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:
Dec. 20, 2005
Filed:
Oct. 05, 1999
Manabu Miyatake, Kawasaki, JP;
Michio Sato, Yokohama, JP;
Manabu Miyatake, Kawasaki, JP;
Michio Sato, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a method for detecting invalid electronic storage media each storing therein identification information recognized as an invalid electronic storage medium, the individual identification information on the invalid electronic storage media, grouped by hash values, is registered as a list. On the other hand, the individual identification information and hash information are assigned to each of the electronic storage media. The method reads the individual identification information and the group value information in response to a usage request for the electronic storage medium and checks if the individual identification information on the electronic storage medium is registered with the group corresponding to the hash value that was read. If the individual identification information corresponding to the hash value is found, the method judges that the requested electronic storage medium is invalid; if the individual identification information corresponding to the hash value is not found, the method judges that the requested electronic storage medium is valid.