Research On Information Protection For Vector-map

With the development of computers and networks , electronic documents have been part of people's daily lives. Digital vector maps have been widely used in military defense,environment and other aspects, for its rich content , zooming and precise positioning without distortion characteristics . However, because of the high cost and difficulty of vector mapping ,the protection of copyright and vector map data for corporate interests and national security has a profound meaning.This article researches vector map files for data encryption and access control based on file system filter driver technology. Forming a protection technology for vector map based on file system filter driver . The technical works in Windows kernel layer . And in a filter layer the file data encryption and decryption , and access control will be done transparently and forcibly. And the encryption identification , and access control information are added to the extensional tail of the file , thus ensuring that the vector-map file and the control information are together, and the vector map will not be damaged when the file is copied or transferred.Inside the driver, the driver maintains the real file size and offset to ensure that the document literacy is not affected by the extensional tail of the file and the user can read and write file correctly. Also the driver use the information such as legal process, access time and access control, to control the vector map files in the operation system kernel.Finally this system is able to prohibit the illegal process to read the right vector map file data, and control the file open time and number for the legal process. When opening times achieve the required number of visits , the file will be automatically deleted. This prevents frequent access to the file, and improves the safety factor. For no processed vector map files ,which exit in the computer before loading the driver, the system will encrypt the file data and add the access control information after its first open by a legal process. Thus ensuring the vector map data can not be copied into the old file to leak .