Short Questions Answer of Networking

Networking and Telecommunication

Short Answer Questions

1. List the different types of communication media with examples.

Ans: There are two types of communication media they are as follows:

 i) Guided media or Bounded media or wired communication:

Guided media are cable line through which data flow in a specified way.

Examples:

i) Open wire ii) Shielded twisted pair (STP) iii) Unshielded twisted pair (UTP)  iv) Coaxial cable

v) Fiber optics.

ii) Unguided media or Unbounded media or wireless communication:

In unguided communication media the data signal flow through the air.  They do not flow through the wire or cables.

Examples:

i) Radio frequency ii) Microwave iii) Satellite communication   iv) Infrared v) Bluetooth

 

2) Write the difference between guided and unguided media.

Guided media	Unguided media
It transmits the information over a closed path.	It Transmit the information through the air
It uses physical wire to transmit the data.	It does not use physical wire to transmit the data.
Example: Open wire, twisted pair cable, coaxial cable, fiber optic cable etc..	Example: Radio frequency, Microwave, Satellite, Infrared, Bluetooth etc..

3) What are the Advantages and disadvantages of computer network? 

Ans: Following are the advantages and disadvantages of computer network:

Advantages:

i) With the help of it we can share data and information between different computers.

ii) We can share computer devices such as printer, modem, disk storage and central service.

iii) We can easily send and receive the message

iv) We can share different software packages.

v) Data computing system is fastest in computer network.

Disadvantages:

i) Computer virus spreads each mostly through the network.

ii) Cyber crimes are originated from the computer network.

iii) With the help of computer network the anti social groups are able to launch their evil activities.

iv) It is little bit costly.

v) Lots of chances of technical problem in computer network.

vi) Special skilled manpower is required to operate computer network.

 

4) List the different services provided by computer network.

Ans: Network services are the things that a network can provide.

i) Print service

ii) File service

iii) Message service

iv) Application service

v) Database service

 

5) Write the different modes of transmission with examples.

Ans: There are two types of modes for Transmitting data from one device to another.

i) Simplex mode:

In this mode Transmission can take place in only one direction.

Examples: TV broadcasting, Radio, books, newspaper, letter etc.

ii) Half-duplex mode:

In this mode data can be Transmitted in both direction, but only one direction at  a time. 

Examples: walky-talky, wireless handset etc..

iii) Full-Duplex:

Full-duplex allows information to flow simultaneously in both directions on the transmission path. 

Example: Telephone, Smartphone

 

6) Write the differentiate between simplex and duplex data Transmission mode.

Simplex	Duplex
In it communication can        take place in only one direction	In it communication can take place in both direction.
It is also called unidirectional mode	It is also called bi-directional mode.
Example: Television, Radio, Newspaper etc..	Examples: Telephone, Wakie talkie etc..

 

7) Explain the different types of computer network.

Ans: Network can be classified according to the size, speed of data, distance covered, technology used, architecture used etc.. The most common classification of network is as follows:

i) Local Area Network (LAN):

This is the network within a very limited area like a single building, within a collage or extended up to a few km with wire. The media (wire) used in LAN must be same type and the protocol used in it is generally same. It is simpler and cheaper than any other networking system.

Features of LAN

i) LAN is owned privately by a single organization.

ii) LAN posses high data Transmission rate usually 1 to 100 MBPS.

iii) The connection between the workstation is short in distance.

iv) It is simpler and cheaper than other networking system

 

ii)  Metropolitans Area Network (MAN):

It extends up to a city or a larger geographical area. Many heterogeneous systems can be inter-connected in this system, different communication media can be adopted and different types of protocols can be used. Instead of using guided (wire) it can use unguided media (wireless media) too. Example of MAN is cable TV network.

Features of MAN:

i) It connects two or more LAN together.

ii) It covers metropolitan’s area.

iii) Uses cable or wireless connection.

 

iii) Wide Area Network (WAN):

 It is the network that is extended to a large area (throughout the world or even more) and communication is done through the satellite. It is the combination of many different types of LAN and MAN networks. The best example of WAN is Internet.

Features of WAN:

i) Owned by multiple organization.

ii) Covers large geographical area.

iii) Existence of the Internet.

iv) Slowest data communication rate that is below 1 MBPS

 

8) Explain the different types of network architecture.

Ans: The network architecture defines how the computer communication works in these networks.

