UPnP/NAT Punchthrough

I have recently been working with UNET, and started work on a project using it. The game is a P2P, with one client as the server, or a host. The problem is that to get this to work, the host needs to port forward, which would deminish the players able to play by a lot.

I then went to forward my port for testing, then noticed Skype has ports forwarded automatically, and stumbled upon the feature of UPnP, and researched, and figured out it's pretty much what I need. Problem is, there's no...

UPnP/NAT Punchthrough