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US 7,353,543 B2Granted
Contents distribution system
AssigneeMatsushita Electric Industrial Co., Ltd.
InventorsMotoji Ohmori, Masataka Minami, Masaya Yamamoto
Life of this patent
Estimating the term…
Abstract
A contents supply apparatus supplies sub-content that relates to main content. A DVD-ROM stores a bind key unique to the DVD-ROM and main content that is a digital work. A main player reads the bind key from the DVD-ROM, acquires sub-content that relates to the main content stored on the DVD-ROM, generates encrypted sub-content by encrypting the acquired sub-content based on the read bind key, and writes the generated encrypted content to an SD memory card. A sub-player reads the bind key from the DVD-ROM, reads the encrypted sub-content from the SD memory card, generates sub-content by decrypting the read encrypted sub-content based on the bind key, and plays back the generated sub-content.
Claims9
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:
- a storage unit operable to store sub-content and a sub-content key for the sub-content;
- an encryption unit operable to encrypt the sub-content with use of the sub-content key to generate encrypted sub-content;
- and
- a transmission unit operable to transmit the sub-content key and the encrypted sub-content,
- the contents acquisition apparatus comprises:
- a reception unit operable to receive the sub-content key and the encrypted sub-content;
- a reading unit operable to read, from the first recording medium, the encryption key for sub-content pertaining to the first recording medium, and the plurality of encryption keys for sub-content pertaining to the plurality of second recording media;
- an encryption unit operable to repeatedly encrypt the received sub-content key with use of the read plurality of encryption keys for sub-content, to generate an encrypted sub-content key with each of the encrypted keys, thereby generating a plurality of encrypted sub-content keys;
- and
- a writing unit operable to write the received encrypted sub-content and the plurality of generated encrypted sub-content keys to a portable memory card, and
- the contents playback apparatus, adapted to have mounted therein the first recording medium or one of the plurality of second recording media, comprises:
- a first reading unit operable to read the decryption key for sub-content pertaining to the first recording medium from the first recording medium, or read the decryption key for sub-content pertaining to the second recording medium from the second recording medium;
- a second reading unit operable to read, from the memory card, the encrypted sub-content and from among the encrypted sub-content keys stored in the memory card, one of the plurality of encrypted sub-content keys that corresponds to the mounted recording medium;
- a first decryption unit operable to decrypt, with use of the read decryption key, the encrypted sub-content key read from the memory card, to generate a decrypted sub-content key;
- a second decryption unit operable to decrypt, with use of the generated decrypted sub-content key, the encrypted sub-content read from the memory card, to generate decrypted sub-content;
- and
- a playback unit operable to play back the generated decrypted sub-content.
23 more elements
A contents acquisition apparatus for acquiring sub-content from a contents supply apparatus, 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 acquisition apparatus comprising:
- a reception unit operable to receive, from the contents supply apparatus, a sub-content key and encrypted sub-content that has been generated by encrypting the sub-content with use of the sub-content key;
- a reading unit operable to read, from the first recording medium, the encryption key for sub-content pertaining to the first recording medium, and the plurality of encryption keys for sub-content pertaining to the plurality of second recording media;
- an encryption unit operable to repeatedly encrypt the received sub-content key with use of the read plurality of encryption keys for sub-content, to generate an encrypted sub-content key with each of the encryption keys, thereby generating a plurality of encrypted sub-content keys;
- and
- a writing unit operable to write the received encrypted sub-content and the generated plurality of encrypted sub-content keys to a portable memory card.
6 more elements
A contents playback apparatus for playing back sub-content recorded on a memory card, 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 playback apparatus, adapted to have mounted therein the first recording medium or one of the second recording media, comprising:
- a first reading unit operable to read the decryption key for sub-content pertaining to the first recording medium from the first recording medium, or read the decryption key for sub-content pertaining to the second recording medium from the second recording medium;
- a second reading unit operable to read, from the memory card storing encrypted sub-content and a plurality of encrypted sub-content keys, the encrypted sub-content and from among the encrypted sub-content keys stored in the memory card, one of the plurality of encrypted sub-content keys corresponding to the mounted recording medium;
- a first decryption unit operable to decrypt, with use of the read decryption key, the encrypted sub-content key read from the memory card, to generate a decrypted sub-content key;
- a second decryption unit operable to decrypt, with use of the generated decrypted sub-content key, the encrypted sub-content read from the memory card, to generate decrypted sub-content;
- and
- a playback unit operable to play back the generated decrypted sub-content.
