Patent ID: 7353543
Filing Date: 2008-04-01
Classification: G06F,G11B,H04N

Abstract:
1. A contents distribution system, wherein in circulation are first main content and a plurality of second main content, the first main content being held legitimately by a portable first recording medium, and each of the second main content being held legitimately by a different one of a plurality of second recording media, the first recording medium storing the first main content, a decryption key for sub-content pertaining to the first recording medium, an encryption key for sub-content pertaining to the first recording medium, and a plurality of encryption keys for sub-content pertaining to the plurality of second recording media, and each of the second recording media storing a second corresponding main content and a decryption key for sub-content pertaining to the corresponding second recording medium, the contents distribution system comprising: a contents supply apparatus; a contents acquisition apparatus; and a contents playback apparatus, wherein the contents supply apparatus comprises: the contents acquisition apparatus comprises: the contents playback apparatus, adapted to have mounted therein the first recording medium or one of the plurality of second recording media, comprises: