Switch Features 73
Guest VLAN
The Guest VLAN feature allows a switch to provide a distinguished service to 
unauthenticated users. This feature provides a mechanism to allow visitors 
and contractors to have network access to reach external network with no 
ability to browse information on the internal LAN.
For information about configuring the Guest VLAN see "Configuring Port 
and System Security" on page 469.
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.