P2P计算通过大量自治的节点协作共享资源与计算,为空间数据和空间操作的分布提供了新的分布式计算模式。分布在不同Peer上的空间数据库节点通过P2P协作构成一个超级全局空间数据库,全局空间数据目录是P2P环境下快速定位空间数据资源和空间计算节点的关键技术。Peer数据库节点的数据模式、元数据、资源状态参数等抽象为一系列关键词集合。全局目录基于Peer空间数据库节点的外包矩形进行动态聚类并建立P2P环境下的空间索引,支持Peer空间数据库节点的动态加入和退出,支持复杂空间查询和关键词查询。该文给出了全局空间数据目录的组织模型、P2P空间数据索引及空间资源发现算法。
Peer-to-Peer computing provided a new distributed computing pattern for spatial data and spatial operation distribution based on large amount of self- organized peers' collaboration. Spatial databases located on different peers collaborated with each other form a super global spatial database,and global spatial data directory is the key technology to locate spatial resources and spatial computing peer in Peer-to-Peer networks. Parameters such as database schema, metadata and resource status are abstracted as keyword collections. A Peer-to-Peer spatial index was build dynamically based on peers'spatlal data minimum bounding rectangle (MBR) by global spatial data directory,and supported peers' dynamic join and exit. Complex spatial query and keyword query are also well supported by this Peer-to-Peer spatial index.