The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 12, 2009
Filed:
Jan. 31, 2005
Yoko Kumagai, Tokyo, JP;
Takahiro Fujishiro, Yokohama, JP;
Tadashi Kaji, Yokohama, JP;
Shingo Hane, Yokohama, JP;
Hitoshi Shimonosono, Funabashi, JP;
Yoko Kumagai, Tokyo, JP;
Takahiro Fujishiro, Yokohama, JP;
Tadashi Kaji, Yokohama, JP;
Shingo Hane, Yokohama, JP;
Hitoshi Shimonosono, Funabashi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
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.