The EPABX is an acronym of Electronic Private Automatic Branch Exchange. An EPABX has three main components (1) the analog system and analog to digital converter which is basically the various line cards and (2) the cross connection matrix which connects one call to another and (3) the control of the whole EPABX.

The EPABX stand for Electronic Private Automatic Branch Exchange. which means it is an electronic exchange which is privately owned and automatic. It is also known as PBX and PABX.

The first part (1) deals with the analog system i.e. your voice coming on two wires and the associated signalling. It converts the signalling as well the voice into digital and handovers to the matrix. The matrix checks for which port (the no. you dial is just a port of it) is the call meant for and digitally connects the respective port to the calling port.

The call is established and held as long as you keep the receiver off hook. The third part maintains the normal functioning of the EPABX including power supply, configuration, troubleshooting and generation of various reports.