Communication Open Source Concept | class 12th | Important question Computer Science

Important Questions for Class 12 Computer Science – Communication Technologies

Question 1:
Give two examples of PAN and LAN type of networks. Delhi 2016
Аnswer:
Two examples of PAN type of networks 3.
are as follows:

1. Upload the photo from your cell phone to your desktop computer.
2. Watch movies from an online streaming service to your TV.

Two examples of LAN type of networks
are as follows:

1. Small office or a Internet cafe.
2. Two or more computers connected in few distances.

Question 2:
Which protocol helps us to browse through Web pages using Internet browsers? Name any one Internet browser. Delhi 2016
Аnswer:
Protocol → HyperText Transfer Protocol A.
(HTTP)
Internet Browser → Google Chrome

Question 3:
Write two advantages of 4G over 3G Mobile Telecommunication Technologies in terms of speed and services. Delhi 2016
Аnswer:
Two advantages of 4G over 3G mobile telecommunication technologies are as follows:

Question 4:
Write two characteristics of Web 2.0. Delhi 2016; All India 2016
Аnswer:
Characteristics of Web 2.0 are as follows:

1. Free classification of information
2. User as a contributor

Question 5:
What is the basic difference between Trojan Horse and Computer Worm? Delhi 2016; All India 2016
Аnswer:
Computer worms are programs that replicate themselves from system to system without the use of a host file, while Trojan horses are impostor files that claim to be something desirable but, in fact are malicious.

Question 6:
Categorise the following under Client Side and Server Side script category:

1. VBScript
2. ASP
3. JSP
4. JavaScript
   All India 2016: Delhi 2016

Аnswer:
Client side scripting languages are as follows: JavaScript, VBScript
Server side scripting languages are as follows: ASP, JSP

Question 7:
Differentiate between PAN and LAN types of networks. All India 2016
Аnswer:
PAN network is a computer network organised around an individual person, while LAN network is a privately owned networks within a single building or campus upto a few kilometres in distance.

Question 8:
Which protocol helps us to transfer files to and from a remote computer? All India 2016
Аnswer:
Protocol → File Transfer Protocol ( FTP )

Question 9:
Write two advantages of 3G over 2G Mobile Telecommunication Technologies in terms of speed and services. All India 2016
Аnswer:
Two advantages of 3G over 2G Mobile Telecommunication Technologies are as follows:

1. The downloading and uploading speeds available in 3G technologies are upto 21 Mbps and 5.7 Mbps respectively while in 2G technologies the downloading and uploading speeds are upto 236 Kbps.
2. The services like mobile TV, video transfer and GPS systems are the additional features of 3G technology that are not available with 2G technologies.

Question 10:
Illustrate the layout for connecting
5 computers in a bus and a star topology of networks. All India 2015: Delhi 2015
Аnswer:

Question 11:
What is a spam mail? Delhi 2015
Аnswer:
Spam Mail is flooding on the Internet with many copies of the same meaning, in an attempt to force the message on people who would not otherwise choose to receive it.

Question 12:
Differentiate between FTP and HTTP.  Delhi 2015
or
What is the difference between HTTP and FTP? All India 2013
Аnswer:
FTP is a protocol used to upload files from a workstation to a FTP server or download files from a FTP server to a workstation while, HTTP is a protocol used to transfer files from a Web server onto a browser in order to view a Web page that is on the Internet.

Question 13:
Out of the following, which is the fastest

1. wired and
2. wireless medium of communication? Infrared, Coaxial Cable, Ethernet Cable, Microwave, Optical Fiber.
   All India 2015: Delhi 2015

Аnswer:

1. Wired-Optical Fiber
2. Wireless-Infrared

Question 14:
What is Worm? How is it removed? Delhi 2015
Аnswer:
A computer worm is a stand alone malware computer program that replicates itself in order to spread to other computers.
Worms can be removed by installing antivirus.

Question 15:
Out of the following, which one comes under cyber crime?

1. Stealing away a brand new computer from a showroom.
2. Getting in someone’s social networking account without his consent and posting pictures on his behalf to harass him.
3. Secretly copying files from’ server of a call center and selling it to the order organisation.
4. Viewing sites on a internal browser. Delhi 2015

Аnswer:
(ii) Getting in someone’s social networking account without his consent and posting pictures on his behalf to harass him.

Question 16:
What kind of data gets stored in cookies and how is it useful? All India 2015
Аnswer:
Cookies contain random alphanumeric text characters, which are determined by the specific Website that created that cookie. It helps you to access a site faster and more efficiently.

