VoD系统中磁盘存放策略的研究

1.引言过去十年里,网络和多媒体技术的飞速发展,使VoD成为可能。VoD是一个一般的实例,它由客户发起接收远地存储的视频,要求在可接受的短时间内收到(有一定的实时要求),并在客户端回放,同时服务方提供的视频量具有相当大的规模。它改变了传统的用户被动接受的方式(如收看电视),而代之以交互的方式,变革了人们传统的娱乐方式,具有极为广阔的前景。因此,引起人们广泛而深入的研究。 VoD系统设计中,最终是为了提供尽可能多的并发数据

Data Placement Policy in Distributed VoD Systems

One of the significant tasks when designing a VoD(Video-on-Demand) system is to support as many simul-taneous streams as possible. Obviously, it is closely related to the storage subsystem. In this paper, we compare theperformance of the storage subsystems based on two different designs by simulation, one data placement policy is us-ing the technique of striping, and the other is simply placing a whole video only in one server. We find that, when da-ta is CBR (Constant-Bit-Rate) coded, the numbers of simultaneous streams respectively supported by the twoschemes are equal, but the latter can present better service.