On Thu, 11 Aug 2005, Daniel Taylor wrote:
But being able to have a TXT spf record that is adjusted to account
for foibles of early implementations (like rejecting on ?, or over
counting ptr mechanisms), while having a stricter/more concise
SPF/type99 record that a compliant implementation can take seriously
could be very useful.
The problem with this is that too many DNS servers "return" DNS Timeout
instead of NX_DOMAIN when queried for type99. This makes querying for type99
first problematic. With the two assumed to be identical, the heuristic
of querying TXT first, then treating TIMEOUT as NX_DOMAIN for SPF works
around the broken DNS server problem.
--
Stuart D. Gathman <stuart(_at_)bmsi(_dot_)com>
Business Management Systems Inc. Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flamis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.