Thanks again.
Yes, you must be Kemper proprietary protocol. Your solution with the outer case seems very correct, even we can get power from KPA ethernet port.
Anyway, I will study the option of protocol on Ethernet.
I you connect your KPA in your home network, you can see this in your pc browser:
[Blocked Image: http://www.musiker-board.de/attachments/upload_2015-4-15_16-26-33-png.420095/]