Miredo is an implementation of the "Teredo: Tunneling IPv6 over UDP
through NATs" proposed Internet standard (RFC4380). It can serve
either as a Teredo client, a stand-alone Teredo relay, or a Teredo
server, please install the miredo-server or miredo-client aproprietly.
It is meant to provide IPv6 connectivity to hosts behind NAT
devices, most of which do not support IPv6, and not even
IPv6-over-IPv4 (including 6to4).
Project homepage: http://www.remlab.net/miredo/