Abstract
Recent evolution in the open access internet technology demands that the identifying information of a user must be protected. Authentication is a prerequisite to ensure the protection of user identification. To improve Qu et al.' s scheme for remote user authentication, a recent proposal has been published by Huang et al., which presents a key agreement protocol in combination with ECC. It has been claimed that Huang et al. proposal is more robust and provides improved security. However, in the light of our experiment, it has been observed that Huang et al.' s proposal is breakable in case of user impersonation. Moreover, this paper presents an improved scheme to overcome the limitations of Huang et al.' s scheme. Security of the proposed scheme is evaluated using the well-known random oracle model. In comparison with Huang et al.' s protocol, the proposed scheme is lightweight with improved security.