Patent ID: 7663992

Claim:
A multi-layered information recording medium including a plurality of recording layers, wherein the multi-layered information recording medium is configured in a manner such that information can be optically recorded from one side of the multi-layered information recording medium into each of the plurality of recording layers, the multi-layered information recording medium comprising: a user data area for recording user data; a plurality of spare areas including at least one replacement region, wherein when the user data area includes at least one defect region, the at least one replacement region may be used in place of the at least one defect region; the user data area includes plurality of sectors, wherein a logical address is assigned to each of the plurality of sectors; and a plurality of defect management areas including a plurality of disc definition structures which include information about defect management of the user data area, wherein the plurality of recording layers include a first recording layer and a second recording layer positioned contiguous to each other, the first recording layer includes a first spare area, a first user data area and a second spare area along a track path direction, the second recording layer includes a third spare area, a second user data area and a fourth spare area along a track path direction, the second spare area and the third spare area are positioned approximately at the same radial position on the multi-layered information recording medium, the disc definition structure includes a plurality of spare area full flags respectively assigned to the first to fourth spare areas, each of which represents whether there is an available replacement region in the corresponding spare area, and the plurality of spare area full flags are disposed in ascending order of logical addresses of flanking sectors of the respective spare areas.