Читать книгу Sociology - Anthony Giddens - Страница 185

The explosion in global communications has been facilitated by a number of important technological advances. Since the Second World War, there has been a profound transformation in the scope and intensity of telecommunication flows. Traditional telephonic communication, which depended on analogue signals sent through wires and cables with the help of mechanical crossbar switching, has been replaced by integrated systems in which vast amounts of information are compressed and digitally transferred. Cable technology has become more efficient and less expensive, and the development of fibre-optic cables has dramatically expanded the number of channels that can be carried.

The earliest transatlantic cables, laid in the 1950s, were capable of carrying fewer than 100 telephone channels, but by 1992 a single transoceanic cable could carry some 80,000 channels. In 2001, a transatlantic submarine fibre-optic cable was laid that is capable of carrying the equivalent of a staggering 9.7 million telephone channels (Atlantic Cable 2010). Today, such cables carry not just telephony but internet traffic, video and many other types of data. The spread of communications satellites orbiting the planet, beginning in the 1960s, has also been significant in expanding international communications. Today, a network of more than 200 satellites is in orbit facilitating the transfer of information around the globe, though the bulk of communication continues to be via submarine cables, which are still more reliable.