Communication (Networks and Internet)

Question 1

What are the main components of networks?

Answer 1

Cloud (internet)
Modem
Router/ firewall
WAP (Wireless Access Point) 
Workstation (Node)
Network switch
Server

Question 2

What is the difference between a Hub and a switch?

Answer 2

Hub- copies all packets of data to all devices in a network which causes network traffic which slows down network performance.
Switch- Analyses each packet of data and sends it to the node it was intended for.

Question 3

What does the modem do?

Answer 3

It converts analogy data from wires and converts it to digital data (1s and 0s) that the network can use and the other way round.

It is sometimes found in the router.

Question 4

What are the network types?

Answer 4

PAN- Personal Area Network-
Usually limited to a single building (around 10 meters) to connect an individuals technological devices.

LAN- Wide Area network - Spread over a small geological area confined to a single site such as the school.

MAN - Metropolitan Area Network- Spread over a large area that will connect a number of LANs over several buildings to cover a city.

WAN- Wide Area Network- spread over a large geological area over multiple buildings or sites.

Question 5

What does the router to?

Answer 5

A router stores the address of computers on a network and transfers data between devices. It connects the network to another network.

Question 6

What does a WAP do?

Answer 6

A Wireless Access Point is requeired to connect a network wirelessly. It is usally built into a router (eg, broadband router).

Question 7

What does a bridge do??

Answer 7

It conects two networks together with the same base protocals. (Eg a LAN to a LAN)

Question 8

What does a gateway do?

Answer 8

Connects two networks together with differenct base protocals (Eg a LAN to a WAN).

Question 9

What is the description of a bus topology?

Answer 9

Where all nodes connect directly to a single linear cable (bus). On each end of the cable there is a terminator which stops signals from reflecting back.

Question 10

What is the description of a star topology?

Answer 10

A network where each node (workstations and the server) is connected to a central hub or switch

Question 11

What is the purpose of a server in a network?

Answer 11

To provide information or services to other computers in the network. It can be used for it’s processing power or be used as a shared storage area.

Question 12

What are the advantages and disadvantages of using a bus topology?

Answer 12

Pros
- One of the easiest and cheapest servers to set up
- No switch or hub needed which could have failed and lead to the network shutting down
- less cables
Cons
- The wire use could lead to bottle necking or data collisions with data flowing in both directions. This could lead to network traffic and slow it down.
- Single point of failure with the one main bus
- the performance weakens as more nodes are added to the network due to data collisions
- Each node ‘sees’ all the data in a network which creates a security risk.

Question 13

What are the advantages and disadvantages when using a star topology?

Answer 13

Pros
- It is very reliable as there is one cable assigned to each node, limiting data collisions and bottlenecking
- High transfer speeds
- Data can only travel to its intended destination when using a switch
- Easy to identify faults when troubleshooting
- if a cable fails, the network will carry on working.
- easy to add extra nodes
Cons
- Time consuming to set up and physically route each cable
- Expensive to set up with extra hardware (cables and switch)
- Single point of failure with the switch/ hub.

Question 14

What is a firewall?

Answer 14

Checks incoming data and scans it for harmful or malicious files or ones that are banned by the network admin.