> Wow, can anyone shed some light on how they time this? What sort of clock, I'm assuming its some fancy hardware that you use to benchmark at the 4 nano second level? Or do you just claim this and assume that no one can prove you wrong?

There are some expensive hardware solutions to capture all network traffic and timestamp it at nanosecond level. E.g.,

https://www.endace.com/endace-high-speed-network-recorders.h...