7 more elements
A contents acquisition method used in a contents acquisition apparatus for acquiring sub-content from a contents supply apparatus, 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 acquisition method comprising:
- a reception step of receiving, from the contents supply apparatus, a sub-content key and encrypted sub-content that has been generated by encrypting the sub-content with use of the sub-content key;
- a reading step of reading, from the first recording medium, the encryption key for sub-content pertaining to the first recording medium, and the plurality of encryption keys for sub-content pertaining to the plurality of second recording media;
- an encryption step of repeatedly encrypting the received sub-content key with use of the read plurality of encryption keys for sub-content, to generate an encrypted sub-content key with each of the encryption keys, thereby generating a plurality encrypted sub-content keys;
- and
- a writing step of writing the received encrypted sub-content and the generated plurality of encrypted sub-content keys to a portable memory card.
6 more elements
A contents acquisition program recorded on a computer-readable recording medium and used in a contents acquisition apparatus for acquiring sub-content from a contents supply apparatus, 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 acquisition program comprising:
- a reception step of receiving, from the contents supply apparatus, a sub-content key and encrypted sub-content that has been generated by encrypting the sub-content with use of the sub-content key;
- a reading step of reading, from the first recording medium, the encryption key for sub-content pertaining to the first recording medium, and the plurality of encryption keys for sub-content pertaining to the plurality of second recording media;
- an encryption step of repeatedly encrypting the received sub-content key with use of the read plurality of encryption keys for sub-content, to generate an encrypted sub-content key with each of the encryption keys, thereby generating a plurality encrypted sub-content keys;
- and
- a writing step of writing the received encrypted sub-content and the generated plurality of encrypted sub-content keys to a portable memory card.
6 more elements
A contents playback method used in a contents playback apparatus for playing back sub-content recorded on a memory card, 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 playback method comprising:
- a first reading step of reading the decryption key for sub-content pertaining to the first recording medium from the first recording medium, or reading the decryption key for sub-content pertaining to the second recording medium from the second recording medium;
- a second reading step of reading, from the memory card storing encrypted sub-content and a plurality of encrypted sub-content keys, the encrypted sub-content and from among the encrypted sub-content keys stored in the memory card, one of the plurality of encrypted sub-content keys corresponding to the mounted recording medium;
- a first decryption step of decrypting, with use of the read decryption key, the encrypted sub-content key read from the memory card, to generate a decrypted sub-content key;
- a second decryption step of decrypting, with use of the generated decrypted sub-content key, the encrypted sub-content read from the memory card, to generate decrypted sub-content;
- and
- a playback step of playing back the generated decrypted sub-content.
7 more elements
A contents playback program recording on a computer-readable recording medium and used in a contents playback apparatus for playing back sub-content recorded on a memory card, 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 playback program comprising:
- a first reading step of reading the decryption key for sub-content pertaining to the first recording medium from the first recording medium, or reading the decryption key for sub-content pertaining to the second recording medium from the second recording medium;
- a second reading step of reading, from the memory card storing encrypted sub-content and a plurality of encrypted sub-content keys, the encrypted sub-content and from among the encrypted sub-content keys stored in the memory card, one of the plurality of encrypted sub-content keys corresponding to the mounted recording medium;
- a first decryption step of decrypting, with use of the read decryption key, the encrypted sub-content key read from the memory card, to generate a decrypted sub-content key;
- a second decryption step of decrypting, with use of the generated decrypted sub-content key, the encrypted sub-content read from the memory card, to generate decrypted sub-content;
- and
- a playback step of playing back the generated decrypted sub-content.
7 more elements
Dependencies are inferred from the claim text.