Port Forwarding - NETGEAR CG834WG User Manual

Wireless Cable Modem Gateway CG834WG User Manual

Port Forwarding

With port forwarding, you can make local computers or servers available to the Internet for
different services. For example, FTP uses TCP ports 20 and 21. Select Port Forwarding below the
Advanced Heading, and the following screen displays:
Figure 3-4
The selections on the Port Forwarding screen are:
• Active Forwarding Rules: This table displays a list of ports that are currently forwarded.
• Choose Predefined Service: Select a predefined service from the pull-down menu.
• Add Custom Rules: You can set up a custom service that is not in the list of predefined
services.
• To access the local computer from the Internet, you must use the WAN address of your
gateway, which can be found on the Basic Settings screen.
Because the gateway uses Network Address Translation (NAT), your network presents only one IP
address to the Internet, and outside users cannot directly address any of your local computers.
However, by defining an inbound rule you can make a local server (for example, a web server or
game server) visible and available to the Internet. The rule tells the gateway to direct inbound
traffic for a particular service to one local server based on the destination port number. This is also
known as Port Forwarding.
Note: Some residential broadband ISP accounts do not allow you to run any server
processes (such as a Web or FTP server) from your location. Your ISP may
periodically check for servers and may suspend your account if it discovers any
active services at your location. If you are unsure, refer to the Acceptable Use
Policy of your ISP.
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v1.0, October 2007