Attacks and solutions on Aydos-Savas-Koc´s wireless authentication protocol

M. Aydos, B. Savas and C.K. Koc (see Proc. 2nd Int. Workshop on Discrete Algorithms and Methods for Mobile Computing and Commun., 1998) proposed a wireless authentication and key agreement protocol (ASK-WAP) based on elliptic curve cryptography (ECC). We find that this protocol is vulnerable to a man-in-the-middle attack, a denial-of-service attack and an impersonation attack. We present the above mentioned attacks on the ASK-WAP. We also propose a variant of ASK-WAP, the user authentication protocol (UAP), so that it resists these attacks. Furthermore, we analyze the security and performance of the proposed UAP. The results show that our proposed UAP is much more secure and is also efficient with few message exchanges and less computation.