User Manual Part 1

Using Network Objects
Chapter 6: Managing Your Network 185
Using Network Objects
You can add individual computers or networks as network objects. This enables you to
configure various settings for the computer or network represented by the network object.
You can configure the following settings for a network object:
• Static NAT (or One-to-One NAT)
Static 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 Using
Rules on page 360.
Note: Static NAT, Hide NAT, and custom NAT rules can be used together.
Note: The 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.