User Manual

Advanced Settings
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N450 WiFi Cable Modem Router Model N450/CG3000Dv2
• Name. A name for the service.
• Start Port. The start port for the service.
• End Port. The end port for the service.
• Protocol. The protocol for the ports:
- TCP. TCP only.
- UDP. UDP only.
- Both. Both TCP and UDP.
• Local IP Address. Complete the local IP address for the computer that is using the
service.
6. Perform one of these actions:
• Click the Add button. The Active Forwarding Rules table displays the list of forwarded
ports.
• To delete a service, select the radio button in the Active Forwarding Rules table for
the service that you want to delete, and click the Delete button.
• To reset the selection in the Service list and to clear all the fields in the Add Custom
Rules, click the Reset button.
Port Triggering
Port triggering is an advanced feature that you can use to allow gaming and other Internet
applications that the firewall would otherwise block. You must know the port numbers the
application uses. Port triggering operates as follows:
1. A computer makes an outgoing connection using a port number defined in the Port
Triggering table.
2. The modem router records this connection, opens the incoming port or ports associated with
this entry in the Port Triggering List, and associates them with the computer.
3. The remote system receives the computer’s request, and responds using a different port
number.
4. The modem router matches the response to the previous request, and forwards the
response to the computer. (Without port triggering, this response would be treated as a new
connection request rather than a response. As such, it would be handled in accordance with
the port forwarding rules.)
Note: Only one computer at a time can use port triggering. After a computer
finishes using a port triggering application, a short time-out period
passes before another computer can use the application.
 To configure port triggering:
1. Type http://192.168.0.1 in the address field of your web browser.