VLANs break the rule that physical location determines network identity. Two devices on the same switch can be strangers; two devices across a building can be neighbors.
VLANs draw invisible walls through your physical network—isolating traffic, containing breaches, and letting you reorganize everything without touching a single cable.
How switches mark Ethernet frames with VLAN identity, allowing one physical cable to carry traffic for dozens of separate networks without mixing them up.
VLANs create isolation. Inter-VLAN routing creates controlled doors through those walls—through router-on-a-stick configurations or wire-speed Layer 3 switching.
Every network will eventually be breached somewhere. Segmentation determines whether that breach stays contained or spreads everywhere. Here's how to build the compartments.
Was this page helpful?