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:
Mar. 27, 2012
Filed:
Apr. 30, 2008
Toshihisa Nakano, Neyagawa, JP;
Motoji Ohmori, Hirakata, JP;
Natsume Matsuzaki, Mino, JP;
Makoto Tatebayashi, Takarazuka, JP;
Naoki Yamamoto, Neyagawa, JP;
Hideshi Ishihara, Katano, JP;
Toshihisa Nakano, Neyagawa, JP;
Motoji Ohmori, Hirakata, JP;
Natsume Matsuzaki, Mino, JP;
Makoto Tatebayashi, Takarazuka, JP;
Naoki Yamamoto, Neyagawa, JP;
Hideshi Ishihara, Katano, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A content protection system prevents illegal key acquisition, without checking uniqueness of device keys. The content protection system includes a key data generation apparatus and a user terminal. The key data generation apparatus converts first key data, which is for using content, based on a predetermined conversion rule, thereby generating second key data, encrypts the second key data using a device key held by valid terminals, and outputs the encrypted key data. The user terminal obtains the encrypted key data, decrypts the encrypted key data using a device key held by the user terminal, thereby generating second key data, converts the second key data based on a re-conversion rule corresponding to the conversion rule, thereby generating the first key data, and uses the content with use of the generated first key data.