Computer Networks

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Revision as of 11:58, 15 November 2019 by 000032680 (talk | contribs) (Question 12)
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Types of Network

Computer Science Tutor

https://www.youtube.com/watch?v=TdQgP_Gee_A&list=PL04uZ7242_M6O_6ITD6ncf7EonVHyBeCm&index=29

Local Area Network

Local Area Networks (Also known as "LAN") is a form of networking that allows devices to communitcate to eachother and networks, LAN is connected via an Ethernet cable then connected to a server or a router to connect to a network or another device. LAN is connected by Ethernet Cables, these are made up of coxial cable in different types. This, for a long time, was the only way to connect a computer as they used to have where they would connect to a mainframe and then a computer would be connected by Ethernet cable to the mainframe, making it a Local Area Network.

Wide Area Network

A Wide Area Network, or WAN, is made up of several computer networks connected together, often over the Internet. In most cases, the networks in WANs all belong to the same company or school. WANs are used to connect LANs and other types of networks together, so that users and computers in one location can communicate with users and computers in other locations. Many WANs are built for one particular organization and are private. Others, built by Internet service providers, provide connections from an organization's LAN to the Internet.

The following image demonstrates how a wide area network is used in a computer network:

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Why do we network devices

Benefits of Networking

  • Sharing devices like printers saves money.
  • Site licences are likely to be cheaper than buying several standalone licences.
  • Files can easily be shared between users.
  • Network users can communicate by email.
  • Security is good, users cannot see other users' files unlike on stand-alone machines.
  • Data is easy to backup as all the data is stored on the file server.
  • Single password per user instead of per device.

Drawbacks of Networking

  • Purchasing the network cabling and file servers can be expensive.
  • Managing a large network is complicated, requires training and a network manager usually needs to be employed.
  • If the file server breaks down the files on the file server become inaccessible.
  • Viruses can spread to other computers throughout a computer network.
  • There is a danger of hacking, particularly with WANs.
  • If there's a break in the network is down no work on computers can take place.

Revision Questions

Question 1

1. what does CSMA/CD (carrier sense multiple access with collision detection) do when a collision is detected?

stops sending data from all included devices and produces an error message
doesn't just just sending
stops sending data all devices wait a random ammount of time then retry
correct
keeps retrying until sent
incorrect this would not work and will stop the computer
data is transfered through the air instead
this cannot be done with this protocol or possible in these systems

Your score is 0 / 0


Question 2

1. Select all the benefits of networking:

All devices such as printers are independent to a machine which saves money
Incorrect
Files can easily be shared between users
Correct
Data is easy to backup as all the data is stored on the file server
Correct
It's easier to travel
Leave your fridge open to stop global warming.
Site licences are likely to be cheaper than buying several standalone licences
Correct

Your score is 0 / 0


Question 3

1. Which of the following apply to a LAN? (Multiple Answers)

It is a form of networking that allows devices to communicate with each other and networks
This is correct.
It is connected via fibre optic
This is incorrect; it is connected via Ethernet
It is connected via coaxial cables in the form of Ethernet
This is correct.
It was the only way to connect a computer for a long time.
This is correct; they used to connect a mainframe to a computer via ethernet
It is a geographically remote network
This is incorrect; it is geographically confined.

Your score is 0 / 0


Question 4

1. Define a Peer-peer network:

Devices connected to a server to communicate with each other
Incorrect
Devices with equal status, with no servers connected
Correct
Devices connected to a WAN
Incorrect

Your score is 0 / 0


Question 5

1. Which of the following are typically LAN connection medium?

satellite link
satellite link is not local area
Ethernet Cable
Correct
Fibre Optic cable
No
Wireless connection
Correct

Your score is 0 / 0


Question 6

1. What does LAN stand for?

Logical active network.
Local area network was the correct answer.
Nothing
Bruh.
Local area network.
Noice one.
Live area network.
Local area network was the correct answer.

Your score is 0 / 0


Question 7

1. What does WAN stand for?

Wired Access Network
Incorrect, it stands for Wide Area Network
Wide Area Network
Correct
Wireless Anatomy Network
Incorrect, it stands for Wide Area Network
Wayne's Army Network
NO! It stands for Wide Area Network

Your score is 0 / 0


Question 8

1. What are the communications media used in a WAN

Ethernet
Yes
USB.
no
Router.
yes
Hub.
this is not wrong
Switch
incorrect
Coaxial cable

Your score is 0 / 0


Question 9

1. Which of these is not a drawback of using LAN?

Saves money by sharing devices, like printers
This is a benefit
Managing a LAN is complicated
Easy to back up data
This is a benefit
Viruses can spread to other computers throughout the network

Your score is 0 / 0


Question 10

1. State the advantages of a star topology over the bus topology.

Less chance of data collisions
Correct
Easier to detect faults
Correct
Less cable overall is needed
Incorrect
Easier to connect a computer or peripheral compared to a bus topology
Incorrect
No disruptions to the network when removing and connecting devices
Correct

Your score is 0 / 0


Question 11

1. Which of these is an benefit of networking?

Files can easily be shared between users.
Correct answer
Purchasing the network cabling and file servers can be expensive.
The correct answer is "Files can easily be shared between users."
Managing a large network is complicated, requires training and a network manager usually needs to be employed.
The correct answer is "Files can easily be shared between users."
Viruses can spread to other computers throughout a computer network.
The correct answer is "Files can easily be shared between users."

Your score is 0 / 0


Question 12

1. Define the term protocol:

A device that a network can connect to
Incorrect
A set of rules that computers use to communicate with each other
Correct
A network topology layout
Incorrect
The type of communication method used when computers connect
Incorrect

Your score is 0 / 0