Direct Access Storage Devices (FBA DASDs) to its line of CKD DASD. CKD DASD supported multiple variable-length sectors, while the IBM FBA DASD supported sector sizes of 512, 1024, 2048, or 4096 bytes.

In 2000, the industry trade organization, International Disk Drive Equipment and Materials Association (IDEMA) started work to define the implementation and standards that would govern sector size formats exceeding