The word "broadband" is used to refer to any kind of Internet service that provides high-speed, continuous Internet access. Digital subscriber line, or DSL, is always broadband, but it is not the only kind of broadband. Different broadband services use different wiring and transmission systems to connect users to the Internet, but they are all high-speed.
DSL uses the telephone wiring in a building to connect to the Internet, sending signals from the computer's modem to the Internet service provider's modem over the telephone line in digital form. Like all broadband services, DSL stays connected to the Internet all the time and does not require users to connect and disconnect like dial-up does. Even though it uses phone lines, DSL allows users to make phone calls while they use the Internet.
Cable broadband Internet uses a building's coaxial cables that transmit data to its televisions. A cable plugs into an outlet in the wall on one end and the cable modem on the other, and a second cable runs from the modem to the computer. Users can watch cable television and access the Internet at the same time. This kind of connection is very similar to DSL in terms of speed and quality of service, and it does not require a phone line to install.
Fiber-optic broadband Internet connections use wires made of slim glass filaments to transmit data from an Internet service provider to a computer. The data travels as light down the glass fibers, giving it a greater download and upload speed than any other kind of high-speed Internet. Fiber-optic Internet services require the installation of these special wires, unlike DSL and cable, which use the wires already present in the building.
Wireless and Satellite
Wireless broadband Internet services transmit data from the service provider to the user's computer via radio waves, so they do not require the computer to be connected to any kind of external modem or line. Computers do need an internal wireless card to receive the signal. Satellite Internet services transmit data from satellites to a small dish installed outside the user's home or office. The dish is connected to sending and receiving equipment, which is in turn connected to the user's computer.
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