In message <[email protected]> Mikael Abrahamsson writes: > On Wed, 1 Aug 2012, Curtis Villamizar wrote: > > > Same answer as one given on that thread. If a device can support > > IPv4, then use NAT4. If a device can only support IPv6, then the > > DNS64 belongs on the IPv6-only device. To that device all host return > > Am I interpreting you correctly in that you're saying that an IPv6 only > device should have a built in resolver that does DNS64 in case of v6 only > connectivity? > > I can see that this would work, but is that a generally accepted solution? > On Android, this would mean that dnsmasq would need to gain DNS64 > functionality (and also needs to be able to detect the NAT64 prefix > somehow). > > -- > Mikael Abrahamsson email: [email protected]
Re "and also needs to be able to detect the NAT64 prefix somehow": Asking DNS to resolve nat64prefix might be a solution. It might find nat64prefix.sitelocal or nat64prefix.<something-in-search-path>. If so, then as long as it is on an IPv6 capable subnet (moot point if it is an IPv6 only host on a IPv4 only subnet) and can reach the nat64prefix, then it can reach the IPv4 world. This would work for mobile devices even without site local nat64 support as long as it knew where to find a remote nat64 gateway. OTOH preventing abuse of a remotely accessible nat64 gateway advertised in DNS would be a challenge. I don't think adding DNS64 to dnsmasq would be all that difficult. It is mostly translating A records into AAAA records unless I am missing something that is hard to do. Putting the DNS64 on the host would allow a mix of v6-only hosts and IPv4 only hosts and DS hosts on a DS network. On a v6-only subnet, v6 and DS hosts could operate with access to v4 only if they did DNS64. The option to put DNS64 in a gateway also exists, but would be a negative on a DS subnet if it were to accommodate a lone v6 only host (for example, a cellphone on the WiFi in a home or a hotspot running mostly v4 at this time). The problem with putting DNS64 at a gateway is that it breaks all of the v4 only devices (which are still plentiful). Curtis _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
