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CONFIGURING NETWORK
ADDRESS TRANSLATION
This section provides an overview of Network Address Translation
(NAT) and instructions for modifying the default configuration
on your device.
Overview of NAT
Network Address Translation is a method for disguising the private
IP addresses you use on your LAN as the public IP address you use
on the Internet. You can define NAT rules that specify exactly how
and when to translate between public and private IP addresses.
Definition: A private IP address is created by a network
administrator for use only on a LAN, whereas
a public IP address is purchased from the Internet
Corporation for Assigned Names and Numbers
(ICANN) for use on the Internet. Typically, your
ISP provides a public IP address for your entire
LAN, and you define the private addresses
for computers on your LAN.
In a typical NAT setup, your ISP provides you with a single public
IP address to use for your entire network. Then, you assign each
computer on your LAN a unique private IP address. (Or, you define
a pool of private IP addresses for dynamic assignment to your
computers, as described in Configuring Dynamic Host Configuration
Protocol.) On the ADSL Barricade, you set up a NAT rule to specify
that whenever one of your computers communicates with
the Internet, (that is, it sends and receives IP data packets)
its private IP address - which is referenced in each packet -
will be replaced by the LAN's public IP address.