Allied Telesis Support Portal

MDI/MDI-X Button on Media Converters

What is the function of the MDI/MDI-X Button on a media converter?

The MDI/MDI-X button allows you to change the MDI mode on the RJ-45 twisted pair port of the media converter. The RJ-45 twisted pair port on a PC, router, or bridge is typically wired as MDI, while the RJ-45 twisted pair port on a switch or hub is usually MDI-X.

MDI – Use the MDI setting if the RJ-45 twisted pair port of the media converter is connected to a switch or hub.

MDI-X – Use the MDI-X setting if the RJ-45 twisted pair port of the media converter is connected to a PC, router, or bridge.