I have a potential application where the vast majority of the traffic will be in one direction, and, concurrently, I have a potential alternate use for a pair of wires in the cable that would facilitate this. So, it's got me wondering if any network equipment will negotiate gigabit in one direction and 100mb in the other direction. The idea is that one direction will have 2 pairs and the other direction will only have 1. I assume that this is impossible because the timing of handshakes (and whatever else goes on in the ethernet protocol) will be completely stirred. I'm not sure whether to call this partial duplex or mismatched duplex or.... Any thoughts?