> On 15 Aug 2017, at 20:28, Paul Vixie <p...@redbarn.org> wrote: > > we can specify that AAAA be sent as additional data for QTYPE=A, and that A > be sent as additional data when QTYPE=AAAA.
It's awkward. >From the stub point of view, how does it know that the server will return >additional address records? How does it tell the difference between no >support, no records, or an empty cache? To what extent do the additional >records actually help clients to avoid double queries? >From the recursive server point of view, should it delay answers so it can >fill in the additional section? What if a broken authority doesn't answer to >AAAA queries? DNSSEC can help a bit because there would be a visible proof of nonexistence to disambiguate some cases. > given identical deployment curves along both the ANYA and additional-data > timelines, we will get identical results. ANYA has the advantage of clear signalling that the server supports it or not, though broken servers or middleboxes might make the negative answer rather slow. But we would need some kind of modelling or experimental evidence to see if it increases the query load by 50% (the worst case) rather than reducing by 50% (the goal). Tony. -- f.anthony.n.finch <d...@dotat.at> http://dotat.at _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
