Asterisk (PBX)

open source software implementing a private branch exchange for various Voice over IP protocols

computer network protocol

computer engineer

LinuxMCE (Linux Media Center Edition) is a free and open source software platform with a 10-foot user interface designed to allow a computer to act as a home theater PC (HTPC) for the living-room TV, personal video recorder, and home automation system. It allows control of everything in the home, from lighting and climate to surveillance cameras and home security. It also includes a full-featured VoIP-compatible phone system with support for video conferencing.

Elastix is a unified communications server software that brings together IP PBX, email, IM, faxing and collaboration functionality. It has a Web interface and includes capabilities such as a call center software with predictive dialing.

Digium, Inc. is a communications technology company based in Huntsville, Alabama, and since 2018, a subsidiary of Sangoma Technologies Corporation. The company makes VoIP business phone systems, IP phones, and hardware products. It was founded in 1999 by Mark Spencer.

trixbox (formerly Asterisk@Home) was a software PBX based on Asterisk.