Abstract: Unnecessary network stream could be brought by the problem of topology mismatching in P2P（Peer-to-Peer） networks.So both the overhead of the physical network and the average time delay for information searching between peers are aggravated.In this paper，a P2P network model CSL（center-super-leaf） based on physical topology is presented.There are three layers in CSL model.They are center layer based upon the physical links among autonomic systems，super layer based upon the network addresses of peers，and leaf layer built by common nodes.Meanwhile corresponding algorithm to run the network is given.The experiments show that in CSL model，the average time delay for information searching between peers could be obviously decreased.The CSL-P2P network what is presented to solve mismatching problem could work well.Especially when there are large-scale peers in P2P network，it could performance better in decreasing both the overhead of the physical network and the average time delay for information searching between peers.

Key words: Peer-to-Peer（P2P）, topology mismatching, Center-Super-Leaf model（CSL）, information searching, average time delay

摘要： 对等网络的拓扑失配会引起不必要的网络流量，不仅加重了物理网络的负担，而且加大了节点间资源搜索的平均时延。提出一种基于物理拓扑信息的P2P网络模型CSL。CSL模型是以自治系统之间的物理连接构成Center层，以节点的网络地址构成Super层，由普通节点形成Leaf层的三层模型，并采用相应的算法维护网络的运行。通过实验表明，CSL模型在资源搜索时可以明显降低系统的平均时延。针对拓扑失配问题提出的CSL模型可以很好的工作，特别是节点规模较大时在减轻网络负担和降低资源搜索的平均时延方面表现更好。

关键词: 对等网络, 拓扑失配, CSL模型, 资源搜索, 平均时延