RoCEv2多播报文格式

RoCEv2 (RDMA over Converged Ethernet version 2) uses PFC (Priority Flow Control) and DCB (Data Center Bridging) protocols to enable lossless Ethernet and faster data transfer. RoCEv2 also supports multicast traffic, which allows a single sender to send data to multiple receivers in a network. The multicast traffic is identified by a specific multicast group address.

The format of RoCEv2 multicast packets is similar to unicast packets, with the following differences:

- The destination MAC address is set to the multicast group address.
- The Ethernet type field is set to 0x8915, which indicates a RoCE packet.
- The RoCE header includes a multicast flag, which is set to 1 to indicate that the packet is a multicast packet.
- The RoCE header also includes a multicast group ID, which identifies the multicast group to which the packet belongs.

Below is an example of the RoCEv2 multicast packet format:

+-------------------------+
| Ethernet II Header      |
+-------------------------+
| RoCEv2 Header           |
+-------------------------+
| Payload (RDMA Data)     |
+-------------------------+

Note that the specific format and fields of the RoCEv2 multicast packet may vary depending on the implementation and configuration of the network.