Computer Networks

  • Define what a computer network is.
  • Discuss the advantages and disadvantages of computer networks.
  • Describe the main types of computer network including:
    • Personal Area Network (PAN)
    • Local Area Network (LAN)
    • Wide Area Network (WAN).

Computer Networks

  • A computer network is two or more computers or devices that are linked together.
  • They are connected either using wires or wirelessly.
  • This allows them to communicate with each other and share resources.
  • Some additional examples of networked devices are:
    • smartphone
    • tablets
    • games consoles
    • wearables

Advantages - Costs

  • Reduce hardware costs:
    • Share peripheral devices
    • Allow a single internet connection to be used by many devices

Advantages - Sharing

  • Share information
    • Exchange data between computers without using physical media (memory stick, external hard drive)
    • Back-up files centrally

Advantages - Security

  • Improve security
    • Centrally control security
    • Maintain the firewall
    • Centrally control software updates
    • Control which users have access to the network and what resources they can access

Advantages - Mobility

  • Improve mobility of users
    • Log into any computer and still access the same resources
    • Files can be accessed anywhere
    • Separate computers are not needed for every user

Disdvantages

  • Additional hardware is needed to set up a network and large networks will need a network manager to oversee the system.
  • If one machine is infected with malware, it can quickly spread to the other machines on the network.
  • Hackers may target a network to gain access to many computers.
  • If there is a file server that fails, users will not be able to access their files.

Types of Computer Network

  • Personal area network (PAN)
  • Local area network (LAN)
  • Wide area network (WAN)

Personal Area Network (PAN)

  • Connects devices over a very small area
  • Range is a few metres (approx. 10 m)
  • Usually Bluetooth (short-wave radio)
  • Headphones, printer, speakers...

Local Area Network (LAN)

  • Connects devices over a small area, usually one site
  • Home, school, company office
  • The hardware is usually owned by the organisation using the network
  • Often uses wired and wireless connections

Wide Area Network (WAN)

  • Used by large organisations to connect multiple LAN's over a large geographical area.
  • The largest WAN is the Internet.
  • The infrastructure (hardware) are usually hired/leased from a telecommunication company.
  • Banks are a good example of a WAN, multiple branches all around the country, each has its own local area network connected back to the head office using a wide area network.
  1. State two advantages of using a computer network.
  2. State two disadvantages of using a computer network.
  3. Describe the characteristics of a LAN.
  4. Give one example of a type of technology used in a PAN.
  5. Identify two differences between a LAN and a WAN.

Questions

  1. State two advantages of using a computer network.

Answers

  • Sharing hardware devices
  • Sharing an internet connection
  • Storing files centrally
  • Managing software centrally
  • Managing security centrally
  • Backups managed centrally
  1. State two disadvantages of using a computer network.

Answers

  • Additional hardware is needed to set up the network
  • Networking hardware can be expensive
  • Malware can spread easily between networked devices
  • If a central file server fails, users cannot access their files
  • Larger networks will need to be overseen by a network manager
  1. Describe the characteristics of a LAN.

Answers

  • A network in a small geographical area, such as a home, school, office on a single site.
  • The hardware is usually owned by the organisation that uses it.
  • Often uses both wired and wireless connections.
  1. Give one example of a type of technology used in a PAN.

Answers

  • Bluetooth
  1. Identify two differences between a LAN and a WAN.

Answers

  • A LAN is a network covering a small geographic area; a WAN covers a wide geographic area.
  • The networking hardware in a LAN is usually owned and maintained by the organisation that uses it; the connections in a WAN are usually hired or leased from a telecommunications company.

5a Computer Networks

By David James

5a Computer Networks

Computer Science - Computer Networks - Computer Networks

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