When discussing this issue, we need to clarify one thing first: We know that in early SAN storage systems, data transmission between servers and switches was carried out via fiber optics. This is because the server transmits SCSI commands to the storage device, which cannot use the standard IP protocol of a regular LAN network; therefore, FC (Fiber Channel) transmission is required. As a result, this type of SAN is called FC-SAN. Later on, SANs emerged that used IP protocol encapsulation, allowing them to fully operate over standard LAN networks, and thus they are called IP-SAN. The most typical example of this is the currently popular iSCSI.