With vSphere 6.5, we introduced RDMA over Converged Ethernet (RoCE). RDMA over Converged Ethernet (RoCE) is a network protocol that allows remote direct memory access (RDMA) over an Ethernet network. RoCE dramatically accelerates communication between two network endpoints leveraging DMA over converged Ethernet infrastructure.
For more information, please refer to vSphere documentation.
RoCE is supported in two modes RoCE v1 and RoCE v2.
The RoCE v1 protocol is an Ethernet link layer protocol with Ethertype 0x8915, it means that the frame length limits of the Ethernet protocol apply – 1500 bytes for a regular Ethernet frame and 9000 bytes for a jumbo frame.
The RoCEv2 protocol exists on top of either the UDP/IPv4 or the UDP/IPv6 protocol. The UDP destination port number 4791 has been reserved for RoCE v2. Since RoCEv2 packets are routable the RoCE v2 protocol is sometimes called Routable RoCE or RRoCE.
Following diagram shows the packet format for RoCEv1 and v2 protocols.
Today VMware is pleased to announce the RoCE (RDMA over Converged Ethernet) certification suite for vSphere 6.5. vSphere 6.5 certification suite allow Ethernet adapter vendor to certify their drivers and controllers in RoCE mode.
For detailed certification information, please refer here.