Auto MDI/MDI-X
Summary
MDI switches, no idea what a good summary is here :shrug
MDI
Traditional MDI (Media dependant Interface) Switches send signals on pin 1 nd 2 and receive signals on 3 and 6.
MDI-X
MDI-X (Media Dependant Interface) Switches send signals on pin(s) 3 and 6, and receive signals on 3 and 6.
Auto MDI
Auto MDI detects the configuration on the network to ensure that sending and receiving signals happen on the correct pins.