Coyote Point Systems Equalizer GX Series, Administration Manual

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Outbound NAT:
NAT, or Network Address Translation, is a common concept for most network
administrators. Equalizer administrators usually need to enable NAT when a server on an
"internal" (non-public, DMZ) network needs to access resources on the Internet or another public
network. This internal network can be either a local network or a destination network for
Equalizer. In this scenario, the administrator enables outbound NAT and selects the local network
that should be used to NAT packets from the internal network. For example:
In this example, neither the 192.168.211.0/24 nor the 192.168.105.0/24 networks can access the
Internet directly. The administrator configures Equalizer to provide outbound NAT service for
these networks by using an IP address on the 10.0.0.0/24 network when these internal networks
need to talk to the Internet.
When configuring outbound NAT, the internal local network that is being configured for outbound
NAT must use the routing information for the external network which it is using NAT through. In
the example above, the default gateway for the 192.168.211.0/24 network will really be on the
10.0.0.0/24 network.
This is logical when you remember it this way: If Equalizer is sending a packet from the
192.168.211.0/24 network to a host on the Internet, it has to be sent through the gateway of the
external network, rather than the internal network.
When Outbound NAT is enabled for a local network that contains attached destination networks,
the destination networks automatically inherit the same outbound NAT configuration.
Note - Outbound NAT is not supported for IPv6.
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Equalizer Administration Guide