May 24, 2021

What is a Virtual Local Area Network (VLAN)

You may have heard the word VLAN before when people are talking about computer networks, either home, small offices or big business networks.

To understand what a VLAN is, firstly we’ll have to understand what a LAN is:

By definition:

Lan stands for “Local Area Network”. A LAN is a network of connected devices that exist within a specific location. You cand find LANs in homes, offices, educational institution, or other areas. A LAN may be wired, wireless, or a combination of the two. A standard wired LAN uses Ethernet to connect devices together.

Wireless LANs are typically created using a Wi-Fi signal. If a router supports both Ethernet and Wi-Fi connections, it can be used to create a LAN with both wired and wireless devices.

(Definition From TechTerms)

In other words, a LAN is a group of devices interconnected on the same network, on the same physical location.

What is a VLAN

Devices on the same network…

Can communicate with each other and share resources such as folders or printers without the need of an additional device like a router.

For example, imagine a home network consisting of a router, a switch, an access point, two computers and a printer all on the same LAN. If you don’t configure the network properly, anyone who connects to it either through the switch or the access point will have access to the network resources.

After accessing the network, the user will have the power of editing, deleting, or stealing your information, all of this is possible because all of the devices are located on the same network.

If we had a similar situation happening in a big business network, with thousands of computers and confidential information, the damage caused would be catastrophic.

On the other hand, If we configure VLANs in our network, we can create one for our home network, with our devices, and an additional one for Guests and configure it in a way that they only have access to the internet. If they wanted to scan the network for possible targets, they wouldn’t be able to because they will be in a different network.

In a company network, you can set VLANs per department (Accountant, IT, Students, Staff, etc) to increase security. A guest VLAN can also be created for the Guest WiFi network.

Security is not the only advantage VLANs provide, to mention a few we have:

  • It solves broadcasting problems.

  • VLAN reduces the size of broadcast domains.

  • It can make device management simple and easier.

  • You can make a logical grouping of devices by function rather than location.

  • It allows you to create groups of logically connected devices that act like they are on their network.

  • You can logically segment networks based on departments, project teams, or functions.

  • VLAN helps you to geographically structure your network to support the company’s scalability.

  • Higher performance and reduced latency.

  • VLANs provide increased performance.

  • Users may work on sensitive information that must not be viewed by other users.

  • VLAN removes the physical boundary.

  • It lets you easily segment your network.

  • It helps you to enhance network security.

  • You can keep hosts separated by VLAN.

  • You do not require additional hardware and cabling, which helps you to save costs.

  • It reduces the number of devices for a particular network topology.

  • VLAN makes managing physical devices less complex.

(Extracted from Guru 99)

As we have seen, there are significant advantages to your network when configuring VLANs apart from better security, and should definitely consider implementing those on your network.

Article written by: Giuseff Rivas.