A Remote User Authentication Scheme Preserving User Anonymity and Traceability

Many smart card based remote authentication schemes have been proposed to preserve user privacy against eavesdropper. However, none of the exiting scheme provides both users´ anonymity to server and traceability to the malicious user. In this paper, we present a scheme that preserve user anonymity not only against outside attackers, but also against the remote server. When a malicious user was found, server can trace the user with the help of the trusted third party.