Research On The Routing Mechanism Of P2P Indexing Networks Of Spatial Vector Data

With the increase of the number of users and transmission amount of data of geographic information system, spatial information on-line services system faces many challenges: networks transmission of massive spatial data extends the system response time; the concurrent requests of a large number of users result in the poor performance of servers. The current study has been restricted to the server-side, which is difficult to solve the problem of system performance fundamentally. The emergence of P2P network provides a new way to solve these problems above. P2P network can connect all kinds of computers equally, Take full advantage of the computing and service capabilities of the client, improve the performance of geographic information system apparently. However, the existing P2PGIS systems still face with the problem of low routing and query efficiency.In this thesis, based on the Hybrid P2P Spatial Indexing Network, the query algorithms of spatial vector data and routing mechanisms of P2P network are studied. On the vector data query algorithms, a vector data query algorithm based on the Hilbert space filling curve is designed. The simulation result shows that the algorithm can reduce routing hops and shorten response delay on the vector data query. On the routing mechanisms of P2P network, the efficient routing protocol—chord is introduced in the framework of JXTA by expanding and modifying JXTA routing protocol scheme, integrating distributed hash table (DHT) technology. In addition, a P2P prototype system based on JXTA platform of vector geographical data on-line services is implemented by JAVA, which can process the multi-layer and multi-scale dissemination and query of vector data. The test result shows that the system can offer a good vector data on-line services and higher query efficiency.