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. 29, 2009
Filed:
Aug. 14, 2007
Osamu Shibata, Osaka, JP;
Taihei Yugawa, Nara, JP;
Tsutomu Sekibe, Osaka, JP;
Yoshiyuki Saito, Osaka, JP;
Toshihiko Otake, Hyogo, JP;
Osamu Shibata, Osaka, JP;
Taihei Yugawa, Nara, JP;
Tsutomu Sekibe, Osaka, JP;
Yoshiyuki Saito, Osaka, JP;
Toshihiko Otake, Hyogo, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A device and method for encrypting content in an encryption device including a content-key storage section is disclosed. The method includes generating a content-key used for encrypting content based on random numbers and storing the generated content-key in the content-key storage section, encrypting the content-key used for encrypting the content so as to obtain an encrypted content-key and outputting the encrypted content-key to outside of the encryption device, determining whether or not a value of the content-key storage section in its initial state and a current value of the content-key storage section are different, and when it is determined that the value of the content-key storage section in its initial state and the current value of the content-key storage section are different, encrypting the content using the current value of the content-key storage section as a content-key so as to obtain a second output data and output the second output data to outside of the encryption device, wherein, for the determination step, a register stores a value of the content-key storage section at the time that said register receives a Power On Reset (POR) signal, and wherein the POR signal is a signal which pulses only once immediately after power-on or immediately after reset, so that the content-key storage section is in an initial state immediately after a corresponding power-on or reset of the encryption device.