Computer Science · Chapter 01

116 solved questions

Computer Network And Telecommunication

Every question in this chapter, answered and explained — step-by-step solutions drawn live from the chapter library across 7 question sections.

Objective Questions - Mark the Correct Option20 Write the Full Form of26 Write the Tech Terms for the Following20 Descriptive Questions - Answer the Following Briefly22 Descriptive Questions - Answer Comprehensively18 Case Study and Application-Based Questions4 Extra Revision Questions6

Objective Questions - Mark the Correct Option

1Textbookcs1-q1

Which of the following topologies uses a central hub or switch? (i) Ring topology (ii) Star topology (iii) Bus topology (iv) Mesh topology

Ans.(ii) Star topology - all devices connect to a central hub or switch.

2Textbookcs1-q2

What type of IP address uses 128 bits? (i) IPv1 (ii) IPv4 (iii) IPv6 (iv) IPX

Ans.(iii) IPv6 - uses a 128-bit address system.

3Textbookcs1-q3

Which wireless media is best for identifying and tracking items? (i) Wi-Fi (ii) RFID (iii) Bluetooth (iv) Infrared

Ans.(ii) RFID - Radio Frequency Identification is designed for identifying and tracking objects using electronic tags.

4Textbookcs1-q4

What is the main purpose of a firewall in a network? (i) Increase speed (ii) Store data (iii) Protect against unauthorized access (iv) Reduce signal interference

Ans.(iii) Protect against unauthorized access - a firewall blocks harmful data and controls what can enter or leave a network.

5Textbookcs1-q5

What is the shape of a ring topology? (i) Star (ii) Linear (iii) Loop (iv) Mesh

Ans.(iii) Loop - in a ring topology, devices form a closed loop where each device connects to exactly two others.

6Textbookcs1-q6

What do you call the technology that allows mobile phones to share internet with laptops? (i) Router (ii) Access point (iii) Repeater (iv) Mobile hotspot

Ans.(iv) Mobile hotspot - a feature that lets a phone share its internet connection with other devices using Wi-Fi.

7Textbookcs1-q7

What device helps link networks across cities and countries? (i) Switch (ii) Router (iii) Hub (iv) Bridge

Ans.(ii) Router - routers connect different networks together and forward data between them, including across cities and countries.

8Textbookcs1-q8

Which generation of mobile technology supports self-driving cars and IoT? (i) 3G (ii) 4G (iii) 5G (iv) 2G

Ans.(iii) 5G - offers ultra-high speed, very low latency, and supports smart cities, driverless cars, and IoT.

9Textbookcs1-q9

Which communication channel is used in wired networks? (i) Optical fiber (ii) Radio waves (iii) Microwaves (iv) Bluetooth

Ans.(i) Optical fiber - a wired (cable-based) communication channel; radio waves, microwaves, and Bluetooth are wireless.

10Textbookcs1-q10

Which device reduces network collisions and works in full duplex mode? (i) Hub (ii) Switch (iii) Repeater (iv) Modem

Ans.(ii) Switch - it sends data only to the intended device (reducing collisions) and works in full-duplex mode.

11Textbookcs1-q11

What is the main function of a repeater? (i) Boost weak signals (ii) Convert signals (iii) Filter data (iv) Block interference

Ans.(i) Boost weak signals - a repeater amplifies weak or faded signals and retransmits them.

12Textbookcs1-q12

Which is not a feature of LAN? (i) Covers small area (ii) Uses switches or hubs (iii) Needs satellites (iv) High-speed transfer

Ans.(iii) Needs satellites - LAN is a small, local network and does not need satellites; satellites are used for very long-distance communication.

13Textbookcs1-q13

What unit is used to measure bandwidth? (i) Hertz (ii) Bits per second (bps) (iii) Kilometers (iv) Joules

Ans.(ii) Bits per second (bps) - bandwidth is measured in bps, such as Kbps, Mbps, and Gbps.

