Virtual Local Area Networks (VLANs) provide security and create smaller broadcast domains by using software to create virtually separated subnets. The broadcast traffic from a node that is in a VLAN goes to all nodes that are members of the VLAN. Thus, VLANs reduce CPU use and increase security by restricting the traffic to a few nodes, instead of every node on the LAN.

Any end-system that performs VLAN functions and protocols is VLAN-aware. However, very few end-systems are VLAN-aware. VLAN-unaware switches cannot handle VLAN packets from VLAN-aware switches. Hence, Avaya gateways have VLAN configuration turned off by default. Create separate VLANs for VoIP applications.