Computers get chatty

Abstract

The telegraph was the first true data network. Although it was normally restricted to just one form of data (text), it was certainly capable of carrying others (such as facsimile). It could not, however, carry voice. It was not until the arrival of the telephone in the late nineteenth century that voice started to challenge data as the dominant form of traffic on public networks. By the middle of the twentieth century, networks were overwhelmingly designed to carry voice, but within 50 years, the pendulum was swinging back towards data. This occurred because developments in digital computing and the arrival of the Internet meant that computers were now able to talk to other computers. They turned out to have a lot to say! Today, data is once again the dominant form of traffic on most networks. In this chapter, we introduce some of the key features of data networks.