linphone software package provides SIP softphone - graphical client, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install linphone
linphone is installed in your system.
Make ensure the linphone package were installed using the commands given below,
$ sudo dpkg-query -l | grep linphone *
You will get with linphone package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Sound |
| Package | linphone |
| Version | 3.6.1-2.1build2 |
| Description | SIP softphone - graphical client |
| Sub Section | Sound |