Administrator Guide

Switch Feature Overview 83
The switch supports the Generic Attribute Registration Protocol (GARP).
GARP VLAN Registration Protocol (GVRP) relies on the services provided by
GARP to provide IEEE 802.1Q-compliant VLAN pruning and dynamic
VLAN creation on 802.1Q trunk ports. When GVRP is enabled, the switch
registers and propagates VLAN membership on all ports that are part of the
active spanning tree protocol topology.
For information about configuring GARP timers see "Layer-2 Multicast
Features " on page 867.
Voice VLAN
The Voice VLAN feature enables switch ports to carry voice traffic with a
configured priority. The priority level enables the separation of voice and data
traffic transiting the switch. Voice VLAN is the preferred solution for
enterprises wishing to deploy VoIP services in their network.
Guest VLAN
The Guest VLAN feature allows the administrator to provide service to
unauthenticated users, i.e., users that are unable to support 802.1X
authentication.
For information about configuring the Guest VLAN see "Port and System
Security " on page 623.
Unauthorized VLAN
The Unauthorized VLAN feature allows the administrator to configure a
VLAN for 802.1X-aware hosts that attempt authentication and fail.
Double VLANs
The Double VLAN feature (IEEE 802.1QinQ) allows the use of a second tag
on network traffic. The additional tag helps differentiate between customers
in the Metropolitan Area Networks (MAN) while preserving individual
customer’s VLAN identification when they enter their own 802.1Q domain.
NOTE: DVLAN is not available on the N3000 running the AGREGATION ROUTER
image.