14Textbookcs1-q14

What is the smallest type of network for personal gadgets? (i) LAN (ii) PAN (iii) MAN (iv) WAN

Ans.(ii) PAN (Personal Area Network) - the smallest network, covering about 10 meters, for personal gadgets.

15Textbookcs1-q15

What helps in transmitting light within an optical fiber? (i) Copper (ii) Total internal reflection (iii) Electricity (iv) Infrared

Ans.(ii) Total internal reflection - this principle keeps light pulses bouncing within the core of the optical fiber.

16Textbookcs1-q16

Which topology fails completely if the backbone cable breaks? (i) Star (ii) Ring (iii) Bus (iv) Hybrid

Ans.(iii) Bus - since all devices share a single backbone cable, if it breaks, the entire network fails.

17Textbookcs1-q17

Which device converts signals between copper and fiber cables? (i) Repeater (ii) Bridge (iii) Media converter (iv) Hub

Ans.(iii) Media converter - converts signals between copper cable and fiber optic cable.

18Textbookcs1-q18

Which of the following is not used in wireless media? (i) Radio waves (ii) Infrared (iii) Coaxial cable (iv) Wi-Fi

Ans.(iii) Coaxial cable - this is a wired media; radio waves, infrared, and Wi-Fi are wireless media.

19Textbookcs1-q19

What layer does the hub operate on? (i) Physical layer (ii) Network layer (iii) Data link layer (iv) Transport layer

Ans.(i) Physical layer - a hub operates on the physical layer of the OSI model.

20Textbookcs1-q20

Which of the following is an example of intranet use? (i) Emailing a client (ii) Sharing policies within an organization (iii) Posting on Facebook (iv) Accessing public websites

Ans.(ii) Sharing policies within an organization - this uses the organization's private internal network (intranet); the other options involve the public internet.

Write the Full Form of

1Textbookcs2-q1

OSI

Ans.Open Systems Interconnection

2Textbookcs2-q2

MAN

Ans.Metropolitan Area Network

3Textbookcs2-q3

LAN

Ans.Local Area Network

4Textbookcs2-q4

PAN

Ans.Personal Area Network

5Textbookcs2-q5

WAN

Ans.Wide Area Network

6Textbookcs2-q6

RJ45

Ans.Registered Jack 45

7Textbookcs2-q7

STP

Ans.Shielded Twisted Pair

8Textbookcs2-q8

UTP

Ans.Unshielded Twisted Pair

9Textbookcs2-q9

RFID

Ans.Radio Frequency Identification

10Textbookcs2-q10

DSL

Ans.Digital Subscriber Line

11Textbookcs2-q11

Mbps

Ans.Megabits per second

12Textbookcs2-q12

Ans.Internet Protocol

13Textbookcs2-q13

IPv4

Ans.Internet Protocol version 4

14Textbookcs2-q14

IPv6

Ans.Internet Protocol version 6

15Textbookcs2-q15

WWW

Ans.World Wide Web

16Textbookcs2-q16

USB

Ans.Universal Serial Bus

17Textbookcs2-q17

NIC

Ans.Network Interface Card

18Textbookcs2-q18

ISP

Ans.Internet Service Provider

19Textbookcs2-q19

GPS

Ans.Global Positioning System

20Textbookcs2-q20

TCP/IP

Ans.Transmission Control Protocol/Internet Protocol

21Textbookcs2-q21

VoIP

Ans.Voice over Internet Protocol

22Textbookcs2-q22

FTP

Ans.File Transfer Protocol

23Textbookcs2-q23

IoT

Ans.Internet of Things

24Textbookcs2-q24

Wi-Fi

Ans.Wireless Fidelity

25Textbookcs2-q25

MAC

Ans.Media Access Control

26Textbookcs2-q26

Ans.Television

Write the Tech Terms for the Following

1Textbookcs3-q1

A device that amplifies weak signals and retransmits them to improve the coverage of the network.

