基于平衡兴趣树的P2P空间数据服务调度*

构建空间信息网格要求解决海量地理空间数据传输问题，通过分析空间数据服务特征，对空间数据设计了多级网格索引，利用P2P技术设计了基于平衡兴趣树的空间数据服务网络模型。算法按peer兴趣区对申请空间数据服务的peer进行组织，将peer间路由关系动态组织成一种新的拓扑结构——平衡兴趣树。算法可动态维护网格热度表中数据块的热度，通过热度表可快速发现网格数据块在P2P网络中的位置并下载，从而减轻了空间数据服务器压力，提高了服务效率。

Spatial data service scheduling algorithm of P2P networks based on balance interest tree

The transport problem of vast spatial data through Internet must be solved in establishing spatial information grid (SIG). Designed the multilevel grid index of spatial data and a network model of spatial data service based on balance interest tree by analyzing the basic character of spatial data service and using P2P technology. According to the interesting region of peers, effectively organized the peers requested spatial data service by the algorithm, and transformed the routing relationship of peers to a new topology structure: dynamic balance interest tree. This algorithm can maintain the degree of heat of data grid in the heat table, and can find the location of data grid in the P2P network quickly by the heat table and download, so the pressure of spatial data service and improves the efficiency of service.