Network Address Translation (Nat); Overview; What You Can Do In The Nat Screens; What You Need To Know About Nat - ZyXEL Communications P-660HN User Manual

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H A P T E R
Network Address Translation

8.1 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.

8.1.1 What You Can Do in the NAT Screens

• Use the NAT General Setup screen
settings.
• Use the Port Forwarding screen
incoming service requests to the server(s) on your local network.
• Use the Address Mapping screen
Device's address mapping settings.
• Use the SIP ALG screen
ALG in the ZyXEL Device.

8.1.2 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.
Global/Local
Global/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 global address refers to the IP address of the host when the same packet is
traveling in the WAN side.
P-660HN-Fx User's Guide
(Section 8.2 on page
(Section 8.3 on page
(Section 8.4 on page
(Section 8.5 on page 143) to enable and disable the SIP (VoIP)
8
(NAT)
136) to configure the NAT setup
137) to configure forward
140) to change your ZyXEL
135