ZyXEL Communications 2 Plus User Manual

 Chapter 17 Network Address Translation (NAT)

ZyWALL 2 Plus User’s Guide

• Server: This type allows you to specify inside servers of different services behind the 

NAT to be accessible to the outside world although, it is highly recommended that you use 
the DMZ port for these servers instead.

"

Port numbers do not change for One-to-One and Many-One-to-One NAT 
mapping types. 

The following table summarizes the NAT mapping types.

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You must create a firewall rule in addition to setting up SUA/NAT, to allow 
traffic from the WAN to be forwarded through the ZyWALL.

SUA (Single User Account) is a ZyNOS implementation of a subset of NAT that supports two 
types of mapping, Many-to-One and Server. The ZyWALL also supports Full Feature NAT 
to map multiple global IP addresses to multiple private LAN IP addresses of clients or servers 
using mapping types. Select either SUA or Full Feature in NAT Overview. 

Table 94   NAT Mapping Types

One-to-One

ILA1 IJ IGA1

1-1

Many-to-One (SUA/PAT)

ILA1 IJ IGA1
ILA2 IJ IGA1
…

M-1

Many-to-Many Overload

ILA IJ IGA1
ILA2 IJ IGA2
ILA3 IJ IGA1
ILA4 IJ IGA2
…

M-M Ov

Many-One-to-One

ILA1 IJ IGA1
ILA2 IJ IGA2
ILA3 IJ IGA3
…

M-1-1

Server

Server 1 IP IJ IGA1
Server 2 IP IJ IGA1
Server 3 IP IJ IGA1

Server