Enhancement of two-factor authenticated key exchange protocols in public wireless LANs

In 2008, Juang and Wu proposed two authenticated key exchange protocols by improving Park and Park's two-factor authenticated key exchange protocol in public wireless LANs. They pointed out that Park's protocol was vulnerable to the dictionary attack on the identity protection. The improved protocols requires fewer exchanged messages and provided more secure protection for the client's identity. In this paper, we propose two protocols require less exchanged messages than Juang's protocols. In addition to this advantage, we point out that the identity protection of Juang's protocol is computationally inefficient for the server and efficient identity protection is proposed in the second proposed protocol.