User's Manual

Configuring the Gateway
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SMCD3GNV Wireless Cable Modem Gateway User Manual
Using Advanced Features
Using the Advanced Features menu, you can:
 Enable or disable port forwarding. See page 84.
 Enable or disable port triggering. See page 87.
 Enable or disable port blocking. See page 91.
 Use the Gateway’s UPnP feature to auto-discover devices. See page 92.
Enabling or Disabling Port Forwarding
Using the Firewall menu (described on page 53), you can configure the Gateway to create a
firewall between your internal network and the Internet. A firewall keeps unwanted traffic
from the Internet away from your networked computers. There may be times, however, when
you want a “tunnel” to be created through your firewall, so computers on the Internet can
communicate to one of the computers on your LAN using a single port. This is handy for
running Web servers, game servers, FTP servers, or even video conferencing.
Port forwarding allows outside users access to the computers on your LAN using a given
port or range of ports. Using port forwarding, for example, one of your computers could run a
Web server (port 80) while another computer could run an FTP server (port 23) - both using
the same IP address.
You configure the Gateway’s port forwarding feature using the Port Forwarding menu. To
display this menu, click Advanced in the menu bar, and then click the Port Forwarding
submenu in the menu bar. Figure 46 shows an example of the menu.