I guess you are in the wrong forum. This forum is JME related. Furthermore without seeing code nor exception nor anything beside a very hard to understand english nobody will be able to point you in any direction.
But maybe a sample like sim-eth or sim-eth-es may help to get started with network based game?
and the links you send gives me the impression that you should ask in some android forums?
If I understand his post correctly, he’s trying to figure out how to correctly do UDP networking in the presence of a NAT. It’s not exactly jME specific, but it’s relevant for peer-to-peer multiplayer game authors. It’s not an inherently stupid question.
As far as I know, the router works according to the rules set by using the administrative special interface. It also lists the available ports. And it would be strange if these rules were changed automatically at the request of PC users.