ZyXEL Communications WAH7130, Руководство пользователя

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WAH7130 User’s Guide
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H A P T E R
8
NAT
8.1 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.
The figure below is a simple illustration of a NAT network. You want to assign ports 21-25 to one
FTP, Telnet and SMTP server (
A in the example), port 80 to another ( B in the example) and assign
a default server IP address of 192.168.1.35 to a third ( C in the example).
You assign the LAN IP addresses to the devices ( A to C ) connected to your WAH7130. The ISP
assigns the WAN IP address. The NAT network appears as a single host on the Internet. All traffic
coming from
A to C going out to the Internet use the IP address of the WAH7130, which is
192.168.1.1.
Figure 29
NAT Example
This chapter discusses how to configure NAT on the WAH7130.
8.1.1 What You Can Do
• Use the General screen to view the NAT status ( Section 8.2 on page 57 ).
• Use the Port Forwarding screen to set a default server and change your WAH7130’s port
forwarding settings to forward incoming service requests to the server(s) on your local network
(
Section 8.3 on page 57 ).
A: 192.168.1.33
B: 192.168.1.34
C: 192.168.1.35
IP address
192.168.1.1
WAN/WWAN
LAN/WLAN
assigned by ISP
FTP, Telnet, SNMP
Port 80
Ports 21 to 25