What I would like to know is what the theoretical speed is. Is it a gigabit or a gibibit? And on what layer does it transport that ammount of data? That is, are the ethernet header, CRC and preamble (and anything I forgot) included in the 1 gigabit, or can you send 1 gigabit/s on top of them? So what is the theoretical maximum bytes/s over raw ethernet (so not even using IP) that could be send then?