An assessment framework for the development of Internet GIS

The popularity of Internet technology has brought about some fundamental changes in the field of GIS. Internet GIS is emerging as a new technology to access, process, and disseminate spatial information over the Internet. Internet GIS cover a much wider audience than the traditional GIS. This raises many issues that are distinct from traditional desktop GIS, such as easy access, webcompatible user interface, and file transfer security. I will first discuss the definition and features of Internet GIS. Two major approaches used in the Internet GIS development—server-side processing and client-side processing—are then described. These approaches are compared according to their performance, user interactivity, and other criteria. The server-side approach is appropriate to provide users easy access and inquiry of large databases, whereas the client-side Internet GIS offer better user interactions. The technology of Internet GIS is evolving rapidly. It is therefore important for the GIS community to monitor and define the course of its development. Introduction The development of GIS technology has closely mirrored the development of computer technologies. It evolved from mainframe GIS in which GIS programs resided at the mainframe with terminal access, to desktop GIS in which GIS were stand-alone programs with no information exchange between computers, through to network GIS in which desktop GIS programs share data, applications, and other resources within local area networks. The recent development of the Internet technology has brought another significant change to GIS. The increasing popularity of the Internet, from online surfing to e-commerce, has made the Internet an integral part of society. The ubiquitous access to the Internet and user-friendliness of the World Wide Web (WWW) have made them a powerful means for people to exchange and process information, and to make transactions. The Internet has revolutionized ways of doing things in journalism, the sciences, publishing, and many other fields (Plewe, 1997). It is also shaping the ways in which traditional GIS function. The Internet is affecting GIS in three major areas: GIS data access; spatial information dissemination; and GIS processing. The Internet provides GIS users easy access to GIS data from different sources of data providers. GIS data warehouses and clearinghouses, and digital libraries are two common forms of Internet data access systems. The US National Geospatial Data Clearinghouse (NGDC) under the Federal Geographic Data Committee in the USA has been working to build a distributed archive of information for universal access (Peng and Nebert, 1997). The aims of the Alexandria Digital Library project is to construct a centralized or indexed repository of spatial information from diverse collections in order to make it available to the public over the Internet (Chen et al, 1997; Frew et al, 1995; Goodchild and Proctor, 1997). The Internet also enables the dissemination of GIS analysis results and spatial information to a much wider audience than is possible with traditional GIS. The general public can now directly access spatial information and see spatial patterns