Study Of Spatial Data Grid Concept System

The grid, new generation of computation infrastructure, emerges in the scientific research and the cooperation, and rapidly develops with the Internet technology. It synthesizes the entire network a giant supercomputer. In the Internet, it connects in a logical way all kinds of resources which distribute in the wide area, including computation resources, software resources, memory resources, data resources, and information resources in order to realize the resources sharing and harmonious cooperation among hypothesized organizations which scatter everywhere in a dynamic changing environment.The mixture of the grid technology and the space information science has produced Spatial Information Grid (SIG) and Grid GIS. As an important constituent of SIG and the Grid GIS, the spatial data grid plays a significant role in the entire spatial information grid.This article focuses on the systematical research and discussion about the basic concept, the strut technology, the structure and the key technology of the spatial data grid, and provides the concept system of the spatial data grid.The introducing data grid technology and constructing the spatial data grid may improve spatial data sharing and the application environment. Compared with the current spatial data sharing, the spatial data grid emphasizes the integration of data sharing. In other words it emphasizes the coordination of the data sharing. Its goal is to establish the hypothesized sole system reflection of the spatial data. In this way the users can transparently visit all sharing data through the gateway website, rather than search the spatial data which one wants in millions of websites.This article discusses the advantages and disadvantages of various patterns of spatial data grid, and puts forward the superior pattern for establishing space data grid, namely mixed network pattern. The C/S pattern is used in the partial grid system, while in the overall grid system, each partial grid system's table of content server carries on the interaction and cooperation through the P2P pattern. The mixed network pattern has the advantage of the C/S pattern which is easy to be controlled and the advantage of the P2P pattern which has separating and coupling characteristic at the same time, which can guarantee the safe control in the inner partial grid, and also can guarantee the extensibility of the overall grid system.