Specify Internet Port Settings
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AC750 Wireless Dual Band Gigabit Router R6050
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 Timeout
field, enter a value up to 9999 minutes.
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.
