Data Communications

Abstract

Communication has always been important, and lack of communication in the past has resulted in terrible wars and tragedies. It could be said that the reason that we have had world peace for so long is more to do with global communications, than with diplomacy. The great growth of communications has revolved around three main technologies: the telephone, television and radio. All three initially involved the transmission of analogue signals over wires or with radio waves. On an analogue telephone system, the voltage level from the telephone varies with the voice signal. Unwanted signals from external sources easily corrupt these signals. In a digital communication system, a series of digital codes represents the analogue signal, which are then transmitted as 1’s and 0’s. These digit forms are less likely to be affected by noise and thus, have become the predominant form of communications.