We are an computer shop with an ISDN connection.
We have 3 USB VoiP phones and we want that they can call through the Server with our normal ISDN line.
normally you wouldn’t use the * box as a machine for USB phones. It would be much better to connect these phones into a PC each, and then make calls via a softphone on the PC.
If you wanted stand alone phones, you are most likey looking for SIP or IAX compatible hardware phones, such as a linksys SPA 922. These would be connected to the * box by ethernet.