Remote Direct Memory Access (RDMA) is a concept whereby two or more computers communicate via Direct Memory Access directly from the main memory of one system to the main memory of another. As there is no CPU, cache, or context switching overhead, this is particularly useful in applications where high thoughput, low latency networking is needed such as in massively parallel Linux clusters. The most common RDMA implementation is over Infiniband. Although RDMA over Infiniband is technologically superior to most alternatives, it faces an uncertain commercial future.