Patent ID: 8726030

Claim:
A terminal device recording content onto a recording medium device, a permission to record the content onto the recording medium device being granted by a server device, the terminal device comprising: a generation unit calculating a hash value for each of a plurality of subject content pieces of subject content using content subject to recording and a title key, and generating signature target data that includes the hash values calculated for the plurality of subject content pieces, a position of each subject content piece within the content subject to recording, and a size of each subject content piece; an information transmission unit requesting a permission from the server device to record the subject content onto the recording medium device by transmitting the signature target data generated by the generation unit to the server device; a signature reception unit receiving subject content signature data from the server device, the subject content signature data being transmitted by the server device upon granting the permission to record the subject content onto the recording medium device; and a recording unit recording the subject content onto the recording medium device as one of plain-text data and encrypted data, as well as the subject content signature data received by the signature reception unit.