基于XML—RPC的分布式地理信息系统计算模型

分布式异构 GIS系统集成与互操作是 GIS应用发展的趋势和方向 .在 WMS(Web Map Service)和 GML研究的基础上 ,采用 XML 技术和客户机 /服务器通用分布式计算模型 ,提出了一种基于 XML RPC的分布式 GIS计算模型 ;基于 XML- RPC模型 ,设计了分布式 GIS系统中基本 GIS操作和 GIS数据资源的 XML 抽象与表达 ;抽象出了 L og In、L og Out、Get Capability、Get Map、Get Ftr Info、Get Sel Ftrs、Get Them e Map、Get Stat Map 等 8个Geo Processing元操作 ;定义了各个元操作的 XML- RPC请求与响应的 XML 数据格式协议 ,并实现了一个简化的原型系统从而验证了该模型的技术可行性、实用性 ,为第 2代 Web GIS的产品化奠定了理论模型和技术基础

A Study on XML-RPC Based Distributed Computing Model of Internet GIS

The integration and interoperation of distributed inhomogeneity GIS system is the direction of GIS development. Based on the reserach of WMS(Web Map Service), WFS(Web Feature Service) and GML, this paper presented a new XML RPC based distributed computing model of internet GIS. The Model is composed of three tiers, the diverse geo processing of geo processing enabled client, the GIS distributed computing mid ware and the geo processing server. XML RPC is used to carry out the communication between geo processing client and geo processing server by GIS distributed computing mid ware. Login?Logout?GetCapability?GetCapability?GetMap?GetFtrInfo?GetSelFtrs?GetThemeMap?GetStatMap are defined as the basic GIS computing command in XML. GML 2 0 is used to present the geo spatial data and geo processing result. The geo processing sever may implement the XML RPC interface directly, such as Web Map Serve, or use a adapter to encapsulate the geo processing service. The geo processing client uses these basic commands and their combination to call the geo processing service. The geo processing sever execute the geo processing using its own geo spatial data, application model and computing resources. Then the geo processing client receives the geo processing results as image stream and/or feature stream encoded in GML 2 0 and thus integrate the distributed inhomogeneous geo processing server system.s