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:
Jun. 07, 2011
Filed:
Apr. 25, 2008
Tadaoki Uesugi, Sagamihara, JP;
Takahiro Fujishiro, Yokohama, JP;
Takeshi Akutsu, Kawasaki, JP;
Hisanori Mishima, Yokohama, JP;
Tadaoki Uesugi, Sagamihara, JP;
Takahiro Fujishiro, Yokohama, JP;
Takeshi Akutsu, Kawasaki, JP;
Hisanori Mishima, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
When a document creation unitis started, it calculates a hash value of each software piece therein and stores the hash value in a hash value holderand a measurement log document holder. The document creation unitaccesses a time distribution unit plural times to receive time information therefrom, and records the time information in a log document and a measurement log document. The document creation unittransmits the log document, the measurement log document, and digital signature-embedded hash value information (measurement auxiliary document) in a tamper-resistant deviceto a document reception device. The document reception device verifies matching of the hash values or digital signature in the document group, confirms software operating environments in the document creation unitfrom the hash values, and determines whether the time information is correctly managed within the unit