Date Added: Jan 2012
Recently, many biometrics-based user authentication schemes using smart cards have been proposed to improve the security weaknesses in user authentication system. In 2006, Khan et al. proposed an improved fingerprint-based remote user authentication scheme using smart cards that is achieved mutual authentication between the user and the server, while eliminating the drawback of Lee et al.'s scheme. Later, in 2008, Xu et al. pointed out that Khan et al.'s scheme cannot withstand the parallel session attack and the impersonation attack.