关键词: Bittorrent, Traceroute, Peer选择算法

Abstract: In the traditional Bittorrent protocol，the tracker adopts the random peer selection algorithm to construct the peer list.It doesn’t consider the distance and connection performance among the peers.In this paper，a sort of peer selection algorithm based on traceroute（PSBT） is proposed.The results of the traceroute is used to do the topology discovery and through that the peers which are near to the requester to construct the peer list is chosen.As the simulation showing，PSBT algorithm not only enhances the performance of file downloading but also reduces the traffic of the core domains effectively.

Key words: Bittorrent, Traceroute, Peer selection algorithm