CAD Ground Control connection

Hello everyone
Does anyone have experience /knowledge of the optimum connection of a K40 to CAD ground control.
I have spare ethernet and usb connections available, Which one would be best? Any ideas?

I use the USB out on my K50 to my CAD GC3. I was not aware that CAD had a GC cable to connect via RJ45.

This is an excerpt from a quote for using CAD products on my own system. The recommendations regarding exactly which products to use & how best to connect them to my system came directly from Scott Berry of CAD (GC3 for the K50).

Many thanks. Looks like one of the 4 usb ports is the way to go. The K40 doesnt have USB out.

The GC3 has just arrived, took a long time coming. Decided to go with RJ45 cables from my K40 and Phoenix Net. Found the USB cable to be a loose fit in the K40.