Improvement, Based On Wireless Local Area Network Wlan Security Protocol Of The Management Frame

With the development of the communications technology, the proportion of the net in the people's life become larger, and the development of the wireless communication and Internet technology bring more advantage to the fashion and the quality of our life. More and more mobile telephone has the function of login net. Wireless Local Area Network become one of the important directs of the modern wireless communication because its motion ability and transmission speed.WLAN is the supplement and extend of the wire net, in the same time, it should satisfy the requirement and restrict of its motion, and the biggest question is security. Because the wireless electric wave is open, the request security of WLAN is higher than the request of wire net, because the physical control method of wire net can not be put into the WLAN. So the security problem of wireless net become the research keystone.The research analyzes IEEE802.11 standard generally, and the structure of WLAN, and WEP, WPA, WAPI as well. After that, this paper points out unsecured aspects of the standard and different kinds of attack..This paper analyzes function of management frames, structure and classification. After analysis of attacks relating to management frame, this paper proposes a new model based on management authentication and encryption. This research bases the proposed model on using the HMAC-SHA1 algorithm to protect management frames. According to the proposed model, when a sender wants to send each kind of management frame, first by using HMAC-SHA1 algorithm, key, header and body of the MF, the Sender Code (Scode) is computed and is connected to the MF then this new protected MF is transmitted. When receiver takes this protected MF, first computes Receiver Code (Rcode), by using the received MF, k and HMAC-SHA1 algorithm. If Scode and Rcode match together, so no data is changed, and the sender is legitimate. If not, that means the data transmission was compromised by some kind of attack, and the data was changed. Simulation methodology is presented and results are provided as well. Mathematical probabilities are discussed to demonstrate that the proposed security model is efficient than IEEE802.11a and IEEE802.11b, which are currently widely used.