iSCSI vs. SCSI
SCSI is a layer 2 deterministic channel protocol. It’s initials stand for “Small Computer Systems Interface.” It is a standard protocol for computer systems to connect to storage systems. SCSI protocol runs on Fibre Channel (called fibre channel protocol or FCP), Infiniband, and layer 2 Ethernet.
ANSI, SNIA, and the IEEE working groups mapped the SCSI protocol to TCP/IP to enable the SCSI protocol to work on layer 3 TCP/IP Ethernet. This standard is called iSCSI.
iSCSI is the SCSI protocol mapped to TCP/IP and run over standard Ethernet technologies.