The development of telephony in the last fifty years: From the two-party lines to the video-phone connections

Abstract

This short paper reviews the changes in telephone technology that have taken place over the last 50 years. Electromechanical technique, semi-electronic, electronic, digital and packet is mentioned. The structure of the switching field changed as well: from expensive space multiplex to elegant time multiplex. Basic features of packet and mobile telephony are given. New properties were mentioned for each technique. The changes in signalling systems, numbering, theory of telecommunication traffic were mentioned. The development of modern telephone technics has increasingly included programs to simulate random processes, for checking the traffic calculations.

Keywords

• telephony
• internet
• mobile telephony