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However, you may want to expose your network to the Internet
in limited and controlled ways in order to enable some
applications to work from the LAN (for example, game, voice,
and chat applications) and to enable Internet access to servers
in the home network. The port forwarding feature supports both
functionalities. This topic is also referred as Local Servers.
The port forwarding page is used to define applications that
require special handling by DSL router. All you need to do is to
select the application protocol and the local IP address of the
computer that is using or providing the service. If required, you
may add new protocols in addition to the most common ones
provided by DSL router.
For example, if you wanted to use a file transfer protocol (FTP)
application on one of your PCs, you would simply select FTP
from the list and enter the local IP address or host name of the
designated computer. All FTP-related data arriving at DSL
router from the Internet henceforth is forwarded to the specific
computer.
Similarly, you can grant Internet users access to servers inside
your home network, by identifying each service and the PC that
provide it. This is useful, for example, if you want to host a Web
server inside your home network.
When an Internet user points his/her browser to DSL router
external IP address, the gateway forwards the incoming HTTP
request to your Web server. With one external IP address (DSL
router main IP address), different applications can be assigned
to your LAN computers, however each type of application is
limited to use one computer.
For example, you can define that FTP uses address X to reach
computer A and Telnet also uses address X to reach computer
A. But attempting to define FTP to use address X to reach both
computer A and B fails. DSL router, therefore, provides the
ability to add additional public IP addresses to port forwarding
rules, which you must obtain from your ISP, and enter into the
