Linphone
2.2.1.1 (Android) November 14, 2013
2.1.2 (iOS ) November 22, 2013
1.0.1 (BlackBerry) January 11, 2011
1.0.2 ( Windows Phone ) November 25, 2013
Linphone is a free software for IP telephony ( VoIP), which is available under GNU GPLv2. It is a simple and reliable VoIP program with video transmission. Because of the fairly good video quality, it is suitable also for example conversations in sign language.
The program is available in a Linux, Windows and Mac OS X version for unix like operating systems, the freely available source code can be used. In addition, clients for Android, iOS, BlackBerry and Windows Phone exist. In addition to the GTK - based graphical interface, two console programs exist.
The program has the following features:
- Internet telephony - based on the SIP standard
- Video telephony or video conferencing
- Presence (you can tell if a caller is currently reachable )
- Encryption of audio and video transmission
For voice transmission, the following codecs are available:
- G.711a or G.711u
- GSM
- Speex
- LPC10 -15
- G.722
- Opus
Video transmissions can be performed with the following codecs:
- H.263 or H.263
- MPEG4 Part 2
- Theora
- H.264 ( with plug- in based on x264 )
Encryption may be performed with the following protocols:
- SRTP
- ZRTP
For the operation behind a NAT router is the STUN protocol.