1.4 Connecting computers to a LAN

Question 1

NIC

Answer 1

network interface controller

computer need a NIC or adapter to connect to a wireless/wired network

the NIC formats the data sent and received by the computer

NICs are often built on chips on the computer motherboard

uses a protocol to ensure a successful communication

Question 2

MAC address

Answer 2

media access control address

every NIC is created with a MAC number programmed into it

the MAC address ensures that data is delivered to the correct computer

Question 3

hubs and switches

Answer 3

hubs and switches are used to link computers so that they can communicate with each other once they have connected using the NIC

switches and hubs affect the performance of networks by their effect on the amount of network traffic

Question 4

hubs

Answer 4

send every message to every computer on the network

this creates extra unnecessary traffic

Question 5

switches

Answer 5

read the destination addresses (MAC/NIC address) of the messages and relays them only to the intended recipients

sends data between computers in a LAN

Question 6

routers

Answer 6

connect different networks together

read address information and forward the messages to the correct network

used to transfer data between a home network and the internet (connects a LAN to a WAN)

uses IP address on a device to route traffic to other routers

Question 7

wireless access points

Answer 7

wireless devices need wireless access points to connect to cabled networks

they convert data received through cable into wireless signals and vice versa

like hubs, they do not read the destination addresses and direct messages to all devices

wireless access points are often used for hotspots in public buildings (security is more of a problem)

Question 8

Both hubs and switches can be used to connect the devices in a network

a) Explain one advantage of using a switch rather than a hub [2]
b) State the function of a network router [1]

Answer 8

a) a switch reads the address information of each message and directs it to the correct recipient
this reduces the amount of network traffic whereas a hub sends a message to every computer; creating extra network traffic

b) a router forwards data traffic between computer networks

Question 9

Explain how a network switch is able to identify the correct computer to which it must transmit a message [2]

Answer 9

each device on the network has a unique MAC address

a switch relays the address information in the message and relays the message only to the computer with that address