Best Data DSL542 ADSL Ethernet Router User’s Guide
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Click the NAT tab, then select NAT Rule Entry from the NAT Options drop-down list on the
right side of the page.
The NAT Rule entry page displays a row for each currently configured NAT rule.
1. Click to display the NAT Rule – Add page.
The NAPT flavor displays by default in the Rule Flavor drop-down list. The NAT Rule – Add
page displays, as shown in Figure .
Figure 25. NAT Rule – Add Page (napt Flavor)
2. Enter a Rule ID.
The Rule ID determines the order in which rules are invoked (the lowest numbere d rule is
invoked first, and so on). In some cases, two or more rules may be defined to act on the
same set of IP addresses. Be sure to assign the Rule ID so that the higher priority rules
are invoked before lower-priority rules. It is recommended that you select rul e IDs as
multiples of 5 or 10 so that, in the future, you can insert a rule between two exis ting rules.
Once a data packet matches a rule, the data is acted upon according to that rule and is
not subjected to higher-numbered rules.
3. From the IFName drop-down list, select the interface on the device to which this rule
applies.
Typically, NAT rules are used for communication between your LAN and the Internet.
Because the device uses the WAN interface (which may be named ppp-0 or eoa-0) to
connect your LAN to your ISP, it is the usual IFName selection.
4. In the Local Address From field and Local Address To fields, type the starting and
ending IP addresses, respectively, of the range of private address you want to be
translated. Or, type the same address in both fields to specify a single value.
To specify that data from all LAN addresses should be translated, type 0 (zero) in each
From field and 255 in each To field.
If you have several non-sequential private addresses, you can create an additional napt
rule for each address.
These addresses should correspond to private addresses already in use on your network
(either assigned statically to your PCs, or assigned dynamically using DHCP).
5. In the Global Address From and Global Address To fields, type the public IP address
assigned to you by your ISP.
If you have multiple WAN interfaces, in both fields type the IP address of the interface to
which this rule applies. This rule will not be enforced for data that arrives on other PPP
interfaces.
If you have multiple WAN interfaces and want the rule to be enforced on a range of th em,
type the starting and ending IP addresses of the range.