Still Confused About VLAN? Let’s Clear It Up
You’ve probably heard the term VLAN tossed around in networking conversations, and it might sound technical—but it’s actually pretty straightforward.
Think of a VLAN (Virtual Local Area Network) as a way to split one physical network switch into separate, isolated groups. Imagine you’ve got an 8-port TP-Link or Netgear switch at home. By default, every device plugged into it can talk to every other device.
Now here’s where VLANs come in: you create virtual “walls” between some of those ports. So maybe ports 1–4 are for your work devices, and ports 5–8 are for your smart home gadgets. Even though they’re on the same switch, they can’t see or interfere with each other unless you allow it.
It’s like having two networks in one box—clean, organized, and much more secure.
A. Quick Real-Life Scenario
Let’s say your setup looks like this:
- VLAN 10: Tech PC, Work-from-home systems
- VLAN 20: IoT devices, Smart TV
- VLAN 30: IP Cameras
- VLAN 40: Guest Wi-Fi users
Now, you’re wiring this to a managed switch (like TL-SG108E), and here’s how you configure the ports:
Port | Connected Device | VLAN | Type |
---|---|---|---|
1 | TP-Link ER605 Router | 10,20,30,40 | Tagged (Trunk) |
2 | Work PC | 10 | Untagged |
3 | CCTV Camera 1 | 30 | Untagged |
4 | Smart TV | 20 | Untagged |
5 | Deco Mesh Node | 10,20,40 | Tagged (Trunk) |
Tagged means this port carries multiple VLANs, usually used when connecting to routers or mesh nodes.
Untagged means the device on this port is assigned to a single VLAN, like your TV or IP cam. The device doesn’t need to know VLAN stuff—it just connects and works.
B. Some Ground Rules You Must Know
- Never mix tagged and untagged on the same VLAN ID—you’ll cause mayhem.
- Access Points need tagged trunks if you want to push multiple SSIDs (like Guest, Home, IoT).
- Always assign a dedicated VLAN for CCTV if you want peace of mind (and uninterrupted Netflix).