Topologies
Choosing and Comparing Topologies
A topology recommendation needs two parts: name star or mesh, then justify it by linking its features to the needs of that network. Saying “mesh is better” is not a justification; saying “mesh gives multiple routes, so one broken link does not disconnect the devices” links the feature to reliability.
Comparing the two
| Feature | Star | Mesh |
|---|---|---|
| Cabling | Each wired device has its own cable to the central switch. | A wired mesh connects many pairs of devices, so it uses far more cable. |
| Cost | Fewer cables than an all-connected wired mesh, but the switch costs money. | Wired cabling can be expensive; a wireless mesh can avoid some cable costs. |
| Reliability | The central switch is a single point of failure. | Multiple routes make it generally more reliable. |
| Faults | A failed device or its cable affects only that device. | Faults can be harder to find, though other routes keep data moving. |
| Expansion | Add a device with one new connection. | Add a device by linking it to one or more existing devices. |
| Typical setting | A business local area network with a switch at the centre. | Where reliability, redundancy or avoiding long cable runs matter. |
Making a recommendation
For example, a new escape room venue has four game rooms, each holding a control computer, plus one switch in the staff area. Star is the better choice: the layout is simple, each room is wired separately to the switch, which is less cabling than an all-connected wired mesh linking every room to every other room, and adding a fifth room later means one new connection. If the cable to one room is damaged, the other three games keep running, so the fault is contained. The switch is still a single point of failure, so keeping a spare is sensible. A wireless mesh might suit a temporary outdoor cinema spread across a field, where multiple routes improve reliability and long cable runs are avoided.
Do not claim that either topology is automatically faster: performance depends on the transmission media and other network factors.
Practise this
OCR GCSE Computer Science · Topologies