Ans.Repeater

2Textbookcs3-q2

A protocol suite used for communication over the internet and similar networks.

Ans.TCP/IP (Transmission Control Protocol/Internet Protocol)

3Textbookcs3-q3

A private network system used only within an organization.

Ans.Intranet

4Textbookcs3-q4

A type of cable made of thin glass strands used to transmit data as light.

Ans.Optical fiber (cable)

5Textbookcs3-q5

A network device that connects different networks and selects the best data path.

Ans.Router

6Textbookcs3-q6

The physical path or medium through which data travels from one device to another.

Ans.Communication channel/media (communication media)

7Textbookcs3-q7

A form of network that connects devices within a city, larger than a LAN.

Ans.MAN (Metropolitan Area Network)

8Textbookcs3-q8

An address system that uses 32 bits and is separated by dots.

Ans.IPv4

9Textbookcs3-q9

The maximum data transfer speed or capacity of a network connection.

Ans.Bandwidth

10Textbookcs3-q10

The smallest network used to connect personal devices over short distances.

Ans.PAN (Personal Area Network)

11Textbookcs3-q11

A type of wireless communication that uses very short-range radio signals, often for headsets and phones.

Ans.Bluetooth

12Textbookcs3-q12

The type of topology where each device is connected to exactly two other devices.

Ans.Ring topology

13Textbookcs3-q13

A wireless signal type that is often blocked by walls and works only over very short distances, like remote controls.

Ans.Infrared

14Textbookcs3-q14

A smart device that connects computers on a LAN and sends data only to the correct destination.

Ans.Switch

15Textbookcs3-q15

The arrangement or layout of devices and cables in a computer network.

Ans.Network topology

16Textbookcs3-q16

An orbit that allows a satellite to stay fixed above a specific location on Earth.

Ans.Geostationary orbit

17Textbookcs3-q17

A device that allows computers with copper cables to connect to fiber optic networks.

Ans.Media converter

18Textbookcs3-q18

The process of sending the same data to all devices on a network.

Ans.Broadcasting

19Textbookcs3-q19

A connection method that uses telephone lines and is very slow compared to modern standards.

Ans.Dial-up (dial-up internet connection)

20Textbookcs3-q20

A form of network architecture where all devices can serve each other without a central server.

Ans.Peer-to-Peer (P2P) architecture

Descriptive Questions - Answer the Following Briefly

1Textbookcs4-q1

What is telecommunication? Give two examples of telecommunication.

Ans.Telecommunication is the passing of information over a distance via electronic devices such as a telephone, cell phone, or computer, through wired or wireless data transmission media, without being physically present. Examples: (1) Making a phone call to a friend, (2) Sending an email.

2Textbookcs4-q2

What is broadband? State two differences between broadband and dial-up technology.

Ans.Broadband is a high-speed, continuous internet connection technology that can carry huge amounts of data quickly over wired or wireless networks. Two differences: (1) Broadband is much faster than dial-up, while dial-up is slow, (2) Broadband allows continuous internet access without blocking the phone line, while dial-up uses the telephone line and cannot be used for calls at the same time.

3Textbookcs4-q3

What is bandwidth? How is it measured?

Ans.Bandwidth is the maximum amount of data that a network connection can carry in one second. It is measured in bits per second (bps), such as Kbps, Mbps, and Gbps.

4Textbookcs4-q4

What is throughput? How is it different from bandwidth?

Ans.Throughput is the actual amount of data that passes successfully in one second through a network connection. It is different from bandwidth because bandwidth is the maximum possible capacity, while throughput is the real, in-use speed, which is often slightly lower than bandwidth due to network traffic or interference.

5Textbookcs4-q5

What is data packet? How does it help in computer network?

Ans.A data packet is a small piece of data that a large message or file is broken into before being sent over a computer network. It helps a computer network by allowing large files to travel more efficiently - packets can take different paths and be reassembled at the destination, so data transfer is faster, safer, and continues even if some packets are delayed or lost.