Question 17:
Differentiate between packet switching over message switching. All India 2015
or
Differentiate between packet switching and message switching technique in network communication? Delhi 2011
Аnswer:
In message switching, large storage space is required at each node to buffer the complete message blocks. On the other hand in packet switching, messages are divided into subset of equal length, which are generated in the source node and reassembled to get back the initial complete message in destination node.

Question 18:
What is Trojan Horse? All India 2015
Аnswer:
Trojan Horse It is a type of malware designed to provide unauthorised, remote access to a user’s computer. Trojan horses do not have the ability to replicate themselves. They can lead to viruses being installed on a machine since they allow the computer to be controlled by the trojan creator.

Question 19:
Write one characteristic each for 2G and 3G mobile technologies. Delhi 2014
Аnswer:
Characteristic of 2G mobile technology is that it has introduced data services for mobile, starting with text messaging.
Characteristic of 3G mobile technology is that it is faster than 2G and supports video calling.

Question 20:
What is the difference between video conferencing and chat? Delhi 2014
Аnswer:
Chat generally involves one-to-one communication. On the other hand, video conferencing means more than two persons are involved in a discussion.

Question 21:
Expand the following:

1. GPRS
2. CDMA
3. GSM Delhi 2014: All India 2014

or

Expand the following abbreviation:

1. GSM
2. CDMA Delhi 2009

Аnswer:

1. GPRS General Packet Radio Services.
2. CDMA Code Division Multiple Access.
3. GSM Global System for Mobile Communication.

Question 22:
Write two characteristics of Wi-Fi.  All India 2014
Аnswer:
Characteristics of Wi-Fi are as follows:

1. It is a wireless solution for getting connected to the Internet.
2. It is handly as well as availably throughout the journey.

Question 23:
What is the difference between E-mail and chat? All India 2014; Delhi 2013C
Аnswer:
In order to chat, you need have an account on the same service as the person you are chatting with.
On the other hand, in case of e-mail, it is not necessary, i.e. you can have an account from any provider and you can establish your own.

Question 24:
Which type of network (out of LAN, PAN and MAN) is formed, when you connect two mobiles using bluetooth to transfer a picture file? Delhi 2014
or
Which type of network (out of LAN, PAN and MAN) is formed, when you connect two mobiles using bluetooth to transfer a video.  All India 2014
Аnswer:
When two mobiles are connected using bluetooth to transfer a picture file, a PAN (Personal Area Network) is created.

Question 25:
Which of the following crime(s) does not come under cybercrime?

1. Copying some important data from a computer without taking permission from the owner of the data.
2. Stealing keyboard and mouse from a shop.
3. Getting into unknown person’s social networking account and start messaging on his behalf. All India 2013

Аnswer:
(ii) Stealing keyboard and mouse from a shop.

Question 26:
What is the difference between domain name and IP address? Delhi 2013
Аnswer:
IP address is an identifier for a computer or device on a TCP/IP network, e.g. 1.160.10.240 could be an IP address. Whereas, a domain name is a name that identifies one or more IP addresses, e.g. the domain name microsoft.com represents about a dozen IP addresses.

Question 27:
Write two advantages of using an optical fibre cable over an Ethernet cable to connect two service stations, which are 190 m away from each other. Delhi 2013
or
Write two advantages of using an optical fibre cable over an Ethernet cable to connect two service stations, which are 190 —> 200 m away from each other.  All India 2013
Аnswer:
Two advantages of using optical fibre cable over an Ethernet cable are as follows:

1. Low power because signals in optical fibres degrade less, low-power transmitters can be used.
2. Digital Signals Optical fibres are ideally suited for carrying digital information, which is especially useful in computer networks.

Question 28:
What is the difference between packet switching and circuit switching techniques? All India 2013 (C)
Аnswer:
(i) circuit Switching In this, firstly complete
physical connection between two computers is established. After that data are transmitted from the source computer to the destination computer.
e.g. In telephone call, circuit switching is used.
Packet Switching In this, there is a fixed size of packet and data packets are stored in the main memory.
This improves the access time.

Question 29:
Expand the following abbreviations:
(a) HTTP (b) VoIP
All India 2013
Аnswer:
(a) HTTP: HyperText Transfer Protocol
(b) VoIP: Voice over Internet Protocol

Question 30:
Which of the following crime(s) is/are covered under cybercrime?

1. Stealing brand new hard disk from a shop.
2. Getting unknown person’s social networking account and start messaging on his behalf.
3. Copying some important data from a computer without taking permission from the owner of the data. Delhi 2013

Аnswer:
(ii) Getting into unknown person’s social networking account and start messaging on this behalf.

Question 31:
What out of the following, you will use to have an audio visual chat with an expert sitting in a far away place to fix-up technical issue?

1. E-mail
2. VoIP
3. FTP Delhi: All India 2012

Аnswer:
(ii) VoIP