Following are the different types of network architecture:

i) Centralized computing network:

In it, the main computer is called host computer. Here the workstation has no processing capability; they are just used for input/output operation. It is run with a powerful operating system called UNIX or Linux.

 

ii) Client/Server Network:

In it, computers are connected to a central device (server) and communication is done through it. The server is the main computer which gives services to the workstation. There are different types of server like print server, file server and network server etc.

 

iii)    Peer-to-Peer Network:

It is sometime called a work groups. In this network all the computers on the network have equal responsibilities. Each computer has access to at least some of the resource on all the computers. It is suitable for only small geographical; areas such as small room, building, school etc.

 

9) Write different types of topologies with advantages and disadvantages.   (SLC 2070)

Ans: Topology is the logical way of explaining how computers are connected to each other and show physically how they are linked. Generally, it is the caballing system in the network.

Topology can be classified on the following types:

i)   Bus Topology:

In it all the computers are connected to each other through common backbone cable or a bus. Usually this cable or bus is transmitted at either end and never be allowed to form a closed loop.

Advantages: (SEE 2073)

i) It is simple, reliable and easy to use.

ii) Low traffic network.

iii) If any of the computers in the network is down then also other computer can continue their work.

iv) It is more flexible because we can connect any number of computers by using a connector in the bus.

 Disadvantages:

i) Finding out fault and trouble shooting is hard.

ii) Heavy network traffic can slow a bus considerably.

iii) Limited to future addition of other devices.

iv) If problem occurs on the backbone "cable" the entire network will go down.

 

ii)  Star Topology:

 In it each node is usually connected by Ethernet cable or unshielded twisted pair(UTP). Each device in star topology has a point to point link to a central connecting device called "Hub".

Advantages: (SLC 2070)

i) Less expensive.

ii) Only need one link and one input/output port.

iii) Easy to find the failure link.

iv) All other link stays active even if one link fails to work.

Disadvantages:

i) Difficult to expand.

ii) Failure of the central (server) or the Hub makes whole system unavailable.

iii) Long cable length since each device is directly connected to the central hub.

iv) Many star networks require a device at the central point to rebroadcast or switch network traffic.

 

iii) Ring Topology:

In this topology, nodes are connected to each other in a closed loop by a single communication cable. Data Transfers in one direction from one node to another around the ring. It is also known as loop network.

Advantages:

i) No dependency on a central server, so all the computers are capable to act as a server  as well as client.

ii) Short cable connection which causes an increase in network reliability.

iii) Every computer has equal access facility to the resources.

iv) Since data travel in one direction, there is less chances of collision and there is less chance of data traffic.

 Disadvantages:

i) Any node failure causes network failure.

ii) Difficult to find out errors and trouble shooting.

iii) Non flexible because adding new computer on the network and removing existing computer is very hard.

 iv) Tree Topology:

 In this topology each device is connected to its own port or hub just like a star topology. Tree or "star of star" topology interconnects hubs at the top fashion so one hub at the top will be connected to many other hubs.

Advantages:

i) Easy to extend because it is divided into many sub units.

ii) Easy to add new nodes or branches.

iii) It is easy to detect and isolate defected node in the network.

 Disadvantages:

i) It is less reliable.

ii) Since the entire network depends on the root, the failure of the main root affects the entire network.

 

v) Mesh Topology:

It is a point to point connection between every device in network.

  

  Advantages:

i) Failure of a device does not affect the data transmission to the destination device.

ii) Easy to trouble shoot.

Disadvantages:

i) It is difficult to setup.

ii) It is more expensive than other topology.

iii) It is difficult to reconfigure.

 

10) Explain the following Network Transmission devices.

i) Media connecters:

Media connecter is attached directly to the medium itself and serves as the physical interface between cabling and network nodes. Some examples of media connecters are BNC- T connector, RJ-45 connector, DIX connector.

ii) Network Interface Card (NIC):

The NIC contains the electronic circuitry needed to ensure reliable communication between workstation and servers.

 iii) Repeaters:

A repeater accepts weak signals electrically regenerates them and then sends the messages on their way. There are two types of repeaters i) amplifiers ii) signal regenerating repeaters.

iv) Hub:

Hub is a device with multiple ports for connecting different computers on the network. There are three types of hub 

i) Passive hub 

ii) Active hub and 

iii) Intelligent hub.

 

11) What is Network Devices? Give some examples.

