Quick Reference Guide

ProSafe Wireless-N VPN Firewall SRXN3205 Reference Manual
Connecting to the Internet (WAN) 2-11
v1.0, January 2010
Configuring the WAN Mode
To access the WAN Mode, click on Network Configuration > WAN Settings and select the WAN
Mode tab. The WAN Mode screen displays.
The WAN Mode screen allows you to configure how your firewall uses the external Internet
connection. This screen gives you two choices for accessing the external Internet connection.
• Network Address Translation (NAT). This technique allows several computers on a LAN to
share the same Internet connection (IP address) while using private IP address on the LAN,
which are hidden from the Internet.
• Classical Routing. This method allows the firewall to perform the routing, but requires
separate valid static Internet IP address for each PC on your LAN.
Network Address Translation
Network Address Translation (NAT) allows all PCs on your LAN to share a single public Internet
IP address. From the Internet, there is only a single device (the VPN firewall) and a single IP
address. PCs on your LAN can use any private IP address range, and these IP addresses are not
visible from the Internet.
• The VPN firewall uses NAT to select the correct PC (on your LAN) to receive any incoming
data.
• If you only have a single public Internet IP address, you MUST 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 PCs, and you can map incoming traffic on
the other public IP addresses to specific PCs on your LAN. This one-to-one inbound mapping
is configured using an inbound firewall rule.
Figure 2-10