ZyWALL 35 User’s Guide
Chapter 17 Network Address Translation (NAT)
295
C
H A P T E R
17
Network Address Translation
(NAT)
This chapter discusses how to configure NAT on the ZyWALL.
17.1 NAT Overview
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 is changed to a different IP address known within another network.
17.1.1 NAT Definitions
Inside/outside denotes where a host is located relative to the ZyWALL. For example, the
computers of your subscribers are the inside hosts, while the web servers on the Internet are
the outside hosts.
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.
Note that inside/outside refers to the location of a host, while global/local refers to the IP
address of a host used in a packet. Thus, an inside local address (ILA) is the IP address of an
inside host in a packet when the packet is still in the local network, while an inside global
address (IGA) is the IP address of the same inside host when the packet is on the WAN side.
The following table summarizes this information.
Note:
NAT never changes the IP address (either local or global) of an
outside
host.
Table 97
NAT Definitions
TERM
DESCRIPTION
Inside
This refers to the host on the LAN.
Outside
This refers to the host on the WAN.
Local
This refers to the packet address (source or destination) as the packet travels on the LAN.
Global
This refers to the packet address (source or destination) as the packet travels on the
WAN.
Содержание ZyXEL ZyWALL 35
Страница 1: ...ZyWALL 35 Internet Security Appliance User s Guide Version 3 64 3 2005 ...
Страница 2: ......
Страница 38: ...ZyWALL 35 User s Guide 36 ...
Страница 46: ...ZyWALL 35 User s Guide 44 ...
Страница 74: ...ZyWALL 35 User s Guide 72 Chapter 2 Introducing the Web Configurator ...
Страница 90: ...ZyWALL 35 User s Guide 88 Chapter 3 Wizard Setup ...
Страница 100: ...ZyWALL 35 User s Guide 98 Chapter 4 LAN Screens ...
Страница 106: ...ZyWALL 35 User s Guide 104 Chapter 5 Bridge Screens ...
Страница 128: ...ZyWALL 35 User s Guide 126 Chapter 6 Wireless LAN ...
Страница 135: ...ZyWALL 35 User s Guide Chapter 7 WAN Screens 133 Figure 47 General ...
Страница 152: ...ZyWALL 35 User s Guide 150 Chapter 7 WAN Screens Figure 57 Dial Backup Setup ...
Страница 158: ...ZyWALL 35 User s Guide 156 Chapter 7 WAN Screens ...
Страница 166: ...ZyWALL 35 User s Guide 164 Chapter 8 DMZ Screens ...
Страница 188: ...ZyWALL 35 User s Guide 186 Chapter 10 Firewall Screens Figure 75 Creating Editing A Firewall Rule ...
Страница 193: ...ZyWALL 35 User s Guide Chapter 10 Firewall Screens 191 Figure 80 My Service Rule Configuration ...
Страница 234: ...ZyWALL 35 User s Guide 232 Chapter 13 Introduction to IPSec ...
Страница 246: ...ZyWALL 35 User s Guide 244 Chapter 14 VPN Screens Figure 116 VPN Rules IKE Gateway Policy Edit ...
Страница 252: ...ZyWALL 35 User s Guide 250 Chapter 14 VPN Screens Figure 117 VPN Rules IKE Network Policy Edit ...
Страница 275: ...ZyWALL 35 User s Guide Chapter 15 Certificates 273 Figure 129 My Certificate Details ...
Страница 294: ...ZyWALL 35 User s Guide 292 Chapter 16 Authentication Server Figure 140 Local User Database ...
Страница 314: ...ZyWALL 35 User s Guide 312 Chapter 17 Network Address Translation NAT ...
Страница 318: ...ZyWALL 35 User s Guide 316 Chapter 18 Static Route ...
Страница 324: ...ZyWALL 35 User s Guide 322 Chapter 19 Policy Route ...
Страница 340: ...ZyWALL 35 User s Guide 338 Chapter 20 Bandwidth Management ...
Страница 376: ...ZyWALL 35 User s Guide 374 Chapter 22 Remote Management ...
Страница 390: ...ZyWALL 35 User s Guide 388 Chapter 24 Logs Screens Figure 198 Log Settings ...
Страница 413: ...ZyWALL 35 User s Guide Chapter 25 Maintenance 411 Figure 220 Restart Screen ...
Страница 414: ...ZyWALL 35 User s Guide 412 Chapter 25 Maintenance ...
Страница 440: ...ZyWALL 35 User s Guide 438 Chapter 28 WAN and Dial Backup Setup ...
Страница 456: ...ZyWALL 35 User s Guide 454 Chapter 31 DMZ Setup ...
Страница 460: ...ZyWALL 35 User s Guide 458 Chapter 32 Route Setup ...
Страница 470: ...ZyWALL 35 User s Guide 468 Chapter 33 Remote Node Setup ...
Страница 522: ...ZyWALL 35 User s Guide 520 Chapter 39 System Information Diagnosis ...
Страница 538: ...ZyWALL 35 User s Guide 536 Chapter 40 Firmware and Configuration File Maintenance ...
Страница 550: ...ZyWALL 35 User s Guide 548 Chapter 42 Remote Management ...
Страница 558: ...ZyWALL 35 User s Guide 556 Chapter 43 IP Policy Routing ...
Страница 574: ...ZyWALL 35 User s Guide 572 Chapter 45 Troubleshooting Figure 364 Java Sun ...
Страница 602: ...ZyWALL 35 User s Guide 600 Appendix C IP Subnetting ...
Страница 608: ...ZyWALL 35 User s Guide 606 Appendix E PPTP ...
Страница 626: ...ZyWALL 35 User s Guide 624 Appendix G Triangle Route ...
Страница 656: ...ZyWALL 35 User s Guide 654 Appendix J Importing Certificates ...
Страница 658: ...ZyWALL 35 User s Guide 656 Appendix K Command Interpreter ...
Страница 664: ...ZyWALL 35 User s Guide 662 Appendix L Firewall Commands ...
Страница 668: ...ZyWALL 35 User s Guide 666 Appendix M NetBIOS Filter Commands ...
Страница 674: ...ZyWALL 35 User s Guide 672 Appendix O Brute Force Password Guessing Protection ...
Страница 696: ...ZyWALL 35 User s Guide 694 Appendix Q Log Descriptions ...