Nowadays, extensive and profound technological changes are taking place in the information field, and new concepts and technologies are being perfected and developed, such as the development of geo-information science, the proposal of the concept of digital earth, the integration of GIS technology and database technology, and the development of information superhighway and Internet. With the rapid development and wide application of Internet and information superhighway, distributed application research and people's growing demand for information and knowledge will inevitably lead to the development of network GIS. Now, the proposal and development of the third generation network technology-grid technology has brought a long-term impact on the development of GIS. In particular, the strategy of "Digital Earth" put forward by former US Vice President Al Gore in June 5438+0998+1October 3 1 needs to process a large amount of geographic information in parallel. At this time, the deficiency of WebGIS appears, because it mainly forms hypertext through hyperlinks, including the realization of parallel computing function, which is fatal to the rapid computing and information sharing required by digital earth and digital city. With the development of grid computing, GIS will develop towards networking, standardization and popularization. GridGIS will also become the core platform of "Digital Earth".

The concept of "digital earth" is actually a form of grid technology in the field of geographic information science. In the network environment, all location-related information is described in digital form and stored as a rich resource. Through information sharing technology, the "on-demand" service is realized, and this spatial information infrastructure becomes a spatial information grid (SIG).

Spatial information grid is the basic development framework for spatial information acquisition and interoperability. Spatial information grid provides an integrated basic technical framework for the acquisition, processing and application of spatial information, as well as an intelligent spatial information processing platform and basic application environment. The foundation of establishing a distributed intelligent spatial computing environment is to establish a spatial grid computing environment based on distributed database management, that is, to support spatial information processing and cross-platform computing in local and wide area networks, to support multi-user data synchronization processing, to support RPC of spatial data, to achieve interoperability of heterogeneous systems, and to support multi-level distributed collaborative work in network environments.

Spatial information grid provides users with an integrated intelligent spatial information platform by using the existing network infrastructure, protocol specifications, Web and database technologies. Its goal is to create a new generation of information platform and software infrastructure based on Interent, built on OS and Web services. On this platform, information processing is distributed, collaborative and intelligent, and users can access all information through a single portal. The ultimate goal of information grid is to realize on-demand service and one-stop service.

In the field of GIS, based on the concept of grid computing, researchers put forward spatial information grid and GridGIS based on service grid. The International Organization for Standardization actively promotes the formulation of relevant standards for grid GIS. Some protocols and standards have been supported by commercial GIS software companies such as ESRI and M apInfo, and achieved results. Internet standards and protocols such as XML are adopted in GIS field, which can combine loosely combined GIS network and geographic information processing service to form spatial information service. ESRI actively supports the development of distributed GIS and GIS service concepts, and Gnet strategy will involve many aspects. The largest level is the World Wide Web, and the smallest level is the Enterprise World Wide Web. Through the support of grid protocol, multiple departments will be able to provide a variety of integrated services and enjoy these services at the same time. It can support enterprise development, provide development components for building GISWeb services in different distributed system environments, and satisfy the establishment of GridGIS. However, the development technologies advocated by different commercial companies are different, showing a continuous development trend.

GridGIS is the technical system of spatial information computing environment and spatial information service, and it is the technical support system to realize spatial information grid, which realizes spatial information sharing through spatial information standardization. Through the standardization of spatial analysis semantics, the interoperability of GIS functions is realized: with the support of grid technology system, GIS functions can be enjoyed in heterogeneous environments.

GridGIS should make use of the existing open GIS GML standard, Web map service standard and grid-related technical standards to provide users with an open technical system of spatial information computing environment and realize the distributed and cross-platform spatial information computing integration of users. The research of spatial information computing environment can be divided into two levels: spatial information depth calculation and spatial information activity calculation. Firstly, the spatial depth calculation system is established through the spatial action law under the fusion of temporal and spatial attributes, so as to obtain the spatial data distribution and simulation; Secondly, on this basis, the spatial intelligent computing strategy with spatial agent as the core is proposed to realize the spatial active computing system.

At present, China has taken grid GIS as the key direction in the information field, conducted in-depth research, and promoted and widely applied the results, forming a series of achievements such as grid GIS architecture, standards and specifications, key technologies, software platforms and application demonstrations, which have been applied in many fields.

On June 5438+ 10, 2008, combined with the cutting-edge research results of grid computing technology at home and abroad, the Ministry of Science and Technology established the "863" project "Grid Geographic Information System Software and Major Applications", formulated the interoperability technology of heterogeneous GIS software in grid environment, studied the grid computing technology of spatial information, broke through the key technologies of grid GIS, and developed high-performance and high-availability grid GIS application service software and integrated application system.

The related standards of grid GIS have been well applied in projects such as "Information Grid Platform of China Geological Survey" and "Sky Map". Grid GIS platform has been applied to geological survey information grid, digital city, geographic information public service platform, digital river basin, digital oil field and other platforms. Grid GIS spatial analysis and processing technology has been applied to forestry informatization construction, coal mine safety system and earthquake emergency command system construction.

It can be considered that grid GIS is an organic combination of GIS and grid technology, and it is the application of GIS in grid environment. Grid GIS grid environment must be able to run on the latest software and hardware technology platform, and finally realize GIS grid. Through grid technology, GIS has expanded its functions and truly become an information tool used by the public. From any node on the grid, all kinds of distributed geospatial data and attribute data with hypermedia characteristics on the grid can be accessed, and geospatial analysis and query can be carried out, and complex spatial problems can be calculated in parallel to assist and support decision-making.