-users when demanding the VoD services. Previous research tends to focus on either one of them separately. The hybrid strategy uses a VoD server both as a replicator and as a proxy server. An analysis model is proposed to predict the benefit of the strategy. The simulation results indicate that saving up to 30% latency is observed ,under various system parameters,compared to stand-alone replication or caching mechanisms. The hybrid scheme can guarantee the load balancing and thus can provide better QoS guarantee.

关 键 词：视频点播 集群 负载均衡 代理服务器 副本策略 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]