Cable Modem Vs. Traditional (Telephone) Modem
Source: University of Rhode Island
In the 1960s, modems (Modulator-Demodulators) were developed to permit the transmission of digital signals over telephone lines. The modulator of a modem converts bits into sounds in the frequency range transmitted by the telephone lines, and the demodulator converts such sounds back into bits. Until recently, the only way to transmit information between home computers and the Internet was through telephone-based modems. A Cable Modem is a device that allows high-speed data access via a cable TV (CATV) network. Most cable modems are currently external devices that connect to the PC through a standard 10 BASE-T Ethernet card and twisted-pair wiring. Like telephone modems, cable modems link to computers to translate data, called "Modulation and Demodulation", converting data from digital to analog and vice versa.