The installation is only slightly different from the one in DE.
Depending on the telecommunication system you have to install a TAPI driver (see for example with Ansitel-Cloud system).
So it is with Swisscom - the IP/Cloud - telephony connection must first of all support ECSTA/TAPI from the Swisscom side and then be configured accordingly.
A customer has to do this SELF. Without access data for ECSTA and a suitable connection the setup is not possible.
Installation of "SOTA" for CH customers-summary:
2. after successful installation of the ECSTA-TAPI driver the tab "TAPI" should appear in SOTA ( restart may be necessary ).
In the tab "TAPI" of the "SOTA" --> check "USE TAPI" and select the corresponding phone number interface. 4.
Save.