Ans: Internetworking hardware are the devices used to connect two or more networks from a single network. Following are the some examples of internetworking Transmission devices.

i) Bridge:

A bridge is a network connecting device, that interconnects two networks that use the same technology.

ii) Routers:

 A router is a network connecting device. Although a router can Transfers data between networks that use the same technology, but it commonly Transfer data between different technologies.

iii) Gateways:

A gateway is a network connecting device that interconnects two networks using different technologies

iv) Switch/Hub:

A switch is a device that provides a central connection points for cables from workstations, servers and peripherals.

 

12) Define the following Communication Transmission devices.

i) Modem:

Modem stands for modulator and demodulator. It is a device by which you may connect your computer to the ISP over the telephone. It is a device which converts analog data to digital and vice versa. There are two types of modem internal and external modem.

ii) Multiplexers: 

It allows sending multiple signals across signal Transmission medium.

iii) CSU/DSU:

 CSU (Channel Service Unit)/ DSU (Digital Service Unit) is used to connect digital computers to digital Transmission media instead of analog Transmission media.

 

13) Explain the different types of protocol.

Ans: Protocols are commonly agreed rules followed for interconnection and communication between computers in a network. Some common protocols are as follows:

TCP/IP:

TCP: Transmission Control Protocol is used for communication over a network.

Internet Protocol (IP) : IP is also working with TCP. It is an addressing Protocol.

HTTP: The full form of HTTP is "Hypertext Transfer Protocol." IT is used to transfer data over the www.

FTP: FTP Stands for "File Transfer Protocol." FTP is a is used to transfer data/files over the internet.

 SMTP: Full form of SMTP is Simple Mail Transfer Protocol." This is the protocol used for sending e-mail over the Internet.

POP: Short for Post Office Protocol, POP or POP mail is one of the most commonly used protocols used to receive e-mail on many e-mail clients.

 

14) Short notes on:

 i) Twisted pair cable:

Twisted pair cable are inexpensive media used in voice grade telephone lines. These twisted pair of cables can be used for low speed Transmission of signals but when line length goes beyond 100m, the error rates become high.

 

ii) Coaxial cable:

 Coaxial cables have wide band width and noise immunity. Coaxial cables are used to cover long distance telephone line. Its transmission speed is much higher than twisted pair of cables.

iii) Fiber optic cables:

 Fiber optic cables are made of plastic or glass fiber and gives high quality transmission of signals at very high speed. Fiber optic cable Transmission are not affected by electromagnetic interference. These can be used to communicate either analog or digital signals. These are most commonly used for point-to-point one way communication links.

iv) Radio-wave Transmission:

 Radio wave transmissions are used for communication between computers in inaccessible locations or for short range communications. The other benefit is the possibility of reaching rural and hilly area not covered by land telephone line.

 

v) Microwave Transmission:

Microwave Transmissions are used for wide band-width line of sight communication. But can’t pass obstacles like mountains.

 

vi) Satellite communication:

Satellite Transmissions are like microwave relay stations in the sky. Transponders on the satellite are used to receive amplify and retransmit signals sent from and earth station. A Transponder has a very large capacity and has a very large capacity and can handle more than 400 channels.

 

15) List the different types of modulation.

Ans:  Types of modulation:

i) Amplitude Modulation (AM)

ii) Frequency Modulation (FM)

iii) Phase Modulation (PM)

 

16) What is Server Computer? Write different types of servers.

Ans:    The most powerful computer in computer network is called server.  It has  higher processing and larger storage capacity compared to clients. Following are the various types of server:

i)       File server                                

ii)     Print server

iii)    Network server                        

iv)    communication server.

 

17) Define Clients and workstation.

i) Clients:

The clients are the computers on which users run applications. Clients are less powerful computers in comparison with servers.

ii) Workstation:

The individual personal computer used by network user is known as workstation.

 

18) Write short notes on:

 a) File server:

A file server is the host computer of LAN which manage the communication with other personal computer attached to it.

b) Print server:

The special printer which can receive and print data from any computer connected to LAN is known as print server.

c) Communication server:

The process of shared modems through LAN so that all the computer can communicate to each other’s is called communication server.

 

19)    What do you mean by Network operating system? List some examples of    Network operating system (NOS).

Ans: The group of programs that manage the process on the network is often called the network operating system.

Examples: Ms-Windows NT, Ms-Windows 2000,  Linux etc..

