An IP address is the logical addressing scheme for nodes on a network. IP Addresses exist at the Network layer of the OSI Model and help facilitate the L3 goal of “end to end” delivery.
A MAC address is the physical addressing scheme for individual NIC cards on each node of a network. MAC addresses exist at the Data Link layer of the OSI Model and help facilitate the L2 goal of “hop to hop” delivery.
The Address Resolution Protocol (ARP) creates the correlation which makes the union between these two addressing schemes possible.
We’ve already discussed the basic functionality of ARP and its role in how packets move through a network. However, there are different iterations of address resolution – each employed at different times and for different situations.
This article series will discuss each of these iterations and the situations for which they are used.