ZyXEL Communications Intelligent Broadband Sharing Gateway P-324 - Manual (Page 130)

Prestige 324 Intelligent Broadband Sharing Gateway
NAT 11-15
Table 11-6 Menu 15.1.1.1 — Editing/Configuring an Individual Rule in a Set
FIELD DESCRIPTION EXAMPLE
Once you have finished configuring a rule in this menu, press [ENTER] at the message “Press ENTER to
Confirm…” to save your configuration, or press [ESC] to cancel.
When you configure One-to-One and Many-One-to-One mapping rules, the firewall
automatically allows traffic originating from the WAN to be forwarded to the LAN
IP address(es) of the computers specified in those rules. These computers do not
have firewall protection in this case.
11.3.2 Port Forwarding Setup
A NAT server set is a list of inside (behind NAT on the LAN) servers, for example, web or FTP, that you
can make visible to the outside world even though NAT makes your whole inside network appear as a
single machine to the outside world.
Use Menu 15 - NAT Setup to forward incoming service requests to the server(s) on your local network.
You may enter a single port number or a range of port numbers to be forwarded, and the local IP address of
the desired server. The port number identifies a service; for example, web service is on port 80 and FTP on
port 21. In some cases, such as for unknown services or where one server can support more than one
service (for example both FTP and web service), it might be better to specify a range of port numbers.
Entry 12 (port 1026) is non-editable (see Figure 11-10).
In addition to the servers for specified services, NAT supports a default server. A service request that does
not have a server explicitly designated for it is forwarded to the default server. If the default is not defined,
the service request is simply discarded.
When you configure NAT port forwarding rules, the firewall automatically allows
traffic originating from the WAN to be forwarded to the LAN IP address(es) of the
computers specified. These computers do not have firewall protection in this
case.
The most often used port numbers are shown in the following table. Please refer to RFC 1700 for further
information about port numbers and refer to the included disk for more examples and details on NAT.