An Explanation of Xbox 360 NAT Types

I finally broke down and purchased an Xbox 360 with Halo 3 . It is an incredible improvement over the first system and is backwards compatible. The first intriguing thing about the system from a technologist perspective is their idea of network address translation (NAT) types: Open, Moderate, and Closed. I didn't realise this was possible but after a few packet captures I learned a couple of things:

• Xbox Live uses port 3047
• Xbox Live uses UDP
• Xbox Live thinks Open NAT means UDP port 3047 is directly accessible on the Xbox in question behind your NAT device

This leads me to the conclusion that the Xbox Live and Vista ready devices are just engineered to provide holes in networks (utilizing Universal Plug 'n' Play (UPnP) of course). I guess acceptance of this as a requirement to play is something a security policy can help decide.