__NOTOC__ Linphone (contraction of ''

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, whi ...

phone'') is a free

voice over IP Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms Internet t ...

softphone A softphone is a software program for making telephone calls over the Internet using a general purpose computer rather than dedicated hardware. The softphone can be installed on a piece of equipment such as a desktop, mobile device, or other comp ...

, SIP client and service. It may be used for audio and video direct

call Call or Calls may refer to: Arts, entertainment, and media Games * Call, a type of betting in poker * Call, in the game of contract bridge, a bid, pass, double, or redouble in the bidding stage Music and dance * Call (band), from Lahore, Paki ...

s and calls through any VoIP softswitch or

IP-PBX An IP PBX ("Internet Protocol private branch exchange") is a system that connects telephone extensions to the public switched telephone network (PSTN) and provides internal communication for a business. An IP PBX is a PBX system with IP connectiv ...

. Linphone also provides the possibility to exchange instant messages. It has a simple multilanguage interface based on Qt for

GUI The GUI ( "UI" by itself is still usually pronounced . or ), graphical user interface, is a form of user interface that allows users to interact with electronic devices through graphical icons and audio indicator such as primary notation, inste ...

and can also be run as a

console Console may refer to: Computing and video games * System console, a physical device to operate a computer ** Virtual console, a user interface for multiple computer consoles on one device ** Command-line interface, a method of interacting with ...

-mode application on Linux. The softphone is currently developed by Belledonne Communications in France. Linphone was initially developed for

but now supports many additional platforms including

Microsoft Windows Windows is a group of several proprietary graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for ...

macOS macOS (; previously OS X and originally Mac OS X) is a Unix operating system developed and marketed by Apple Inc. since 2001. It is the primary operating system for Apple's Mac computers. Within the market of desktop and la ...

, and mobile phones running

Windows Phone Windows Phone (WP) is a discontinued family of mobile operating systems developed by Microsoft for smartphones as the replacement successor to Windows Mobile and Zune. Windows Phone featured a new user interface derived from the Metro design lan ...

, iOS or Android. It supports

ZRTP ZRTP (composed of Z and Real-time Transport Protocol) is a cryptographic key-agreement protocol to negotiate the keys for encryption between two end points in a Voice over IP (VoIP) phone telephony call based on the Real-time Transport Protocol. ...

for

end-to-end encrypted End-to-end encryption (E2EE) is a system of communication where only the communicating users can read the messages. In principle, it prevents potential eavesdroppers – including telecom providers, Internet providers, malicious actors, and eve ...

voice and video communication. Linphone is licensed under the GNU GPL-3.0-or-later and supports

IPv6 Internet Protocol version 6 (IPv6) is the most recent version of the Internet Protocol (IP), the communications protocol that provides an identification and location system for computers on networks and routes traffic across the Internet. I ...

. Linphone can also be used behind network address translator (NAT), meaning it can run behind home routers. It is compatible with telephony by using an

Internet telephony service provider An Internet telephony service provider (ITSP) offers digital telecommunications services based on Voice over Internet Protocol (VoIP) that are provisioned via the Internet. ITSPs provide services to end-users directly or as whole-sale suppliers ...

(ITSP).

Features

Linphone hosts a free SIP service on its website. The Linphone client provides access to following functionalities: * Multi-account work * Registration on any SIP-service and line status management * Contact list with status of other users * Conference call initiation * Combination of message history and call details * DTMF signals sending (SIP INFO / RFC 2833) * File sharing * Additional plugins

Open standards support

Protocols

* SIP according to RFC 3261 ( UDP, TCP and

TLS TLS may refer to: Computing * Transport Layer Security, a cryptographic protocol for secure computer network communication * Thread level speculation, an optimisation on multiprocessor CPUs * Thread-local storage, a mechanism for allocating vari ...

) * SIP

SIMPLE Simple or SIMPLE may refer to: *Simplicity, the state or quality of being simple Arts and entertainment * ''Simple'' (album), by Andy Yorke, 2008, and its title track * "Simple" (Florida Georgia Line song), 2018 * "Simple", a song by Johnn ...

NAT traversal Network address translation traversal is a computer networking technique of establishing and maintaining Internet protocol connections across gateways that implement network address translation (NAT). NAT traversal techniques are required for m ...

by TURN and ICE * RTP/ RTCP * Media-security: SRTP and

Audio codecs

Audio codec support:

Speex Speex is an audio compression codec specifically tuned for the reproduction of human speech and also a free software speech codec that may be used on VoIP applications and podcasts. It is based on the CELP speech coding algorithm.Xiph.OrIntro ...

(narrow band and wideband), G.711 ( μ-law,

A-law An A-law algorithm is a standard companding algorithm, used in European 8-bit PCM digital communications systems to optimize, i.e. modify, the dynamic range of an analog signal for digitizing. It is one of two versions of the G.711 standar ...

GSM The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation ( 2G) digital cellular networks used by mobile devices such ...

Opus ''Opus'' (pl. ''opera'') is a Latin word meaning "work". Italian equivalents are ''opera'' (singular) and ''opere'' (pl.). Opus or OPUS may refer to: Arts and entertainment Music * Opus number, (abbr. Op.) specifying order of (usually) publicatio ...

, and

iLBC Internet Low Bitrate Codec (iLBC) is a royalty-free narrowband speech audio coding format and an open-source reference implementation (codec), developed by Global IP Solutions (GIPS) formerly Global IP Sound (acquired by Google Inc in 2011). ...

(through an optional plugin)

Video codecs

Video codec support:

MPEG-4 MPEG-4 is a group of international standards for the compression of digital audio and visual data, multimedia systems, and file storage formats. It was originally introduced in late 1998 as a group of audio and video coding formats and related t ...

Theora Theora is a free lossy video compression format. It is developed by the Xiph.Org Foundation and distributed without licensing fees alongside their other free and open media projects, including the Vorbis audio format and the Ogg container ...

, VP8 and H.264 (with a plugin based on

x264 x264 is a free and open-source software library and a command-line utility developed by VideoLAN for encoding video streams into the H.264/MPEG-4 AVC video coding format. It is released under the terms of the GNU General Public License. Hi ...

), with resolutions from QCIF (176×144) to SVGA (800×600) provided that network bandwidth and CPU power are sufficient.Linphone.org » Features

Gallery

Linphone-1-linux-gnome.png, One of initial version's interface of Linphone in

(

GNOME A gnome is a mythological creature and diminutive spirit in Renaissance magic and alchemy, first introduced by Paracelsus in the 16th century and later adopted by more recent authors including those of modern fantasy literature. Its characte ...

) linphone on htc desire.jpg, Linphone running on

HTC Desire The HTC Desire (codenamed Bravo) is the first smartphone of the Desire series developed by HTC. It was announced on 16 February 2010 and released in Europe and Australia in the second quarter of the same year. The HTC Desire was HTC's third ...

Linphone-4.1.1-screenshot.png, Linphone 4.1 working on

Windows 8 Windows 8 is a major release of the Windows NT operating system developed by Microsoft. It was released to manufacturing on August 1, 2012; it was subsequently made available for download via MSDN and TechNet on August 15, 2012, and later to ...

(main screen) Linphone-4.1.1-windows-settings.png, Linphone 4.1 settings on

References

External links

* {{Portal bar, Free and open-source software Cross-platform software Android (operating system) software Free and open-source Android software Communication software Free VoIP software Instant messaging clients Instant messaging clients for Linux IOS software MacOS instant messaging clients Videotelephony VoIP software Windows instant messaging clients BlackBerry software