Yes, the DTH-P1 can be plugged on an ATCA node slot. To do so, 2 jumpers should be changed to "NODE"position (J26 at bottom front position on the card, J45 back middle position on card).
It is written on board "NODE"or HUB".

In this configuration, the ethernet connection can be done from the backplane (if you have a switch on the HUB1 slot)