Siemens Gigaset Owner's Manual page 34

Configuring the Gigaset Router
Enabling Special Applications
Some applications, such as Internet gaming, videoconferencing, Internet telephony and
others, require multiple connections. These applications cannot work with Network
Address Translation (NAT) enabled. If you need to run applications that require multiple
connections, use the following screen to specify the additional public ports to be
opened for each application.
Specify the port normally associated with an application in the Trigger Port field, select
the protocol type as TCP or UDP, then enter the public ports associated with the trigger
port to open them for inbound traffic.
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