Virtual LAN and virtual MAC support
Virtual LAN (VLAN) technology is becoming more important in network planning for many customers. A VLAN is a configured logical grouping of nodes that uses switches. Nodes on a VLAN can communicate as though they were on the same LAN.
You need a switch to communicate across VLANs, but typically separate VLANs are in separate IP subnets; therefore, you often need a router to communicate across VLANs.
Virtual Medium ...