3Com 3C16111 - SuperStack 3 Firewall Web Site Filter, Руководство пользователя

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Setting up One-to-One NAT 119
LAN
The IP Address and Subnet on the Firewall’s LAN port are shown at the
top of the window. See “Specifying the LAN Settings” on page 57 to
change these settings.
DMZ/WAN
The IP addresses of the DMZ, if appropriate, and WAN ports are shown.
These differ from that of the LAN port if NAT is enabled. See “Specifying
the WAN/DMZ Settings” on page 58 to change these settings.
Add Route
Type the destination network of the router in the Dest. Network box, and
the IP address of the router as it appears on Firewall’s subnet in the
Gateway box. From the Link drop-down list, select the port on the
Firewall, LAN or WAN , that the router is connected to. You may have to
check the configuration of the LAN routers in order to find this
information.
Click Update to send the configuration data to the Firewall.
Setting up
One-to-One NAT
One-to-One NAT creates a relationship which maps valid external
addresses to internal addresses hidden by NAT. Machines with an internal
address may be accessed at the corresponding external valid IP address.
To create this relationship between internal and external addresses,
define internal and external address ranges of equal length. Once you
have defined that relationship, the machine with the first internal address
is accessible at the first IP address in the external address range, the
second machine at the second external IP address, and so on.
Consider a LAN for which the ISP has assigned the IP address range from
209.19.28.16
to
209.19.28.31
, with
209.19.28.16
used as the NAT
Public Address. You have configured the address range of
192.168.1.1
to
192.168.1.255
to be used for the machines on the LAN. Typically, only
machines that have been designated as Public LAN Servers are accessible
from the Internet. However, with One-to-One NAT, the machines with the
internal IP addresses of
192.168.1.2
to
192.168.1.16
can be made
accessible at the corresponding external IP address, as shown in Table 4.
DUA1611-0AAA02.book Page 119 Thursday, August 2, 2001 4:01 PM