Linphone

Mobile phone networks have Internet telephony as a direct competitor, since there are applications that offer a cost-effective alternative to keep in touch with others. Linphone is one of the software solutions in this category, relying on the Voice over IP (VoIP) protocol to allow free communication between users.

Linphone is compatible with SIP signaling protocols, as well as UDP, TCP and TLS. It can use IPv6 or IPv4 and connect to the Internet directly or from behind a firewall, in order to ensure data transfer security.

Aside from voice calls, it supports text messages and video calling, provided your computer is equipped with a compatible video capturing device, such as a webcam.

As for the usage, the configuration procedure shouldn't pose difficulties. You must specify the protocol to use and the media encryption method and enter the required information regarding your SIP account (identity, proxy address, username and nick).

The application remembers the call history and comes with a built-in keypad and an address book that can store all your SIP contacts.

Linphone allows you to customize the call notification sound file and adjust the resolution during video calls (it supports SVGA, CIF, QCIF, QVGA and more). It bundles a collection of predefined multimedia codecs that allow flawless video and audio transmissions.

It features bandwidth control, which means that you can set a limit to the download and the upload speed, but you can alternatively use the 'Adaptive Rate Control' option to leave this task to the application.

Providing support for simultaneous calls, Linphone is a reliable VoIP client that can connect to any SIP phone or account. It helps you make audio and voice calls to your loved ones, regardless of their location.