A lightweight anonymous authentication scheme for consumer roaming in ubiquitous networks with provable security

Ubiquitous networks provide roaming service for mobile nodes enabling them to use the services extended by their home networks in a foreign network. A mutual authentication scheme between the roamed mobile node and the foreign network is needed to be performed through the home network. Various authentication schemes have been developed for such networks, but most of them failed to achieve security in parallel to computational efficiency. Recently, Shin et al. and Wen et al. separately proposed two efficient authentication schemes for roaming service in ubiquitous networks. Both argued their schemes to satisfy all the security requirements for such systems. However, in this paper, we show that Shin et al.'s scheme is susceptible to: (i) user traceability; (ii) user impersonation; (iii) service provider impersonation attacks; and (iv) session key disclosure. Furthermore, we show that Wen et al.'s scheme is also insecure against: (i) session key disclosure; and (ii) known session key attacks. To conquer the security problems, we propose an improved authentication scheme with anonymity for consumer roaming in ubiquitous networks. The proposed scheme not only improved the security but also retained a lower computational cost as compared with existing schemes. We prove the security of proposed scheme in random oracle model. Copyright (C) 2015 John Wiley & Sons, Ltd.