Hello sepson,
Here is the configuration needed to do VOIP with Swisscom.
1.- Activation of SIP Credentials in the customer area
2.- Receipt of parameters to be inserted in the fields marked in red
3.- Check the audio codecs (compatibility see RFC) that you use.
I have attached my config as an example because I don’t have Zyxel.
I also use this config with Linphone and Zoiper.
Good luck 🙂
Good evening Sepson, yes you have two solutions:
1.- your phone or the base of your phone (e.g. Gigaset GO-Box 100) is IP (SIP) compatible
2.- you have software on your smartphone (e.g. Linphone) or PC capable of initializing the SIP protocol.
In both cases you need the parameters referenced in my image.
Anywhere you access the Internet and the ports to initialize the SIP protocol are open, you call and receive messages as if you were at home 🙂
Good evening