inbul 2004 
b Service 
Electronics 
Language 
ementation 
XML-BASED SPATIAL DATA INTEROPERABILITY ON THE INTERNET 
Yumin Chen, Jianya Gong, Wenjue Jia, Qi Zhang 
State Key Laboratory for Information Engineering in Surveying, Mapping and Remote Sensing, Wuhan University, 129 
Luoyu Road, Wuhan, HuBei, China, 430079 
KEY WORDS: 
ABSTRACT: 
Interoperability, Spatial, Data, GIS, Internet, and Services 
With the development of network and information technology, the spatial data gain, sharing, issuing and analysing plays a more and 
more important role in the decision of each department. This article discusses the method of the spatial data interoperability based on 
XML; thoroughly compares two kinds of applications standard in the specialized domains of XML—GML(Geography Mark-up 
Language) standard and SVG(Scalable Vector Graphics) standard. Considered their different characteristic, the spatial data 
interoperability system based on GML and SVG has been designed and practiced. GML is chosen to take the spatial data storage and 
transport standard, however there is not a general tool to show the GML map, so it can be changed to SVG format and browse the map 
through the plug-in of SVG Viewer. The four- layer structure of the application system is designed, that is the Database Server, the 
Web Services, the Web application Server and the Client. The implementation system is supporting XML and the surrounding web 
services technology. The result is satisfied and the technology on spatial data interoperation based on XML will have wide 
development prospects. 
1. INTRODUCTION 
With the development of network and information technology, 
the spatial data gain, sharing, issuing and analysing plays a more 
and more important role in the decision of each department. A 
lot of database have been built base on the traditional GIS 
platforms (such as ArcInfo software in early stage) by all 
departments now. Geographic datasets are increasingly being 
shared, exchanged, and used for purposes other than their 
producers’ intended ones. How to useful implement spatial data 
sharing and interoperability is the key problem in the GIS field. 
The OGC addressed the issue of standards in GIS so that data 
and information from numerous sources can be integrated with 
the capabilities of GIS for the development of various 
applications. In their study, they define the specification and 
interfaces that are. connecting GIS for data processing. Web 
services are building blocks for creating open distributed 
systems. Web services may be an evolutionary step in designing 
distributed applications, and communicate using HTTP and 
XML (Extensible Mark-up Language). 
This article discusses the method of the spatial data 
interoperability based on XML; thoroughly compares two kinds 
of applications standard in the specialized domains of XML— 
167 
GML(Geography | Mark-up standard and 
SVG(Scalable Vector Graphics) standard. Considered their 
Language) 
different characteristic, the spatial data interoperability system 
based on GML and SVG has been designed and practiced. The 
spatial data come form three different platforms, that is ArcInfo 
software, Geostar software and GeoSurf software, can be shared 
and interoperated successfully. 
2. SPATIAL DATA MARKUP LANGUAGE BASED ON 
XML 
XML is the new standard for the data expression and data 
exchange on Internet, and also, just the character of XML makes 
the Web integration possible. Therefore, and device, which 
supports these technologies, can both host and access Web 
services. 
GML is an XML encoding for the spatial data storage and 
transport standard, because it provides an open, vendor-neutral 
framework for the definition of reference systems and units of 
measure for geo-spatial information, and geographic application 
schemas and objects. It defines geo-spatial features with 
geometry, geo-spatial coverage, and allows profiles that support 
proper subsets of GML framework descriptive capabilities. It is 
enable the creation and maintenance of linked geographic