VLAN (virtual local area network) allows multiple LANs to share the same infrastructure (switches and interlinks) whilst remaining independent (i.e. providing multiple independent LANs in a virtual way)
VLAN subnets allow the FireBrick to operate with an external VLAN tagging network switch.
Use FireBrick to route and filter traffic between groups of ports on the VLAN switch
Use VLAN switch to effectively expand number of ports available to FireBrick
Ideal for a serviced office - can provide up to 30 VLAN subnets (with Extras Feature)
FireBrick DHCP Server can allocate addresses according to VLAN tag of requesting machine
Notes
More information can be found in the on-line Manual.
The FireBrick protects your network from attacks at the IP level, but is only as good as you configure it to be.
It is not a substitute for regular virus checking as viruses can arrive by a number of methods (web, email, zipped files, word documents, floppy disks, etc)
Whilst the FireBrick is a well establish product with many years of use in the field, it is constantly being enhanced with new features and improvements. As such these specifications are subject to change without notice.