 

20) Define Star topology with figure. (SLC 2065, SEE 2072)

Ans: A topology where all computers or network devices are connected through a central device in the shape of a star is called Star topology.

 

21) Explain about network topology. Write any two advantages of computer networking. (SLC 2065 (supplementary)

Ans: The arrangement or connection pattern of computers or nodes and other devices of the network is called network topology. The two advantages of networking is as here under:

i) We can share peripherals devices such as printer, scanner modems and disk            storage.

ii) We can share data and information between different computers in network.

 

22) Give two differences between peer-to-peer and client server network                architecture. (SLC 2071)

Ans: Following are the difference between peer-to-peer and client server network architecture.

Peer-to-Peer	Client server
It has no central server	There are separate dedicated servers and clients in client/server network.
Not good for database application	It is good for database applications.

 

23) Explain, how the computer network reduces cost of operation?

Ans:   Computer network enables information sharing, hardware and software sharing and provides centralized administration and support. Thus, many resources like information, hardware and software or any other related items can be shared with each other without having buy new one. Therefore it is true that computer network reduces the cost of operation.

 

24) Define LAN topology and write any two types of LAN topology. (SLC 2068, 2072)

Ans: Physical layout of computers of Network or cabling structure of network is known as LAN topology.

Following are the two types of LAN topology

i) Bus Topology

ii) Star Topology

 

25) Write any four advantages of computer network. (SLC 2069)

Ans:    Four advantages of computer network are:

i) Sharing hardware and software resources.

ii) Sharing of resources reduces cost.

iii) Work can be shared among several computer users.

iv) Enables the central security system.

 

26)  Write the reasons of computer network.  (SLC Supp. 2070)

Ans: Following are the reasons of computer network.

i) Data sharing

ii) Communication

iii) Data security

iv) Sharing hardware and software

 

27) Give the importance of MODEM to the computer network. (SEE 2073 Supp.)

Ans: Modem stands for modulator and demodulator. It is a device by which you may connect your computer to the ISP over the telephone. It is a device which converts analog data to digital and vice versa.

 

28)  Write any two features of Guided media.    (SEE 2075 Regular)

Ans:    Any two features of Guided media are as follows.

i) Twisted-pair and coaxial cable use metallic (copper) conductors that accept and transport signals in the form of electric current.

ii) Optical fiber is a cable that accepts and transports signals in the form of light.

ii) Data transfer rate is high.

iii) Cover small geographical area.

 

29) What is Private Area Network (PAN) ? Write any two examples.

Ans:  A Personal Area Network (PAN) is the interconnection of information technology devices wihon a range of 10-15 meters of an individual person.

Following are the examples of PAN

i) TV remotes

ii) Smartphone’s

iii) Wireless printers

 

30) Write the advantages and disadvantages of PAN.

Ans:  Following are the advantages and disadvantages of PAN

Advantages:

i) No extra space requires

ii) Connect to many devices at  a time

iii) Easy to use

iv) Portable

v) Cost effective

Disadvantages :

i) Less distance range

ii) Slow data transfer

iii) Costly in terms of communication devices

 

31) List the components of Internet connection.

Ans: Components required for internet connection.

i)  Computer with web browser

ii)  ISP account

iii)  Router or  MODEM (necessary if you are using a telephone line to access the Internet)

iv) Connection (Dial-up, DSL, Cable, Satellite, Fiber)

 

32) Define internet. Write the different services of internet.

Ans: Internet is a large network of computers that connects to a backbone network.  It is a network of networks or it is also called mother of all networks.

Following are the different services of internet

i) WWW (Word Wide Web)

ii) E-mail

iii) Social media

iv) Chatting

v) e-commerce

vi) Online gaming

 

 33) What is modulation and demodulation?

Modulation:

Process of converting data into radio signals is known as modulation

Demodulation:

The process of receive radio wave signals into original message signal is known as demodulation.

 34) Define intranet and extranet.

Intranet:

A private network which can be accessed by authorized users only is known as intranet.

Extranet:

Extranet is a local network accessible to specific outside users or businesses, but still inaccessible to the general public.

 

35) Write the advantages and disadvantages of e-mail.
   Advantages:

i) Cheapest and fastest means of communication.

ii) It is more reliable than other means.

iii) It can be used from any part of the word at any time.

iv) Even picture can be sent along with text.

v) Single mail can be sent to different mail address.

