1. Communication and the Internet
Year 10 Computer Science
Communication and the Internet

2. Learning Objectives
Understand why computers are connected in a network;
Understand the different types of networks, including LAN and WAN;

3. Starter Activity - Video
Consider this:
Why do we think it is a good idea to network computers together?
What do we hope to gain from networking computers together?

4. Definition: What is a Network?
A network is two or more computers connected together to share information and resources.
(this can involve physical or wireless connections, or both).

5. Advantages of Networking
Users can share files with each other;
Users can share peripheral devices, such a printers and scanners;
Users can share a connection to the internet;
Users can access their files from anywhere on the network;
Allows for easy communication between multiple people.

6. Disadvantages of Networking
However, connecting computers in a network can also be disadvantageous, for the following reasons:
Increased security risk to data
Malware and viruses spread very easily between computers
If the central server fails, the computers connected to it may not work
Networks can be extremely expensive to set up, regardless of whether they are wired or wireless networks.

7. LAN, WAN and PAN LAN (Local Area Network) WAN (Wide Area Network)
There are two main types of networks, including:
LAN (Local Area Network)
WAN (Wide Area Network)

8. LAN – Local Area Network
A LAN is a Local Area Network.
It is a local connection of computers and devices.
Usually operate on a single site or within a single institution
Each device on a network is known as a node (e.g. computer, printer, etc.)
Examples include:
A school network
An office network
Can you think of any others?

9. WAN – Wide Area Network A WAN is a Wide Area Network
WAN’s cover a wide geographical area
They can connect multiple LAN’s together
They are connected via telephone lines, fibre optic cables and satellite link
The internet and an ATM network are both great examples of WAN’s.

10. Activity - Books Date, Title “Computer Networks”
Write the definition of a network. Make it stand out!
Explain the difference between a LAN and a WAN.
Answer the question:
A school with 20 stand alone PCs is considering networking them together.
Explain four possible benefits of doing this.
Explain two drawbacks of doing this.
Extension. Consider whether the school should use a wireless or wired connection. Justify your decision.