1.4 Wired and Wireless Networks

Question 1

What are standalone computers?

Answer 1

Computers not connected to a network.

Question 2

What are the advantages of networking standalone computers together?

Answer 2

1) Users can share files and peripherals.
2) Users can access their files from any computer on the network.
3) Server can control security, software updates and backup of data.
4) Communication with others e.g. email and social network.

Question 3

What are computers in a LAN connected with?

Answer 3

Switch.

Question 4

What does a LAN cover?

Answer 4

A small geographical area located on a single site.

Question 5

How does a LAN cover the area?

Answer 5

Wired through a UTP cable, fibre optic or wireless, using WIFI/ radio waves.

Question 6

What does a WAN cover?

Answer 6

A large geographical area (connecting LAN’s together).

Question 7

How does a WAN connect LAN’s together?

Answer 7

Infrastructure between LAN hired from telecommunication companies who own and manage it.

Connected with telephone lines, fibre optic cables or satellite links.

Question 8

What are computers in a WAN connected with?

Answer 8

Router.

Question 9

What are the disadvantages of networking?

Answer 9

1) Increased security risk to data.
2) Malware and viruses spread easier between computers.
3) If a server fails, computers connected to it may not work.
4) Computer might run slowly if there’s lots of data travelling on it.

Question 10

Define bandwidth

Answer 10

How much data can be transferred over a connection in a given time.

Question 11

How is bandwidth shared between users?

Answer 11

Through internal networks and WAN.

Question 12

What are the two types of copper Ethernet cable used at the moment?

Answer 12

1) Cat-5
(slower: 100 Mbps)

2) Cat-6
(faster: 1Gbps)

Question 13

Why is fiber optic cable good and bad?

Answer 13

Faster; more expensive.

Question 14

How do fiber optic cables transfer data?

Answer 14

By reflecting beams of light through one end of the cable to the other.

Question 15

What can effect wi-fi performance?

Answer 15

Latency: Max. speed a connection can go.

Throughput: Amount of traffic a network can carry at a time.

Packet Loss: Glitches, errors, or network overloading might result in the loss of data packets.

Retransmission: When packet loss does occur, those lost packets are retransmitted.

Question 16

What are the two radio bands for wi-fi?

Answer 16

2.4 and 5GHz.

Question 17

Is wireless or wired network cheaper?

Answer 17

Wireless (wi-fi) - Only needs WAP for its set up.

Wired network - Cost more to set up in a building
(cable management).

Question 18

Define hub

Answer 18

A basic networking device that connects computers on the network
(cables connect the computer to ports on the hub).

Question 19

How is a hub different from a switch and router?

Answer 19

It has no routing tables nor intelligence on where to send information.

Broadcasts all network data across each connection.

Question 20

Define switch

Answer 20

Similar to a router; directs network traffic only to the intended recipient not across every connection, helping in data collisions.

Builds up a table of addresses of the computers on the network.

Question 21

Define router

Answer 21

Device for connecting computers and other network capable devices together to form a network.

Question 22

What does a WAP allow?

Answer 22

Wireless devices to connect to a network (LAN or WAN) through Bluetooth.

Question 23

What do WAP’s provide?

Answer 23

Internet access in public places (often known as wi-fi hotspots).

Question 24

What happens when a data packet arrives at a switch?

Answer 24

Its destination address is examined.

Switch creates a direct connection to that device.

Question 25

How do routers allow packets from different network types to be exchanged?

Answer 25

1) They examine IP addresses of packets using a subnet mask.
2) The subnet mask determines which network the packet should be forwarded to using the routing table.
3) The routing table has a list of IP addresses and common routes for packets to take.

Question 26

What does the network interface card allow?

Answer 26

1) A computer to connect to a wireless network.

2) Data packets to travel to and from a computer.

Question 27

What does a network interface card contain?

Answer 27

A MAC address:

Physical hardware address and is unique to that computer.

Question 28

What is the difference between a client model and peer to peer model?

Answer 28

Client server is a network that uses a server and peer to peer model doesn’t.

Question 29

What are the properties of a client-server model?

Answer 29

1) Manages internet access and printing jobs.
2) Controls access and security to one shared file store.
3) Provides email services.
4) Runs backup of data.
5) Requests data and connections to the server.

Question 30

What is easier when using a client server?

Answer 30

1) Managing security of files.
2) Taking backups of all shared data.
3) Installing software updates to all computers.

Question 31

What are the disadvantages of using a client server?

Answer 31

1) Expensive to set up and maintain
2) Requires IT specialists to maintain
3) If the servers fail, users will lose access

Question 32

What is a peer to peer model?

Answer 32

Multiple computers that can share and connect to each other but there is no central server managing it.

Question 33

What is a peer and what do they serve?

Answer 33

A computer on the network and is equal to all other peers who serve their own files to each other and are responsible for their own security and backup.

Question 34

What are the advantages of a peer to peer model?

Answer 34

1) Easy to maintain – specialist staff aren’t required.
2) Doesn’t depend on a single computer.
3) Cheaper to set up – no expensive hardware required.

Question 35

What are the disadvantages of a peer to peer model?

Answer 35

1) Network is less secure.
2) Users manage their own security and backup.
3) Difficult to maintain a well ordered file store.