Bus, Star and Ring Topologies
How are the wires laid out between devices?
- Draw bus, star and ring topologies
- State one strength and one weakness of each
- Identify the topology of the school lab
Overview
Topology is the shape of a network — the map of who is connected to whom. Different shapes handle failures, growth and cost very differently.
Bus
All devices tap into a single long cable (the 'bus'). Cheap and simple for a few PCs, but if the main cable breaks, everyone drops off. Rare today except in old industrial systems.
Star
Every device has its own cable back to a central switch. If one cable fails, only that PC is affected. This is the topology of almost every school lab, office and home Wi-Fi router setup today.
Ring
Each device is connected to two neighbours, forming a loop. Data circulates in one direction. Used in some industrial and telecom rings (fibre metro rings) because if one link breaks, traffic can go the other way around.
Human Topology
- Six students stand up. Using string, form a bus, then a star (one student is the switch), then a ring.
- For each shape, the teacher 'breaks' one link. Discuss who loses connectivity.
- Which topology fails completely if the main cable breaks?
Reveal answer
Bus.
- Which is most common in modern LANs?
Reveal answer
Star.
- Why do fibre rings still exist in telecom networks?
Reveal answer
Traffic can flow the other way if one link breaks — good fault tolerance.
Draw the topology of the school lab as accurately as you can, marking every switch and cable.