Asus TM-AC1900 User Manual page 62

Trigger Port: Specify a trigger port to open the incoming port.
Protocol: Select the protocol, TCP, or UDP.
Incoming Port: Specify an incoming port to receive inbound
data from the Internet.
Protocol: Select the protocol, TCP, or UDP.
NOTES:
connection using the trigger port range 66660-7000. The IRC server
responds by verifying the username and creating a new connection
to the client PC using an incoming port.
it is unable to determine which PC is requesting for IRC access.
When Port Trigger is enabled, the router assigns an incoming port to
receive the inbound data. This incoming port closes once a specific
time period has elapsed because the router is unsure when the
application has been terminated.
particular service and a specific incoming port at the same time.
one PC at the same time. The router will only forward the port back
to the last computer to send the router a request/trigger.
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