Lesson 4.7

4.7       WHAT YOU HAVE LEARNT

In this lesson we discussed the importance and modes of communication through computers. Computers can communicate with one another through computer networking. There are two types of computer network: LAN and WAN. We discussed about the physical arrangements of computer and peripherals in network topology. There are three types of network topology: star topology, bus topology and ring topology. Also we discussed about Internet and e-mail.

4.8       TERMINAL QUESTIONS

1.   What is computer Network?   What are its main objectives?

2.   Differentiate between analog and digital transmission of data.

3.   Explain in brief different communication media.

4.   What is the difference between simplex and full-duplex transmission?

                                                                                                                                               

4.9       FEEDBACK TO IN-TEXT QUESTIONS                       

IN-TEXT QUESTIONS 1

1.      The data communication software instructs computer systems and devices as to how exactly data is to be transferred from one place to another. The procedure of data transformation in the form of software is commonly called protocol.

2.      In asynchronous transmission data is transmitted character by character as you go on typing on a keyboard. On the other hand, in the synchronous mode, the saved data is transmitted block by block.

3.          (a) True             (b) False          (c) True            (d) True           (e) True

IN-TEXT QUESTIONS 2

1.      LAN is restricted to limited geographical area whereas WAN covers great distance. In LAN the computer terminals and peripheral devices are connected with wires and coaxial cables whereas in WAN communication is done through telephone lines and satellite links. The speed of data transmission is much higher in LAN than in WAN.

2.      There are three major types of network topology. They are star topology, bus topology and ring topology.

3.   (a) False       (b) True         (c) False           (d) True           (e) True

IN-TEXT QUESTIONS 3

1.      The Internet is a network of networks. Information in every field starting from education, science, health, medicine, history, and geography to business, news, etc. can be retrieved through Internet.

2.      E-mail stands for electronic mail. Through e-mail we can transfer data anywhere in the world within seconds.

3.      Internet is not a governmental organisation. The ultimate authority of the Internet is the Internet Society. This is a voluntary membership organisation whose purpose is to promote global information exchange.