> Some kind of ethernet light where say: frames can be as short as few bytes... On that note: To keep overhead low for sensors, SatCat5 does not impose a minim

> Some kind of ethernet light where say: frames can be as short as few bytes... On that note: To keep overhead low for sensors, SatCat5 does not impose a minimum frame length on SPI or UART interfaces. i.e., The minimum payload length is zero bytes. You still have 18 bytes of overhead (destination, source, EtherType, FCS) per Ethernet frame, but that is still a huge win for the low-speed interfaces that need it most. For compatibility's sake, runt-frames are zero-padded (and FCS updated) before transmission on conventional Ethernet interfaces (*MII). But typically those are running at 100+ Mbps so the impact is acceptable.