TG862G/CT & TG862R: 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 - TG862: 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://10.0.0.1 into the address box, and press the Enter key.  The Login page appears.
   
   NOTE: By default the LAN IP address is 10.0.0.1.  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 Gateway > At a Glance page appears.
   
    
    
3. On the left-hand menu, click on Advanced.  A sub-menu appears.
4. On the sub-menu, click on Port Triggering.  The Advanced > Port Triggering page appears.
5. On the Advanced > Port Triggering page:
   a.   Click the Enabled button.
   b.   Click the ADD PORT TRIGGER button.  The Advanced > Port Triggering Add page appears.  
   
   
    
6. On the Advanced > Port Triggering Add page:
   a.   Service Name - Enter a desired name for this profile.
   b.   Service Type - Click the drop-down tab and select TCP & UDP. 
   c.   Trigger Port From
          If one port is to be used, enter the port number.
          If a range of ports are to be used, enter the first number of the range.
   d.   Trigger Port To
          If one port is to be used, enter the port number.
          If a range of ports are to be used, enter the last number of the range. 
   e.   Target Port From
          If one port is to be used, enter the port number.
          If a range of ports are to be used, enter the first number of the range
   f.    Target Port To
          If one port is to be used, enter the port number.
          If a range of ports are to be used, enter the last number of the range.
   
   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.
   
   g.   Click the Add button.
   
     
    
7. Verify that the Advanced > Port Triggering page will display a Trigger entry.