In <012f01c4650f$b26fe950$c803a8c0(_at_)tag> "Andrew G. Tereschenko"
<spf-discuss(_at_)spam(_dot_)24(_dot_)odessa(_dot_)ua> writes:
[...]
We have considered this idea in the past, and chosen not to
proceed for a number of reasons. The strongest reasons are:
if we did this we would use an underscore ---
"_spf.domain.com" and enough people believe that underscores
are not permitted in DNS to cause significant friction.
What the point ?
You do not wish to have congentions by using underscores,
but instead of this put data in default record - thich will definitely have
congentions.
The problem with the underscore is that there are many DNS hosting
companies that don't allow it, even though it is valid. Well, it is
valid in domain names, but not host names, which are slightly
different things.
There is no real congestion with the SPF records at the domain level
with other TXT records. I've done a couple of surveys recently (check
the archive for something with "stats" around May 20-25 and Jun
20-25). There was also a survey done last fall.
So far, you have ask a lot of very good questions. Unfortunately, all
of the questions you have raised have already been checked into and
discussed to death. SPF has been reviewed by a couple of the hard
core DNS gurus that write the DNS RFCs. While they aren't happy about
everything in SPF, they understand the need for speed and they can't
find any critical problems.
-wayne