On Thu, 30 Sep 2004, Stephane Bortzmeyer wrote:
On Wed, Sep 29, 2004 at 01:18:49PM -0700,
william(at)elan.net <william(_at_)elan(_dot_)net> wrote
a message of 108 lines which said:
SPF2.0/PTR | Most can comply except situations with "uncooperative" ISP
Do note that this case is the norm in Africa. It is extremely uncommon
to have an ISP which has an in-addr.arpa delegation. (I do not say
they don't want to delegate to the client, I say they do not have it
in the first place.) Any PTR-checking scheme is a sure way to widen
the digital divide.
We don't really care if they don't have working IN-ADDR deligation, in
that case they would not have any PTR records and nothing to check on.
What is important is cases where IN-ADDR is in fact working but ISP is
not setting it to the proper name of smtp server that its client runs -
that is what I call "uncooperative" ISP. In reality the way to combat
this is with market economy - if they are not doing what their clients
need, the client will go to their competitors.
I also would note that AOL and several other ISPs already do require
working PTR records for any SMTP server sending email to them, such
policies obviously are advantageous for SPF/PTR.
--
William Leibzon
Elan Networks
william(_at_)elan(_dot_)net