A Novel Untraceable Authentication Scheme for Mobile Roaming in GLOMONET

In global mobile network, it is required to authenticate mobile users, provide secure communication channel between a user and a foreign agent using session key, and guarantee users’ anonymity and untraceability. In order to improve the security of mobile roaming service, twofactor authentication which employs smart card and password was introduced to global mobile network. In 2014, Kuo et al. [5] proposed an anonymous two-factor authentication scheme for mobile roaming service. However, we found that this scheme is vulnerable to four kinds of manin-the-middle attacks and denial-of-service attack. In this paper, we first review Kuo et al.’s scheme and analyze its weaknesses. Then, we propose an efficient anonymous two-factor authentication protocol that overcomes those vulnerabilities in Kuo et al.’s.