G.shdsl Router User Manual
NAT/DMZ
NAT (Network Address Translation) is the translation of an Internet
Protocol address (IP address) used within one network to a different IP
address known within another network. One network is designated the
inside network and the other is the outside. Typically, a company maps its
local inside network addresses to one or more global outside IP addresses
and reverse the global IP addresses of incoming packets back into local IP
addresses. This ensure security since each outgoing or incoming request
must go through a translation process, that also offers the opportunity to
qualify or authenticate the request or match it to a previous request. NAT
also conserves on the number of global IP addresses that a company
needs and lets the company to use a single IP address of its
communication in the Internet world.
DMZ (demilitarized zone) is a computer host or small network inserted as
a “neutral zone” between a company private network and the outside
public network. It prevents outside users from getting direct access to a
server that has company private data.
In a typical DMZ configuration for an enterprise, a separate computer or host receives requests
from users within the private network to access via Web sites or other companies accessible on the
public network. The DMZ host then initiates sessions for these requests to the public network.
However, the DMZ host is not able to initiate a session back into the private network. It can only
forward packets that have already been requested.
Users of the public network outside the company can access only the DMZ host. The DMZ may
typically also have the company’s Web pages so these could serve the outside world. However, the
DMZ provides access to no other company data. In the event that an outside user penetrated the
DMZ host’s security, the Web pages might be corrupted, but no other company information would
be exposed.
Press NAT/DMZ to setup the parameters.
If you want to enable the NAT/DMZ
functions, click Enable. Enable the DMZ
host Function is used the IP address
assigned to the WAN for enabling DMZ
function for the virtual IP address.
Multi-DMZ: Some users who have two or
more global IP addresses assigned by
ISP can be used the multi DMZ. The table
is for the mapping of global IP address
and virtual IP address.
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