Prestige 310 Broadband Sharing Gateway
6-12
Network Address Translation (NAT)
Table 6-6 Menu 15.1.1.1 — Editing/Configuring an Individual Rule in a Set
FIELD
DESCRIPTION
EXAMPLE
Type
Press [SPACE BAR] to toggle through a total of five types. These
are the mapping types discussed in
Table 6-2.
Server
allows you to
specify multiple servers of different types behind NAT to this
computer. See
section 6.5.3
for an
example.
One-to-One
Local IP
Only local IP fields are
N/A
for server; Global IP fields MUST be set
for
Server
.
Start
This is the starting local IP address (ILA).
0.0.0.0
End
This is the ending local IP address (ILA). If the rule is for all local IPs,
then put the Start IP as 0.0.0.0 and the End IP as 255.255.255.255.
This field is
N/A
for One-to-One and Server types.
N/A
Global IP
Start
This is the starting global IP address (IGA). If you have a dynamic
IP, enter 0.0.0.0 as the
Global IP Start
. Note that
Global IP Start
can be set to 0.0.0.0 only if the types are
Many-to-One
or
Server
.
0.0.0.0
End
This is the ending global IP address (IGA). This field is
N/A
for
One-
to-One
,
Many-to-One
and
Server types
.
N/A
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.
6.4 NAT Server Sets – Port Forwarding
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 6-10
).
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.
