1. Modems Presented By PalwinderKaur 8/19/2010 How Modem Works!! 1

2. Modem Formal Definition “A modem (modulator-demodulator) is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. So it is Data Conversion Equipment”. 8/19/2010 How Modem Works!! 2

3. The Origin of Modem 8/19/2010 How Modem Works!! 3

4. Classification of Modems Based on Range Short Haul Voice Grade Wide Band 8/19/2010 How Modem Works!! 4

5. Continue… Based on Line Type Dialup Leased /Private 8/19/2010 How Modem Works!! 5

6. Continue Based on Operation Mode Half Duplex Full Duplex Simplex 8/19/2010 How Modem Works!! 6

7. Types of Modem Internal Modem External Modem 8/19/2010 How Modem Works!! 7

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9. How it Works 8/19/2010 How Modem Works!! 9

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11. Speed Variations From 1960 to till now!! 300 bps - 1960s through 1983 or so 1200 bps - Gained popularity in 1984 and 1985 2400 bps 9600 bps - First appeared in late 1990 and early 1991 19.2 kilobits per second (Kbps) 33.6 Kbps 56 Kbps - Became the standard in 1998 ADSL, with theoretical maximum of up to 8 megabits per second (Mbps) - Gained popularity in 1999 8/19/2010 How Modem Works!! 11

12. Future Trends 8/19/2010 How Modem Works!! 12