Patent ID: 6389536
Filing Date: 2002-05-14
Classification: G06F,G06Q,G07F

Abstract:
A use qualification verification device comprising a proof support information issuance unit, a verification unit, and a proof unit,wherein said proof support information issuance unit comprises: a proof information management part that manages proof information used for authentication of use qualifications; a private information management part that manages private information; a first unidirectional function computation part that, to at least private information managed by said private information management part, applies a unidirectional function whose inverse function is at least computationally difficult to obtain; a proof support information computation part that computes proof support information, based on private information managed by said private information management part and a computation result of said first unidirectional function computation part; and a first communication part that sends and receives information in the process of computation of proof support information; wherein said verification unit comprises: a proof information memory part that stores proof information; a challenge information computation part that computes challenge information; a second unidirectional function computation part that applies a unidirectional function whose inverse function is at least computationally difficult to obtain; a response information verification part that lets said second unidirectional function computation part act on the proof information stored in said proof information memory unit and a value obtained based on a part or all of the challenge information and checks whether an obtained result and the response information are equal; and a second communication part that sends and receives information in the process of authentication of use qualifications; and wherein said proof unit comprises: a private information memory part that stores private information; a proof support information management part that manages proof support information used to compute response information; a third unidirectional function computation part that applies a unidirectional function whose inverse function is at least computationally difficult to obtain; a response information computation part that lets said third unidirectional function computation part act on a part or all of the challenge information, the private information stored in said private information memory part, and a value obtained based on the proof support information managed by said proof support information management part to compute response information; and a third communication part that sends and receives information in the process of authentication of use qualifications and in the process of proof support information computation.