SCSI MODEL
SCSI STANDARDS
| Techology Name | Maximum Cable length [m] | Maximum Speed [MBps] | Maximum number of Devices |
| SCSI-1 | 6 Single Ended | 5 | 8 |
| Fast SCSI | 3 Single Ended | 10 | 8 |
| Fast Wide SCSI | 3 Single Ended | 20 | 16 |
| Ultra SCSI | 1.5 Single Ended | 20 | 8 |
| Ultra SCSI | 3 Single Ended | 20 | 4 |
| Wide Ultra SCSI | - | 40 | 16 |
| Wide Ultra SCSI | 1.5 Single Ended | 40 | 8 |
| Wide Ultra SCSI | 3 Single Ended | 40 | 4 |
| Ultra2 SCSI | 12 LVD / 25 HVD | 40 | 8 |
| Wide Ultra2 SCSI | 12 LVD / 25 HVD | 80 | 16 |
| Ultra3 SCSI | 12 LVD | 160 | 16 |
| Ultra320 SCSI | 12 LVD | 320 | 16 |
| Ultra640 SCSI | 10 LVD | 640 | 16 |