In my experience people behind NAT very much like Skype, games, WebRTC, file sharing etc to work. They're usually not very knowledgeable about firewalls but mos

In my experience people behind NAT very much like Skype, games, WebRTC, file sharing etc to work. They're usually not very knowledgeable about firewalls but most often used host-based firewalls. Which is good since they're generally much more easier to configure according to your app needs.