[Freeswitch-users] Dynamic WAN IP

I am doing my first steps with Freewswitch and i have a few questions regarding the config. I have a DSL connection at home with dynamic WAN IP and the router has the No-IP script to resolve a domain eg atux.ddns.net how can i configure it in the Freeswitch, please? Also how do i configure a STUN server, since i would like to register some remote extensions on Freeswitch, for testing. How do i configure a STUN server and if you have a decent STUN server to suggest, please.