8x8 X Series - X Series connects teams across channels and around the globe, giving you access your most critical information securely, from any location.
Asterisk - An open source telephony switching and private branch exchange service for Linux.
Vonage Business Communications - Vonage Business Communications transforms communications and activates conversations anytime, anywhere. Learn more about unified communications now!
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.
Broadvoice - Cloud PBX solution for SMBs
Wazo.io - The UCaaS Platform Built for MSPs