IPv4 and IPv6 Internet and Broadband Settings
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ProSafe Wireless-N 8-Port Gigabit VPN Firewall FVS318N
Configure the IPv4 WAN Mode
By default, IPv4 is supported and functions in NAT mode but can also function in classical
routing mode. IPv4 functions the same way in IPv4-only mode that it does in IPv4 / IPv6
mode. The latter mode adds IPv6 functionality (see Configure the IPv6 Routing Mode on
page 38).

Network Address Translation

Network Address Translation (NAT) allows all computers on your LAN to share a single public
Internet IP address. From the Internet, there is only a single device (the wireless VPN
firewall) and a single IP address. Computers on your LAN can use any private IP address
range, and these IP addresses are not visible from the Internet.
Note the following about NAT:
•The wireless VPN firewall uses NAT to select the correct computer (on your LAN) to
receive any incoming data.
•If you have only a single public Internet IP address, you need to use NAT (the default
setting).
•If your ISP has provided you with multiple public IP addresses, you can use one address
as the primary shared address for Internet access by your computers, and you can map
incoming traffic on the other public IP addresses to specific computers on your LAN. This
one-to-one inbound mapping is configured using an inbound firewall rule.

Classical Routing

In classical routing mode, the wireless VPN firewall performs routing, but without NAT. To
gain Internet access, each computer on your LAN needs to have a valid static Internet IP
address.
If your ISP has allocated a number of static IP addresses to you, and you have assigned one
of these addresses to each computer, you can choose classical routing. Or you can use
classical routing for routing private IP addresses within a campus environment.
To view the status of the WAN ports, you can view the Router Status screen (see View the
System Status on page 356).

Configure the IPv4 Routing Mode

To configure the IPv4 routing mode:
1. Select Network Configuration > WAN Settings. The WAN Mode screen displays: