OpenVPN is (as the name indicates) a VPN solution. Licensed under the GPL it creates cross platform (layer 2) point-to-point or Ethernet-bridge tunnels over which IPv6 can easily be transported. The software multiplexes IPv6 in IPv4 UDP packets using functionality provided by the OpenSSL library, which may optionally be encrypted. As a VPN solution one has of course to regard one end of the tunnel as the "server" end and one as the client but both ends use the same software. The tunnel end at the site that provides IPv6 connectivity acts as the server. For more information on how OpenVPN works, please refer to the project’s homepage at: http://openvpn.sourcefourge.net