Summary

Chapter 8: Fundamental Networks 53PLC is known by other names:■■■Power Line Networking (PLN)Mains communicationPower Line Telecom (PLT)With PLC, an electric company can superimpose an analog signal over the standard 50- or60-Hz AC that travels in power lines. The analog signal can carry voice and data signals.PLC may be available in areas where other high-speed connections are not. PLC is fasterthan an analog modem and may cost much less than other high-speed connection types. Asthis technology matures, it will become more common to find and may increase in speed.You can use PLC to network computers within your home instead of installing networkcabling or wireless technology. PLC connections can be used anywhere there is an electricaloutlet. You can control lighting and appliances using PLC without installing control wiring.Define BroadbandBroadband is a technique used to transmit and receive multiple signals using multiple frequenciesover one cable. For example, the cable used to bring cable television to your homecan carry computer network transmissions at the same time. Because the two transmissiontypes use different frequencies, they do not interfere with each other.Broadband is a signaling method that uses a wide range of frequencies that can be furtherdivided into channels. In networking, the term broadband describes communication methodsthat transmit two or more signals at the same time. Sending two or more signals simultaneouslyincreases the rate of transmission. Some common broadband network connectionsinclude cable, DSL, ISDN, and satellite.CableA cable modem connects your computer to the cable company using the same coaxial cablethat connects to your cable television. You can plug your computer directly into the cablemodem, or you can connect a router, switch, hub, or multipurpose network device so thatmultiple computers can share the connection to the Internet.DSLWith DSL, the voice and data signals are carried on different frequencies on the coppertelephone wires. A filter is used to prevent DSL signals from interfering with phone signals.Plug the filter into a phone jack, and plug the phone into the filter.The DSL modem does not require a filter. The DSL modem is unaffected by the telephonefrequencies. Like a cable modem, a DSL modem can connect directly to your computer, or