Networks

Question 1

What is a bus topology

Answer 1

A type if topology where a long cable, called the backbone, connects all the computers together

It has terminators at the end that stop the charges from bouncing back

Question 2

What is a star topology

Answer 2

Start topology is a type of topoly where there is a central switch or hub and all other devices are connected to that switch using its own cables

Question 3

How is data transmitted in bus topology

Answer 3

The data is sent from one computer along the backbone cable and the data packets are then sent to every single computer/device

The devices then read the MAC address of the recipient and the device with that MAC address opens the files

The devices where the MAC address does not match just discard the data and don’t open it

Question 4

How is data transmitted in the star topology

Answer 4

The data is sent from the sending device down its cable to the switch/hub

The switch/hub reads the mac adress of the recipient and then sends the data along the cable to the device that matches the mac adress of where is was addressed to

Question 5

Why is star topoly so expressive

Answer 5

High cabling costs as each device needs its own cables to connect it to the switch/hub

Question 6

Advantages of start topologies

Answer 6

If one cable fails only one workstation is affected rather than the whole network

Consistent performance as few collisions as each workstation has its own cable to the server

More secure as messages from the computer go directly to the centre and then only o the recipient

Easy to add more devices

Question 7

Disadvantages of star topology

Answer 7

Installation usually requires an expert to set it up

Dependence on the central computer as if it fails the whole network goes down

Very high cabling costs

Question 8

Advantages of bus topology

Answer 8

Easy to install

Uses less cables than a start topology meaning its cheaper

Can easlily add new computers/work stations

Question 9

Disadvantages of bus topology

Answer 9

Performance slows down as the amount of traffic increases

Low security as every workstation can see them data on the network

Can be costly to install dye to having to move existing thing as for cable

If main cable fails then the whole network goes down

Question 10

LAN

Answer 10

Local area network
Covers a small geographic area located on a single site
Can be wired or wireless
Usually high-speed because the network is confined to a small area.

Question 11

PAN

Answer 11

Personal area network
Connect devices over a very short range
Normally centred around a single user
Example is Bluetooth

Question 12

WAN

Answer 12

Wide area network
WAN connects LANs that are in different geographical locations

Question 13

Benefits of networks

Answer 13

Sharing files is easier as network users can access the same files and work on them at the same tune

Can share multiple hardwares such as printers between multiple devices

Can communicate across a network cheaply and easily

User accounts can be stored centrally so users can log in from any device on the network

Question 14

Disadvantages of networks

Answer 14

They can be expensive to sera up as they often need extra hardware

Can be vulnerable to hacking and malware can easily be spread between networked computers

Some networks are dependant on servers, and if a server goes down it can be very disruptive for people tryin to use the network

Large networks are difficult to manage and need specialised management

Question 15

What is a NIC

Answer 15

Network interface card

A piece of hardware un a device that allows it to connect to a network

Question 16

Switch

Answer 16

Switches are devices that connect devices on a LAN

Question 17

Routers

Answer 17

read the IP address of each packet at the Internet layer to decide the best path for it to travel.

Question 18

Whag is bandwidth

Answer 18

The amount of data that can be sent across a network in a given time

Question 19

Describe Fibre optics

Answer 19

They are cables that transmit data as light

High performance and very expensive

Don’t suffer interference and can transmit over very large distances

They have a very high bandwidth

Question 20

Descibe CAT 5E and CAT 6 cables

Answer 20

Ethernet cables

Contain pairs of copper wires which are twisted toghere to reduce internal interference

They are cheaper than fibre optic cable and have an alright bandwidth

They are commonly used in homes

Question 21

Descibe coaxial cables

Answer 21

Made up of a single copper wires surrounded by plastic layer for insulation and metallic mesh to prevent shielding from outside interference

They are very cheap, but have a low bandwidth

Question 22

WLANs

Answer 22

Local wireless networks

Eg Wi-Fi

Question 23

How to set up WLAN

Answer 23

You need a WAP device

Question 24

What does a WAP do

Answer 24

A switch that allows devices to connect to the network wirelessly

Question 25

Hotspots v WAP

Answer 25

Hotspots are locations where you can connect to a WAP

Question 26

Benefits kf wireless networks

Answer 26

- are convenient as you can get your device to connect automatically to the network and you can also move around while connected - they are cheaper and better for the environment as you don’t need a lot of wires - it’s very easy to add more users, you don’t need to add extra wires

