FIELD: information technologies.
SUBSTANCE: medium comprises an area in a data area, which stores a unit of substitution to substitute a faulty unit arranged in a data area, and a list of defects. A record in the list of defects has the first index, indicating physical location of a faulty unit, and the second index, indicating physical location of a substitution unit corresponding to a faulty unit, and information on a status of a faulty unit and a substitution unit. The information on the status contains information that indicates whether a faulty unit is a single or a serial one. If a faulty unit is a serial one, then the second information is contained, indicating, whether a faulty unit is an initial unit or a final unit among serial faulty units. Also the medium additionally comprises a disc definition structure (DDS).
EFFECT: higher efficiency of medium space control.
12 dwg
