The ICT Lounge
 
Section 4.3:
The different Types of Networks
 

There are different types of computer networks and they all have their advantages and disadvantages.

In this section we will discuss the features each type.

Key Concepts of this section:
#
Understand that there are four types of computer networks.
#
Know the features of each type of computer network.
#
Be able to describe the advantages/disadvantages of each type of computer network.

Types of computer networks
Key Words:
LAN, WLAN, WAN, Bluetooth.
#
There are four main types of computer networks:
  • LAN (local area networks)
  • WLAN (wireless local area networks)
  • WAN (wide area networks)
  • Bluetooth.
Examples:
A network is just two or more computers joined together.
We will discuss the features of each network type, as well as their advantages/disadvantages below:


Local Area Networks (LAN)
 
#
Local area networks (or LAN's) are usually located in a single room or small building.

Examples:
A LAN consists of several computers connected together in order to share resources.
(click to zoom)
 
LAN's are confined to one room or a small building.
LAN's allow networked computers to share resources (like printers).
LAN's allow network managers to monitor users (like checking internet usage and passwords).
LAN's are computer networks that are confined to small areas.

#
An example of a LAN would be a school network. The computers on the network would be confined to a classroom or the school.

#
LAN's are private and can only be accessed by people in the room or the building.

For example:
A school network is only used by students who attend the school.

#
A typical LAN would consist of several computers that are connected to each other and can share resources such as printers and scanners.

#
Computers and devices on a LAN are connected using cables.

Advantages and disadvantages of LAN's:
Advantages of LAN's
Disadvantages of LAN's
Saves money as each computer on the LAN can share resources.

(For example - you only need to buy one printer because it can be shared between all the computers on the network)
Viruses can spread around LAN's very quickly.

(This is because the computers are all joined together - if one computer gets infected, the other are at risk)
Files and data can be shared easily.

(Like the shared drive on a school network)
Security can be an issue.

(If one computer is hacked into, the other computers on the network can also be accessed)
Files and data can be accessed from any computer on the network.

(For example - it doesn't matter which computer in the school you log onto, you can access your work files)
The network can become unusable if the main server computer breaks down.

(You won't be able to log onto any of the client computers on the network)
Data (like emails) can be sent around a LAN very fast.

(The cables that connect the computers can handle very fast data transfer)
Slow internet connections.

(All of the computers on the network share the same internet connection. This can make it slow for users)
LAN's can be monitored easily.

(Network managers can check people's internet usage or change passwords etc)
Initial cost of installing the LAN is high.

(Buying cables and equipment etc)



Wireless Local Area Networks (WLAN)
 
#
WLAN's are similar to LAN's but they connect computers together wirelessly instead of using cables

Examples:
WLAN's use wireless technology instead of cables to connect computers and devices to the network.
(click to zoom)
 
A router can be used to send/receive data wirelessly to/from devices on the network.
Devices outside of the router's wireless range limit will not be able to connect to the network.
Any wi-fi enabled devices can connect to a wireless network. (click to zoom)
This is achieved using Wi-Fi technology.

#
Routers or wireless switches are used to send and receive data around the network.

#
Client computers or devices send and receive data using wireless adaptors.

Most modern laptops, tablets and mobile phones come with built-in Wi-Fi adaptors.

#
A typical router can send/receive data to/from computers up to 50 metres away.

Note:
Most home networks are WLAN's. They use a router to allow several computers or devices to use the same internet connection.

Advantages and disadvantages of WLAN's:
Advantages of WLAN's
Disadvantages of WLAN's
Physically safer than a LAN because there are no cables to trip over.

Some areas in the building may not pick up the wireless signal.

(This means that computers or devices may not connect to the network from certain locations)
Cheaper to set up than a WLAN because you don't have to buy lots of expensive cables.
Security can be an issue as anyone with a wireless enabled device can try to access the network.

(It's very important the network is secured with an encrypted password)
Easier to add more computers to the network.

(All they need is a wireless adaptor and they can then communicate with other computers on the network)
Wireless signals can be unreliable as they sometimes suffer from interference from other electronic equipment.

(Cables used on LAN's are far more reliable)
Devices such as printers and scanners can be connected to the network easily.

(Some printers/scanners have built-in wireless adaptors)
Data transfer around a wireless network is much slower compared to a LAN.

Computers and devices can be used anywhere in the building.

