D.1 SwyxWare as the main telecommunication system
In this case, an existing telecommunication system is operated as a sub-telecommunication system on SwyxWare, for example. SwyxWare manages the access to the public telephone network as well as to other networks. The sub-PBX is connected via ISDN to SwyxWare. The ISDN cards provided for this must be operated in NT mode in this case.