An efficient and practicable anonymous authentication scheme using smart cards

Recently, many smart card-based anonymous authentication schemes have been proposed to preserve user's anonymity. Unfortunately, most of these schemes do not achieve to preserve user's anonymity from the malicious user. In 2008, Kim et al. proposed a scheme which not only guaranteed user privacy but also provided traceable anonymity authentication. In this paper, we first point out that Kim et al.'s scheme still does not provide user anonymity as they claimed, then we highlight the inherent design flaw of Kim et al.'s scheme and the previous ones failing to protect user's anonymity. Finally an efficient anonymous authentication scheme is proposed to solve these aforementioned problems.