Issabel
Your Open Source Solution For Unified Comunnications And More… Issabel™ is a free and open source software that allows you to build communication tools for businesses.
Wazo
Wazo is mainly an IPBX that provides communication services such audio, video, and instant messaging based on the use of stand ...
FusionPBX
FusionPBX is an open source FreeSWITCH GUI. FusionPBX can be used as a high available single or domain based multi-tenant PBX, ...
Elastix
Elastix is an open source Unified Communications Server software that brings together IP PBX, email, IM, faxing and collaborat ...