How is it even possible to have correctly functioning circuits at such high speeds? I'm guessing at the very bottom of the Phy layer there several transistors switching at incredibly fast speeds. I understand that these transistors have several parameters such as their delay, rise, and fall time. Things most certainly don't happen instantaneously, a few logic ICs I played with also have a propagation delay time specified in their data sheets lasting a few nanoseconds.
Take the deserializer for an example, happening at 16Gb/s, which if I understand correctly equates to 1 bit every 62.5ps (0.0625ns). How does any circuit affected by the parameters I just talked about handle signals at such high speeds?
(Please go easy on me, I know some of my assumptions are probably wrong or oversimplified but I would love to learn more)