This is a Voice over Internet Protocol (VoIP) and streaming media service based on the Session Initiation Protocol (SIP) by which Internet telephony service providers (ITSPs) deliver telephone services and unified communications to customers equipped with SIP-based private branch exchange (IP-PBX) and Unified Communications facilities
Virtual phone numbers provider with free advanced phone system included. Can connect VoIP phones in for incoming/outgoing. Multiple other forwarding options available.