关键词: P2P, 贝叶斯网络, 查找, 路由

Abstract: One of essential problems on P2P network is how to find a node which saves expected data.So exploring lookup algorithms is a key component for P2P technology，which decides the performance of P2P system.Each node keeps a list that records the routing information of its neighbor.This paper focuses on building a Bayesian network corresponding with their routing table of nodes.Depending on this Bayesian network，we analyze the node probability of receiving a lookup request and obtain a formula to compute this probability.For making this formula more closed to reality，we assign a weight to each of nodes and adjust these weights.At last，a scheme of assigning reliability to each node is presented and an improved routing algorithm is given based on Bayesian method.Some simulations show that this improved routing algorithm can enhance the performance of P2P network to some extent.

Key words: Pere to Pere（P2P）, Bayesian network, lookup, routing