The ability to identify which layers pertain to a networking device gives a
troubleshooter the ability to minimize the complexity of a problem by dividing
the problem into manageable parts.
For instance,
knowing that Layer 3 issues are of no importance to a switch, aside from
multilayer switches, defines the boundaries of a task to Layer 1 and Layer 2.
Given the fact that there is still plenty to consider at only these two layers,
this knowledge can prevent the wasting of time troubleshooting irrelevant
possibilities and will significantly reduce the amount of time spent attempting
to correct a problem. It is important to note that there are network
applications that are part of these devices that move into Layers 4-7.