Patent ID: 8006308

Claim:
A non-transitory computer readable medium having a first data field area for storing copy protection information, comprising: a data area for storing main data; and a lead-in area for storing copy protection indicating information indicating if the computer readable medium contains the copy protection information in the first data field area or if the computer readable medium does not contain the copy protection information in the first data field area, the copy protection information being encryption/decryption key information required for use in encrypting/decrypting the main data, the copy protection indicating information being included within a control information unit including at least medium size information, medium structure information, and data zone allocation information, the control information unit being repeatedly recorded in a second data field area in the lead-in area of the computer readable medium, the copy protection indicating information and the copy protection information being recorded in a wobbled pattern by a bi-phased modulation method, the first data field area being separated from the second data field area, and the copy protection information being present depending on the indication of the copy protection indicating information.