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. 03, 2013
Filed:
Apr. 26, 2007
Toshihisa Nakano, Osaka, JP;
Masao Nonaka, Osaka, JP;
Yuichi Futa, Osaka, JP;
Motoji Ohmori, Osaka, JP;
Ryo Nojima, Tokyo, JP;
Kazukuni Kobara, Chiba, JP;
Hideki Imai, Kanagawa, JP;
Toshihisa Nakano, Osaka, JP;
Masao Nonaka, Osaka, JP;
Yuichi Futa, Osaka, JP;
Motoji Ohmori, Osaka, JP;
Ryo Nojima, Tokyo, JP;
Kazukuni Kobara, Chiba, JP;
Hideki Imai, Kanagawa, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A content distribution system for transferring contents between transmission device and reception device. The transmission device includes: key obtaining unit that obtains, from reception device, public keys and public key identifiers; watermark embedding unit that embeds a different public key identifier, as electronic watermark, into each of contents that are identical in substance; an encryption unit that encrypts contents using public keys to generate encrypted contents; and transmission unit that transmits encrypted contents to reception device. The reception device includes: key storage unit storing public keys, public key identifiers, and a private key that makes a pair with one of the public keys; key transmission unit that transmits public keys and public key identifiers to the transmission device; content receiving unit that receives encrypted contents from transmission device; and decryption unit that obtains a content from the received encrypted contents, using the private key.