Asterisk

Asterisk is free software that transforms a computer into a communication server. Asterisk lets you build applications like PBX, VoIP gateway, IVR and ACD.

Free Open Source Mac Windows Linux

freepbx

FreePBX is a web-based open source GUI (graphical user interface) that controls and manages Asterisk (PBX), an open source communication server.

Free Open Source Linux

Wazo

Wazo is a unified communications platform based on Asterisk and focused on extensibility.

Free Open Source Mac Windows Linux Self-Hosted

3CX Phone System

3CXPhone is a free VoIP phone available for Windows, iPhone or any Android based smart phone such as Google Nexus, Sony Xperia, Motorola Droid or Samsung Galaxy. Connect...

Freemium Windows Android iPhone

Starfish PBX

Starfish PBX aims to be an open source alternative to Digium’s Switchvox. The goal is to have a software equivalent to which we can add additional functionality like: ...

Free Open Source Linux

Elastix

Elastix is an open source Unified Communications Server software that brings together IP PBX, email, IM, faxing and collaboration functionality. It has a web interface...

Freemium Linux

XiVO

XiVO is an IP-PBX, a unified communications platform that connects phones on a local or private network with other networks such as public landlines and mobile...

Free Open Source Mac Windows Linux

Yate - Yet Another Telephony Engine

Yate is a softswitch (concept of separating the network hardware from network software). It supports VoIP protocols: H.323, SIP, IAX1, IAX2, RTP. For the plain old...

• Requires "a lot of" appliances to work, you must spend a lot of money to do this. With FreeSwitch you need a PC, OpenVox Card and ready. Guest • Aug 2015 Disagree   Agree

Free Open Source Linux

opensips

OpenSIPS (Open SIP Server) is a mature Open Source implementation of a SIP server. OpenSIPS is more than a SIP proxy/router as it includes application-level...

Free Open Source Linux

unxsVZ uSIPSwitch

uSipSwitch a micro sip switch (sip proxy) perfect for edge SIP SBC work (e.g. hosted PBX business). Comes with web console and DNS health tools. Uses modern clustering...

Free Open Source Linux

Kamailio

Kamailio® (successor of former OpenSER and SER) is an open source SIP server released under GPL, able to handle thousands of call setups per second. Among features:...

Free Open Source Linux

AsteriskNOW

AsteriskNOW is the fastest way to get started building custom telephony solutions with Asterisk. Simply download the .iso file, burn it to a CD, drop it into the CD or...

Free Linux

Zent.io

Zent.io is a Contact Center Cloud Software Multichannel that unify chat, phone and e-mail. All the communication channels will be answered from a single interface. The...

Commercial $ $ $ Mac Windows Linux Web

VoipSwitch

VoipSwitch is a SoftSwitch System with routing and billing, with SIP protocol support (in older versions also H323). Basic package includes softswitch app, IVR app...

Commercial Windows

PBX in a Flash

PBX in a Flash is a PBX system based on Asterisk, FreePBX and CentOS, coming as an ISO download. A two stage installation process allows for more flexibility for the...

Free Open Source Linux