A VLAN is a Virtual Local Area Network. It’s a logical grouping of devices on a network, usually based on location or function. For example, all computers in a company Finance Department could be assigned to the “Finance” VLAN, while all computers in the company Administration Department could be assigned to the “Admin Lab” VLAN. In this way, VLANs can improve the efficiency and flexibility of a local area network.
A VLAN can advance security and performance by separating traffic on your network. It can also make it easier to administer your network by grouping devices that need similar setup.
A VLAN is created by adding a tag, or header, to each Ethernet frame. This tag tells the network which VLAN the frame should be sent to. Devices in different VLANs can’t see each other’s traffic unless associated to a router configured to allow it.
Administration – VLANs can make it easier to manage your network by grouping devices that require similar settings. For example, you can put all the devices in your sales department on the same VLAN. This way, you can easily apply the same security and performance settings to all the devices in that group.
Elasticity – VLANs can make it easier to add or remove devices from your network. For example, if you want to add a new device to your network, you can simply assign it to the appropriate VLAN. You don’t need to reconfigure your whole network.
Safety – By isolating traffic on different VLANs, you can prevent illegal users from interfering on network traffic.
Performance – VLANs can improve performance by dropping transmission traffic. Broadcast traffic is traffic sent to all devices on a network, regardless of whether they need it. By putting devices in different VLANs, you can reduce the amount of broadcast traffic your network has to deal with.