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

2. Learning Objectives
Understand the different characteristics of network topologies (bus, ring,
Star and mesh)

3. Bus Ring Star Network Topologies
Key word: “Topology”. This means the layout of a network.
There are four different ways (topologies) of laying out a network. They are called:
Bus
Ring
Star

4. Advantages: Disadvantages: BUS Server Printer Main Cable Terminator
A BUS network is a cheap and easy way of setting up a network.
Server
Printer
Terminator
Main Cable
Advantages:
The simplest and cheapest to install and extend;
Failure of one node does not affect the rest of the bus network
Disadvantages:
If the main bus cable fails then the whole network will fail;
Performance of the network slows down rapidly with more nodes or heavy network traffic

5. Advantages: Disadvantages: Ring Node
A ring network uses a one-way system
Advantages:
Cheap to set up as there is no central server or switch.
Disadvantages:
Cable failure anywhere will affect the whole network
Need to ‘break’ the ring in order to add a new node
All nodes must be switched on for the network to work properly.
Node

6. STAR Terminal Switch Server Printer
Many people believe Star networks are the best solution
Terminal
Advantages:
Fastest performance
Easy to install and to expand with extra nodes
A failure in the minor cables will only affect one node
Disadvantages:
Uses the most cable which makes it more expensive
An extra hub or switch further increases the cost
Switch
Server
Printer

7. MESH
A mesh topology is a network topology in which all the network nodes are individually connected to most of the other nodes. There is not a concept of a central switch, hub or computer which acts as a central point of communication to pass on the messages.
Advantages:
The failure of one node will only affect that node
Channel failure will have no effect as alternative channels are available
Disadvantages:
Extra cabling makes this an expensive
Complex cabling leads to higher maintenance of the network.

8. Activity
In PowerPoint, design your own school network using the icons provided.
Server
Terminal
Laptop
Printer
WWW
Router
Switch
Wi-Fi
Tablets
You must annotate your diagram:
Label hardware.