System Implementation And Performance Enhancement Of WAPI

As its flexibility and convenience, Wireless Local Network (WLAN) is widely used in corporation, offices, airports, hospitals, and at home, or in special environment for dealing with an emergency event. However, opening wireless transmission brings some security vulnerabilities into WLAN, such as data is easily eavesdropped, intercepted and modified, Denial of Service and masquerading attacks are easily mounted.Along with the appearance of WAPI, the security problem of WLAN has been reduced to some extent. However, there is no standard way to implement the protocol for the moment, which brings some trouble to system design.On the base of grasping the idea of the way to implement general security protocols, the design principle is put forward: there are at least three rules to follow, that is, basic requirements, high security, and high performance. Through detailed analysis with the authentication process of WAPI, some key points are discussed and the design method of WAPI system is brought forward. Finally the WAPI system is implemented in modules.First, this design contains the ordered requirements of WAPI, and according to real characteristic, some more requirement are supplemented as well, such as authorization and accounting, updating multicast key when user is offline, authentication in the RADIUS way.Then, in this thesis, the defeats of WAPI are talked about and some solutions are brought to deal with them.Finally, in the implementation of WAPI protocol, SMS4 algorithm, the first commercial algorithm published by the government, is made to do the encryption work. On the base of thorough analysis with the SMS algorithm performance bottleneck, an enhancement is done to the SMS4 algorithm, which makes great improvement to the performance of WAPI system.