6Textbookcs4-q6

What is frequency in telecommunication? How is it measured?

Ans.Frequency is the number of times a signal wave goes up and down (repeats a cycle) in one second. It is measured in hertz (kHz, MHz, GHz).

7Textbookcs4-q7

What is mode of data transmission?

Ans.Mode of data transmission refers to the manner or direction in which data is transmitted between two communicating devices in a network. There are three types: Simplex mode (one-way only), Half Duplex mode (both directions, but not at the same time), and Full Duplex mode (both directions at the same time).

8Textbookcs4-q8

What is wireless technology? Why is it more popular?

Ans.Wireless technology is a type of communication that transmits data through the air using radio waves, microwaves, or infrared signals, without physical cables. It is more popular because it makes communication flexible, portable, and possible over distances where wires are difficult to use, and is generally easier and cheaper to install than wired connections.

9Textbookcs4-q9

What is media converter? Write its function.

Ans.A media converter is a networking device that converts a signal from one type of network connection to another, such as converting signals between copper cable and fiber optic cable. Its function is to connect two dissimilar types of network cables so that signals can be properly converted and transmitted between them.

10Textbookcs4-q10

How does Wi-Fi transmit data?

Ans.Wi-Fi transmits data using radio waves between wireless devices and a network, through an access point that is often built into a Wi-Fi router. The router is connected to the internet by a wired connection and transmits wireless signals to surrounding devices such as smartphones, laptops, and smart TVs, using the 2.4 GHz and 5 GHz frequency bands.

11Textbookcs4-q11

How does data transmit in computer network?

Ans.In a computer network, data is broken into small data packets, each carrying part of the data along with the sender's and receiver's addresses. These packets travel through a communication channel (wired or wireless media) via networking devices such as switches and routers, possibly by different paths, and are reassembled in the correct order at the destination.

12Textbookcs4-q12

How is switch different from hub?

Ans.A hub broadcasts data to all connected devices, operates on the physical layer, uses half-duplex mode, and is not an intelligent device. A switch sends data only to the specific intended device using its address, operates on the data link layer, uses full-duplex mode, and is an intelligent device that stores MAC addresses.

13Textbookcs4-q13

What is bridge?

Ans.A bridge is a network device that links two or more network segments and passes data between them as if they were a single network. It checks the destination MAC address and decides whether to forward data to the other segment, helping to control unnecessary data traffic.

14Textbookcs4-q14

What is router? How is it different from switch?

Ans.A router is a computer networking device that links various computer networks together and forwards data between them by selecting the most appropriate path. It is different from a switch because a router works at the network layer and connects different networks (LAN, MAN, WAN) using packets, while a switch works at the data link layer and connects devices within a single LAN using frames.

15Textbookcs4-q15

What is network topology?

Ans.Network topology is the physical and logical arrangement or pattern of nodes in which computers, devices, and networking equipment are connected to each other in a network.

16Textbookcs4-q16

Write the data flow technique of ring topology.

Ans.In a ring topology, data travels through each device in the loop, either in one direction (unidirectional) or in both directions (bidirectional). Many ring networks use token passing, where a short control signal called a token circulates around the network, and only the device holding the token can send data, preventing collisions.

17Textbookcs4-q17

What is LAN? Write its features.

Ans.A LAN (Local Area Network) is a computer network that links several devices in a limited physical space, such as a house, office, school, or building. Features: (1) Covers a small area, 100 meters to 1000 meters, (2) Provides extremely fast data transfer (up to 1 Gbps or more), (3) Built with inexpensive hardware components, (4) Enables resource sharing of printers, files, and internet, (5) Is a private network, not controlled by an outside regulatory body.

18Textbookcs4-q18

Write the features of client-server architecture.

Ans.Features of client-server architecture: (1) Clients request and use services, data, and resources from a central server, (2) The server is a powerful computer that manages and stores shared resources, (3) It is a centralized architecture - the server controls access and communication, (4) The server listens to client requests and responds accordingly, (5) If the server goes down, clients may not function effectively on shared tasks, (6) It is easier to manage, secure, and scalable due to centralized control.

