ABSTRACT
We are in a period of scientific revolution in considering wired telecommunications. The technology of transmitting information by means of manipulating electrons has, from engineering and economic viewpoints, a considerably different optimization than do photons of light. The tendency of the 1980s has been to imitate the past. But mimicking electronics can be costly of effort, reliability, and energy when working with the optoelectronic and the photonic technologies. Nevertheless, so much effort has been expended throughout the world that a transition period is being directed by the administrations of many of the telecommunications organizations of the world. This portion of the book emphasizes the transition between science and engineering. The latter now encompasses optoelectronic and photonic switching in advanced telecommunications. Advanced electronic and optical telecommunications will undoubtedly coexist, but in differing and changing degrees. As the enormous advantages become apparent, the change becomes possible. Thus, certain video switches for the subscriber loop of telecommunications are inherently expensive, using electronic switching or repeaters with conversions from one form of energy to another continuously throughout transmission. Solutions using optoelectronic or photonic technology often provide more effective results.
