Star And Mesh Topologies

Question 1

What is a network topology?

Answer 1

• A layout of computer systems on a local network.

Question 2

What is star topology?

Answer 2

• Each computer system is connected to a central device, usually a hub or switch.

Question 3

How does a star topology work?

Answer 3

1) - Each computer system is connected to the central hub or switch and transfers its data packets there.

2) - The hub or switch looks at the destination address and transfers the packets directly to the intended computer.

Question 4

Advantages of Star Topologies:

Answer 4

• Improved security because data packets are sent directly to and from the hub / switch in the centre and not necessarily all devices like in a bus or ring topology.
• New systems can be attached directly to the central system so the network doesn’t need to be shut down.
• Transfer speeds are generally fast as there are minimal network collisions.

Question 5

Disadvantages of Star Topologies:

Answer 5

• Extra hardware (the hub/switch) is required to be purchased, installed and maintained.
• If the central system (hub/switch) fails, then the whole network will be unusable until the error is fixed.

Question 6

Full Mesh networks:

Answer 6

• Each computer system is connected to every other computer system.

Question 7

Partial Mesh Networks:

Answer 7

• Where some nodes (e.g a printer) are connected to every other node.

Question 8

How do mesh topologies work?

Answer 8

• Data packets are transferred to the destination address along the quickest path, travelling from node to node.
• If a pathway is broken, there are many alternative paths that the packets can take.

Question 9

Advantages of Mesh Topologies:

Answer 9

• If one cable or system fails then data packets can take an alternative route and still reach the destination address.
• Because of the large possible number of systems and connections, a mesh topology can usually withstand large amounts of data traffic.
• New systems can be added to the network without disrupting the entire topology.

Question 10

Disadvantages of Mesh Topologies:

Answer 10

• Because of the possibly large amount of cables required, this can be expensive to install and maintain.
• Redundant cabling should be avoided - this is when cables are connected between systems that won’t ever need to communicate.

Question 11

Redundant Cabling definition:

Answer 11

• When cables are connected between systems that won’t ever need to communicate.