An IP PBX is nothing but the ordinary PBX which handles VoIP calls and delivers the users with additional features and more. The Website whichvoip.com is one among the service providers who makes use of the IP PBX features and the major advantage is that you can retain control on the system and the responses to the situations is very fast compared with other providers. This website takes care of the installation as this is on premises equipment which requires great skills to handle and operate. This solution offered by IP PBX is a great advantage for large enterprises which could offer the cost in taking care of this and the same is not possible for small organizations as they cannot afford the required staff to maintain the equipment.