Which port should be forwarded for remote acceess from automation builder (over internet) to the AC500 plc ?

I have forwarded port 1200 for PLC LAN address (to some unused WAN port) because i saw (with TCPView) that this port is used when i was connected locally from automation builder to AC500 PLC but still i can't connect over internet (when i have used fixed dyndns IP address and WAN port in codesys communication parameters and also made firewall exception for this port).