What a MAC address is

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Quick Questions

Shade in the A or B circle for each question.

1. A MAC address identifies which part of a device?

A Its network interface card (NIC)

B The network it is connected to

2. A laptop has both a Wi-Fi adapter and an Ethernet port. How many MAC addresses does it have?

A One, shared by the whole laptop

B Two, one for each NIC

3. Which statement about a MAC address is correct?

A It is a network address

B It is a hardware address

4. What does MAC stand for in MAC address?

A Media Access Control

B Machine Address Code

5. How many NICs can share the same MAC address?

A None, each NIC has a unique one

B All NICs in the same building

Match the Pairs

Draw a line connecting each item on the left to its match on the right.

Left column		Right column
100:1A:2B:3C:4D:5E		AA MAC address is a hardware address for one NIC. It does not depend on the network. An IP address is the network address.
2Wi-Fi NIC + Ethernet NIC		BAn example MAC address: a unique hardware identifier for one network interface card (NIC)
3Each NIC has its own MAC address, so a laptop with Wi-Fi and Ethernet has two different ones		CMAC address -> NIC
4A MAC address is a hardware address that belongs to the NIC, not a network address		DTwo NICs in one device, so the device has two MAC addresses
5laptop (Wi-Fi + Ethernet) = 1 MAC address		Ewifi_mac != ethernet_mac
6MAC address = network address that changes on each network		FA MAC address belongs to a NIC, not to the whole device. A laptop with Wi-Fi and Ethernet has two NICs, so it has two MAC addresses.

Definitions

MAC address

Fill in the Blanks

Complete each line of code by filling in the missing parts.

nic1.___ ← "00:1A:2B:3C:4D:5E"

IF wifi.mac __ ethernet.mac THEN OUTPUT "Different hardware" ENDIF

nics ← ["Wi-Fi", "Ethernet"] macCount ← ______(nics)

address ← "MAC" ______ "Hardware, not network"

wifiNIC.mac ← "00:1A:2B:3C:4D:5E" ethNIC.mac ← "00:1A:2B:3C:4D:5F" laptop.macCount ← _

Spot the Error

Shade in the letter of the line that contains an error.

Question 1

A nic1 = "Wi-Fi adapter"

B mac1 = "00:1A:2B:3C:4D:5G"

C print("NIC:", nic1, mac1)

Question 2

A nic = "Ethernet card"

B macs_per_nic = 2

C print(nic, macs_per_nic)

Question 3

A nic_list = ["Wi-Fi", "Ethernet"]

B mac_count = len(nic_list) - 1

C print(mac_count)

Question 4

A pc = "Laptop"

B nic = "Wi-Fi adapter"

C mac = "3C:22:FB:10:9A:01"

D print(mac, "identifies", pc)

Question 5

A mac = "00:1A:2B:3C:4D:5E"

B ip = "192.168.1.20"

C mac_type = "network address"

D print(mac_type)

Answer Key

What a MAC address is

Section A: Quick Questions

A — Its network interface card (NIC)

B — Two, one for each NIC

B — It is a hardware address

A — Media Access Control

A — None, each NIC has a unique one

Section B: Match the Pairs

00:1A:2B:3C:4D:5E → An example MAC address: a unique hardware identifier for one network interface card (NIC)

Wi-Fi NIC + Ethernet NIC → Two NICs in one device, so the device has two MAC addresses

Each NIC has its own MAC address, so a laptop with Wi-Fi and Ethernet has two different ones → wifi_mac != ethernet_mac

A MAC address is a hardware address that belongs to the NIC, not a network address → MAC address -> NIC

laptop (Wi-Fi + Ethernet) = 1 MAC address → A MAC address belongs to a NIC, not to the whole device. A laptop with Wi-Fi and Ethernet has two NICs, so it has two MAC addresses.

MAC address = network address that changes on each network → A MAC address is a hardware address for one NIC. It does not depend on the network. An IP address is the network address.

Section C: Definitions

MAC address — A unique hardware address given to one network interface card (NIC). Each NIC has its own, so a device with Wi-Fi and Ethernet has two. It identifies the hardware, not the network.

Section D: Fill in the Blanks

nic1.mac ← "00:1A:2B:3C:4D:5E"

IF wifi.mac <> ethernet.mac THEN
   OUTPUT "Different hardware"
ENDIF

nics ← ["Wi-Fi", "Ethernet"]
macCount ← LENGTH(nics)

address ← "MAC"
OUTPUT "Hardware, not network"

wifiNIC.mac ← "00:1A:2B:3C:4D:5E"
ethNIC.mac ← "00:1A:2B:3C:4D:5F"
laptop.macCount ← 2

Section E: Spot the Error

B — A MAC address is written in hexadecimal, so each digit must be 0-9 or A-F. G is not a hexadecimal digit. The last pair should be 5E.

B — Each network interface card has exactly one MAC address, so macs_per_nic should be 1, not 2.

B — Every NIC has its own MAC address. A device with Wi-Fi and Ethernet has two NICs, so it has two MAC addresses. Subtracting 1 gives the wrong count; it should be len(nic_list).

D — A MAC address identifies one network interface card, not the whole device. The device can have several NICs. The line should print nic.

C — A MAC address is a hardware address belonging to the NIC. It is not a network address. The line should be mac_type = "hardware address".