19Textbookcs4-q19

What is default gateway?

Ans.A default gateway is a network device, usually a router, that connects a local network to other networks or the Internet, acting as an access point through which data is sent when a device wants to communicate with a device on another network.

20Textbookcs4-q20

What is internet? Mention its merits and demerits.

Ans.The internet is a worldwide network that connects millions of computers and devices around the world for information sharing, communication, and online services. Merits: global communication, easy access to information, e-commerce and online services, remote work and learning, variety of digital services. Demerits: time-wasting, privacy risks, cybercrime, spread of inappropriate content, and slow or unstable connections.

21Textbookcs4-q21

What is IP address?

Ans.An IP address is a unique numerical label assigned to each device connected to a computer network that uses the Internet Protocol. It allows devices on a local network or the internet to locate one another and exchange data.

22Textbookcs4-q22

What is protocol?

Ans.A protocol (network protocol) is a set of rules and standards that devices follow to communicate over a network. Protocols ensure that data is properly formatted, transmitted, received, and acknowledged.

Descriptive Questions - Answer Comprehensively

1Textbookcs5-q1

Explain the differences between wired and wireless communication media with examples.

Ans.Wired media are physical channels (cables) such as CAT6 or optical fiber that transmit data through physical connections, offering faster and more stable transmission, better security, but more complex and expensive installation - suitable for fixed setups like an office LAN. Wireless media transmit data through the air using radio waves, microwaves, or infrared (e.g., Wi-Fi, Bluetooth, satellite), and are easier and cheaper to install and more flexible/mobile, but may be slower or unstable due to interference and are more prone to hacking - suitable for flexible setups like connecting a laptop or smartphone without cables.

2Textbookcs5-q2

Explain the optical fiber working principle through total internal reflection.

Ans.An optical fiber carries data as pulses of light through its core, which is surrounded by a layer called the cladding. According to the principle of total internal reflection, when light traveling through the denser core hits the boundary with the less dense cladding at a certain angle, it reflects entirely back into the core instead of passing through. This causes the light pulses to bounce along the interior of the core repeatedly, keeping the light moving within the fiber without leaking out, allowing data to travel with minimal loss over long distances.

3Textbookcs5-q3

Compare structure, advantages, and disadvantages of bus topology, star topology, and ring topology.

Ans.Bus topology: structure - all devices connect to a single backbone cable using T-connectors, with terminators at both ends. Advantage - requires the least cabling and is cost-effective and simple to set up. Disadvantage - fault-prone; if the backbone breaks, the whole network fails. Star topology: structure - all devices connect to one central device (hub, switch, or router) using separate cables. Advantage - fault tolerant; failure of one device/cable does not affect others. Disadvantage - if the central device fails, the entire network goes down. Ring topology: structure - every device connects to exactly two others, forming a closed loop, often using token passing. Advantage - data collisions are prevented since only the token holder can send data. Disadvantage - if any device or cable in the ring fails, the whole network can stop working.

4Textbookcs5-q4

Define the term bandwidth and throughput in data communication.

Ans.Bandwidth is the maximum amount of data that a network connection can carry in one second, measured in bps (Kbps, Mbps, Gbps) - it represents the total capacity of the connection, similar to the width of a water pipe or road. Throughput is the actual amount of data that passes successfully through the connection in one second while it is in use - it is the real, working speed, which is often somewhat lower than the bandwidth due to network traffic, signal strength, or interference.

5Textbookcs5-q5

Explain the key characteristics and applications of 3G, 4G, and 5G mobile communication technology.

Ans.3G (Third Generation): provided mobile internet, video calls, and faster browsing than earlier networks; used for basic mobile internet and calls. 4G LTE (Fourth Generation): offers much faster internet speed, smoother HD video streaming, online gaming, and video conferencing; used for high-speed mobile browsing and streaming. 5G (Fifth Generation): the newest and fastest, with ultra-high speed internet, very low latency, and the ability to connect many smart devices simultaneously; used to support smart cities, driverless cars, and the Internet of Things (IoT).

