A robust authentication scheme for telecare medical information systems

Abstract

With the speedy progress in technology, the Internet has become a non-separable part of human life. It is obvious to use the Internet in all fields and medical field is no exception. The concept of establishing telecare medicine information systems(TMIS) for patients is gaining more popularity recently. To ensure the privacy of patients and to allow authorized access to remote medical servers, many authentication schemes have been proposed. Li et al., in 2016, proposed a secure dynamic identity and chaotic maps based user authentication and key agreement scheme. They claimed that the scheme is resistant to most of the known attacks. However, from thorough cryptanalysis, we have proved that their scheme is vulnerable to user impersonation attack, password guessing attack and server impersonation attack. We have also illustrated that their scheme does not provide user anonymity, convenient smart card revocation and security to session key. To overcome the aforementioned security weaknesses, we have proposed an enhanced authentication scheme using chaotic maps, which has been discussed in this paper along with its cryptanalysis. Cryptanalysis of the proposed scheme proves that the scheme is more robust and suitable for implementation.