(As long as they are in range of the network's router)
WLAN's can be useless for use in a large building as the signal range is limited.

(Computers can typically communicate with the router up to about 50 metres)








Wide Area Networks (WAN)
#
Wide area networks are made up of computers and devices that are connected over a large geographical area.

Examples:
WAN's are lots of networks and computers connected together over a large area. (click to zoom)
 
Computers and devices can connect to a WAN using routers, cables or even satellite signals.
The internet is the world's largest WAN. It is millions of computers and devices linked together all over the world.
Transferring files across a WAN can be slow.
Computers connected to a WAN are more at risk of security risks like viruses and hackers.
The internet is the world's largest WAN.

The internet is just millions of computers all over the world that have been connected together so they can share data.

#
WAN's are created by connecting lots of LAN's and individual computers together.

Every time you switch on your Wi-Fi connection or access mobile data (on your phone), you are connecting your device or computer to a WAN.

#
Computers and devices can connect to a WAN using telephone lines, fibre-optic cables and satellite signals.

#
In order to connect your computer to a WAN you also need a router or a modem.

Routers and modems allow your computer to send/receive data to/from other computers on the WAN.

Advantages and disadvantages of WAN's:
Advantages of WAN's
Disadvantages of WAN's
Computers can be connected over wide areas.

(Across cities or even continents)

Security can be an issue as anyone with access to the internet can potentially access any of the computers on the network.

(Computers on the network need to be secured with a firewall and important files should be encrypted)
Files and data can be shared over a large area.
It's very easy to accidentally download viruses from a WAN onto your computer.

(You need to make sure that your computer is protected with up-to-date anti-virus)
People can use their computers/devices to communicate very quickly, over large areas.

(Sending emails, discussion forums, video conferencing etc.)
Data is transferred across a WAN at a much slower rate than it is across a LAN.

(Download speeds are limited)
E-Commerce (shopping) websites can be set up and accessed by people from all over the world.

(This allows people with disabilities to purchase items online and have them delivered to their door)
Monitoring a WAN can be difficult because they have so many computers connected to them.

(This means that inappropriate content may be uploaded)
Computers and devices can be used anywhere in the building.

(As long as they are in range of the network's router)
Bluetooth (WPAN)
#
Bluetooth is also known as a Wireless Personal Area Network (WPAN).

Examples:
Bluetooth networks are known as 'personal networks' because devices have to be close together in order to connect. (click to zoom)
 
Bluetooth devices connect together wirelessly up to a range of 10 metres.
Bluetooth transfer speeds are very slow.
Bluetooth connections are not very secure and easy for hackers to break into.
#
Bluetooth devices can connect to each other from between 1 and 100 metres away.

The connection is made without using wires or cables.

Bluetooth uses radio waves to transmit data.

#
Once two devices are connected with bluetooth, you can transfer files and data between them up to the maximum range of 100 metres.

Note:
Devices which can make use of bluetooth include:
Mobile phones
Tablets
Wireless Mouse
Wireless Speakers

Advantages and disadvantages of Bluetooth:
Advantages of Bluetooth
Disadvantages of Bluetooth
Very easy to connect bluetooth devices together.

(you just switch on your bluetooth and wait for the devices to pair)
Limited signal range.

(With the normal signal range limit of only 10 metres, the two devices need to be close-by to connect)
Bluetooth signals are not easily to disrupt.

(They aren't easily affected by other electrical devices like Wi-Fi can be)
Slow data transfer. Bluetooth is not suitable for transferring large files.

(Bluetooth cannot transfer data between devices as fast as Wi-Fi.)
Works wirelessly so there are no messy cables needed to connect devices.

Very unsecure connections and easy for hackers to break into.

(Bluetooth is not as secure as Wi-Fi and makes it unsuitable for transferring sensitive or private data)

Bluetooth uses very little power.

(This means that using bluetooth won't drain your devices battery quickly)

Activity!

Click the above task and answer the questions about
the 4 different types of computer networks.


Please add your questions/comments below:
 

Links to Theory Units:
 
Links to Practical Units:
Section 11: File Management
Section 12: Images
Section 13: layout
Section 14: Styles
Section 15: Proofing
Section 16: Graphs and Charts
Section 17: Document Production
Section 18: Data Manipulation
Section 19: Presentations
Section 20: Data Analysis
Section 21: Website Authoring