Figure 8-6 Nat Rule: Add (Napt Flavor) - ZyXEL Communications Prestige 623 series User Manual

Step 2. Select NAPT from the Rule Flavor drop-down list menu.
Step 3.
Enter a unique number to the rule in the Rule ID field for identification purposes.
The Rule ID determines the order in which rules are invoked (the lowest numbered 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. Once a data packet matches a rule, the data is acted upon according
to that rule and is not subjected to higher-numbered rules.
Step 4. From the IFName drop-down list, select the interface on the Prestige to which this rule applies.
Typically, NAT rules apply to communication between your LAN and the Internet. Because the
device uses the WAN interface (which may be named ppp-0 or eoa-0 in the Web Configurator)
to connect your LAN to your ISP, it is the usual IF Name selection.
Step 5.
In the IFName drop-down list, select a protocol to which this rule applies, or choose ALL.
This selection specifies which type of Internet communication will be subject to this translation
rule. You can select ALL if the rule applies to all data.
By associating a protocol with this type of NAT rule, you ensure that all data using that protocol
is sent to the Internet referencing the public Internet address as the source computer. However,
data packets that use protocols not specified here will not undergo translation; their packet
headers will reflect the true source address of the LAN computer (and, because they contain
private IP addresses, these packets will not be routable on the Internet).
Step 6. In the Local Address From field and Local Address To fields, type the starting and ending IP
addresses, respectively, of the range of private addresses you want to be translated. Or type the
same address in both fields to specify a single value.
Configuring Network Address Translation

Figure 8-6 NAT Rule: Add (NAPT flavor)

Prestige 623 Series Dual-link ADSL Router
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