3.3 Network characteristics

Question 1

What is a client server network?

Answer 1

A client server network simply works where a client (computer) requests and the server responds by sending programs and data. They are centrally controlled making the system more secure.

HOWEVER, malware can spread across the network, large amounts of traffic congestion can slow down the network

Question 2

What is a peer to peer network?

Answer 2

A P2P network is where data is shared directly between the systems without a centralised server. Each computer can switch from client to server and each responsible for providing data. Optimal for sharing files.

HOWEVER, no central device to ensure security or back up data.

Question 3

What is a star network?

Answer 3

There is a central device (hub / switch) where it is connected to other systems. The connected systems transfer data to the central device and transfers the packets to a specifically listed computer.

Advantages
- Less data collisions.
- if one device / cable fails, other devices are unaffected

HOWEVER
- if the central device fails so does the whole network.
- expensive to install as lost of cabling and central device is required

Question 4

What is a bus topology?

Answer 4

All devices are connected to a cable which transfers all the data. Each message travels along the bus but only intended device accepts the message.

Advantages
- Cost effective as it uses less cabling.
- simple to set up
- doesn’t require a specialised central device
- easy to add new devices

HOWEVER,
- data collisions are likely as data is transferred on the same line.
-If the bus fails, no one can communicate
- security issues as all devices receive the data packets

Question 5

What is a mesh topology ?

Answer 5

Each computer system is connected to every other computer system.

Advantages
- Data travels along the quickest path.
- If one system fails there are other paths available.

HOWEVER,
- because of the high cabling it can be more expensive to install and maintain.
- hard to add another device as cables are required to connect to all other devices

Question 6

What is a token ring topology?

Answer 6

Devices are connected to two other devices forming a ring / loop. Data is sent in one direction.

Advantages
- no specialist device is needed
- topology is simple to set up
- no data collisions

HOWEVER,
- if any system fails then the other devices may not be able to communicate
- some devices may view messages not meant for them
- adding new devices requires a network shutdown

Question 7

What are the functions of an IP address?

Answer 7

• An IP address are assigned to each devices connected to the internet
• enable hosts to be identified so packets can be sent to them
• give an indication of where the device is geographically located

Question 8

What is a default gateway?

Answer 8

A device that links networks and forwards packets with IP addresses outside of the network.
When a device with an IP address can’t be found on a network, it is sent via a default gateway.

Question 9

What is a subnet and subnet mask?

Answer 9

A subnet is a smaller part of a network. This helps reduce traffic.

A subnet mask is used to determine these subnets.

Question 10

What is a DNS and how does it work?

Answer 10

The domain name system translates between IP addresses and domain names. The web browser connects to a DNS server to search for domain names in its database, if it can’t find any it’ll connect to other DNS servers which will eventually provide a domain names IP address.