Full duplex
From Hackepedia
Full duplex means 2 channels where each channel goes in the opposite direction of the other. What this means is that at 100 Mbps full duplex you can send 100 Mbps of data and receive 100 Mbps of data for an aggregate of 200 Mbps. Collisions in full duplex cannot happen. Ethernet switches are full-duplex most of the time.