Front-End Processor

The front-end processor handles the incoming and outgoing communications exchanges between the host computer and the peripheral terminals and other host computers both inside and outside the network. Thus, the front-end processor serves as both an input unit and output unit for the host computer. Usually, the front-end processor is a minicomputer, while a mainframe serves as the host.

Certain front-end processors can send messages from one terminal to another without involving the host computer. This ability is known as message switching. Front-end processors that perform message switching usually have a store and forward capability. When a terminal is unable to receive a transmission at a particular time, the front-end processor will hold the message in its secondary storage and resend it later.