D-Link DSL-520B

43D-Link DSL-520B ADSL2+ Modem User Manual
Section 7 - Device Info
Port Triggering
Ifyoucongureporttriggeringforacertainapplication,youmustdetermineaso-calledtriggerportandtheprotocol(TCP
or UDP) that this port uses. You then assign the public ports that are to be opened for the application to this trigger port. You
can select known Internet services or manually assign ports or port blocks.