摘要
WebGIS实现了数据的分布性,而基于中间件的网格GIS的目标是实现GIS数据和GIS功能服务的分布性。本文介绍了网格GIS的信息处理流程,并根据网格GIS对数据传输功能的要求,提出了网格GIS数据传输的实现策略。在网格GIS数据传输过程中,对地理空间数据信息的描述,是通过GML语言来完成的,并利用Web services、消息中间件等构造网格GIS数据传输服务,同时对于网格GIS数据传输中的安全问题作了阐述,利用代理机制来完成数据传输过程中的安全控制。
Data distribution of GIS has been made realism through WebGIS. With the increasing need of data sharing and GIS, WebGIS can no longer meet this requirement. The application of Grid Computing and Middleware technology in GIS make a promise for the development of Middleware Grid-GIS. Grid-GIS not only makes spatial data distributed, but also makes the functional services of GIS distributed. Grid-GIS has the following characteristics:(1) Sharing of spatial data and GIS function; (2) highly performance of computation; (3) easiness for GIS software development; (4) equity in architecture; (5) high security; and (6) easy for GIS application.In this paper the procession of data transmission was recommended, and the strategy of data transmission in Grid-GIS was put forward in order to meet the functional requirement for data transmission.In data transmission of Grid-GIS, GML was used as the description of geographic data. GML is the extending use of Extreme Markup Language (XML) in the area of Geography. Using GML user can store and transmit the attribute and location information of geographical feature. GML can describe geographical feature into text of XML format, and supply the spatial information transmission between GIS components with cogent technology.The data transmission service of Grid-GIS was constructed by taking the advantage of Web services and MO Middleware technology. Web services are a new breed of web applications. They are self-contained, self described and the modular application can be published, located and invoked across the web. Web services perform functions that can be anything from simple requests to complicated business process. Once a web service is deployed, other applications (and other web services) can discover a deployed service. Security of data transmission in Grid-GIS was also expounded. It was accomplished by using the proxy method.
出处
《地球信息科学》
CSCD
2005年第1期65-70,共6页
Geo-information Science
基金
国家"863"项目(2002AA135230)国家自然科学基金项目(40101021).
