IT Support 101: What is VLAN?
Updated: May 20
Would you like to learn more about VLANs?
What is VLAN?
The movie Inception, if you have heard of it, depicts the ability of a group of people to enter the dreams of others. They also illustrate in the movie the ability to not only enter a dream but to enter a dream within a dream. If you want it simply explained, a VLAN or Virtual Local Area Network is a network inside another network. The definition of a network inside a network is not entirely correct, of course; it is more of a network within a network that runs in parallel of the leading network. Say there is a VLAN configuration in your office for the accounts team, but the rest of the office directly connects to the router. However, for the accounts team, it would appear that their network does not contain any of your computers, only their other account staff terminals, the switcher where the VLAN configured on the second layer and the router itself. This scenario is a hypothetical one, of course, generally, in such large organizations, every department placed within their specific VLAN.
Primarily, VLAN acts as a security feature, but one should never assume having a VLAN would make your network secure. Say your HR and accounts department are on separate VLANs, this does prevent terminals within the respective departments from listening to the packets being sent or broadcasted by the other. But it does not mean categorically secure and blocks any malicious attempts from an attacker which has compromised a computer within either terminal. Security aside, VLAN is also mostly an administrative feature, allowing network administrators to easily configure group policies via VLAN as opposed to individual or groups of the computer. So rather than adding and removing computers in a department, whatever terminal used in an environment can be grouped entirely and administrated as a group.
Performance is another great advantage of setting up VLANs in your organization. Because each group of VLAN disregards or does not receive any broadcast messages or pieces of information from other VLAN, this significantly reduces bottlenecks and lays out a clearer path for your traffic to take. Typically, to contain traffic, you have to deploy extra routers to prevent information from being broadcasted everywhere. A router acts as a point of information collection at this point, but deploying so many routers would be a waste of resources. VLAN is an excellent workaround as it reduces the need for additional hardware and substantially reduces traffic as a whole inside your network environment. Less traffic means fewer interruptions and improved performance.
VLAN configurations used to be tedious, it still is, settings are complicated, and mistakes can often be made, which is why professional IT technicians are required to install these sophisticated switchers and administrate the settings for VLANs with the respective ports. Which has changed over the years with many smart switches, rather than using CLI or Command-line interface, you can plug the smart switcher, plug everything in and administrate the settings with a very easy-to-use web interface accessed via your local IP. GUI is straightforward, for an IT Technician, not necessarily for a layman. A unique and specialized understanding of how VLANs work and set up is a must. You need to have a great understanding of IPv4 and special-purpose address reserved for the private network from IANA. But that is another time for another blog.
We hope you learned a little more about what VLANs through this article, thank you for reading 'IT Support 101: What is VLAN?' by IT Block. IT Block is an IT support services provider based in Singapore and we love sharing our IT expertise with the rest of the world. #IT #support #singapore #VLAN #services