Network topology describes how devices are connected in a network. Two common topologies are star (all devices connect to a central switch) and mesh (devices connect to multiple other devices).
Key points
Definition:Star Topology: each device has its own direct connection to a central switch. The switch routes data to the correct recipient.
Definition:Mesh Topology: each device is connected directly to multiple other devices. Data takes the most efficient path.
Star advantages: easy to add/remove devices, failure of one cable does not affect others, no collisions on cables.
Star disadvantages: if the central switch fails, the whole network goes down; expensive due to amount of cabling.
Mesh advantages: very reliable — if one connection fails, data can take an alternative route; fast data transfer via shortest path.
Mesh disadvantages: requires a LOT of cabling and network ports, especially in a full mesh.
Exam Tip:Know at least TWO advantages and TWO disadvantages for each topology. Always relate to the specific topology's structure.
Common Mistake:Saying star topology uses a 'server' at the centre. It uses a SWITCH (or hub) — not necessarily a server.
Star topology: single point of failure — if the SWITCH fails, the ENTIRE network goes down. But if one cable/device fails, only that device is affected.
Exam Tip:When drawing a star topology diagram, ALL devices connect ONLY to the central switch. No device-to-device connections. Label every device clearly.
Common Mistake:Adding extra connections between devices in a star diagram (that creates a mesh). In a star, EVERY connection goes through the central switch.