- audio with the following codecs: speex (narrow band and wideband), G711 (ulaw,alaw), GSM, and iLBC (through an optional plugin)
- video with H263-1998, MPEG4 and theora codecs.
- Supports any webcam with V4L or V4L2 driver under linux
- Any webcam on windows
- text instant messaging and presence (using the SIMPLE standart)
- Addressbook
- DTMF (telephone tones) support using SIP INFO or RFC2833
- understands SIP ENUMS (sip phone numbers using the naptr DNS service, without proxy)
- echo cancelation using the great speex echo canceler
- SIP proxy support: registrar, proxies, with digest authentication
- STUN support for traversal of UDP NATs (=firewall)
- sound backend using either ALSA (the most efficient), OSS, or arts (kde sound daemon)
- supports IPv6
- the bandwidth limitations are signaled using SDP (b=AS...), resulting in audio and video session established with bitrates that fits the user's network capabilities.
On linux, linphone can be used as a small GNOME/GTK+ application or as a console mode application (the executable is called 'linphonec'). The existence of this console mode application gives the possibility to run VoIP calls from scripts, or to run linphonec as a small auto-answering phone.
On windows, it is available as graphical application.
Linphone is known to work under Linux, Windows, FreeBSD, OpenBSD.
The console version (linphonec) run on arm-linux. Instructions for arm cross-compilation are given in the README.arm file within linphone's source.
Additionaly it has been reported to work on several embedded chips: search google or the mailing lists for more details.
Here is the non-exhaustive list of standarts linphone is using;