In the iSCSI process, SCSI data is packaged into IP packets and transported over IP networks. This allows iSCSI to operate on existing Ethernetcabling and also over wide area networks. During communication, the packaged SCSI commands are sent to a SCSI router, which selects the appropriate target system based on existing mapping tables. The entire iSCSI data frame is composed of an Ethernet header followed by IP headers and TCP headers, the iSCSI header followed by the SCSI data.
On the computer side, an iSCSI card can support the protocol; on the storage side, a dedicated server is needed to interface with the network and is called an iSCSI router. iSCSI is used to provide external branch offices with access to the storage network via a virtual end-to-end connection without the need to set up dedicated storage devices in the branch offices.
The iSCSI process was developed by Cisco and IBM, among others, supported by many other companies and standardized by the Internet Engineering Task Force( IETF).