1.3: COMPUTER NETWORKS, CONNECTIONS AND PROTOCOLS 2.0

Question 1

what are the 2 common models for connecting computers over a network?

Answer 1

client-server networks

peer-to-peer networks

Question 2

what is a client?

Answer 2

a computer that relies on other computers (servers) to provide and manage data

Question 3

why are clients in a client-server network limited? (2)

Answer 3

• do not usually store data

- they have no control over the network as a whole or over individual computers.

Question 4

what are client-server network best suited for? (2)

Answer 4

• organisations with many computers

- situations where many computers need access to the same information.

Question 5

what are P2P network best suited to? (2)

Answer 5

• smaller organisations that have fewer computers

- situations where fewer computers need access to the same data.

Question 6

what do all computers in a P2P network have? and what does this mean?

Answer 6

equal status

- no computer has control over the network.

Question 7

what is each computer known as in a P2P?

Answer 7

peer

Question 8

Describe the relationship between a client and a Web Server. (4)

Answer 8

• A web server holds the data needed for the website (both the content of the website and the layout).
• When someone wants to view a web page their web browser sends a request to the web server.
• web server processes request and prepares the data that has been requested, before sending it back.​
• The web browser then receives that data and displays the web page to the viewer.

Question 9

what are devices in a network connected by?

Answer 9

a wired/ wireless medium

Question 10

what is a computer or device that is not connected to a network is called?

Answer 10

a stand-alone

Question 11

which hardware components are required to connect a computer to a network? (3)

Answer 11

• a network interface controller/card (NIC) or wireless network interface controller
• a transmission medium (either wired or wireless)
• a point to connect to, such as a router, hub, switch or wireless access point

Question 12

what do most modern devices have? why?

Answer 12

a NIC and a wireless NIC built in

-providing the option of either connection method.

Question 13

what do transmission medias do? what are they either?

Answer 13

carry data signals from one computer to another

-wired or wireless

Question 14

which wired transmission medias are used in modern networks? (2)

Answer 14

• twisted copper wiring (ethernet)

- fibre-optic cable.

Question 15

characteristics of twisted copper wire and fibre-optic cable: (6)

in terms of:

• cost:
• maximum transmission speed:
• maximum distance for reliable communication:

Answer 15

cost:
TCW: Cheap
FO: Expensive

maximum transmission speed:
TCW: much slower
FO: extremely fast

maximum distance for reliable communication:
TCW: Up to 100 metres
FO: Over 2 kilometres

Question 16

advantages and disadvantages of wired networks: (2)

Answer 16

ADVANTAGES:
-reliable as not usually subject to interference.

DISADVANTAGES:
-limited mobility - as wired device has to stay in place.

Question 17

advantages and disadvantages of wireless networks: (3)

Answer 17

ADVANTAGES:
-ideal for mobile devices as a device can connect to a network as long as it is in the range of a wireless access point.

DISADVANTAGES:

• use radio waves to carry signals; these signals are limited in range (usually up to 50 metres),
• subject to magnetic interference - can also be blocked by walls.

Question 18

what can WAPs also be used for? and how? (2)

Answer 18

• can be used to extend range of a wireless network.

- WAP can either receive and transmit traffic to other WAPs, or be connected via a cable to the main network.

Question 19

3 advantages of using the cloud:

Answer 19

• ability to access files from any location or any device, so long as an internet connection exists
• access can be granted to another user so they can remotely access your data
• reduced need to make backups - cloud storage services back up the data for you

Question 20

3 disadvantages of using the cloud:

Answer 20

• there is no guarantee that someone else is not accessing your data
• Security – Data stored online is vulnerable to security attacks.​
• access to data is only possible with an internet connection - no connection means no access to data

Question 21

what is network performance in reference to? give an example

Answer 21

response time

-how fast a message can be sent or how quickly a document can be retrieved

Question 22

what would a website that is hosting need to do?

Answer 22

would need to have registered domain name with a domain registrar

Question 23

what can hosting do? what will it be placed it?

Answer 23

enable other people see your web site, which will be placed on a web server.

Question 24

why does a website that is hosting need to have registered with a domain name register?

Answer 24

they would ensure that the domain name is unique and not already registered

Question 25

advantages of a star topology: (2)

Answer 25

If one computer on the network fails, the rest of the network continues to function normally.​ Centralised management of the network, through the use of the central computer, hub, or switch.​

Question 26

disadvantages of a star topology: (2)

Answer 26

High level of dependence on one single, central device.​ Expensive (Network hardware eg switches + Technician).​

Question 27

advantages of a mesh topology: (2)

Answer 27

A failure of one device does not cause a break in the network or transmission of data.​ Manages high amounts of traffic, because multiple devices can transmit data simultaneously.​

Question 28

disadvantages of a mesh topology: (2)

Answer 28

Impractical to set up because of the high number of connections needed.​ Many connections require a lot of maintenance.​

Question 29

what is the cloud?

Answer 29

Remote servers that are used to store data and run applicaitons that are accessible via the internet

Question 30

why would websites need to have registered domain name with a domain registrar?

Answer 30

they would ensure that the domain name is unique and not already registered