The document discusses various aspects of data communication. It explains how modems convert digital data to analog signals to transmit over standard telephone lines, and how different digital connections like ISDN, DSL, and cable modems transmit data at higher speeds. It also describes wireless communication technologies like WiFi, WiMAX, and how they enable local and wide area networking using radio waves. Diagrams provide simple illustrations of data communication systems using these various modes of transmission.

1. Presented by:
Md. Akid Sultan Khan
ID:1104067
CSE,CUET.

2. Objective
Explain Data Communication.
Show some simple diagram for Data
Communication.
Explain about modems.
Explain various wireless communication.

3. Aim
Show some aspects of Data Communication
& types of varieties in this extra-ordinary
sector of communication.

4. Definition
Refers to the moving or transferring of data
between two electronic devices.

5. Simple Data
Communication system

6. Data Communications over Standard
Telephone Lines - Modems
Most telephone lines are analog, not digital.
modem converts it from analog format to
digital format.

7. `
The analog signal
(audible)
is sent through
telephone lines.
011010001 MODEM MODEM 011010001
Digital signal Digital signal
This modem converts This modem converts
digital to analog. analog to digital.

8. Internal
External
Modem Modem

9. Using Digital Data Connections
Dedicate to transmitting data in digital
format.
Transmit data at much higher speeds than
standard analog phone lines.

10. Diagram of digital data connections
1 2
4
3

11. Broadband Connections
transmit data faster than is possible through
a standard dial up connection using a
modem.
 The most commonly used digital telephone
services are:
 ISDN,T1 and T3
 DSL
 Cable Modems
 ATM

12. Wireless communication
Use RF or IR to transmit data between
devices on LAN.
Wireless signals are electromagnetic waves
that can travel through a vacuum of outer
space.

13. Categories of wireless
Communication
WiFi
WIMAX
WAN
WLAN

14. Local Area Networks
(LANs)
Connected by a cable, infrared link, or small
transmitters.
Transmits data by breaking it into small
pieces.
Every LAN uses a protocol.

15. LAN Communication Sample

16. Wide Area Networks (WANs)
transmit data over leased high-speed phone
lines or wireless links such as satellites.

17. LAN 2
LAN 1
WAN

18. WiMAX
Provide 30 to 40 megabit-per-second data
rates.
 Enable to delivery of last mile wireless
broadband access .

19. Simple WiMAX Communication
system

20. Wi-Fi
radio waves to provide wireless high-speed
internet and network connections
easily accessible in the corporate
infrastructures

21. Simple WiFi System

22. Conclusion
In this presentation we
Explain how computer data travels over
telephone lines.
Explain a modem’s function.
Differentiate four types of digital data
connections.
Describe how wireless networks functions.

24. Any
Questions???