Virtual Local Area Network (VLAN)
At work recently, there has been a lot of new deployments and I have had the opportunity to look at a lot of network diagrams. I've understood the OSI model Layer 2 with ease, and most of Layer 3 information made sense to me with the exception of VLANs. Here's a summary of what I understood about VLANs and what I learned in my pursuit to understand the networking diagrams. UPDATE : VLANs come under Layer 2 -> Why? Glad you asked. At Layer 2, we have no way of securing traffic, if anybody snoops the traffic, they get the frames with all our data encapsulated, so the best way to secure our traffic is to prevent the 'snoopers' from seeing our traffic in the first place. One way to do this is to restrict the 'broadcast domains' but this does not scale well so an alternative option (not a replacement, just an alternative) is to use VLANs. VLANs segment traffic into separate broadcast domains. There are two types of ports that are using on a Switch for working wi...