A Visual Geospatial Information Server (VGIS) Providing Transparent Access to Heterogeneous Sources

Geospatial information has been realized as a valuable resource for more and more organizations and departments. Recently, developments of new techniques in worldwide high-speed network communications and applications make it increasingly possible for computer-based information systems to access a diversity of autonomous and remote information sources. The availability of various Internet information servers and browsing tools further promote information sharing across departmental, organizational, and national boundaries. However, since the development of the earliest recording and storage technologies in the GIS field, considerable efforts have had to be placed on data format translations and standardized data development so that applications in one organization can make use of geospatial data maintained by other organizations. This is because of the proprietary data models and representation methods of various geospatial information systems used by different communities. With the increasing removal of proprietary restrictions on geospatial data sources by providers and with the information consumer’s increasing need to import geodata, the interoperability of heterogeneous geospatial data sources must be achieved