What do the terms RDMA, iWarp and RNIC refer to?
A. RDMA is a relatively new advanced technology which allows the Gigabit controller to use DMA to move Ethernet messages directly to and from application buffers thus relieving the current methods of copying data across the socket API interface. iWarp is a technology that uses RDMA in conjunction with TCP/IP data path offload to offload the CPU for TCP/IP data transfer while keeping the host protocol stack intact. This is in contrast to the current TOE technology which implements a separate TCP/IP stack residing on the TOE controller. RDMA and iWarp show great promise, especially for 10-Gigabit Ethernet where it is mostly needed, but to be successful it must gain the support of not only hardware vendors, but also the Internet protocol community and major operating system vendors. Another issue facing iWarp/RDMA is that applications have to be recoded to use a new API and there are additional protocol stack layers on top of TCP/UDP/IP required to support it. RDMA and iWarp is expected t
