A model for the local area of a data communication network software organization

Abstract

A general purpose store-and-forward data communication network is under development at NPL. The background to this work is described in companion papers(1)(2) which also detail the hardware environment in which the software of the central message switching computer (MSC) operates. A user of this system sees it as a star-connected network by means of which his terminal may exchange data with any other terminal via the MSC. Because this centre is stored-program controlled, it is possible to offer the user other communications-oriented facilities in addition to the basic data transmission function. The MSC may be described as a multi-access computer controlled by a timesharing operating system. Section 2 gives a description of the way in which terminals use the network, illustrating the main principles of operation of the system as a whole and outlining the features provided by software. Section 3 is a description of the operating system of the MSC.