中文摘要：

流媒体应用有着实时性、连续性、带宽消耗大等特点,对传输网络提出了较高的要求.用户接入网作为传输网络的重要组成部分,对流媒体服务质量有重要影响.新一代高性能宽带信息网的试运行,初步验证了大规模汇聚接入网络技术在某些条件下支持流媒体的有效性.然而,由于某些限制,在试运行中还不能实现在大规模用户并发访问流媒体服务器的条件下的验证,而在仿真中却可以实现这种验证.在本文中,我们对于面向不同接入网的分布式VoD系统作了仿真比较.结果表明,面向大规模汇聚接入网的VoD系统在接入路由器无拥塞时,在相同的硬件成本下,在端到端时延及其抖动指标上有较大的提高.

英文摘要：

Streaming media services have characteristics of real-time,continuity and large bandwidth consumption. These put a higher requirement on networks. An access network is an important part of intemet and has significant effects on the service quality of streaming media. The test run on the China＇ s High Performance Broadband Information Network has validated that the largescale converging access network can effectively support streaming media under some situations.However, due to some resections, the test mn can not validated the efficiency under the situations when large-scale users simultaneously access media servers. But the validations can he achieved in simulation. In this paper, we compare distributed VoD systems on different access networks by simulation. The results show that when the access router has no congestions, the VoD system on the converging access network has better performance in terms of end-to-end delay and jitter at the same hardware cost.