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
Citel is The VoIP Migration Company™. We develop the world''s most comprehensive portfolio of network-edge products enabling enterprises to realize the cost and productivity benefits of IP telephony.