Front end processor

A front end processor (FEP), or a communications processor, is a small-sized computer which interfaces to the host computer a number of networks, such as SNA, or a number of peripheral devices, such as terminals, disk units, printers and tape units. Data is transferred between the host computer and the front end processor using a high-speed parallel interface. The front end processor communicates with peripheral devices using slower serial interfaces, usually also through communication networks. The purpose is to off-load from the host computer the work of managing the peripheral devices, transmiting and receiving messages, packet assembly and disassembly, error detection, and error correction. Two examples are the IBM 3705 Communications Controller and the Burroughs Data Communications Processor.
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A programmed-logic or stored-program device that interfaces data communication equipment with an input/output bus or memory of a data processing computer.

(FEP) 1. A small computer necessary to enable an IBM mainframe using SNA to communicate beyond the limits of the dinosaur pen.
2. A small computer controlling the screen and keyboard of a Symbolics 3600 LISP Machine.