6Textbookcs5-q6

Define the function of repeaters, hubs, and switches in computer network.

Ans.A repeater receives signals that have become weak or faded after traveling some distance, amplifies them into strong signals, and retransmits them so they can travel effectively over long distances without loss - it is used to extend network coverage. A hub is a simple device that connects multiple devices and broadcasts data signals to all of them at once; it operates on the physical layer and is not intelligent, so all devices receive data but only the intended device uses it. A switch links multiple devices on a LAN and transfers data frames only to the specific intended device by evaluating the destination address, operating on the data link layer using full-duplex mode, making the network faster and more efficient than with a hub.

7Textbookcs5-q7

Describe the process of data transmission with radio waves, microwaves, and infrared in wireless communication technology.

Ans.In wireless communication, information is sent through signals that travel in the form of waves. Radio waves travel through the air and are used for Wi-Fi, mobile networks, and radio broadcasting - they can carry data over both short and long distances depending on frequency and power. Microwaves are higher-frequency waves used for satellite communication and long-distance point-to-point links, generally requiring a clear line of sight. Infrared signals use light waves just below visible light, work only over very short distances, are usually blocked by walls or obstacles, and are commonly used for remote controls and some short-range device communication.

8Textbookcs5-q8

Describe the application of satellites in telecommunication, and the concept of geostationary orbit.

Ans.Satellite communication is a wireless technology in which signals are sent and received via satellites positioned in space to support long-distance communication, transporting data, voice, and video signals between locations on Earth. A satellite system has a Space Segment (the satellite that sends/receives signals) and a Ground Segment (fixed or mobile stations that transmit signals to the satellite). Most communication satellites are placed in geostationary orbit, about 36,000 km above the Earth's equator, where the satellite remains fixed over one spot on Earth while covering a wide area - this makes it ideal for continuous services like television broadcast, internet access, weather forecasting, GPS, and international telephone/fax communication.

9Textbookcs5-q9

Compare LAN, MAN and WAN based on the coverage area, speed and cost.

Ans.LAN (Local Area Network): covers a small area (100 m to 1000 m, e.g., a school or office), offers very high data transmission speed (up to 1 Gbps or more), and is low-cost since it uses inexpensive hardware. MAN (Metropolitan Area Network): covers a town or city (5 km to 50 km), offers moderate data transmission speed, and costs more than a LAN since it needs more cabling and infrastructure to join distant locations. WAN (Wide Area Network): covers very large areas such as countries or continents, has data transmission speed that fluctuates from very slow to very fast, and has the highest setup, maintenance, and upkeep costs among the three.

10Textbookcs5-q10

Write the function of RJ45 connectors and media converters in networking.

Ans.An RJ45 connector is used with twisted-pair network cables such as CAT6 to connect computers, switches, routers, and other networking devices; it has 8 metal pins that make contact with the 8 wires of the cable, letting data signals flow through the cable and equipment without problems. A media converter is a networking device that converts a signal from one type of network connection to another, such as instantly converting signals between copper cable and fiber optic cable, allowing two dissimilar types of network cables to be connected together (for example, linking a fiber optic backbone to a computer room's copper CAT6 cabling).

11Textbookcs5-q11

Explain the differences between a client and a server in a network setup.

Ans.A client is a device (such as a PC, smartphone, or printer) that requests and uses services, data, or resources from a server - for example, opening a webpage, accessing a file, or printing a document. A server is a powerful, centralized computer that manages and stores resources like files, databases, printers, and internet access, and responds to requests sent by clients. In a client-server setup, communication and access are controlled by the server (centralized architecture), so clients depend on the server being available to work effectively on shared tasks.

12Textbookcs5-q12

Explain how physical barriers and interference affect wireless communication.

