ZyXEL Communications 2 Plus User Manual

Chapter 17 Network Address Translation (NAT)

ZyWALL 2 Plus User’s Guide

Selecting SUA means (latent) multiple WAN-to-LAN and WAN-to-DMZ address translation. 
That means that computers on your DMZ with public IP addresses will still have to undergo 
NAT mapping if you’re using SUA NAT mapping. If this is not your intention, then select 
Full Feature NAT and don’t configure NAT mapping rules to those computers with public 
IP addresses on the DMZ.

Click ADVANCED > NAT to open the NAT Overview screen. 

Figure 218   ADVANCED > NAT > NAT Overview

The following table describes the labels in this screen.  

Table 95   ADVANCED > NAT > NAT Overview

NAT Setup

Max. 

Concurrent 

Sessions 

This read-only field displays the highest number of NAT sessions that the ZyWALL 

will permit at one time.

Max. 

Concurrent 

Sessions Per 

Host

Use this field to set the highest number of NAT sessions that the ZyWALL will permit 

a host to have at one time.

Enable NAT

Select this check box to turn on the NAT feature for the WAN port. Clear this check 

box to turn off the NAT feature for the WAN port.

Address 

Mapping Rules

Select SUA if you have just one public WAN IP address for your ZyWALL. This lets 

the ZyWALL use its permanent, pre-defined NAT address mapping rules. 
Select Full Feature if you have multiple public WAN IP addresses for your ZyWALL. 

This lets the ZyWALL use the address mapping rules that you configure. This is the 

equivalent of what used to be called full feature NAT or multi-NAT.
The bar displays how many of the ZyWALL's possible address mapping rules are 

configured. The first number shows how many address mapping rules are 

configured on the ZyWALL. The second number shows the maximum number of 

address mapping rules that can be configured on the ZyWALL.