|  | 1.2 | Virtual LANs
| 1.2.1 | Introduction to VLANs
LANs are increasingly being divided into workgroups connected via common backbones to form virtual LAN (VLAN) topologies. VLANs logically segment the physical LAN infrastructure into different subnets (broadcast domains for Ethernet) so that broadcast frames are switched only between ports within the same VLAN. Initial implementations offered a port-mapping capability that established a broadcast domain between a default group of devices. Current network requirements demand VLAN functionality, which will cover the entire network. This approach to VLANs allows you to group geographically separate users in network-wide virtual topologies.