中文摘要：

为了更好地利用服务器提升P2P网络的性能，提出了一种P2P网络服务器最优化部署方案．该方案将如何部署有限的服务器资源来满足尽量多节点的问题，转化为一个带有约束条件的最优化问题．考虑到极坐标空间适合于表达长度相关的约束条件，例如部署方案中的约束条件，提出一种基于极坐标映射的启发式算法，解决P2P网络服务器最优部署问题．相比于通常的使用罚函数的启发式算法，该算法可以有效地减小搜索空间，其性能的改善在搜索空间维数高的情况下更加显著．实验结果表明，所提出的服务器部署方案可以满足更多节点的需求，能够有效提高P2P网络的性能．

英文摘要：

An optimal allocation approach of servers for improving the performance of P2P networks is proposed in this paper. The approach is to allocate a limited number of servers over the P2P networks to satisfy as many peers as possible, by using a constrained optimization algorithm. In considering that the polar space is more suitable to express length-related constraints, such as those in this approach, a heuristic algorithm based on the polar coordinator mapping is proposed to deal with the optimization problem of the server allocation. Compared with the existing heuristic algorithms that are based on penalty functions, this algorithm can effectively reduce the search space, and the performance is better especially in a high dimensional search space. The experiment results show that our server allocation approach can satisfy more peers＇ requirement and effectively improve the performance of P2P networks.