Digital data recording apparatus and a method for protecting copyrights that facilitate reproduction of encrypted digital data recorded on recording media, and a computer-readable recording medium that records a program of the method

A digital data recording apparatus for recording digital data on a recording medium, comprises: communication means (100) for receiving encrypted digital data via a digital network; decryption means (105) for decrypting the encrypted digital data that has been received by the communication means; encryption means (110) including a plurality of encryption units (111,112,113) that re-encrypt digital data that has been decrypted by the decryption means in encryption systems having different security levels; recording means (115) for recording digital data that has been re-encrypted by the encryption means on the recording medium; designation reception means (117) for receiving, from a user, an instruction regarding designation of one of the plurality of encryption units, the designation encryption unit being for re-encrypting the digital data that has been decrypted by the decryption means; and a controller (109) for controlling the decryption means, the encryption means and the designation reception means, characterised in that the controller has the designated encryption unit re-encrypt the digital data that has been decrypted by the decryption means.