Patent ID: 7031472
Filing Date: 2006-04-18
Classification: G11B

Abstract:
1. A method of authenticating a recording medium and a disk playback apparatus, comprising the steps of performing an absolute authentication process for authenticating a recording medium with information for authentication being recorded in a predetermined position therein, according to a first rule at a predetermined time, wherein said first rule is that normal authentication is declared in said absolute authentication process if the information for authentication is detected as being recorded in said predetermined position; executing a program transferred from said recording medium if normal authentication is declared in said absolute authenticating process; and performing an arbitrary authentication process for authenticating a disk playback apparatus according to a second rule at an arbitrary time while executing said program, wherein said second rule is that normal authentication is declared in said arbitrary authentication process if the information for authentication is not detected in arbitrary positions other than said predetermined position, wherein said absolute authentication process is performed when said recording medium starts being accessed for the first time, and said arbitrary authentication process is performed at least once after said absolute authentication process.