Install linphone-nogtk by entering the following commands in the terminal:
sudo apt update sudo apt install linphone-nogtk
Description:
SIP softphone - console-only client
Linphone is an audio and video internet phone using the SIP protocol. It has a GTK+ and console interface, includes a large variety of audio and video codecs, and provides IM features. . This package contains the console version of linphone.
Homepage: http://www.linphone.org/
Version: 3.6.1-3build1
Section: universe/sound