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:
May. 10, 2011
Filed:
Jun. 30, 2005
Tohru Nakahara, Osaka, JP;
Ryuichi Okamoto, Osaka, JP;
Masaya Yamamoto, Osaka, JP;
Katsumi Tokuda, Osaka, JP;
Masaya Miyazaki, Osaka, JP;
Masayuki Kozuka, Osaka, JP;
Tohru Nakahara, Osaka, JP;
Ryuichi Okamoto, Osaka, JP;
Masaya Yamamoto, Osaka, JP;
Katsumi Tokuda, Osaka, JP;
Masaya Miyazaki, Osaka, JP;
Masayuki Kozuka, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A content playback apparatus reduces load concentration on a specific server apparatus that manages content keys of encrypted content, while protecting copyrights of the content. The content apparatus makes playback of content recorded in a recording medium sold possible after the specific server breaks down. A key acquisition control unit () reads a playback control information table () from a recording medium () via a reading unit (). The key acquisition unit () acquires a rights key via a key acquisition intermediation unit () from an apparatus specified by an acquisition-destination type and a request-destination type that are stored in the playback control information table () and that corresponding to the content to be played. The key acquisition unit () generates a content key using the acquired rights key and, when required, a medium key recorded in a medium. A decryption unit () decrypts encrypted content using the content key.