To enable an entity which controls a public key infrastructure to perform active control.
A user information storage section 170 stores user information. A certificate information storage section 180 stores certificate information. A certificate storage section 250 stores a public key certificate. An information comparison section 110 determines whether or not the public key certificate should be reissued. A reissue instruction sending section 120 sends a certificate reissue instruction if the public key certificate should be reissued. An authentication request sending section 210 sends a certificate authentication request. An authentication section 130 sends an authentication result. A reissue request sending section 220 sends a certificate reissue request if the authentication is successful. A new certificate issue section 140 issues a new public key certificate. A new certificate storage section 230 stores the new public key certificate. An old certificate revocation section 150 updates the certificate information to a revocation state. A deletion instruction sending section 160 sends a certificate deletion instruction. An old certificate deletion section 240 deletes the public key certificate.
SUGANUMA TOMOHISA
OGA SHOGO
MORISHITA KOJI
Yukio Nakamura
Yoshimura Munehiro
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