An Improved Anonymous Authentication Scheme for Roaming Services

In wireless network and mobile network, a two-factor authentication scheme for roaming services enables a mobile user to achieve mutual authentication and key agreement with the foreign agent. In this paper, we review Kim et al.’s anonymous authentication scheme in global mobility networks. Analysis shows that Kim et al.’s scheme fails to achieve anonymity and two-factor authentication. In addition, Kim et al.’s scheme is vulnerable to impersonation attacks. It is also inconvenient for a mobile user since the mobile user cannot update password freely. We then propose a secure anonymous authentication scheme. Our proposed scheme satisfies six properties of secure authentication schemes for roaming services.