Just to expand on that, with IP6, it would make sense to simply give every router, DSL "modem" etc a [ed: theoretically, publicly] routable ipv6 subnet. This makes (in theory) everything easier: the firewall can simply block/allow -- no need for long chains of NAT-rules. It might make networks marginally more transparent -- but it really means very little in terms of security. Nor really for privacy.