"Traditionally, Lustre is configured to manage remote data
storage disk devices within a Storage Area Network (SAN), which is
two or more remotely attached disk devices communicating via a
Small Computer System Interface (SCSI) protocol. This includes
Fibre Channel, Fibre Channel over Ethernet (FCoE), Serial Attached
SCSI (SAS) and even iSCSI. To better explain what a SAN is, it may
be more beneficial to begin with what it isn't. For instance, a SAN
shouldn't be confused with a Local Area Network (LAN), even if that
LAN carries storage traffic (that is, via networked filesystem
shares and so on). Only if the LAN carries storage traffic using
the iSCSI or FCoE protocols can it then be considered a SAN.
Another thing that a SAN isn't is Network Attached Storage
(NAS). Again, the SAN relies heavily on a SCSI protocol, while the
NAS uses the NFS and SMB/CIFS file-sharing protocols.