An improvement of secure authentication scheme with full anonymity for wireless communications

Recently, Wu et al. proposed an efficient way to improve Zhu-Ma's protocol. Zeng et al. pointed out a security issue that the property of anonymity cannot be preserved in Zhu-Ma and Wu et al.'s schemes. That means one of the parameters in the authentication message is fixed so that a foreign agent could learn that some authentication requests actually come from the same mobile user. In this paper, we solve these problems and propose an enhanced scheme that can not only preserve the original papers' properties, but also achieve the property of full anonymity.