It appears that Murray S. Kucherawy <superu...@gmail.com> said: >-=-=-=-=-=- > >I'm wondering something about tree walks, which John Levine asked about in >November, as it's a topic of interest to the evolution of DMARC. > >I've read RFC 8020 which says an NXDOMAIN cached for "foo.example" also >covers later queries for "bar.foo.example". Makes sense. > >Can this be used (or maybe amended) to cover the queries if they come in >the reverse order?
In this application, no, because it's not doing a strict tree walk: _dmarc.newjersey.sales.bigcorp.wtf _dmarc.sales.bigcorp.wtf _dmarc.bigcorp.wtf The _dmarc tag means that none of the names is an ancestor of any of the others. It could also look at, e.g., sales.bigcorp.wtf and see if it has an NXDOMAIN and prune names below that, but I don't think that approach is likely to win overall. In a somewhat different world where we used RRTYPEs rather than _tag names, we could do tree walks a lot more efficiently. R's, John _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
