Cryptography – Key management – Key distribution
Reexamination Certificate
2011-05-10
2011-05-10
Truong, Thanhnga B (Department: 2438)
Cryptography
Key management
Key distribution
C380S277000, C380S279000, C380S280000, C380S281000, C380S282000, C380S283000, C380S284000, C380S285000, C380S286000, C380S044000, C380S045000, C380S046000, C380S047000, C380S200000, C380S201000, C380S202000, C380S203000, C713S170000, C713S171000, C713S172000, C705S050000, C705S057000, C705S071000
Reexamination Certificate
active
07940935
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 (204) reads a playback control information table (211) from a recording medium (102) via a reading unit (201). The key acquisition unit (204) acquires a rights key via a key acquisition intermediation unit (223) from an apparatus specified by an acquisition-destination type and a request-destination type that are stored in the playback control information table (211) and that corresponding to the content to be played. The key acquisition unit (204) generates a content key using the acquired rights key and, when required, a medium key recorded in a medium. A decryption unit (203) decrypts encrypted content using the content key.
REFERENCES:
patent: 6516064 (2003-02-01), Osawa et al.
patent: 6665303 (2003-12-01), Saito et al.
patent: 2002/0154779 (2002-10-01), Asano et al.
patent: 2003/0152222 (2003-08-01), Nakano et al.
patent: 2004/0039907 (2004-02-01), Sako et al.
patent: 2004/0073516 (2004-04-01), Yamamichi et al.
patent: 2004/0078584 (2004-04-01), Moroney et al.
patent: 2004/0093523 (2004-05-01), Matsuzaki et al.
patent: 0 756 279 (1997-01-01), None
patent: 11-194987 (1999-07-01), None
patent: 2000-113050 (2000-04-01), None
patent: 2003-037589 (2003-02-01), None
Kozuka Masayuki
Miyazaki Masaya
Nakahara Tohru
Okamoto Ryuichi
Tokuda Katsumi
Jeudy Josnel
Panasonic Corporation
Truong Thanhnga B
Wenderoth , Lind & Ponack, L.L.P.
LandOfFree
Content playback apparatus, content playback method,... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Content playback apparatus, content playback method,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Content playback apparatus, content playback method,... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2649067