From my point of view, the question is does a new RR actually
bring something advantageous to the table.
Yeah, it makes wildcards work, which is fairly important in the
presumably common situation where you want to say that none of your
subdomains sends mail. If you're going to use a TXT record, you need
to use a _something component in the name to keep it from colliding
with _domainkey and other uses of TXT, which makes wildcards not work.
; this attempt to condemn mail from subdomains won't work
; because internal * in a name doesn't work
_ssp.*.example.com TXT "ssp=bogus"
; but this will work (give or take adding explicit SSP records to nodes
; that have other kinds of records) because terminal * does work
*.example.com SSP "bogus"
And is that advantage enough to overcome the energy barrier of the
deployment difficulties.
That seems to be more a political than a technical question at this point.
R's,
John
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