Modem

Abstract

Modem is a device which converts digital signals to audio frequency tones and vice versa. The frequency of these signals is within the frequency range of telephone lines. Through telephone lines, these signals are transmitted and then converted back to digital information. The term ‘MODEM’ is a contraction of modulator-demodulator. Modems allow two computers/terminals to communicate and to send serial data over long distance using telephone line i.e. they are basically used as interface between the telephone lines and the computer for transmitting and receiving datas. They are therefore being called as Data Modems also. Early nineties low speed modems with data rate of 2400/ 4800 bps were being used.