Funny you should mention that... Andy works for the part of VeriSign that
does just that...
OK they are delegation records not A records but same difference.
[mailto:owner-ietf-mailsig(_at_)mail(_dot_)imc(_dot_)org] On Behalf Of Miles
Sent: Saturday, March 05, 2005 3:43 PM
To: Andrew Newton
Cc: MASS WG
Subject: Re: In response to Housley-mass-sec-review
--- Andrew Newton <andy(_at_)hxr(_dot_)us> wrote:
Let's say Yahoo has 40 million email accounts (that's
or low. Neilson Netratings indicates there are about 60M
unique Ymail users in the US alone (and they only measure web
mail users, not POP users -- and I'd guess their methodology
doesn't include the spammers). However, there are very few
providers at an order of magnitude more than your estimate --
there are a few more in the same.
I don't think it changes your point (just the example org),
however, I'd be surprised if there are organizations that add
or subtract 100s of thousands or millions of A records on a
more than daily basis.