Abstract: This paper establishes an optimal downloading model for heterogeneous wireless mesh networks，and based on the model, the optimal algorithm is proposed in terms of the performance to minimize downloading time and costs of downloading nodes. This paper presents a variable topology different from the traditional tree-graph mixture of overlay network, in order to improve the algorithm’s adaptability and scalability. On this basis, the fastest downloading algorithm is proposed based on minimum cost network flow theory. The algorithm includes the selection strategy of optimal peer nodes and the file’s partition strategy. Simulation results justify the validity of the algorithm. Compared with other algorithms, the algorithm can obtain a minimum downloading time, and at the same time, the node’s downloading cost tends to the optimal solution.

Key words: wireless Mesh network, topological structure, minimum cost maximum flow, optimal peer selection, partition strategy

摘要： 建立了异构无线Mesh网络的最优下载模型，基于这一模型，从下载时间和下载费用最小化的角度出发，提出了最优下载算法。构架了不同于传统树形图状混合的覆盖网拓扑结构，提高了算法的适应性和可扩展性。在此基础上，提出了基于网络流理论的最小代价最快下载算法，包括最优源节点选择和文件分块策略。仿真结果验证了算法的有效性，与其他算法相比，该算法能在下载时间最小的同时令节点的下载费用趋于最优解。

关键词: 无线Mesh网络, 拓扑结构, 最小费用最大流, 最优peer选择, 分块策略