CBSE Class 12 Computer Science Computer Networks Worksheet Set C

Short Answer Type 

Question. Your friend wishes to install a wireless network in his office. Explain him the difference between guided and unguided media.
Answer. Guided media uses cables to connect computers, whereas unguided media uses waves

Question. What are Protocols? Name the protocol used to transfer a file from one device to the other.
Answer. Protocols are set of rules that are followed while transmitting data through a computer network. Protocols determines how to data can be moved securely from a source device to a destination device. The protocol used for transferring a file from one device to another is the File Transfer Protocol (FTP)

Question. Define communication channel.
Answer. A communication channel is the medium through which data is moved from the source to destination. The communication channel can be either wired or wireless. Wired communication channel is also called guided medium while wireless communication channel is also called unguided medium.

Question. What do you mean by an IP Address? Give an example for IP Address.
Answer. An IP Address is a numerical address that uniquely identifies every device connected to a network or internet. The user’s physical location can be tracked by using an IP Address. IP V4 (IP Version 4) is a popular version of IP Address. IP Address (in IP V4) consists of four set of numbers separated by a dot. These numbers can range from 0 to 255. An example IP Address format is given below: 192.158.12.38

Question. Differentiate between Circuit Switching and Packet Switching.
Answer. In Circuit Switching a physical connection between the sender and the receiver is set up first. Then, through that physical link, the complete message is communicated continuously. After completion of the transmission, the physical connection is terminated.
In Packet Switching, the message is split into small units called packets. Then these packets are passed from source to destination simultaneously through different routes in the network. As the flow of packets are asynchronous, sequence numbers are assigned to each packet to facilitate re-ordering of packets at the destination.

Question. Define the following: a. Bandwidth b. Data rate
Answer. Bandwidth: It is the range of frequencies that can be carried through a communication channel. The bandwidth of a channel determines its capacity. It is the difference between the highest and lowest frequencies that can be carried through the channel. The unit of Bandwidth is Hertz (Hz).
Data transfer rate: It is the amount of data moved through a communication channel per unit time. The units of Data transfer rate are Bits per second (Bps), Kilobits per second (Kbps) , Megabits per second (Mbps) or Gigabits per second (Gbps).

Question. Explain the components of data communication.
Answer. The components of data communication are: Sender, Receiver, Message, Communication Medium and Protocols.
Sender: The device which sends data through a network is called sender or source.
Receiver: The device which receives data through a network is called receiver or destination. Message: The data that is communicated between the source and the destination is called message.
Communication channel: The medium through which the data is carried from the source to destination is called a communication medium.
Protocols: The set of rules followed while communicating data over a network are called Protocols.

Question. What are the advantages of Packet switching over Circuit switching.
Answer. In Packet Switching the communication channel is utilized completely whenever it is free. Where as in Circuit Switching, once the connection is assigned for a particular communication, the entire channel cannot be used for other data transmissions even if the channel is free. Data packets moves simultaneously through different paths in a Packet Switched network, making the transmission quick and easy. But in the case of Circuit Switched network, there is a delay in setting up a physical connection between the source and destination before communicating the actual message. Packet Switching is cost effective compared to Circuit Switching as there is no need to set up a connection between the communicating parties every time before the actual communication.

Question. Explain why Circuit Switching is not cost effective compared to Packet Switching?
Answer. The Circuit Switching is not cost effective like Packet Switching because, in Circuit Switching, every time there is a need to set up a connection between the sender and the receiver before communicating the message.

Question. Explain how an IP Address become helpful in investigating cyber-crimes.
Answer. IP address can be used to trace the physical location of a user connected to a network. By this many cyber crime can be investigated and traced out efficiently tracking the exact location from where the cybercrime is carried out.

Question. Why Protocols are needed in the case of Data Communication?
Answer. The communicating devices may be in different geographical areas. The speed of these devices may be different. Also, the data transfer rates of different networks may be different. These complexities make it necessary to have a common set of rules i.e., Protocols to ensure the secure communication of data

Question. What is the difference between World Wide Web & Internet?
Answer. Internet means interconnected networks that spread all over the world (i.e. the physical infrastructure), while WWW means the information’s (available in the form of webpages) that can be accessed through internet.

Question. What is a protocol, give some examples?
Answer. Protocols are set of rules that are followed while transmitting data through a computer network. Protocols determines how to data can be moved securely from a source device to a destination device. The protocol used for transferring a file from one device to another is the File Transfer Protocol (FTP)

Question. What is the difference between E-mail and chat?
Answer. n order to chat, you need to have an account on the same service as the person you are chatting with. e.g. 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. 15. What are cookies? Cookies are files stored temporarily on www browser’s computer, which allow the www server to store persistent information associated with browsing user on user’s system.

Question. What is the difference between domain name and IP address?
Answer. IP addresses look like this: 192.168.12.134.
Domain names look like this: “www.google.com”
Domain names are easier for us to remember and use, while computers are quite handy with numbers. Thus, we use DNS (Domain Naming System) to translate domain names into the IP addresses.
IP address is a unique identifier for a computer or device on internet. A domain name (website name) is a name that identifies one or more IP addresses (when hosted at different servers for load balancing).

Question. Give one suitable example of each URL and domain name?
Answer. URL: https://kvsangathan.nic.in/hq-gyan-kosh Domain name: kvsangathan.nic.in

Question. Differentiate between XML and HTML.
Answer. XML was designed to describe data and to focus on what data is.
HTML was designed to display data and to focus on how data looks. HTML is about displaying information while XML is about describing information.

