Overview
A VLAN is a logical group of network devices that appear to be on the same LAN, regardless of their physical location. They are configured so that they can communicate as if they were attached to the same physical connection, when in fact they are located on a number of different LAN segments. VLANs can be configured with management software, such as the NMC-RX application, and are extremely flexible because they are based on logical, rather than physical, connections.
A VLAN permits multiplexing multiple IP and/or Point to Point Protocol over Ethernet (PPPoE) interfaces over a single physical Ethernet port. This multiplexing is accomplished through VLAN subinterfaces.
You can create VLAN interfaces and subinterfaces one at a time or you can create multiple interfaces at a time using the VLAN Services Configuration Wizard.
Figure 1 shows a basic VLAN protocol stack.
