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:
Sep. 24, 2002
Filed:
Jul. 20, 2000
Yasuhiro Nakamura, Tokyo, JP;
Seiji Hiraka, Iwate, JP;
Kazunori Asada, Hokkaido, JP;
Satoshi Era, Hokkaido, JP;
Tokyo Electron Device Limited, Yokohama, JP;
Abstract
A storage device ( ) has a flash memory ( ), a controller ( ) and a second ROM ( ). In the flash memory ( ), a data key is stored, which is a key unique to each storage device ( ). In the second ROM ( ), a system key is stored which is an encrypting key common to storage devices ( ). The controller ( ), when writing data, encrypts the data with the data and system keys and writes the encrypted data in the flash memory ( ), and when reading data, decrypts the data with the data and system keys to output the decrypted data. The data key may be encrypted with the system key. In this case, when to write data, the controller ( ) may decrypt the data key with the system key, and encrypt data with the decrypted key, and when to read data, the controller may decrypt the data key with the system key, and decrypt the encrypted data with the decrypted data key.