I have been looking for a decent open source VoIP project. Here are some good ones I have found so far:
wxCommunicator is a cross platform open source SIP softphone enabling users to make multiple calls, use several accounts, chat and create conferences. It is very configurable and should work with any VoIP provider. It is based on customized sipXtapi client library and wxWidgets 2.8.x GUI library and distributed under GNU GPL version 2 licence.
VMukti is leading Asterisk/ Yate enabled p2p Video IP Communications Suite for Web / PSTN. These serverless broadband ready platform enable OS community to save 90% on capital & operating costs over proprietary software for conferencing & Call Center.
GibPhone is a highly extensible VoIP/IM client for the .NET framework that uses a powerful plugin engine to allow for UI extensions and any call control stack / media payload / transport protocol combination.
Ekiga (formely known as GnomeMeeting) is an open source VoIP and video conferencing application for GNOME. Ekiga uses both the H.323 and SIP protocols. It supports many audio and video codecs, and is interoperable with other SIP compliant software and also with Microsoft NetMeeting.
TStone is a p2p voip system.It can run on windows or linux. It supports h.323 and sip signaling.It is writed by c/c++ code
- Landell Voip Application
A Voip GUI write in C#, based in Tapioca-Voip framework, 100% compatible with Gtalk.
- Peer to Peer Chat in C#
Using Microsoft's Peer-to-Peer technology and Adrian Moore's encapsulation, to create an easy to use library for chatting.
- SIP Stack with SIP Proxy
C# implementation of SIP
- Sipek SDK
SipekSDK is a small VoIP Software Development Kit written in C#. The goal of SipekSDK is to offer simple and easy to use API for VoIP developers.
- My SIP Switch
A SIP signalling consolidation tool that allows multi-user management of diverse SIP providers and allows central management of any SIP based VoIP service. Included in this project are a SIP Stack, SIP Registrar, SIP Registration UAC, SIP Stateful Proxy, STUN Server and more. The components are all written in C#.