VIVA offers IP based Converged Communications Solutions. You may contact VIVA for SIP Trunking, IP PBX & PSTN integration, MS OCS & IP PBX integration, Managed VoIP and ''''Secure'''' VoIP.
It is the business practice of sending all clients' billing info to a separate company, who then does everything for you. It also allows a company to cut down on time and human resources spent on administrative tasks.