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AMG1202-T10A User’s Guide
127
C
HAPTER
9
Network Address Translation (NAT)
9.1 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.
9.1.1 What You Can Do in the NAT Screens
• Use the
NAT General Setup
screen (
) to configure the NAT setup
settings.
• Use the
Port Forwarding
screen (
) to configure forward incoming
service requests to the server(s) on your local network.
• Use the
Address Mapping
screen (
) to change your ZyXEL Device’s
address mapping settings.
• Use the
ALG
screen (
) to enable and disable the SIP (VoIP) ALG in the
ZyXEL Device.
9.1.2 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.
NAT
In the simplest form, NAT changes the source IP address in a packet received from a subscriber
(the inside local address) to another (the inside global address) before forwarding the packet to the
WAN side. When the response comes back, NAT translates the destination address (the inside
global address) back to the inside local address before forwarding it to the original inside host.
Summary of Contents for AMG1202-T10A
Page 2: ......
Page 6: ...Document Conventions AMG1202 T10A User s Guide 6 Server Firewall Telephone Router Switch ...
Page 8: ...Safety Warnings AMG1202 T10A User s Guide 8 ...
Page 10: ...Contents Overview AMG1202 T10A User s Guide 10 ...
Page 18: ...Table of Contents AMG1202 T10A User s Guide 18 ...
Page 19: ...19 PART I User s Guide ...
Page 20: ...20 ...
Page 26: ...Chapter 1 Introduction AMG1202 T10A User s Guide 26 ...
Page 32: ...Chapter 2 The Web Configurator AMG1202 T10A User s Guide 32 ...
Page 36: ...Chapter 3 Status Screens AMG1202 T10A User s Guide 36 ...
Page 53: ...53 PART II Technical Reference ...
Page 54: ...54 ...
Page 84: ...Chapter 6 WAN Setup AMG1202 T10A User s Guide 84 ...
Page 96: ...Chapter 7 LAN Setup AMG1202 T10A User s Guide 96 ...
Page 126: ...Chapter 8 Wireless LAN AMG1202 T10A User s Guide 126 ...
Page 142: ...Chapter 10 Firewall AMG1202 T10A User s Guide 142 ...
Page 148: ...Chapter 11 Filters AMG1202 T10A User s Guide 148 ...
Page 152: ...Chapter 12 Static Route AMG1202 T10A User s Guide 152 ...
Page 158: ...Chapter 13 802 1Q 1P AMG1202 T10A User s Guide 158 ...
Page 166: ...Chapter 14 Quality of Service QoS AMG1202 T10A User s Guide 166 ...
Page 202: ...Chapter 19 Logs AMG1202 T10A User s Guide 202 ...
Page 223: ...Chapter 23 Product Specifications AMG1202 T10A User s Guide 223 ...
Page 224: ...Chapter 23 Product Specifications AMG1202 T10A User s Guide 224 ...
Page 264: ...Appendix C Pop up Windows JavaScripts and Java Permissions AMG1202 T10A User s Guide 264 ...
Page 278: ...Appendix D Wireless LANs AMG1202 T10A User s Guide 278 ...
Page 286: ...Appendix F Legal Information AMG1202 T10A User s Guide 286 ...
Page 294: ...Index AMG1202 T10A User s Guide 294 ...