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:
Oct. 08, 2013
Filed:
May. 10, 2010
Kazuhiro Nomura, Osaka, JP;
Katsuhisa Yamaguchi, Osaka, JP;
Kazuhiro Nomura, Osaka, JP;
Katsuhisa Yamaguchi, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
Provided is a content transmission devicethat can reduce failure of content key confirmation processing during special playback such as fast-forwarding and fast-rewinding. A key management unitgenerates or updates a key parameter, and stores therein the generated or updated key parameter. The key management unitreceives a key parameter from the content reception device, and calculates a difference between the key parameter stored therein and the received key parameter. By using the calculated difference, a transmission control unitjudges whether or not to change a transmission speed at which an encrypted content portion is to be transmitted, and depending on a result of the judgment, selects one of transmission speeds and transmits the encrypted content portion in accordance with the selected transmission speed. When the difference is greater than a first threshold value, the transmission control unitselects one of the transmission speeds that is slower than a current transmission speed.