Research On Access Control Of Geographic Information Services

Geographic Information Services has become the mainstream technology of GIS cross-platform applications. It increasingly spreads to most areas of society and greatly enhances the sharing of geographic information. The geographic information sharing does not mean unfettered use of spatial data, so the premise of sharing is to guarantee the data security. However, the security mechanism of geographic information services is still relatively weak, and difficult to meet the security needs of data sharing. As an important part of the security mechanism of geographic information services, Access control has important research significance.This paper summarizes the characteristics and security requirements of geographic information services, analyzes the access control policy of spatial data, then presents an access control model for Geographic information services based on existing access control modes, and finally studies key technologies. The main contents and conclusions of this paper are as follows:(1) Study on spatial data access control policy. According to the characteristics of spatial data, the access control policy on spatial data is divided to several different types, including the Data granularity-based Policy, the Scope-based Policy, the Spatial relations-based Policy, the Time-based Policy, the Scale-based Policy and so on. Then this paper analyzes the selection and combination of these policies.(2) Study on access control model of Geographic Information Services. Based on analyzing access control demands of distributed environment and spatial data, this paper extends Attribute-based Access Control Model, introduces the concepts of spatial data, and finally presents GIServices Attribute-based Access Control Model.(3) Study on the servlet filter technology. Because of web features of Geographic Information Services, this paper uses servlet filter technology to intercept, analyze, modify, and package users'requests and service responses.(4) Study on GeoXACML policy description. Based on GeoXACML(Geospatial eXtensible Access Control Markup Language), this paper research on the access control policy description of Geographic Information Services, and how to match and evaluate policies.The study on access control model and technology of Geographic Information Services will enrich the research in this field, and improve the security mechanism of Geographic Information Services.