10.0 Understanding RoCEv2
Visual deep dive into RoCEv2 — the protocol stack, every byte of every packet header, BTH opcodes, PFC backpressure, DCQCN congestion control, the CM handshake, and ECMP routing.
10.1 What RoCE v2 Is
RoCE v2 is not a new RDMA protocol — it's the InfiniBand transport wrapped in standard UDP / IP / Ethernet. The fabric this curriculum picks, used by Azure, Meta, Tencent, ByteDance, and most enterprise AI clusters.
10.2 PFC + ECN + DCQCN — the Lossless Trick
Why RoCE v2 leans on the PFC + ECN + DCQCN lossless stack you configured in Switch QoS — the RoCE-transport view of the three layers, the one tuning rule that decides line-rate vs PFC storm, and how to confirm RoCE v2 + DCQCN are actually on the wire.
10.3 How a RoCE v2 Transaction Actually Flows
End-to-end walk-through of one RoCE v2 transaction. What's borrowed from InfiniBand, what's borrowed from Ethernet, how a 1 MB RDMA WRITE gets chunked into 256 wire packets with sequential PSNs, how the receiver reassembles, how the IB transport guarantees ordering and reliability, and a tcpdump showing it on the wire.