WESM zl Management and Configuration Guide WT.01.28 and greater

8-34
Configuring Network Address Translation (NAT)
Configuring NAT
This setting, which is available only for destination NAT, allows you to configure
port forwarding. Choose the protocol for the application for which you are
creating the NAT definition. For example, if you are setting up destination NAT
to allow wireless stations to reach your Web server, select TCP.
5. In the Before Translation section, specify the IP address and port to the traffic
to be translated is destined.
a. In the Local Address field, enter the IP address to be translated.
This address depends on the choices that you made in the NAT section. Refer
to Table 8-5.
Table 8-7. Determining the IP Address for the Local Address Field
For destination NAT, the local address is actually the IP address of a host as
it appears to hosts in the opposite network. So if you are using destination
NAT to translate wireless requests to a wired server, enter the address known
in the wireless network (typically, the Wireless Edge Services zl Module’s).
b. In the Local Port field, enter the port to which the traffic to be translated is
destined. Specify a number from 1 through 65,535.
This setting is used for port forwarding and is available only when you select
Destination for the Address Type. See “Using Port Forwarding with Static
Destination NAT” on page 8-9 for more information.
For example, you are setting up NAT for traffic inbound from a public
wireless network to your internal FTP server. This traffic from the public
network is destined to port 21, so you enter 21 in the Local Port field.
6. In the After Translation section, specify how the Wireless Edge Services zl
Module should translate the IP header:
a. In the Global Address field, enter the IP address as it should appear after
translation. In other words, enter the actual IP address of the server to which
the traffic is destined.
See Table 8-6 for guidelines on specifying this address.
Interface Type Address Type IP Address for the Local Address Field
Inside (Private) Destination IP address of an outside device as it appears on the
inside network
Outside (Public) Destination IP address of an inside device as it appears on the
outside network