Page 140 - DCAP104_EXPOSURE_TO_COMPUTER_DISCPLINES

Unit 6: Data Communication

6. What does a data communication system need to carry data from one location to another? Notes
(a) Bandwidth.
(b) Data transmission channels.

(c) Standard telephone line.
(d) Telegraph system.
7. A bandwidth determines the volume of data that can be transmitted in a given time?
(a) True (b) False

8. Broad-band channel transmit data at speeds over 100 000cps. Which cable provides very
high frequency signals that can be transmitted over space?
(a) Coaxial cables.
(b) Fiber Optics Cables.

(c) Communication Satellites.
(d) Microwave Signals.
9. Which transmission lines permits data to flow in one direction only i.e. you can send or
receive data but not both?
(a) Full-duplex line.
(b) Half-duplex line.
(c) Simplex line.
(d) Coaxial line.

10. Which transmission line permits data to be sent alternatively, i.e. you can send and receive
but not at the same time?
(a) Simplex line.

(b) Coaxial line.
(c) Half-duplex line.
(d) Full-duplex line.

6.9 Review Questions

1. What do you mean by data communication?

2. Explain the general model of data communication. What is the role of modem in it?
3. Explain the general model of digital transmission of data. Why is analog data sampled?
4. What do you mean by digital modulation?
5. Explain various digital modulation techniques.
6. What are computer networks?

7. What do you mean by network topology?
8. How data communication is done using standard telephone lines?
9. What is ATM switch? Under what condition it is used?
10. What do you understand by ISDN?

11. What are the different network methods? Give brief introduction about each.

LOVELY PROFESSIONAL UNIVERSITY 133