I posted this info over on the IETF MARID mailing list, but I figured
folks here might be interested in it also.
Before the IETF meeting, I used a spammer's list of email addresses to
get a list of 1.3 million domain names. (I would like to thank both
the stupidity of a spammer for leaving his website open, and for IIS
for not recognizing index.html for this information.)
During my search, I found *no* TXT records that were even close to
conflicting with the "v=spf1" magic number.
Considering that 50% of all SPF records are under 35 bytes, and 99.8%
are under 200 bytes, I really don't think that the size of SPF records
is an issue.
Anyway, I thought you guys might be interested in them.
1289260 total domain names
33016 total TXT records found (some domains have more than one)
6320 have SPF records -> 19.1% of all domain level TXT records are
spf records
26359 domains have txt records
6315 domains have spf records
1456 domains found that were also in the adopt roll -> 23.0%
14192 spf_domains adoption roll
61554 estimated domains have SPF records. (This probably misses
most parked domains, of which I have heard rumors that there
are a least a couple hundred thousand with SPF records.
About a week alter, I ran some more checks over these same 1.3 million
domain names looking for Caller-ID records, and here is what I found:
1289260 total domain names
82 have Caller-ID records
57 have both Caller-ID records and SPF records
45 have "testing=true" in the C-ID records.
25 have C-ID records only, of which three (10%) are microsoft.com,
exchange.microsoft.com and hotmail.com
So, there are hundreds of times as many people who have published SPF
records without publishing Caller-ID records as vice versa. Caller-ID
has had about the same number of published records 3 months after
being announced as SPF had 3 weeks after it was announced, despite
MicroSoft getting a much more press coverage about its announcement.
I'm not sure what to make of this. It could be the difference between
XML vs the "simple" SPF syntax. It could be the availability of SPF
wizards. It could be availability of working code.
Whatever the cause, it would be best for the IETF to try and make sure
the MARID proposal follows the SPF trajectory.
-wayne