John D. Hardin wrote:
On Thu, 29 Mar 2007, Marc Perkel wrote:
John D. Hardin wrote:
Can anyone recommend a non-abusive way to validate email addresses?
Yes - Sender Address Verification (SAV) works very well. It is not
abusive. Especially the way Exim implements it.
I am not necessarily speaking of the context of a MTA.
Example pulled out of thin air: if you had a corpus and you wanted to
check the addresses within it, what would be a "polite" way to do so?
Just open an SMTP connection and see what the far end says to "RCPT
TO:", but put a tight rate limit on it?
If someone was doing that to my server, I would consider it an attack,
and blacklist them.
There is no polite way to do it. It's not polite to take advantage of
someone else's resources without their permission. That's exactly what
SAV does.
SAV is the same thing as TDMA/Challege-Response, only the challenge is
to the machine instead of the human. Most of the same arguments apply.
