U.S. Cellular® 4G LTE™ Router (LG2200D)
5.Select the Port Triggering radio button.
6.Clear the Disable Port Triggering check box.
If this check box is selected, the router does not use port triggering even if you have specified port triggering settings.
7.In the Port Triggering
This value controls how long the inbound ports stay open when the router detects no activity. This value is required because the router cannot detect when the application terminates.
Application Example: Port Triggering for Internet Relay Chat
Some application servers, such as FTP and IRC servers, send replies to multiple port numbers. Using port triggering, you can tell the router to open more incoming ports when a particular outgoing port starts a session.
An example is Internet Relay Chat (IRC). Your computer connects to an IRC server at destination port 6667. The IRC server not only responds to your originating source port, but also sends an “identify” message to your computer on port 113. Using port triggering, you can tell the router, “When you initiate a session with destination port 6667, you must also allow incoming traffic on port 113 to reach the originating computer.” The following sequence shows the effects of the port triggering rule you have defined:
1.You open an IRC client program to start a chat session on your computer.
2.Your IRC client composes a request message to an IRC server using a destination port number of 6667, the standard port number for an IRC server process. Your computer then sends this request message to your router.
3.Your router creates an entry in its internal session table describing this communication session between your computer and the IRC server. Your router stores the original information, performs Network Address Translation (NAT) on the source address and port, and sends this request message through the Internet to the IRC server.
4.Noting your port triggering rule and observing the destination port number of 6667, your router creates another session entry to send any incoming port 113 traffic to your computer.
Control Access to the Internet
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