Patent ID: 7702109

Claim:
A content recording/reproducing system that includes a distribution device, a first recording medium, a second recording medium, a recording device that records a sub-content relating to a main content and a reproducing device, that reproduces the sub-content relating to the main content, the distribution device comprising: a verification information generation unit operable to, based on a secret key, apply a digital signature to relative information relating to the sub-content, and generate verification information including the sub-content; and an output unit operable to output to the recording device the verification information, the first recording medium comprising a non-rewritable area where the main content and key data that is used for acquiring a public key corresponding to the secret key are prestored, an authorized reproducing device being able to acquire the public key using the key data, the second recording medium comprising a rewritable area, the recording device comprising: a receiving unit operable to receive from the distribution device the verification information; and a recording unit operable to record the verification information on the second recording medium when the second recording medium is installed to the recording device, and the reproducing device comprising: an acquiring unit operable to (i) acquire the key data from the first recording medium when the first recording medium is installed to the reproducing device and (ii) acquire the verification information including the sub-content from the second recording medium when the second recording medium on which the verification information is recorded is installed to the reproducing device; and a reproducing unit operable to acquire the public key corresponding to the secret key based on the key data, verify the verification information with the public key, and reproduce the sub-content included in the verification information in conjunction with reproduction of the main content when the verification information is verified.