I recently attended (and videotaped) an IPv6 conference here in New York, there was an interesting discussion about NAT in general, see http://www.youtube.com/watch?v=GpzEjFM2J0g

In the exhibitors space there was a very interesting Canadian firm called gogo6 - http://gogo6.com

They had some very interesting gadgets for implementing v6 tunnels across WANs, and even offer a free service  http://gogonet.gogo6.com/page/freenet6-tunnelbroker

Regards

j
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Joly MacFie  218 565 9365 Skype:punkcast
 VP (Admin) - ISOC-NY - http://isoc-ny.org
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