The Study for Data Security Mechanism in WebGIS Based on Tile Caches

Tile caches technique creates a new release pattern of network maps which can enrich the representation form of WebGIS and dramatically decrease the loading time consumed for high quality image visualizations. However, it also makes the intellectual property rights of information not effectively protected. In order to build the data security mechanism in WebGIS based on tile caches and B/S architecture, this paper analyzed the potential data security problem in some main WebGIS from three aspects: client-code scripting, transmission of vector data and request of attribute information. The scripts usually records the calling methods of tile caches with plaintext, which makes the algorithm open and may leak the organizing structure of the tile caches; The transmission way of the vector data is included in the scripts that executed in the Browser, which makes it easy to download them from server side to client side; All the attribute information in WebGIS are classified and usually can be obtained through malicious request continuously. It also presented the corresponding measures of enhancing security mechanism, such as information hiding, digital watermarking, vector data encryption and request information restrictions. Furthermore, this paper gives the implementation of encrypting the http request and vector data using JavaScript program language. The empirical results show that these measures can avoid the data leakage and protect the data copyright effectively. The study is of special importance from the theoretical and applicative points of view.