Old New Criteria
Desktop/Laptop ATA � SATA Cost
Workstation SCSI � SAS Performance
Enterprise Storage SCSI � FC Performance
Note that all modern interfaces are now SERIAL interfaces
We use more silicon, but use less cable and connector pins
If we look at the original design criteria for drive interfaces.
Early desktop systems were price sensitive so the design criteria was for a low
cost solution. The approach was to develop a command set that used the host
processor to control the functions, and integrate only the electronics on the
As things evolved we wanted a higher performance drive, so SCSI developed
a solution where all instructions are implemented in hardware, a controller.
This has the benefit of higher performance, deterministic latency and does not
rely on the host processor.