Flow-control as in ECN or Ethernet/pause? Loss is inevitable in most cloud network fabrics due to the use of shallow buffer commodity ASICs, the amount of fan-

Flow-control as in ECN or Ethernet/pause? Loss is inevitable in most cloud network fabrics due to the use of shallow buffer commodity ASICs, the amount of fan-in, and the reliance on tenants to use the network in a typical manner (don't fragment, don't encap, preserve entropy). RDMA is going to be tough - microseconds count, you can't wait for TCP to retrans, and UDP doesn't provide the reliability needed. A new transport protocol is likely the answer.