Private automatic branch exchange (PABX) is an automatic telephone switching system within a private enterprise. Originally, such systems – called private branch exchanges (PBX) – required the use of a live operator. Since almost all private branch exchanges today are automatic, the abbreviation “PBX” usually implies a “PABX.”
Private automatic branch exchange (PABX) is a technology used by call centers and other large organizations that allows a single access number to provide several lines to outside callers while providing a range of external lines to internal callers or staff. PABX performs all the switching necessary for making internal calls between extensions within the organizations. It also allows provides a connection between extensions and external phone lines.