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:
Nov. 23, 2010
Filed:
Sep. 21, 2005
Tomoya Sato, Nara, JP;
Makoto Fujiwara, Kyoto, JP;
Tomoya Sato, Nara, JP;
Makoto Fujiwara, Kyoto, JP;
Panasonic Corporation, Osaka, JP;
Abstract
In order to maintain the confidentiality of information at a high level even in cases where a confidential information processor in which multiple types of decryption sequences are applicable is used, decryption is performed according to the value of content decryption information. If the value of the content decryption informationis '0', an encrypted content keyis decrypted with a selected authentication intermediate keyand encrypted contentsare decrypted with a content key. On the other hand, if the value of the content decryption informationis other than '0', the selected authentication intermediate keyis converted by performing an arithmetic operation using that value, thereby generating a conversion intermediate key. An encrypted domain keyis decrypted with the conversion intermediate key, the encrypted content keyis decrypted with a domain key, and then the encrypted contentsare decrypted with a content key