Question 27

Disadvantages of wireless networks

Answer 27

- genrally less secure than wired networks as access points are usually visible to all devices, not just trusted ones which can cause hackers to gain access - distance from the WAP, interference from other wireless networks and physical blocks like walls can all reduce signal length (there’s a limit on how far a wireless metwork can reach) - they havw a lower bandwidth and are generally less reliable

Question 28

What is a network protocol

Answer 28

A set of rules for how devices communicate and how data is transmitted

Question 29

What are packets

Answer 29

Data sent between networks that has been split equally

Question 30

What is a layer

Answer 30

A group of protocols that have similar functions

Question 31

Why are the 4 layers (in order)

Answer 31

Application layer Transport layer Internet layer Link layer

Question 32

What does the application layer do

Answer 32

Where network applications such as web browsers or email applications operate

Question 33

Transport layer protocol

Answer 33

Sets up communication between sender and recipient (establishes a connection). Splits data into packets so large messages can be sent over the network. Checks all packets are delivered (reliable delivery). Requests retransmission if any packet is lost or corrupted. Reassembles the packets into the original message for the application layer. This is the TCP protocol we learnt about

Question 34

What does the internet layer do

Answer 34

Adding IP addresses to data packets directing them between devices handling traffic

Question 35

Link layer used for

Answer 35

Passing data over the physical network Responsible for how the data is sent as electrical signal over cables, wireless and other hardware Interpreting signals using device drivers

Question 36

Eg of application layer protocol

Answer 36

HTTP(S) FTP IMAP SMTP

Question 37

eg of transport layer

Answer 37

TCP UDP

Question 38

Eg Of internet layer

Answer 38

IP

Question 39

eg of link layer

Answer 39

Wi-Fi Ethernet

Question 40

What are the advantages of using layers?

Answer 40

It breaks down network communication into manageable pieces, This helps developers concentrate on only one area of the network without having to worry about the others There is a self contained meaning they can be changed without the other layers being affected Having several rules for each layer of forces companies to make compatible universal hardware and software so different brands will work with each other and always work in the same way

Question 41

What is HTTP?

Answer 41

It stands for hyper text transfer protocol It’s used by browsers to access websites and communicate with web servers

Question 42

What is HTTPS?

Answer 42

HTTP secure A more secure version of HTTP as it encrypted all the information that is sent and received between your device and the web server

Question 43

What is FTP?

Answer 43

File transfer protocol It’s used to edits and move files between devices on a network Operates on application layer

Question 44

What is IMAP

Answer 44

Internet message access protocol Used to retrieve emails from the server

Question 45

What is SMTP?

Answer 45

Simple meal transfer protocol Used to send emails and to transfer emails between servers

Question 46

Which layer do the five main protocols work on?

Answer 46

The application layer

Question 47

What does transport layer do

Answer 47

Setting up communication between sender and recipient. Breaking down large messages into smaller units (packets) so they can be sent across the network. Ensuring all packets are delivered to the recipient. Reassembling the packets into the original message for the application layer.

Question 48

What is IP

Answer 48

IP stands for Internet Protocol. It is responsible for addressing and routing packets across a network. Ensures packets reach the correct device on the network. Works with TCP to deliver data reliably.

Question 49

Main 5 protocols on application layer

Answer 49

HTTP/HTTPS IMAP SMTP FTP

Question 50

MAC address filtering

Answer 50

MAC address filtering is a network security method that controls which devices can connect to a network by using their unique physical (MAC) address. It involves creating a safelist (or whitelist) of allowed MAC addresses or a blocklist of disallowed ones, with the safelist being the more secure method

Question 51

Firewall

Answer 51

The firewall inspects and controls incoming network traffic to determine which traffic should be rejected or accepted depending on a set of rules set by a government, an organization, or an individual.

Question 52

How can MAC address filtering be triscked

Answer 52

MAC address spoofing

Question 53

Encryption

Answer 53

Scrambling messages or data sung s specific cypher or key to make fhe data unreadable Symmetric encryption = same key used to encrypt and decrypt Asymmetric encryption = public key to encrypt and secret key to decrypt