Prevention of 4-way handshake blocking in IEEE 802.1 li by an statistical method and changing Message3

This paper focuses on IEEE 802.11i that is the last released security standard for WLAN and tries to resolve bugs of previous security standards in wireless networks, but it is vulnerable against some DOS (Denial of Service) attacks. One of the attacks that is considered in this paper happens in the last phase of the authentication process called 4-way handshake blocking. In this paper, in order to prevent the DOS attack we propose two solutions; first one is a new statistical method against abnormally increase of Message1 and another solution changes Message3- one of the messages in 4-way handshake phase-. We use C#.Net 2010 programming Language to implement 802.11i platform and then solutions and final results will be compared together.