In its concept, the technology of cable television is relatively simple. It is a system of wires and amplifiers used to gather television and radio signals from a variety of sources and deliver them to the homes in a given geographic area. It is sometimes compared with the water system of a city, which takes water from one or two primary sources and distributes it to customers throughout the city. Cable television similarly distributes a roster of television channels to all the residents of an area who connect to its wire. Cable systems are expanding their services to include high-speed Internet access and traditional telephone service as well. The fundamental components of a cable system include the main office of the local system, called a "headend," where the various signals are gathered, combined, and fed out into the system; fiber-optic...