Patent ID: 6694023
Filing Date: 2004-02-17
Classification: G11B,H04N

Abstract:
A copyright protection method to protect a copyright with respect to information to be recorded on a digital recording medium, the copyright protection method comprising:encrypting the information to be recorded on the digital recording medium using a cryptosystem of a plurality of cryptosystems; recording the information encrypted on the digital recording medium; and recording a cypher key to differentiate the cryptosystem, among the plurality of cryptosystems, as the cryptosystem used to encrypt the encrypted information, such that the encrypted information can be decrypted by using the cryptosystem, not stored on the digital recording medium, after identification by the cypher key, with the cypher key being recorded so that the cypher key is not allowed to be copied, wherein said digital recording medium is an optical disk and said cypher key is recorded on a burst cutting area (BCA) of the optical disk.