You are assuming that a high performance, latency tuned system is using the OS network stack. This would be a petty naive implementation. Offerings from Solarfalre (OpenOnload) and Exablaze (ExaSock) transparently offload and bypass the kernel stack. Quoted performance numbers are around 1us, of which 500ns is spent getting up and down the PCIE bus. Offloading to the nic makes a whole lot of sense in this space except that it has already been done, and with more compelling perfomance. The authors compleltly failed to take into account existing work.