ZyXEL Communications ZYWALL USG 2000 Manual page 293

In order for the server to be accessible to people from the Internet (WAN zone),
you need to create a 1:1 NAT mapping from the public IP address to the server's
private one.
The firewall is enabled, so you also need to create a rule to allow traffic in from the
WAN zone.
Figure 175 NAT 1:1 Example Network Topology
192.168.1.21
NAT 1:1 Address Objects
Use Object > Address > Add to create address objects for the private and public
IP addresses (LAN_SMTP and WAN_EG) as shown next.
Figure 176 Create Address Objects
NAT 1:1 Virtual Server
This section sets up a virtual server rule that changes the destination of SMTP
traffic coming to IP address 1.1.1.1 at the ZyWALL's ge3 interface, to the LAN
ZyWALL USG 2000 User's Guide
LAN
Chapter 16 Virtual Servers
ge2: 1.1.1.1
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