TG862G/NA: Port Triggering Setup

When setting up a device for remote access, there may be situations in which Port Triggering needs to be set up in the TG862 instead of Port Forwarding. Port Forwarding allows the configured ports to always stay open. With Port Triggering, the ports are opened temporarily, and are only opened when triggered by specific behavior.

Port Triggering is a safer method for opening specific ports for special applications (e.g. video conferencing programs, interactive gaming, file transfer in chat programs, etc.) because they are dynamically triggered and not held open constantly or erroneously left open via the router administrator and exposed for potential hackers to discover.

When the TG862 detects outgoing data on a specific port number set in it's Trigger Range, the resulting ports set in it's Target Range are opened for incoming data. If no outgoing traffic is detected from the Trigger Range for 10 minutes, the ports listed in the Target Range will close.  Port Triggering is not enabled by default.  This document describes how to create a Port Triggering Entry.

NOTE 1: When setting up a host device like a web server, port forwarding should be used instead of port triggering. This way, the ports will stay open for users to connect. To setup port forwarding in the TG862, please refer to Answer # 8263 - TG862G/NA: Port Forwarding.

NOTE 2: Only one device should make outbound connections on a specific port. If two or more devices attempt to make outbound connections on the same port at a given time, there will be a conflict, and port triggering will not work correctly.

Creating a Port Triggering Entry

1. Launch a web browser, such as Internet Explorer, Firefox, or Safari.  Enter http://192.168.0.1 into the address box, and press the Enter key.  The Login page appears.
   
   NOTE: By default the LAN IP address is 192.168.0.1.  If the default address has been changed, enter the custom address in the address box.
    
2. On the Login page:
   a.   Enter admin in the Username field.
   b.   Enter password in the Password field.
   c.   Click the Login button.  The System Basic Setup page appears.
   
    
    
3. On the top-menu, click the Firewall tab.  The Firewall Settings page appears.
   
   
    
4. On the Firewall Settings page, click on Port Triggers from the left-hand menu.  The Port Triggers Configuration page appears.    
    
5. On the Port Triggers Configuration page, click the Add button.  The Add Port Trigger page appears.
   
   
    
6. On the Add Port Trigger window:
   a.   Description - Enter a desired name for this profile.
   b.   Outbound Port 
          If one port is to be used, enter the desired port number into both fields.
          If a range of ports are to be used, enter the first number of the range in the first field and the last number of the range into the second field.
   c.   Format - Click the drop-down tab and select Both.
   d.   Inbound Port  
          If one port is to be used, enter the desired port number into both fields.
          If a range of ports are to be used, enter the first number of the range in the first field and the last number of the range into the second field.
   
   NOTE: In the example below, if any device connected to the TG862 makes an outbound connection on port 2000, the TG862 will automatically forward ports 2001 - 2005 to that same device.
   
   e.   Click the Add Port Trigger button.
   
     
    
7. Verify that the Port Triggers Configuration page will display a trigger entry.