Using a Layered Architectural Model to Describe Data Flow
Position of network devices in layered model

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.