Computer Networks

Question 1

What is a network?

Answer 1

A network is two or more computers, or other electronic devices, connected together so that they can exchange data.

Question 2

What are some examples of network functions?

Answer 2

• Sharing files
• Messaging users
• Sharing a printer
• Centralized data storage

Question 3

What methods are used to create network connections?

Answer 3

• Cables (wires)
• Radio signals (wireless/WiFi)
• Telephone lines (modems)
• Satellite links

Question 4

Why use networks?

Answer 4

• Easily share files and data
• Share resources such as printers and Internet connections
• Communicate with other network users
• Store data centrally for ease of access and back-up
• Keep settings centrally for workstation use

Question 5

What are some benefits of connecting to the Internet through a network?

Answer 5

• Access online services (e-commerce, banking)
• Research information
• Access entertainment (games, video)
• Join online communities

Question 6

What are some drawbacks of using networks?

Answer 6

• Vulnerability to hackers
• Network failure complicates tasks
• Increased risk of virus attacks

Question 7

What precautions should be taken when using a computer connected to the Internet?

Answer 7

• Avoid revealing personal information
• Avoid suspect websites that may contain malware
• Verify the accuracy and reliability of online information

Question 8

What are the two categories of computers in a network?

Answer 8

• Clients
• Servers

Question 9

What is the role of client computers in a network?

Answer 9

Client computers, or workstations, are the normal computers that people use to get their work done.

Question 10

What services do servers provide in a network?

Answer 10

• Central file storage
• Sharing hardware (printers)
• Controlling network access
• Sharing Internet connections

Question 11

Why are servers more expensive than normal computers?

Answer 11

Servers are built to be very reliable.

Question 12

What is a Local Area Network (LAN)?

Answer 12

A LAN is a network confined to one building or site, often a private network belonging to an organization.

Question 13

What is a Wireless Local Area Network (WLAN)?

Answer 13

A WLAN is a LAN that uses radio signals (WiFi) to connect computers instead of cables.

Question 14

What is the purpose of a wireless switch or router in a WLAN?

Answer 14

It is used for sending and receiving data to the computers.

Question 15

What are some advantages of WLANs?

Answer 15

• Convenience of wireless connections
• Eliminates need for running long wires

Question 16

What are some challenges of WLANs?

Answer 16

• More difficult to secure
• Risk of unauthorized access

Question 17

What is a Wide Area Network (WAN)?

Answer 17

A WAN is a network that extends over a large area, often joining several LANs together.

Question 18

What types of technologies are often used for WAN connections?

Answer 18

• Optical fibre cables
• Satellite radio links
• Microwave radio links

Question 19

What is Bluetooth?

Answer 19

Bluetooth is a wireless networking technology designed for very short-range connections.

Question 20

What is the typical range for Bluetooth connections?

Answer 20

Typically just a few meters.

Question 21

What are typical uses of Bluetooth?

Answer 21

• Connecting wireless keyboards or mice
• Using wireless headsets
• Printing wirelessly
• Transferring data/music/photos
• Synchronizing calendars

Question 22

What is a Network Interface Card (NIC)?

Answer 22

A device that allows a computer to connect to a network

Most modern computers have NICs built into the motherboard, but some require an extra expansion card.

Question 23

What is the primary function of network cables?

Answer 23

To connect different devices to form a network

Cables are preferred for their ability to carry more data per second and their enhanced security.

Question 24

What is a hub in networking?

Answer 24

A device that connects multiple computers to form a LAN

Hubs are considered ‘dumb’ devices as they send received messages to all connected computers.

Question 25

True or False: Hubs provide secure communication in a network.

Answer 25

False ## Footnote Hubs are not secure since all messages sent are broadcast to every computer on the network.

Question 26

What distinguishes a switch from a hub?

Answer 26

A switch sends received messages only to the intended recipient ## Footnote This makes networks using switches more secure than those using hubs.

Question 27

What is the role of a router in networking?

Answer 27

To connect two or more networks together ## Footnote A common use is to connect a LAN to the Internet (WAN).

Question 28

What additional functionality does a wireless router provide?

Answer 28

It connects a LAN to the Internet wirelessly ## Footnote A wireless router combines the functions of a router and a wireless switch.

Question 29

What is a proxy server?

Answer 29

A computer that shares an Internet connection ## Footnote It retrieves web pages on behalf of other computers and can implement additional software like anti-virus.

Question 30

What is the primary purpose of a bridge in networking?

Answer 30

To link two different parts of a LAN ## Footnote Unlike routers that connect LANs to WANs, bridges connect independent parts of a LAN.

Question 31

What is a firewall?

Answer 31

A device or software that protects a network from unauthorized connections ## Footnote It allows normal data (e.g., emails, web pages) while blocking other data.

Question 32

What was the primary function of a modem in the past?

Answer 32

To connect computers to the Internet via telephone lines ## Footnote Modems convert digital signals to analogue signals and vice versa.

Question 33

What does DAC stand for in the context of a modem?

Answer 33

Digital-to-Analog Converter ## Footnote It converts digital data from the computer into analogue signals for the telephone line.

Question 34

What is the function of the ADC in a modem?

Answer 34

Analog-to-Digital Converter ## Footnote It converts analogue signals received from the telephone line back into digital data.

Question 35

Fill in the blank: A modem is required because computers are _______ devices and the telephone system is analogue.

Answer 35

digital

Question 36

What is the Internet?

Answer 36

A world-wide network that has evolved from an experimental network created by the US military in the 1960s ## Footnote The experimental network is known as ARPANet.

Question 37

What has contributed to the growth of the Internet?

Answer 37

The connection of more computers and networks over the years ## Footnote This has transformed it into the Internet we know today.

Question 38

What types of entities does the Internet connect?

Answer 38

Millions of people and thousands of businesses, governments, schools, universities, and other organizations ## Footnote The Internet serves a diverse range of users.

Question 39

What is an intranet?

Answer 39

A private network that provides similar services to the Internet, such as e-mail and web pages, but is restricted to its users ## Footnote Intranet services are private and not public.

Question 40

Who typically uses intranets?

Answer 40

Businesses and other organizations for their employees ## Footnote Intranets are designed for internal use.

Question 41

What are typical uses of an intranet?

Answer 41

Viewing internal web pages, internal e-mail, instant messaging, and sharing of internal documents ## Footnote These functions facilitate communication and information sharing within organizations.

Question 42

Fill in the blank: An intranet provides similar services to the Internet, but these services are _______.

Answer 42

private

Question 43

True or False: The services provided by an intranet are generally public.

Answer 43

False ## Footnote Intranet services are specifically for internal users.