VLAN

A VLAN, or Virtual Local Area Network, is a logical grouping of network devices, typically located on one or more physical network switches, into a single broadcast domain. VLANs are created to provide network administrators with the ability to segment a large network into smaller, more manageable groups, improving network performance, security, and manageability.

In a VLAN, devices can communicate with each other as if they were on the same physical network, even if they are located on different physical switches. VLANs are configured by assigning ports on network switches to a particular VLAN, and traffic is then separated by VLAN tags, which are added to the Ethernet frame headers of each packet.