Abstract: The present invention provides a method of validating a certificate by a certificate validation server using certificate policy and certificate policy mapping in a public key infrastructure (PKI). If the certificate validation server receives, from a client, an object certificate to be validated, a certificate of a certification authority which the client trusts, and a certificate policy which will be applied to validation of the object certificate, and receives a request for validation of the object certificate, the certificate validation server creates a certification path for the object certificate in response to the request. The certificate validation server validates the created certification path using a certificate policy mapping table if the validation of the object certificate is allowed, and then transmits a result message to the client according to the result of the validation of the certification path.

Abstract: The present invention provides a method for modifying validity of a certificate in a public key infrastructure (PKI)-based authentication system, which is capable of performing online suspension, recovery and revocation of a certificate between a user system and a certificate authority by executing user authentication with guaranteed reliability using user biometric information. Accordingly, there is no need for the user to personally visit a registration authority or certificate authority to modify the certificate validity. The user can easily modify the certificate validity using his/her user system connected online to the certificate authority.

Abstract: A portable USB storage device includes a case, a USB port, and a control device. The case contains therein a data storage. The USB port can be inputted into the case in a sliding motion. The control device selectively controls a location of the USB port to keep the USB port.

Abstract: A portable USB storage device includes a case, a USB port, and a control device. The case contains therein a data storage. The USB port can be inputted into the case in a sliding motion. The control device selectively controls a location of the USB port to keep the USB port.

Abstract: The present invention provides a method of validating a certificate by a certificate validation server using certificate policy and certificate policy mapping in a public key infrastructure (PKI). If the certificate validation server receives, from a client, an object certificate to be validated, a certificate of a certification authority which the client trusts, and a certificate policy which will be applied to validation of the object certificate, and receives a request for validation of the object certificate, the certificate validation server creates a certification path for the object certificate in response to the request. The certificate validation server validates the created certification path using a certificate policy mapping table if the validation of the object certificate is allowed, and then transmits a result message to the client according to the result of the validation of the certification path.

Abstract: A method for issuing a certificate using biometric information in a public key infrastructure-based authentication system is provided. In the present invention, an authentication code used to protect a certificate issuance request message is assigned to a user by a certificate authority not at a registration step but at a certificate issuance request step where a user authentication is performed with user's biometric information. Therefore, there is no need for a user to remember and enter the complex authentication code to be issued the certificate, thereby simplifying certificate issuance procedures. Further, in the present invention, the authentication code is assigned to the user at the certificate issuance step only after a real-time authentication using the user's biometric information is performed.

Abstract: The present invention provides a method for modifying validity of a certificate in a public key infrastructure (PKI)-based authentication system, which is capable of performing online suspension, recovery and revocation of a certificate between a user system and a certificate authority by executing user authentication with guaranteed reliability using user biometric information. Accordingly, there is no need for the user to personally visit a registration authority or certificate authority to modify the certificate validity. The user can easily modify the certificate validity using his/her user system connected online to the certificate authority.