ZyXEL Communications P-660R-11V3 User Manual

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P-660R-T1 v3 User’s Guide
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 10 
Network Address Translation
(NAT)
10.1  Overview
This chapter discusses how to configure NAT on the ZyXEL Device. NAT (Network Address 
Translation - NAT, RFC 1631) is the translation of the IP address of a host in a packet, for 
example, the source address of an outgoing packet, used within one network to a different IP 
address known within another network.
10.1.1  What You Can Do in the NAT Screens
• Use the NAT screen (
) to configure the NAT settings.
• Use the DMZ screen (
) to configure the DMZ settings.
• Use the Virtual Server screen (
requests to the server(s) on your local network. 
• Use the IP Address Mapping screen (
to change your ZyXEL 
Device’s address mapping settings.
10.1.2  What You Need To Know About NAT
Inside/Outside
Inside/outside denotes where a host is located relative to the ZyXEL Device, for example, the 
computers of your subscribers are the inside hosts, while the web servers on the Internet are 
the outside hosts. 
Public/Local
Public/local denotes the IP address of a host in a packet as the packet traverses a router, for 
example, the local address refers to the IP address of a host when the packet is in the local 
network, while the public address refers to the IP address of the host when the same packet is 
traveling in the WAN side.