Use this option to map an available IP address on the WAN side of the SimpleWAN device to a local IP address on your network. This is usually done through via a static IP block you have available from your ISP. Before setting up the 1:1 NAT in the Firewall section, please setup a proxy ARP in the interface that will be providing the IP. In other words, this is an external IP that is being setup at this time if it is the WAN or WAN2 interface. Go to the Interfaces option on the left navigation pane of the site, and click the appropriate interface that is providing the address. Then, click the plus “+” icon next to the Proxy ARP listing. Place the IP in the text input box on the following page , and add a description if you wish. Click save, and proceed to the Firewall's 1:1 NAT option.
Now that you have setup the proxy ARP, click Firewall in the navigation pane on the left-hand side, then click 1:1 NAT. If you don't see this option, please verify that you are in Advanced View by clicking Logged in as at the top right of the page when in Site Overview of the site in question. Next, specify the “Interface IP” and “Destination IP”. The Interface IP is the IP address on the router that will receive the traffic. This is commonly set up as a Proxy ARP address. The Destination IP is the IP address of the computer/server/other networked device that the traffic will be forwarded to. This is behind the SimpleWAN. To put it simply, you are assigning an external IP to an internal IP so that it appears as that external IP to the world. This is typically done of servers or other resources that you'd like a static external IP assigned to that is different than the static external IP of the SimpleWAN device.