SCSI

Small Computer System Interface (SCSI) is a disk interfacing technology which provides specifications for connecting and transferring data to computers.  Since standardization in 1986, SCSI implementations were prevalent in Apple computers and servers.  Until recently, servers primarily shipped with SCSI drives however SAS drives are now building market share.

SCSI has evolved over the years which has caused changes in the connectors, power termination and now.  This makes forensic acquisition of SCSI drives slightly more complicated than (E)IDE or (S)ATA drives.  However, with the proper cables, adapters and knowledge, imaging SCSI drives is not difficult.

The evolution of SCSI is as follows:

• SCSI-1, 5MB/s
• Fast SCSI, 10MB/s
• Fast Wide SCSI, 20MB/s
• Ultra SCSI, 20MB/s
• Wide Ultra SCSI, 40MB/s
• Ultra2 SCSI, 40MB/s
• Wide Ultra2 SCSI, 80MB/s
• Ultra3 SCSI or Ultra160 SCSI 160MB/s
• Ultra320 SCSI, 320MB/s
• Ultra640 SCSI, 640MB/s