If you take a look on the Appmodule, you will find different Ports which are necessary for the uses.
The Appmodule KNX features the following ports:
.) KNX Port for wired connection to the KNX system > KNX -, KNX +
.) Connecter for ethernet LAN > RJ-45
.) Connecting terminal for voltage supply > 12-24 VDC
The Appmodule IP features the following ports:
.) Connecter for ethernet LAN > RJ-45
.) Connecting terminal for voltage supply > 12-24 VDC
The APPMODULE and the ekey devices are communicating over IP inside the same network.