Disadvantages:

i) E-mail is being the main route of spread computer virus.

ii) The lightest error in the e-mail address or a failure in one of the links between the sender and receiver is enough to prevent a delivery.

iii) The recipient may or may not read the mail on time.

iv)  E-mail is depends on the electricity and telephone system.

 

36) What is Internet? Write the name of any two e-commerce sites.  (SLC 2069)

Ans: Internet can be defined as network of networks. Following are the two commerce sites    are:  

i) www.hamrobajar.com ii) www.daraz.com

 

37) Write the difference between postal service and e-mail.

Postal Service	Email
Slow mean of communication	Fast means of communication
Only specific type of handwriting and style is used.	Special kinds of font style and graphics can be used
Traditional way of exchanging information	Digital way of exchanging information.
The postal service has an address they deliver to no matter what the recipient’s name is.	In e-mail you have to write e-mail address correctly if not mail will not be sent.
It requires packaging	It does not require packaging
Less secured	More secured

 

38) Write any four advantages of Internet. (SEE 2075 Regular) 

Ans: Following are the advantages and disadvantages of internet.

Advantages:

i) Easy to connect with people.

ii) Online shopping

iii) We can do work and learning from home.

iv) Online banking

v) Entertainment

vi) Social network

Disadvantages:

i) Internet addiction

ii) Access to wrong information

iii) Theft of personal information

iv) Malware and Virus threat

v) Online threading or harassment

vi) Health problem

 

39) Define the following basic terms related to Internet:

Website:

Website is the location of several web pages created by any business organization / university to provide their information in the internet.

Example: www.avndhn.edu.np,           www.nepalnews.com

 URL:

The unique address of the webpage is known as URL (Uniform Resource Locator)

URL= http://www.avndhngpj.edu.np

      

Webpage: 

Internet consists of a huge collection of documents with lots of information called webpage

OR

It is a collection of information that is stored in the website.

 Browser: 

Browser is client software that allows the user to display and interact with a webpage. Example: Internet explorer, Mozilla Firefox, Netscape navigator, Opera, Microsoft Edge etc..

 

WWW:

It is a service that is interconnected through hypertext. It provides link in the     web documents.

 

Web Server:

A site on which web pages are stored is known as web server. It is a program that responds to request from web browser to relative resources.

 

Domain Name:

It is the name of a specific internet area controlled by any organization,     company or government.

HTTP: 

It is a protocol that web browser and web service use to communicate with each other.

 

FTP: 

It is a protocol that allows a user or host to access and Transfer files to another host over a network.

 

Chat:

It is a program that allows user on the internet to communicate with each other by typing in real time.

 

Search Engine: 

It is an interactive tool to help people to locate information via www.  Example www.google.com, www. yahoo.com, www.excile.com etc.. Some popular search engines are:

i) Yahoo ii) Google iii) infoseek iv) inference v) Bing etc..

 

Upload: 

It refers to copying files or documents or programs or data from user computer to the Internet.

 

Download: 

It refers to copying files, documents or programs or data from the internet server to the user's computer.

 

Internet Service Provider(ISP):

 An  ISP is an organization that maintains a getaway computer having direct connectivity to the Internet access facility to other users by allowing them to connect with their personal computers to its own gateway computer by using a modem

40) What is a computer network? Enlist any two advantages of it. (Specification grid 2077)

Ans: Computer networking is interconnectionaninterconnectioThe advantages of different computing devices are that can exchange data and share resources with each other.

Advantages of computer network are as here under.

i)  Sharing computer resources. (Hardware and software) 

ii) Fast means of communication.

iii) Centralized administration

iv) Large storage capacity

 

39) What is computer network? Write any two advantages of it. (SEE 2078)

Ans: Interconnection of two or more than two computer with the help of wire or wireless is known as computer network.

Advantages of computer network:

i) Easy to share hardware and software.

ii) Data backup and security is possible.

 

40) What is a computer network? List any two importance of it. (SEE Grade Promotion Exam 2078)

Ans: Interconnection of two or more than two computers by using wire or wireless is known as a computer network.

Two importance of computer network are as follows:

i) Hardware and software sharing.

ii) It is fast and cheap means of communication.

 

41) What is network topology? List any two types of network topology. (SEE 2079)

Ans: Network topology refers to the physical or logical arrangement of devices on a computer network and how they are interconnected.
Following are the two types of network topology.
i) Bus topology
ii) Star topology