Research On Encryption And Decryption Based On A File System Filter Driver For Vector Map

As an important carrier of the geographic information, digital vector map is one of themost active computer geographic information areas of application in recent years. It has beenwidely applied in many fields, like the military and national defense, the ecological andenvironmental protection and digital cities. However, it is followed by the vector map’s dataprotection and the copyright management, and the producers want to avoid the illegal use ofdata and unauthorized copying and distribution completely. Therefore, how to ensure digitalvector map safety, and cut off the way of leak, is the relentless pursuit of domestic and foreignresearchers.Traditional encryption software technology can solve the security problem of vector mapfiles, but it can not achieve a better balance between data security and efficiency. In this paper,the data access principles and mechanisms of geographic information products had beenstudied, and geographic information products encryption policy for the implementation ofdrivers had been developed. Using the file system filter driver technology and encryptiontechnology, encryption/decryption process had been inserted into the data channel betweendisk media and the display. This paper system succeeded in providing transparent encryption/decryption services for vector map files. A variety of symmetric encryption algorithms hadbeen used for the vector map file encryption, and an asymmetric encryption algorithm hadbeen used for the encryption key.In this paper, a transparent encryption model based on file filter driver was proposed, andit provided a complete set of security protection. Complete encryption system was used toensure the plaintext data security of a transparent decryption during normal use, and theasymmetric encryption algorithm was used for the encryption key to ensure the safety of thevector-map ciphertext data, starting from the source, to keep the vector map data away frommalicious leak. At the time of transparent encryption, copyright information is embedded intovector map products, so that producers and publishers can take strict monitor of the path ofthe maps’ transmission. Encryption/decryption process is transparent to users, and usersdon’t need to know the specific details. It improved data security and user experience greatly.Transparent encryption model needs some special treatment to the memory-mapped andfile buffering mechanism provided by the Windows operating system. It takes refreshing cache and double cache technology to solve the leak problems that are caused by the shiftbetween legal process and illegal process.