Private branch exchange (PBX):
A private branch exchange (PBX) is a private or leased telephone switching system that connects telephone extension in-house. (A switched line is a communication line that connects through a switching system to a variety of destinations.)A PBX also connects users to outside telephone system.
A public telephone system consists of “public branch exchanges” thousands of switching stations that direct calls to different “branches” of the network. A branch exchange is essentially the old- fashioned company switchboard you call in form of the outside. New PBXs can handle not only analog telephones but also digital equipments, including computer. however, because older PBXs use existing telephone lines, they many lots be able to handle the volume of electronic messages found in some of the today’s organization. These companies may be better served by LANs.
Local area network (LAN):
PBXs may share existing phones lines with the telephone system. The local area networks usually require installation of their own communication channel, whether wired or wireless. Local area networks (LANs) are local networks consisting of a communications link, network operating system software, microcomputers or workstation’s servers, and other shared hardware. Such shared hardware might include printers, scanners, and storage devices. Unlike larger network, LANs do not use a host computer.