What Is VLAN – How Do I Create It?

April 8, 2011 / FAQs

What is a VLAN?
VLAN stands for Virtual Local Area Network.

Technically, VLAN or virtual LAN is a domain created for broadcast. Usually, this broadcast domain created by the router switch.
The administrator has to put some switch ports in a VLAN other than the default one. All the ports in one VLAN in a single broadcast domain.

How do I create a VLAN?
The configuration of VLANs depends on the different types of Cisco switches. However, the commands can differ but the objective remains the same:

  • Create new VLANs
  • Add every port in the correct VLAN

For eg, if we want to create VLANs 5 and 10, we will put ports 2 & 3 in VLAN 5 (Marketing) and ports 4 and 5 in VLAN 10 (Human Resources). If you are using a Cisco 2950 switch, you will have to follow the following procedure:

Now, there should be communication between only ports 2 and 3, and ports 4 & 5. This is so because each one of them is in itself a VLAN. To enable communication between devices located on port 2 and port 4, a trunk port needs to be configured to a router. It will then strip off the VLAN information, route the data packet, and add back the VLAN information to it.