Improvement on Timestamp-based User Authentication Scheme with Smart Card Lost Attack Resistance

Smart card-based user authentication is a useful mechanism for performing private session over an insecure network. Tang et al have proposed a robust and efficient scheme in 2013 that is based on elliptic curve discrete logarithm problem (ECDLP). It is for eliminating the attack in Awasthi et al’s scheme. However, Tang et al’s scheme is still vulnerable to denial of service attack and off-line password guessing attack. In this paper, the weakness of Tang et al’s scheme is presented. Furthermore, it gives the improvement of Tang et al’s scheme, and is proposed for avoiding the possible attack in Tang et al’s scheme.