Modem stands for modulation and demodulation. It is a communication device used to transfer the data using telephone line. It converts analog signals into digital signals and vice versa.
- It is a device that converts digital data into analog for transmission over analog network medium and then back to digital at the receiving end.
- The modem works on two phase:
- First phase is modulation phase: In this phase, the device translates the digital signals of computer to analog signals, which are then transmitted to the telephone line.
- Second phase is demodulation: In this phase, the device converts the analog signals received from the telephone line into digital signals for the computer.
Modem are of different types:
- Telephone (POTS - Plain Old Telephone Service)