Exam Tips - Network Topologies

Exam Tips - Network Topologies

Most common exam questions:

• "Describe star topology" → All devices connect to central switch. Data goes device → switch → destination.
• "Advantage of star?" → Easy to add devices / isolated failures (one cable break = one device affected)
• "Disadvantage of star?" → Central switch = single point of failure (if it dies, ALL devices lose connection)
• "Describe mesh topology" → Devices connect to multiple/all other devices. Multiple paths for data.
• "Advantage of mesh?" → No single point of failure / very reliable (data finds alternative paths)
• "Disadvantage of mesh?" → Very expensive (lots of cables) / complex to manage
• "Compare star vs mesh" → Star: cheaper, single point of failure. Mesh: expensive, very reliable

Key comparison facts to memorize:

Aspect	Star	Mesh
Structure	Central switch	Multiple interconnections
Single Point of Failure?	YES (switch)	NO (redundant paths)
Cost	Moderate	Very High
Reliability	Moderate	Very High
Use Case	Homes, offices, schools	Critical systems, data centers

Common mistakes to avoid:

• Confusing "central switch fails = all down" with "one cable fails = all down" - in star, one cable = one device!
• Saying star has no single point of failure - it does (the switch)!
• Thinking mesh is used everywhere - it's only used for critical systems due to cost
• Forgetting bus and ring are largely obsolete - exams focus on star vs mesh
• Not explaining WHY mesh is reliable (multiple paths for data)

Perfect exam answer structure:

"Compare star and mesh topologies" (4 marks):

Star: All devices connect to central switch (1 mark).
Mesh: Devices connect to multiple other devices (1 mark).
Star has single point of failure (central switch) (1 mark).
Mesh has no single point of failure, data takes alternative paths (1 mark).