ubuntu - What Iptables rules need I to forward a windows remote desktop connection?

I have this situation:

network mask. 255.255.255.0

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  router/gateway: Ubuntu server (only command line, no gui) with internal lan ip 192.168.0.2 and a dynamic dns on the external ip

  
  


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  Windows pc on 192.168.0.1 with RDP (remote desktop connection) enabled on 3389

  
  

I want to forward the RDP service on the external address: how can i do that?

What are the iptables rules I need to connect to my Windows pc from the outside world?