• identity-based cryptography;
  • handoff authentication;
  • perfect forward/backward secrecy;
  • discrete logarithm;
  • wireless network


With the rapid development of computer networks, wireless technologies find important applications in roaming communication. In this scenario, practical needs initiate the demand for a secure and efficient handoff authentication scheme. To the best of our knowledge, however, there exists no scheme that can simultaneously provide robust security properties and enjoy desirable efficiency. In this paper, we first examines the security of the scheme proposed in International Conference on Communications 2007 by Kim et al. and demonstrates that the scheme of Kim et al. fails to achieve perfect forward/backward secrecy. Furthermore, we propose a new identity-based construction for secure and efficient handoff authentication schemes, in which an identity-based online/offline encryption scheme is the primary ingredient. Compared with the scheme of Kim et al., our construction enjoys desirable efficiency in terms of the computation cost and the communication cost. To be specific, the developed scheme not only realizes a seamless handoff with key agreement, but also provides perfect forward/backward secrecy, which has never been achieved in any existing handoff-related schemes. Therefore, our construction is more suitable for handoff authentication in the wireless applications environment. Copyright © 2012 John Wiley & Sons, Ltd.