D-Link DSL-500, User Manual

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DSL-500 ADSL Router User’s Guide
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NAT Configuration
Network Address Translation (NAT) is a routing protocol that allows your network to become a private network
that is isolated from, yet connected to the Internet. It does this by changing the IP address of packets from a
global IP address usable on the Internet to a local IP address usable on your private network (but not on the
Internet) and vice-versa. The Router allows up to 128 host IP addresses.
NAT has two major benefits. First, NAT allows many users to access the Internet using a single global IP
address. This can greatly reduce the costs associated with Internet access and also helps alleviate the current
shortage of Internet IP addresses. Secondly, the NAT process creates an added degree of security by hiding your
private network behind one IP address. The NAT function will normally only allow incoming packets that are
generated in response to a request from a host within the LAN.
If your network uses web servers, FTP servers or other proxies used for data requests from outside the private
network, you can use NAT in conjunction with Port Redirection to allow appropriate use of your servers by
outside users. See the section on Port Redirection for more information.
For the purposes of network administration, NAT is almost indispensable. Hosts and servers on the internal
network can be moved easily. Using NAT together with DHCP can greatly reduce the workload of a network
manager while allowing tremendous flexibility.
To view the NAT Configuration menu, click on the NAT Configuration button:
NAT Configuration Menu
The following parameters can be configured using the NAT Configuration menu:
NAT Function Default = enabled. Select enabled or disabled to enable or disable the NAT
function.
DMZ State Default = disabled. Select enabled or disabled to enable or disable the DMZ
function.
DMZ IP Address With the DMZ State enabled, type in the LAN IP address of a designated
DMZ device. (see explanation below)