Page 225 - PYTHON-12

10. Illustrate the layout for connecting five computers in a Bus and a Star topology of Networks.
Ans. Bus topology

Star topology

11. In networking, what is WAN? How is it different from LAN? [CBSE D 2011]
Ans. Internet is an example of WAN (Wide Area Network). Most WANs exist to connect LANs that are not in
the same geographical area. WAN is different from LAN due to its network range. WAN is for connecting
computers anywhere in the world without any geographical limitation whereas LAN is confined within
a range of 100m to 500m.

12. What is meant by topology? Name some popular topologies.
Ans. Topology is the arrangement by which computers are connected with each other, either physically or
logically.
The popular topologies are:
(a) Bus or Linear Topology
(b) Ring Topology
(c) Star Topology
(d) Tree Topology
13. Why are fibre optic cables becoming popular?
Ans. Fibre optic transmission is becoming increasingly popular due to its noise resistance, low attenuation and
high bandwidth capabilities.
14. What factors should be taken into consideration while opting for a particular topology?
Ans. There are a number of factors which are to be considered:
(a) Cost
(b) Flexibility
(c) Reliability
15. What is a modem? What are the two types of modems?
Ans. Modem stands for modulator demodulator that converts analog signals to digital signals at the sender’s
end. It converts digital signals back to analog signals at the receiver’s end.
The two types of modems are: internal modem and external modem.
16. What is remote login? What is Telnet?
Ans. Remote login is the process of accessing a network from a remote place without actually being present
at the place of working. Telnet is an internet utility that lets us log on to a remote computer system. A
user is able to log in the system for sharing of files without being the actual user of that system.

17. Briefly explain FTP.
Ans. FTP stands for File Transfer Protocol. It is the standard mechanism provided by TCP/IP for copying a file
from one host to another. While sharing files from one system to another, we may encounter several
problems—two systems may have different directory structures, two systems may have different file-
Computer Networks
naming conventions, or two systems may have different ways to represent text and data. All these
problems are solved by FTP.

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