1. Network topologies

2. What is a network topology? Physical arrangement of the devices in a communications network. Most commonly used are bus and star. Usually a combination of these two, referred to as hybrid or tree networks.

3. Bus topology Many devices connect to a single cable ("backbone“). If the backbone is broken, the entire segment fails. Relatively easy to install and don't require much cabling compared to the alternatives.

5. Ring topology Every device has two neighbours for communication purposes. Messages travel through a ring in the same direction. A failure in any cable or device breaks the loop and will take down the entire segment. If any device is added to or removed from the ring, the ring is broken and the segment fails until it is reforged“. Considerably more expensive than other topologies.

7. Star topology Has a central connection point - like a hub or switch. Involves more cable If a cable fails, only one node will be brought down. The central hub is usually a fast, self contained computer and is responsible for routing all traffic to other nodes. The main advantage of a star network is that one malfunctioning node does not affect the rest of the network. Can be prone to bottleneck and failure problems at the central site.

9. Hybrid/tree topology Also known as the 'Hierarchical topology‘. A combination of bus and star topologies. Very common in larger networks. Typical scenario is: a file server is connected to a backbone cable that runs through the building, from which switches are connected, branching out to workstations.

11. Activities Make a list of advantages/disadvantages for the topologies. What topologies to you feel are outdated? What type of topology does the school use? Why do you think they have chosen this one? What topology would you suggest for a small business? Home network? Large business? Why?