Patent ID: 8250442

Claim:
An information recording medium for recording and reproducing data thereon on a sector-by-sector basis, comprising ECC blocks as units for performing an error correction process, each ECC block comprising a plurality of sectors, wherein at least one sector having data recorded therein is managed as an extent, and at least one extent is managed as a file, at least one file being managed by using a file structure, wherein the file structure comprises unused space management information for identifying a used region and an unused region, and wherein, in a case where data which is not large enough to fill one of the ECC blocks, a padding extent is recorded in the unused area of the ECC block, the padding extent is an extent which is already allocated and is showing to be an unused area, wherein a defect ECC block which is detected as to include a defect sector within recording of a real time data is skipped, the skipped defect ECC block is registered as an unused area in the unused space management information, the position information of the skipped defect ECC block is stored in a defect list, the real time data as to be recorded before in the skipped defect ECC block is recorded in the ECC block which is recordable next after the skipped defect ECC block, and wherein the defect sector is an area which cannot be reproduced for a suitable data which is already recorded on the information recording medium, and the extent can include one or more skipped ECC blocks.