This method is based on the OpenVPN project (http://openvpn.sourceforge.net/).

OpenVPN is basically a Layer 3 tunnel over UDP/IPv4 or TCP/IPv4, so it is used to set up a router that uses the tunnel interface to route IPv6. It is capable of traversing NATs and can, if needed, use strong encryption over SSL.

This method is a solution for those calling for a more robust way to offer IPv6 connectivity in a NAT environment.