12.1 IP addresses, MAC addresses and the ARP process
In this section you will briefly recap MAC and IP addresses, look at where they fit into the TCP/IP network model, and how the addresses interact with each other. You will use a small network set up in Packet Tracer running in simulation mode, which will show you what the packets and frames of data are doing at each stage of the process.
Watch the video below, which is about 6 minutes long.
Activity 1 Test yourself
1. What is the Network Access layer protocol data unit (PDU) called?
The correct answer is b.
2. What is the purpose of the ARP cache?
(a) The ARP cache records the number of ICMP packets sent.
(b) It is an address table.
(c) The ARP cache stores the IP address to MAC address mappings temporarily to minimise ARP lookups.
(d) The ARP cache stores a history of destination IP addresses the machine has communicated with.
The correct answer is c.