SCSI Disk Controllers
SCSI controllers can be divided into five generic classes. Very old ones support only Asynchronous SCSI, old controllers support Synchronous SCSI, most recent ones support Fast Synchronous SCSI; the latest two types to appear are Fast and Wide Synchronous SCSI, and Ultra SCSI. In addition, there are now two kinds of fiber channel that carry the SCSI protocol. Working out which type you have on your Sun is not that simple. The main differences between interface types are in the number of disks that can be supported on a SCSI bus before the bus becomes saturated and the maximum effective cable length allowed.
SCSI Interface Types
The original asynchronous and synchronous SCSI interfaces support data rates up to 5 Mbytes/s ...