It's only useful for keeping your own users in line.
Which is exactly what I said. Providers policing their users was not widely
done until around the time of DKIM. I'm dubious about any cause and effect,
providers started to clamp down around then after years of doing exactly
nothing.
Actually, the main reason SMTP AUTH is used to allow your users to send
mail from computers off your own network without making your mail server
an nuisance open relay. I agree that DKIM has nothing to do with this,
nor with tracking individual mail senders. On my system the identity of
the sending user is in a Received header, not the DKIM signature which I
think is typical.
Regards,
John Levine, johnl@xxxxxxxxx, Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly
