I believe that the way to do it is on page 31 of this user guide.
http://www.speedtouch.com/pdf/510/st510_guide_en.pdf
You need to access your routers Web interface first, the factory default is the adress 10.0.0.138, but your isp may have changed that.
Well into the web interface click on NAT settings to get to the picture on page 31.
You will have to make three entries into the nat table.
inside ip: is your internal ip adress which can be found by opening a command promt and typing ipconfig.
outside ip can be found by going to the this website.
http://www.myip.dk
These things are the same with all entries. What needs changing with eachentry is the ports. The inside and outside ports should be the same on the entry.
first entry:
inside port you type 2300-2400 and select tcp in protocol
second entry : 2300-2400 and select utp
third entry : 47624 and select tcp
I hope this helps, otherwise just ask again.
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