User's Manual

Using Static NAT
Chapter 5: Managing Your Network 91
Using Static NAT
Static NAT (or One-to-One NAT) allows the mapping of Internet IP
addresses or address ranges to hosts inside the internal network.
This is useful if you want a computer in your private network to have its own
Internet IP address. For example, if you have both a mail server and a Web
server in your network, you can map each one to a separate Internet IP
address.
Static NAT rules do not imply any security rules. To allow incoming traffic
to a host for which you defined Static NAT, you must create an Allow rule.
When specifying firewall rules for such hosts, use the host’s internal IP
address, and not the Internet IP address to which the internal IP address is
mapped. For further information, see Creating Rules on page 112.
Note: Static NAT and Hide NAT can be used together.
Note: Safe@Office appliance supports Proxy ARP (Address Resolution
Protocol). When an external source attempts to communicate with such
a computer, the Safe@Office appliance automatically replies to ARP
queries with its own MAC address, thereby enabling communication. As
a result, the Static NAT Internet IP addresses appear to external
sources to be real computers connected to the WAN interface.