Video conferencing and collaboration platform
Open-source event-driven AI powered Softphone
Issabel PBX - Unified Communications
VoIP SIP and SKINNY quality analyzer and packet / audio recording tool
VoIP/SIP SoftPhone (formerly known as jphonelite)
ICTCore: Unified Communications Framework for web developers
SMS, Fax, Voice Broadcasting and auto dialer Software
Unified Communications Server
Unified Communications System - PBX System
Emulates Cisco TMS PhoneBook for CMM or Endpoints with PHP
Jitsi is an audio/video and chat communicator that supports protocols
Java VoIP Softphone (SIP) (replaced by jfPhone)
VoIP/SIP Autodialer
for Adium, Pidgin, Miranda and Telepathy IM Framework
A Better PBX For Your Business
Accent interfaces and controls systems through goals and policies
Enterprise telephony recording and retrieval system
SIP softphone
SIP Video Multiconference Media Server with WebRTC support.