Ans.Physical barriers such as walls, floors, furniture, and other obstacles can block or weaken wireless signals, reducing the range and strength of a Wi-Fi or Bluetooth connection - infrared signals, for example, are easily blocked by walls and work only over very short distances. Interference from other electronic devices, overlapping wireless networks, or environmental conditions (such as rain, for satellite/wireless links) can disrupt signals, causing slower speeds, dropped connections, or reduced throughput compared to the maximum possible bandwidth. This is why wireless connections can be less stable and less secure than wired connections, which are less affected by such factors.

13Textbookcs5-q13

What is router? Explain the function of a router in a computer network.

Ans.A router is a computer networking device that links various computer networks together and forwards data between networks by selecting the most appropriate path. Function: routers are intelligent devices that examine the destination address of incoming data and determine the fastest route to send it, acting like a traffic police officer directing data to the right destination. Routers also allow multiple devices to share a single internet connection (for example, connecting a home or school's local network to the internet), and modern routers often include firewalls for added security.

14Textbookcs5-q14

Explain IPv4 addressing system and its use in computer networks.

Ans.IPv4 (Internet Protocol version 4) is the original and most widely used version of the Internet Protocol, used to identify and locate a device within a network with a numerical address. It uses a 32-bit number, divided into four parts called octets separated by dots, with each octet a number between 0 and 255 (e.g., 192.168.0.1). Since it uses 32 bits, IPv4 can create about 4.3 billion (2^32) unique addresses. IPv4 addresses are used in computer networks - including homes, schools, and offices - to identify each connected device and allow it to send and receive data, with certain ranges (such as 192.168.0.0-192.168.255.255) reserved for private, local networks.

15Textbookcs5-q15

Explain the importance of protocols in data communication.

Ans.Protocols are important in data communication because they are the set of rules and standards that devices must follow to communicate over a network. They ensure that data is properly formatted, transmitted, received, and acknowledged between devices, so that different types of devices and systems (which may be made by different manufacturers) can understand each other and exchange information accurately, securely, and efficiently. Without protocols, devices would not be able to agree on how to send, receive, or interpret data, making reliable communication over a network impossible.

16Textbookcs5-q16

Write the key features of each type of network (based on coverage).

Ans.PAN (Personal Area Network): covers a very small area (around 10 meters), connects personal devices (phones, tablets, smartwatches), uses Bluetooth, Wi-Fi, or USB, and needs no specialized networking hardware. LAN (Local Area Network): covers 100 m to 1000 m, offers very high-speed data transfer, uses inexpensive hardware, and enables local resource sharing. MAN (Metropolitan Area Network): covers 5 km to 50 km (a town or city), offers moderate speed, uses fiber optics/microwave links, and can be privately or publicly owned. WAN (Wide Area Network): covers large distances such as countries or continents, has fluctuating speed, is run by ISPs/telecom companies, and has the highest setup and maintenance cost.

17Textbookcs5-q17

Explain each type of topology with key features.

Ans.Bus topology: all devices connect to a single backbone cable using T-connectors; data travels in both directions; terminators are used at both ends to prevent signal reflection; requires the least cabling and is cost-effective; fault-prone if the backbone breaks. Star topology: all devices connect to a central device (hub, switch, or router) via separate cables; fault tolerant since a single device/cable failure does not affect others; but the whole network fails if the central device fails. Ring topology: every device connects to exactly two others, forming a closed loop; often uses token passing so only the token holder can send data, preventing collisions; the whole network can stop if any device or cable fails. Hybrid topology: combines two or more topologies (e.g., star and ring) into a single network to use their advantages and reduce drawbacks; it is flexible, scalable, and reliable, but more complex and costly to design and maintain.

18Textbookcs5-q18

Write the differences between Client-server architecture and Peer-to-Peer network architecture.

