The Asynchronous Transfer Mode has been chosen as the standard system concept for integrated broadband communication networks by the ITU﷓T. The system is predicted to grow rapidly as soon as it becomes widely accepted by network operators and users. Why has communications evolved in history towards the ATM concept and why has it been chosen as the broadband solution? In the late 1800's public telephone networks capable of transmitting analogue voice signals were established. The users were connected together via switches across the network to form a circuit. This was the first transfer mode used in telephone networks, and it is known as