So many specs, which one to choose?

I choose you, draft-ietf-behave-rfc3489bis-05!

The updated draft removes the attempt to discover the type and binding lifetime of the NAT device. This is a good thing as I noticed problems when testing other implementations of STUN clients where the results would be inconsistent or just incorrect, sometimes changing between STUN requests. I originally chalked the variations up to a flakey implementation but it seems the VSP (very-smart-people) working on the RFC noticed the same problem.

NAT

Network Address Translation

Nasty little critters. Get on my nerves.

NAT in Wikipedia

NStun

STUN, Simple Traversal Underneath Network Address Translators.

The N is for .NET. :-)

STUN in Wikipedia