Dynalink RTA100+, User Manual

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ADSL Bridge/Router User's Manual
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The bimap rule: Performing two-way translations
Unlike the other NAT flavors, the bimap flavor performs address
translations in both the outgoing and incoming directions.
In the incoming direction, when the specified interface receives a
packet destined to your public IP address, this address is
translated to the private IP address of a computer on your LAN.
In the outgoing direction, the private source IP address in a data
packet is translated to the LAN’s public IP address.
Bimap rules can be used to provide external access to a LAN
device. They do not provide the same level of security as rdr rules,
because rdr rules also reroute incoming packets based on the port
ID. Bimap rules do not account for the port number, and therefore
allow external access regardless of the destination port type
specified in the incoming packet.
1. Display the NAT Rule – Add Page, choose a Rule ID, and
select BIMAP as the Rule Flavor.
2. Select the interface and, if desired, a protocol that this rule
applies to.
3. In the Local Address field, type the private IP address of
the computer to which you are granting external access.
4. In the Global Address field, type the address that you want
to serve as the publicly known address for the LAN
computer.
The pass rule: Allowing specific addresses to pass through
untranslated
You can create a pass rule to allow a range of IP addresses to
remain untranslated when another rule would otherwise do so.