--On Wednesday, 26 March, 2008 22:41 +1100 Mark Andrews <Mark_Andrews@xxxxxxx> wrote: >... >> It would be needed until IPv6 takes over. > > It will be needed even *after* IPv6 takes over. There will > be lots of queries for A records long after the majority > of hosts don't have A records. > > We need to remove the implict MX from A to prevent the A > record lookups occuring as things currently stand. Mark, Whether that proposal is a good one or a bad one, it can't be done in 2821bis because that is a document moving from Proposed to Draft Standard and the implicit MX feature is _very_ widely deployed and used. So, IMO, this discussion is not directly relevant to the (already closed) Last Call on 2821bis and should probably be move to the ietf-smtp mailing list. Second, no matter what is done with standardization, it will be many, many years before one could count on those A RR lookups not occurring -- too much software out that that is very rarely updated. The advantage of the "MX 0 ." approach over getting rid of the implicit MX from A is that, if there were consensus for it, it can be deployed in less than geological time. But, either way, it seems to me that the correct (and only feasible) actions start with an I-D that says something useful and is discussed on, at least, the ietf-smtp list. Just my opinion, of course. john _______________________________________________ IETF mailing list IETF@xxxxxxxx https://www.ietf.org/mailman/listinfo/ietf