Ans.Client-Server architecture: uses one or more central servers that manage and store shared resources; clients request services from the server; it is a centralized architecture where the server controls access and communication; it is easier to manage, more secure, and scalable, but if the server fails, clients cannot access shared resources. Peer-to-Peer (P2P) architecture: each device (peer) can act as both a client and a server, sharing data and resources directly with other peers; all devices have equal status and there is no central server (decentralized); it is simple and cheap to set up for small networks, but becomes difficult to manage and less secure as the network grows large.

Case Study and Application-Based Questions

1Textbookcs6-q1

Your school wants to connect all computers in a new computer lab for sharing files and internet. Which network topology would you recommend and why?

Ans.Star topology would be recommended. In a star topology, all computers connect to a central device (such as a switch), so if one computer's cable or connection fails, only that computer is affected and the rest of the lab's network keeps working. It is also fault-tolerant, simple to maintain, and makes it easy to add or remove computers for sharing files and internet without disrupting the whole network.

2Textbookcs6-q2

A company needs to provide internet access to multiple floors without using long cables. Which communication medium should they choose?

Ans.Wireless media (Wi-Fi) should be chosen. Since data needs to reach multiple floors without long cables, a wireless connection using radio waves through Wi-Fi routers/access points allows internet access to be shared flexibly across floors without the cost and complexity of running long cables between them.

3Textbookcs6-q3

A remote health center wants to send patient data to a hospital in another city. Which type of network (LAN, MAN, or WAN) would be most suitable?

Ans.A WAN (Wide Area Network) would be most suitable. Since the health center and hospital are in different, distant cities, a WAN is needed because it is designed to connect networks over very large geographic areas (such as between cities), unlike a LAN (single building) or a MAN (a single city/town).

4Textbookcs6-q4

You are setting up a smart home where devices like lights, cameras, and door locks can be controlled from a smartphone. Which wireless technology would you use?

Ans.Wi-Fi would be used. Wi-Fi allows smart home devices such as lights, cameras, and door locks to connect wirelessly to a home network and be controlled remotely from a smartphone through the internet, without needing cables between the devices and the router. (Bluetooth can also be used for very short-range direct control of individual smart devices.)

Extra Revision Questions

1Textbookcs8-q1

Define bandwidth and throughput. How are they different?

Ans.Bandwidth is the maximum amount of data a network connection can carry in one second (measured in bps). Throughput is the actual amount of data that passes successfully through the connection at a given time, which is often lower than bandwidth due to traffic, signal strength, or interference.

2Textbookcs8-q2

Differentiate between a hub and a switch.

Ans.A hub broadcasts data to all connected devices, operates on the physical layer, uses half-duplex mode, and is not intelligent. A switch sends data only to the intended device, operates on the data link layer, uses full-duplex mode, and is intelligent (stores MAC addresses).

3Textbookcs8-q3

Differentiate between IPv4 and IPv6.

Ans.IPv4 uses a 32-bit address written in decimal (e.g., 192.168.0.1) and supports about 4.3 billion addresses. IPv6 uses a 128-bit address written in hexadecimal (e.g., 2001:db8::7334) and supports an almost unlimited number of addresses, with better built-in security.

4Textbookcs8-q4

Differentiate between Intranet and Extranet.

Ans.An Intranet is a private network accessible only to authorized users within an organization, used for internal communication and information sharing. An Extranet extends the intranet to also allow limited, secure access to selected external users such as clients, suppliers, or partners.

5Textbookcs8-q5

A school has two computer labs located far apart, and the network signal becomes weak between them. Which networking device should be used to solve this problem, and why?

Ans.A repeater should be used. It receives signals that have become weak or faded after traveling some distance, amplifies them into strong signals, and retransmits them, strengthening the network connection between the two distant labs.

6Textbookcs8-q6

Suppose you want to check whether a website's server is reachable and measure the response time. Which command-line utility would you use, and what does it show?

Ans.The PING command should be used. Running 'ping <website address>' checks whether the server is reachable and measures the time data packets take to travel to the destination and back (the response time), helping detect network delays or failures.

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