BACKGROUND

The transmission control protocol (TCP) network protocol may use many different network congestion control schemes. Data Center TCP (DCTCP) is a TCP congestion control scheme for data-center traffic, and is described in RFC 8257 published by the Internet Engineering Task Force (IETF). DCTCP scales the TCP congestion window based on an estimate of the number of transferred bytes that encounter congestion.

Remote direct memory access (RDMA) network protocols allow direct access to the memory of a remote computing device without involving the remote operating system. RDMA over converged Ethernet (RoCE) is a network protocol published by the InfiniBand℠ Trade Association that allows RDMA over an Ethernet network. RoCE version one (RoCEv1) is an Ethernet link layer protocol. RoCE version two (RoCEv2) is an Internet layer protocol that is routable between networks. The RoCEv2 specification defines a congestion control protocol based on RFC 3168 published by the IETF. As part of the RoCEv2 congestion control protocol, a receiver sends one or more congestion notification packets (CNPs) to the transmitter device.

