Towards integrated geographical information processing

Abstract

Many geographical applications access data from multiple disparate repositories such as file systems, Geographical Information Systems and database management systems which contan data able to be interrelated. Existing approaches that either built a single repository that contained all the required data or simply interconnect these repositories have not been well received. In this paper, we present the design of the Virtual GIS, a system for distributed spatial data processing in heterogeneous environments. The Virtual GIS is an integrated system that provides all the essential facilities or integrating and retrieving data from multiple component systems. The system is particularly aimed at extensibility and scalability through distributing the processing load across the component systems and a global frontend. The object-oriented data model is adopted as a common data model to ensure meaningful data sharing. We also employ the five-level schema architecture of Sheth and Larson as the framework for system integration. Finally, queries are processed using a five-phase query processing approach.