Method and apparatus for preventing data copying from a disk using data lengths too large for a pirate medium

A data recording apparatus for recording data on a disk shaped recording medium comprising:

• recording data making means for making recording data which satisfies a relationship expressed as M.gtoreq.W.gtoreq.D where
• M is the maximum recordable data length defined by the standard of a first disk shaped recording medium,
• W is the data length of recording data which is to be recorded on the first disk shaped recording medium, and
• D is the data length of effective data which is effective on access;
• and
• recording means for recording the recording data made by the recording data making means on the first disk shaped recording medium,
• wherein the data making means makes the recording data have a relationship of W>m where m is a maximum recordable data length of a second data recordable disk shaped recording medium associated with the first disk shaped recording medium.

A disk shaped recording medium, wherein recording data which satisfies a relationship expressed as M.gtoreq.W.gtoreq.D is recorded where

• M is the maximum recordable data length defined by the standard of the disk shaped recording medium,
• W is the data length of recording data which is to be recorded on the disk shaped recording medium, and
• D is the data length of effective data which is effective on access,
• wherein the recording data satisfies a relationship of W>m, wherein m is a maximum recordable data length of a different data recordable disk shaped recording medium which is associated with the disk shaped recording medium.

A computer system including a first storage device for reproducing information data from a first disk shaped recording medium, a second storage device for recording information data on a second disk shaped recording medium and control apparatus for controlling the first and second storage devices, the computer system comprising:

• data length detection means for detecting a data length W of information data recorded on the first disk shaped recording medium;
• detection means for detecting whether the data length W is longer than a maximum recordable data length m determined by standards for the second disk shaped recording medium;
• and
• copy restricting means for restricting information data recorded on the first disk shaped recording medium from being copied to the second disk shaped recording medium when the detection means determines W>m.