Patent Number: 6,298,153

Title: Digital signature method and information communication system and apparatus using such method

Abstract: A digital signature method including a public information generating step of generating public information specific to each user in accordance with a public parameter common to each user and secret information specific to each user, a signature generating step of generating a signature of digital information by converting the digital information by using the secret information and the public parameter, and a signature discrimination step of verifying whether a relation between the digital information and the signature is correct, by using the public parameter and the public information, has, a user information generating step of generating new secret information specific to the user, a new parameter, and new public information by using the public information, a confirmation step of confirming whether or not the new secret information, new parameter, and new public information generated by the user information generating step satisfy a predetermined relation, and an enciphering step of enciphering digital information by using the new parameter and the new public information confirmed by the confirmation step.

Inventors: Oishi; Kazuomi (Yokohama, JP)

Assignee: Canon Kabushiki Kaisha

International Classification: G06F 21/00 (20060101); G06K 009/18 ()

Expiration Date: 10/02/2018