The use of computers in message switching networks

This paper presents a tutorial discussion of message switching systems. The emphasis is on utility and operational aspects, although design considerations of an individual message-switching center are also covered. A message-switching network is described and the difference between its operation and that of a circuit-switching network is pointed out. A message is traced through the system, from a sender to a receiver. Concepts are introduced of a multi-address message, exchange between subscribers using different terminal equipment and of the use of high-speed trunks.The interrelationship among messages being processed is discussed, with special attention being given to the queuing of messages, including the complexities of message priorities and message pre-emption. Message protection measures are discussed briefly, along with the necessity of virtually continuous operation. The paper ends with a presentation of a typical configuration of a message-switching center, with both hardware and software implications.