Question. Distinguish between website and web browser.
Answer. Website:- It is a collection of inter-linked web pages stored in a server.
Web Browser:- It is a software application for retrieving, presenting and traversing through information resources in the form of web pages available on the World Wide Web.

Question. Differentiate between communication using Optical Fiber and Ethernet Cable in context of wired medium of communication technologies.
Answer. Optical Fibre - Very Fast - Expensive - Immune to electromagnetic interference Ethernet Cable - - Slower as compared to Optical Fiber - Less Expensive as compared to Optical Fiber - prone to electromagnetic interference

Question. Ravi was trying to log-in to his internet-banking account. He noticed that the URL of the net banking starts with 'https'. The 's' in 'https' stands for _______
(i) Simple 0(ii) Smart (iii) Secure (iv) Strength
Answer. (iii) Secure

Question. What is mean by the homepage of a website?
Answer. The default (first) page of a website is called a Homepage.

Question. What is the significance of the URL?
Answer. URL specifies unique address of each document on the internet.

Question. Which of the following is not a network protocol?
(i) HTML (ii) HTTP (iii) SMTP (iv) FTP
Answer. 
(i) HTML
Internet Protocols for communication over the Internet, the communicating devices must follow certain rules.
These rules are called Internet protocols.
For email communication, we use SMTP and POP. For communication between browser and server HTTP and HTTPS protocols are used.
We can use TELNET to access services available on a remote computer.

Question. Which of the following internet protocols provides secure data transmission between server and browser with the help of encryption.
a) HTTP
b) HTTPS
c) TELNET
d) ARPANET
Answer. B

Question. Devanand, a student of Class XII, is not able to understand the difference between web client and web-server. Help him in understanding the same by explaining their role and giving suitable example of each.
Answer. Web-Client: An application that requests for services from a webserver. Example: Web Browsers, Chatting Applications
Web-Server: Web-server is a software (or any dedicated computer running this software) that serves the request made by web-clients. Example: Apache Server.

Question. Write the full form of Cc and Bcc (used in email communication). Explain the difference between them.
Answer. Cc : Carbon Copy: every recipient can check who else has received the mail.
Bcc : Blind Carbon Copy: no recipient can check who else has received the mail.

Question.Define Internet and write its two uses in our daily life. How is it different from the World Wide Web (WWW).
Answer. The Internet is a worldwide network that links many smaller computer-networks.
Uses of the Internet 1. E-learning 2. E-commerce
The difference between the internet and www: Internet means interconnected networks that spread all over the world (i.e. the physical infrastructure), while WWW means the information’s (available in the form of webpages) that can be accessed through internet.

Question. Web _________ is a software used to view web pages.
Answer. Web Browser

Question. In a network, _____________ is a computer that provides data and resources to other computers.
Answer. Server

Question. How is a website and a webpage related?
Answer. A website is a collection of interlinked webpages.

Question. Microsoft Edge, Apple Safari are examples for __________________
Answer. Web Browsers

Question. What is the use of a server in a computer network?
Answer. Role of server is to serve various clients (sharing data or resources among multiple clients)

Question. Among the following service available on the World Wide Web are?
i) Email ii) HTML iii) XML iv) Video conferencing
(a) (i) and (ii)
(b) (i) and (iv)
(c) (ii) and (iii)
(d) None of the above
Answer. B

Question. HTML and XML are _______________
(a) Programming Languages
(b) Scripting Languages
(c) Mark-up Languages
(d) None of the above
Answer. C

Question. XML uses _____________
(a) User defined tags
(b) Predefined Tags
(c) Both user defined and predefined tags
(d) None of the above
Answer. A

Question. XML was not designed to ____________________
(a) store the data
(b) present the data
(c) carry the data
(d) both a & c
Answer. B

Question. Which of the following will you suggest to establish the online face to face communication between the people in the Regional Office Ernakulum and Delhi Headquarter?
(a) Cable TV
(b) Email
(c) Text chat
(d) Video Conferencing
Answer. D

Question. What kind of data gets stored in cookies and how is it useful?
Answer. Cookies can store a wide range of information, including personally identifiable information (such as your name, home address, email address, or telephone number). Cookies often store your settings for a website, such as your preferred language or location. When you return to the site, browser sends back the cookies that belong to the site. This allows the site to present you with information customized to fit your needs.

Question. What do the following top level domains signify?
(a) .com
(b) .org
Answer. (a) .com - commercial (b) .org - organization

Question.“With XML you invent your own tags”, Explain this statement with the help of example.
Answer. XML tags are created by the user as there are no standard tags.
Ex : <name>Nayana<name>

Question.Define Domain Name Resolution?
Answer. The process of converting domain names (website names) into corresponding IP address with the help of DNS servers is called domain name resolution.

Question.  ____________ tags are case sensitive and _____________ tags are not case sensitive.
(a) HTML, XML
(b) HTTP, XML
(c) XML, HTTP
(d) XML,HTML
Answer. D

Question. Which of the following is not a web browser ?
(a) Google Chrome
(b) Internet Explorer
(c) Mozilla Firefox
(d) Photoshop
Answer. D

Question. Which protocol helps us to browse through web pages using internet browsers?
Answer. HTTP - Hyper Text Transfer Protocol

Question. Name any one internet browser.
Answer. Google Chrome or any other valid browser name

Question. XML stands for
(A) Xtra Markup Language
(B) Extensible Markup Language
(C) Extensible Marking Language
(D) Extensive Marked Language
Answer. B

Question. We can upload a file to a web server using a protocol called __________.
(A) FPT
(B) IP
(C) TCP
(D) FTP
Answer. D

Question. _____________ delivers the requested web page to web browser.
Answer. Web Server