The Architecture of a Dynamic Distributed Gis

Current GIS development pays more attention to the ability of distribution based on the client-server architecture. In a batch mode distributed GIS, a file server functions passively. Information sharing and integrating are far from concurrent, nor is the database integrity controlled. The dynamic Voronoi data model, equipped with a dedicated spatial server, presents a bright future in overcoming these shortcomings. In a dynamic distributed GIS, the spatial database is maintained in the server machine which provides database services to clients through different views. A view is an image of a partial map. Any access to the database through views must be examined and performed by the spatial server. Should the database is modified by an authorized user, the change could be reflected simultaneously on all relevant views. Spatial searches through the database could be achieved efficiently without additional indexing. As the spatial database gets bigger and more complex, some compact objects based on spatial proximity could be constructed, which brings a hierarchical representation of the Voronoi diagram. The architecture of the dynamic distributed GIS also provides feasible solutions towards large spatial problems with divideand-conquer and parallel processing approaches.