SYSTEM AND METHOD FOR ISSUING PUBLIC KEY CERTIFICATE, INFORMATION PROCESSOR, INFORMATION RECORDING MEDIUM, AND PROGRAM STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a configuration which enables devices capable of performing different signature algorithm processes to mutually verify a public key certificate. SOLUTION: A public key certificate having multiple signatures based upon various signature systems such as RSA and ECC is issued and a device selects a signature that the device can process (verify) and performs a verifying process. Devices which can verify only different signature algorithms, therefore, become able to verify open-key certificates of the opposite sides and mutual certification between this device and not only a device having a public key certificate having an added public key certificate of the same specific signature algorithm with this device, but also a device or provider having a public key certificate with a signature by a different signature algorithm and the verification of a public key certificate in ciphered data communication can be performed to increase the reliability of the communication.