A PBX (private branch exchange) is a telephone system within an enterprise that switches calls between enterprise users on local lines while allowing all users to share a certain number of external phone lines. The main purpose of a PBX is to save the cost of requiring a line for each user to the telephone company’s central office.
A PBX includes:
- Telephone trunk (multiple phone) lines that terminate at the PBX
- A computer with memory that manages the switching of the calls within the PBX and in and out of it.
- The network of lines within the PBX
- A console or switchboard for a human operator (optional)
IP Telephony:
IP telephony (Internet Protocol telephony) is a general term for the technologies that use the Internet Protocol’s packet-switched connections to exchange voice, fax, and other forms of information that have traditionally been carried over the dedicated circuit-switched connections of the public switched telephone network (PSTN). Using the Internet, calls travel as packets of data on shared lines, avoiding the tolls of the PSTN. The challenge in IP telephony is to deliver the voice, fax, or video packets in a dependable flow to the user. Much of IP telephony focuses on that challenge.
In today’s word IP Telephony is more used to communicate with multiple branches and share information.
