At 08:44 PM 8/25/2004 -0700, Rand Wacker wrote:
My concern for Sender ID is that since SPF has already claimed the FQDN
TXT dataspace for itself (and since SPF is seeing parallel adoption
regardless of where Sender ID goes), trying to stuff a second Sender ID
record in the same data space will be problematic for some, and if we
ever try to evolve this to a third version then it will *never* fit.
I share this concern, but...
The solution I would suggest is to put spfv2/pra records in a sub-domain
such as _marid.company.com. While it would be nice to recommend that
people begin allowing TCP DNS queries, it is unlikely that the highest
volume sites would ever want to implement such.
I think it was brought up earlier that using a prefix like _marid would break
the use of wildcards (can't do _marid.*.example.com). But it wasn't clear (to
me, at least) whether wildcards would work in this application, even without
the prefix. Wildcard support would be very nice to have, to provide symmetry
with wildcard MX records for incoming mail. Can anyone clear up whether adding
the prefix breaks wildcards, or were they already broken?
Of course, a new record type would be preferable, but there are real-world
deployment issues there.
-Jim