Asterisk - An open source telephony switching and private branch exchange service for Linux.
Dialpad - Switch is a cloud-based phone system built for Google Apps users.
FreeSWITCH - FreeSWITCH is an open-source media application designed to support popular protools such as SIP and WebRTC and provides a platform to develop voice and video applications.
Genesys Cloud - As the foundation of great customer experience, the Genesys PureCloud contact center platform empowers your business to provide excellent service across the entire customer journey.
Wazo.io - The UCaaS Platform Built for MSPs
8x8 X Series - X Series connects teams across channels and around the globe, giving you access your most critical information securely, from any location.