iSCSI SAN Concepts
iSCSI SANs use Ethernet connections between computer systems, or host servers, and high performance storage subsystems. SAN components include iSCSI Host Bus Adapters (HBAs) or Network Interface Cards (NICs) in the host servers, switches, and routers that transport the storage traffic, cables, storage processors, and storage disk systems.
iSCSI SAN uses a client-server architecture. The client, called iSCSI initiator, operates on the host. It initiates iSCSI sessions by issuing iSCSI commands and transmits them, encapsulated using the iSCSI protocol, to a server. The server is known as the iSCSI target. The iSCSI target represents a physical storage system on the network. It can also be provided by a virtual iSCSI SAN, for example, an iSCSI target emulator running in a virtual machine. The iSCSI target responds to the initiator's commands by transmitting the required iSCSI data.