An IP-PBX is a Public / Private Switched Telephone Network private branch exchange (telephone switching system within an enterprise) that switches calls between VoIP (voice over Internet Protocol or IP) users on local lines while allowing all users to provides internal & external communication for a business. An IP PBX is a PBX system with IP connectivity and may provide additional audio, video, or instant messaging communication utilizing the TCP/IP protocol stack.
EPABX is an equipment that has made day-to-day working in the offices much simpler, especially in the field of communications. The EPABX may be defined as a switching system that makes available both internal and external switching functions of any organisation. By using an EPABX fully served. With the advent of powerful microprocessors and advancements in the field of computers, the EPABX can boast of versatile features. Hotline can be established between the boss and his immediate subordinates.