An efficient mutual authentication and key agreement protocol preserving user anonymity in mobile networks

We address the problem of mutual authentication and key agreement with user anonymity for mobile networks. Recently, Lee et al. proposed such a scheme, which is claimed to be a slight modification of, but a security enhancement on Zhu et al.’s scheme based on the smart card. In this paper, however, we reveal that both schemes still suffer from certain weaknesses which have been previously overlooked, and thus are far from the desired security. We then propose a new protocol which is immune to various known types of attacks. Analysis shows that, while achieving identity anonymity, key agreement fairness, and user friendliness, our scheme is still cost-efficient for a general mobile node.