iSCSI Extensions for RDMA

The iSCSI Extensions for RDMA (iSER) is a computer network protocol that extends the Internet Small Computer System Interface (iSCSI) protocol to use Remote Direct Memory Access (RDMA).

RDMA can be provided by:

• Transmission Control Protocol (TCP) with RDMA services (iWARP), which uses an existing Ethernet setup and therefore has lower hardware costs.
• RoCE (RDMA over Converged Ethernet), which does not need the TCP layer and therefore provides lower latency.
• InfiniBand

iSER permits data to be transferred directly into and out of SCSI computer memory buffers (those which connect computers and storage devices) without intermediate data copies and with minimal CPU involvement.