不同覆盖网拓扑结构下流媒体传输性能的研究.pdfVIP

∗ 不同覆盖网拓扑结构下流媒体传输性能的研究 高原, 史元春, 肖鑫 (清华大学 计算机科学与技术系,北京市 100084) The Study on Performance of Streaming Media under Different Overlay Topology GAO Yuan, SHI Yuan-Chun XIAO Xin 1(Department of Computer Science and Technology, Tsinghua, Beijing 100084, China) + Corresponding author: Phn: +86-10-6279-7003 ext. 803, E-mail: gaoy03@ Received 2004-00-00; Accepted 2004-00-00 Abstract: With the wide use of streaming media, overlay, which is the base of streaming media transmission, has become a hot research area. While the topology of overlay changes from traditional tree to mesh, there still remains a lack of research on how different topologies under different physical networks will impact on the performance of streaming media transmission. This paper will fill up this gap, and present an overlay topology choosing strategy. We build tree as well as mesh overlay topology based on different network topologies, which are gained from GT-ITM using the Transit-Stub model. We use TORM and PowerP2P as the instances of tree and mesh topology transport protocols respectively. We analyze and compare the simulation results got through NS2, find out the relationship between delay, throughput and the distributing of the nodes, the overlay topology we choose. Based on these results, this paper proposes a strategy on how to choose an overlay topology when the distributing of the nodes is known. It can be a guide when someone wants to deploy a transmission of the streaming media on a network. Key words: streaming media; overlay; tree; mesh; 摘 要: 随着流媒体应用的大量兴起，流媒体传输的基础——覆盖网已成为研究的热点。覆盖网拓扑从传 统的树形拓扑向网状拓扑发展。然而两种拓扑在不同的物理网络下对流媒体传输性能的影响却缺乏系统的 研究。本文在NS2 上对两类传输协议的性能进行仿真测试，得出覆盖网延迟、吞吐量与节点规模、节点分 布情况和所选拓扑之间的关系是，对于延迟，小规模节点下树结构优于网结构，大规模节点下当节点度数 较多时，网结构优于树结构