Hitachi, Ltd.

Yoko Kumagai

Takahiro Fujishiro

Tadashi Kaji

Shingo Hane

Satoru Tezuka

Hitoshi Shimonosono

Yutaka Miyazaki

Tomoharu Morio

Takanobu Oikawa

Izumi Anayama

Hiromi Nagano

A validation authority for certificates searches for and verifies paths and certificate revocation lists periodically, and classifies the paths into valid paths and invalid paths in accordance with the results of the validations, so as to register the paths in databases beforehand. Besides, in a case where a request for authenticating the validity of a certificate has been received from an end entity, the validation authority judges the validity of the public key certificate by checking in which of the valid-path database and the invalid-path database a path corresponding to the request is registered. On the other hand, in a case where the path corresponding to the validity authentication request is not registered in either of the databases, the validity of the public key certificate is authenticated by performing path search and validation anew.

Method, product and apparatus for accelerating public-key certificate validation

Method and apparatus for accelerating public-key certificate validation

In response to a sign request including a digital document from a document-creating device, a digital-signed-document exchange supporting servercanonicalizes the digital document, calculates a digest value thereof, and returns the digest value to the document creating device. When the document-creating device transmits a digital sign created by encrypting the digest value to the digital-signed-digital document exchange-supporting server, the servercreates a digital-signed document from the digital sign and the digital document, and returns the document to the document-creating device. On the other hand, in response to a validation request including a digital-signed-digital document and a public key from a sign validating device, the servercompares a value resulting from the decryption of the digital sign with the public key and a digest value of the digital document canonicalized and returns the result to the sign validating device.

Digital-signed digital document exchange supporting method and information processor

A time period which is expended since a request for the authentication of the validity of a public key certificate till the authentication of the validity, is shortened. A certificate validity authentication center VC periodically searches for and verifies paths which extend from a bridge certification authority CAto individual terminal admitting certification authorities CA, and it registers the paths whose verifications have held good, in a path database in association with the respective terminal admitting certification authorities CA. Besides, in a case where the request for the authentication of the validity of a certificate has been made by an end entity EE, whether or not a path associated with the terminal admitting certification authority CA which admits the end entity, and a path associated with the terminal admitting certification authority CA which has issued the certificate being a subject for the request are registered in the path database is checked, and the subject certificate is judged valid only when both the paths are registered.

Certificate validity authentication method and apparatus

A public key certificate generation method includes the steps of: sending a certificate issuing request including a registration contents of a public key certificate and an information content guaranteed by the registration authority, to the issuing authority in a registration authority and generating a public key certificate including the registration contents described in the certificate issuing request the information guaranteed by the registration authority issuing contents issued by the issuing authority, and a signature to the issuing contents in the issuing authority.

Public key certificate generation method, validation method and apparatus thereof

If a CRL is cached for an increased speed of a certificate validation process, when a certification authority issues a CRL in an urgent situation, the accuracy of the certificate validation result cannot be secured because the cached CRL is not the latest one. This problem is solved as follows. When it issues a CRL, the certification authority sends a CRL issuance notification to certificate validation servers. The certificate validation servers that received the CRL issuance notification cache the latest CRL. Thus, the accuracy of the certificate validation result can be secured.

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Tokyo, Japan

Yoko Kumagai