Twinkle is a software phone for voice over IP communications using the SIP protocol. You can use it for direct IP phone to IP phone communication, or in a network using a SIP proxy to route your calls. Some of the features offered are call waiting, call hold, 3-way conference call, call transfer, and call reject. It supports STUN or a statically configured public IP address for NAT traversal. When using STUN, it will send keep-alive packets to keep NAT bindings alive. It supports ZRTP for secure voice communication.
License: GNU General Public License (GPL)
Changes:
Sound did not work when Twinkle was compiled without speex support. Compiling Twinkle without KDE support sometimes failed. These problems have been fixed.
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