An improved mechanism for four-way handshake procedure in IEEE802.11i

With the development of WLAN (wireless local area network), the security problems become more apparent than before. 802.11i protocol enhances the security performance such as encryption and authentication, however, the four-way handshake procedure aiming to produce the PTK (pairwise transient key) is subjected to the DoS attack and the DoS flooding attack, which may result in memory exhaustion. Cookie mechanism is reviewed for its robustness against the DoS attack and the DoS flooding attack. After analyzing the Cookie mechanism, some weaknesses such as the exposure of the PTK are found. Thus, an improved mechanism is proposed, without exposing the PTK in the wireless space directly, this new mechanism performs great to avoid the DOS attack and to decrease the transmission load.