A Mobile Intelligent Terminal Based Anonymous Authenticated Key Exchange Protocol for Roaming Service in Global Mobility Networks

With the rapid development of mobile intelligent terminals, users can conveniently enjoy ubiquitous services in global mobility networks. User authentication and user privacy protection are two important issues for providing secure roaming service in global mobility networks. Until now, many authentication protocols for roaming service with user anonymity are proposed. Unfortunately, most of the existing protocols only have heuristic informal security arguments. Moreover, current works only achieve weak anonymity. A user's identity is only anonymous against eavesdroppers and is known to the home agent and sometimes even the foreign agent. In order to overcome these weaknesses, we propose a privacy-preserving password-authenticated key exchange protocol for roaming service in global mobility networks. The proposed protocol is proven secure in the random oracle model under the CDH and the $q$ q -SDH assumptions. Our protocol achieves stronger user anonymity than other related protocols. The performance comparison shows that our protocol is more efficient in terms of on-line computation and enjoys optimal communication complexity. Consequently, it is more suitable for real applications in global mobility networks.