[VOIPSEC] IPv6 and the demise (or not) of NAT (was Re: Interactive Connectivity Establishment (ICE))

[Dan Wing]

> >         Another big problem with UPnP is the double-nat problem.
> >Put a device behind two UPnP NATs and you can't open a port 
> >through both.
> >With STUN/etc, you can open ports through any number of NATs.
> 
> Except if one of those NAT's is symmetric (which is 90% of 
> all routers are) then it maybe broke.

draft-jennings-behave-test-results,
<http://www.ietf.org/internet-drafts/draft-jennings-behave-test-results-01.t
xt>, shows test results of a couple dozen NATs.  Only one NAT was found to
be symmetric.  

Do you have other data to share?

-d