VLAN is a logical grouping of networking devices in the same broadcast domain. This logical separation is very beneficial in many cases. For example, if we have different geological locations, using VLANS could be a great way to group networking devices, even if they are in different places, but they act like one broadcast domain. This diagram illustrates a classic switching architecture; there is a specific switch for every specific enterprise department:
The following diagram illustrates the beneficial results of implementing VLANs. We can configure a switch for many different departments:
Switching operations occur in layer 2, but when we use VLANs, we need a router (layer 3) to make VLANs communicate with each other via an operation named interVLAN routing. VLAN trunking is needed to interconnect switches by tagging each frame with a VLAN ID, which is a number...