2.1.1 Networks including the internet

Question 1

Purpose and Benefits of Networking Devices.

Answer 1

• Allows for communication between machines.

- Allows sharing of files and data, increase availability of information.

Question 2

Characteristics of a LAN.

Answer 2

• Covers a small geographical area.
• Typically cheaper than WAN
• LANs typically have higher bandwidth than WANs

Question 3

Characteristics of WAN.

Answer 3

• Covers a large geographical area.
• Typically more expensive
• WANs typically have a lower bandwidth than LANs.

Question 4

Describe what is meant by a client-server model of networked computers.

Answer 4

When a server provides services/applications to other computers referred to as ‘clients’. The client sends requests, the server sends back responses.

Question 5

Describe what is meant by a peer-to-peer model of networked computers.

Answer 5

When each node in the network operates as both the ‘client’ and the ‘server’, eliminating the need for a central server.

Question 6

Benefits of the client-server model.

Answer 6

• Clients can be less powerful machines, therefore less expensive to buy.
• Files and resources are centralised, meaning that it is easier to update resources and data.

Question 7

Benefits of the peer-to-peer model.

Answer 7

• More resilient, if one node is taken down, the network still works.
• Adaptable, a P2P network extends to include new clients easilt allowing it to be more flexible than client-server networks.

Question 8

What is a thin-client?

Answer 8

A thin-client is designed to be small and lightweight, meaning that most of the processing is done on the server.

This means that it requires a constant connection to the server.

Question 9

What is a thick-client?

Answer 9

A thick-client performs the bulk of processing in the client-server application, meaning continuous connection to the server is not required.

Question 10

What is a bus topology?

Answer 10

• Uses a central cable which all nodes are connected.
• One node can only send one packet at a time, but data is sent down the central bus in both directions.
• A Terminator is attached at each end to ensure signals do not bounce back.

Question 11

What is a star topology?

Answer 11

• Network controlled by central server (can be router, server computer or switch), which controls how data is moved around the system.
• Every device has it’s own dedicated connection to the central server.

Question 12

What is a mesh topology?

Answer 12

• Every node has a dedicated connection to every other single node.
• As every device has a direct path to every other device, data collision cannot occur.

Question 13

Benefits of a bus topology.

Answer 13

• Easier to setup/extend.

- Less cable required.

Question 14

Drawbacks of a bus topology.

Answer 14

• If main cable breaks, network performance badly degraded.

- Collisions happen, not suitable for network with high amounts of traffic.

Question 15

Benefits of a star topology.

Answer 15

• Secure as signals only get sent to the destination.
• Fewer data collisions, can handle more network traffic.
• Failure of one node or link does not affect rest of network.

Question 16

Drawbacks of a star topology.

Answer 16

• If central device fails the whole network goes down.

- Performance dependant on capacity of central device/chokepoint?

Question 17

Benefits of a mesh topology

Answer 17

• If one link breaks, the whole system still works.

- Since each node has a dedicated connection to every other node, high amounts of traffic can be handled.

Question 18

Drawbacks of a mesh topology.

Answer 18

• Expensive because multiple links needed between each node.

- Flexibility, adding or removing a node is difficult because of multiple links.

Question 19

What is a hybrid topology?

Answer 19

• When multiple topologies are combined to make a a network.
• Weakness of each topology can be considered and singled out through network.
• Expensive as multiple network hubs needed.