What is iSCSI?
• A storage protocol that enables block I/O data
transfers over standard IP networks
• Encapsulates block-level serial SCSI-3
commands and data in a TCP/IP frame
• Designed to allow hosts to directly access
storage over an IP infrastructure
• Joint development project of IETF and ANSI T10
committee
IP
TCP
iSCSI
SCSI
Data
The internet Small Computer Systems Interface (iSCSI) protocol defines the
rules and processes to transmit and receive block storage applications over
TCP/IP networks.
iSCSI enables SCSI-3 commands to be encapsulated in TCP/IP packets and
delivered reliably over IP networks.
• we take our data, the same as we did before, the data goes inside SCSI.
• Our SCSI headers then get wrapped up inside an iSCSI header.
o That iSCSI header is the equivalent of our Fibre Channel headers.
But an iSCSI header is 48 bytes long.
• The iSCSI frame then goes inside TCP which gives us guaranteed in
order delivery, which will then go inside IP.
• IP gives us our logical routable address.