Patent ID: 7366904

Claim:
A method for modifying validity of a certificate using biometric information in a public key infrastructure-based authentication system including a registration authority for verifying identity of at least one user by proxy, a certificate authority for issuing the identity-verified user with the certificate and a user system, the method comprising the steps of: a) accessing a server of the certificate authority using login information of the user in response to a certificate validity modification request from the user under the condition that he/she is registered as a member in the authentication system; b) inputting the biometric information for a user authentication through a biometric information input unit in the user system; c) generating a certificate validity modification request message in response to the certificate validity modification request from the user, wherein generating a certificate validity modification request message includes one of: generating a certificate revocation request message revoking the certificate issued to the user; generating a certificate suspension request message suspending the certificate issued to the user; and generating a certificate recovery request message recovering suspended authority of the certificate of the user; and d) sending the inputted biometric information and the generated certificate validity modification request message to the certificate authority to request the certificate validity modification online.