A while back (probably 2 or 3 years) there used to be an email service
called either msgto.com or mailto.com or something like that. It worked
by the following (rather clumsy, but quite effective) method.
It kept a list of people who I authenticated as legitimate mailers to me
in its address list.
Any mail from someone in that list was automatically authenticated
Any mail from someone not in that list was held in abeyance and an email
sent to the return address of that piece of mail. If the person at\the
other end confirmed that they did indeed send it, then the mail was
forwarded to me and placed in a quarantine box for my approval
(whitelist) or disapproval (blacklist).
I used the service for a while and it proved very effective indeed. Of
course there are several opportunities for abuse:
Return address spoofing - so the return/verification emails become spam
to someone else
Mail delays - if the original sender were unavailable and it was a first
time send, then the mail would sit in abeyance until the original sender
returned.
Does anyone else remember the company/approach? Is it worth resurrecting
some of that thinking?
Regards
Christopher Bird
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