Chapter 2. Communication

Question 1

What is a network topology

Answer 1

An arrangement of devices in a network

Question 2

What is a network

Answer 2

A link between two or more computers through which they communicate, enabling them to share data, software and hardware.

Question 3

Advantages of a network

Answer 3

• Enables files and data to be backed up centrally
• Allows sharing copies of software(multiuser licenses are cheaper)
• Allow multi-access to files
• Hardware resources such as printers and internet connections can be shared
• Communicate with network users (instant messaging, email, video conferencing
• Licences are cheaper when used on a network than on standalone machines

Question 4

Disadvantages of networks

Answer 4

• More difficult to secure as compared to standalone systems and they are vulnerable to hacking, phishing and pharming
• If server breaks down, work comes to a standstill
• Viruses spread more easily in network environments
• Managing large networks can be a complex task
• There’s an expensive initial investment in infrastructure(servers and cabling)

Question 5

Expand the acronym APRAnet

Answer 5

Advanced Research Projects Agency Network

Question 6

What are the advantages of a bus network

Answer 6

1. Continues to function even when one node fails
2. Easy to expand - just adding more nodes

Question 7

What are the disdvantages of a bus network

Answer 7

1. Fails if the main cable fails
2. Performance detiriorates under heavy load
3. Not secure since each packect passes through every node

Question 8

Differentiate between a hub and a switch

Answer 8

A hub sends packets to all devices in a star configuration but only the node with the matching address accepts the packet whilst a swith only sends the packets to the node with the right address

Question 9

Advantages of a star topology

Answer 9

1. Data collisions are greatly reduced
2. More secure since security methods can be applied to the central node
3. Easy to improve just by installing an upgraded hub
4. If one connection is broken then only one node is affected

Question 10

Disadvantages of star topologies

Answer 10

1. Initial installation costs are high
2. If the hub/switch fails, the whole network goes down

Question 11

Give the names and explain the two types of data transfer incorporated by mesh networks

Answer 11

1. Routing
   The nodes are given routing logic and data is directed to its destination by the shortest route possible
2. Flooding
   Data is just send via every node to its destination

Question 12

What are the advantages of mesh networks

Answer 12

• Easy to identify where faults occured
• Broken links do not affect the whole network
• Good privacy and security
• Relatively easy to expand

Question 13

What are the disadvantages of mesh networks

Answer 13

• A large amount of cabling is required
• Set-up and maintenance is difficult and complex

Question 14

What is a Local Area Network (LAN)?

Answer 14

• A LAN connects computers within a limited area such as a home, school, or office building.
• Uses Ethernet or Wi-Fi for connections.

Question 15

What are the characteristics of a Wide Area Network (WAN)?

Answer 15

• A WAN covers a large geographic area.
• Uses leased telecommunication lines.

Question 16

What is the purpose of a router?

Answer 16

• Directs data packets between networks.
• Connects multiple devices to the internet.

Question 17

What is the difference between a client-server and a peer-to-peer network model?

Answer 17

• Client-server: Central server manages resources and services.
• Peer-to-peer: Each computer can act as a server and client.

Question 18

What are the benefits of using a client-server model?

Answer 18

• Centralized management of resources and security.
• Easier to backup and manage data.

Question 19

What are the benefits of using a peer-to-peer network?

Answer 19

• Easier to set up and manage.
• No need for a dedicated server.

Question 20

What is the role of a Network Interface Card (NIC)?

Answer 20

• Provides the hardware interface between a computer and a network.
• Converts data into a format suitable for transmission over a network.

Question 21

What are the common network topologies?

Answer 21

• Bus: All devices share a single communication line.
• Star: All devices are connected to a central hub.
• Mesh: Devices are interconnected with many redundant connections.

Question 22

What is the difference between wired and wireless networks?

Answer 22

• Wired networks use physical cables for data transmission.
• Wireless networks use radio waves for data transmission.

Question 23

What are the advantages of using fiber-optic cables over copper cables?

Answer 23

• Higher bandwidth and faster data transmission.
• Less susceptible to electromagnetic interference.

Question 24

What is cloud computing?

Answer 24

• Accessing and storing data and applications over the internet instead of on local servers or personal devices.
• Offers scalability and remote access.

Question 25

What are the types of IP addresses?

Answer 25

- IPv4: 32-bit address format. - IPv6: 128-bit address format.

Question 26

What is the purpose of the Domain Name System (DNS)?

Answer 26

- Translates human-readable domain names (e.g., www.example.com) into IP addresses. - Enables users to access websites using names instead of numerical IP addresses.

Question 27

What are public and private IP addresses?

Answer 27

- Public IP: Assigned to devices that are accessible over the internet. - Private IP: Used within private networks and not directly accessible from the internet.

Question 28

How does packet switching work?

Answer 28

- Data is broken into packets and each packet is sent independently over the best available path. - Packets are reassembled at the destination.

Question 29

What is the difference between static and dynamic IP addresses?

Answer 29

- Static IP: Permanently assigned to a device. - Dynamic IP: Temporarily assigned by a DHCP server.

Question 30

What are the benefits of using bit streaming?

Answer 30

- Enables real-time or on-demand delivery of digital media over the internet. - Allows users to watch videos or listen to music without downloading the entire file first.

Question 31

What is the importance of broadband speed in bit streaming?

Answer 31

- Higher broadband speeds improve the quality of streaming by reducing buffering and providing smoother playback. - Affects the resolution and frame rate of streamed content.