Research And Implementation Of LAN Data Security System

As one kind of general platform for sharing resources, the LAN(local area network) is widely used nowadays. The popularization of LAN has provided the great advantage for making good using of resources reasonably and enhancing the efficiency in office. But at the same time, the problem of data security is also prominent more and more in the LAN, especially for the validated users of LAN who have no intention to divulge the sensitive data or steal on purpose.Firstly, this paper aims at the current security problems of LAN, designs and realizes a data security system for LAN. This system bases on the C/S pattern structure. It can be divided into the following parts: network access control, document sharing, document dynamic encrypting and decrypting, data security transmission, key distribution, strategy processing part and so on. The paper specifically describes the idea and realization method for the above modules, and summarized essential technology, difficulties and the innovation during the realization. At the last after the encrypting and decrypting performance test for this system, it can be indicated that the system's encryption and decryption in the kernel-mode could not affect users' operation in the user-mode.The deeper study and research about the network driver monitoring network activities and the file system filter driver monitoring file operations are developed with emphasis. According to the thorough analysis about the technology of HOOK PE, network connection monitoring and encryption transmission for the sharing data are realized with NDIS-HOOK. And then the paper studied the recognition about volume equipment and file encryption mark processing in the file system filter driver, and realizes file dynamic encryption and decryption module.In the end this paper puts forward some improvement and prospects about the following research direction and the further work.