
Tiered Access for Servers and Storage—Local and Remote 259
Storage and I/O interconnects have also evolved from various propri-
etary interfaces and protocols to industry-standard Fibre Channel, Infini-
Band, Serial Attached SCSI (SAS), and Serial ATA (SATA), as well as
Ethernet-based storage. With the exception of IBM legacy mainframes that
utilize count key data (CKD) or extended count key data (ECKD) formats
and protocols, open system computers, networking, and storage devices
have standardized on the SCSI command set for block I/O. Parallel SCSI
cabling still exists but is giving way to SAS, SATA, Fibre Channel, iSCSI,
and NAS solutions. The SCSI ...