What are the advantages of DKIM?
- by duff
After making my server sign outgoing email I started to wonder what the benefits are.
This is the opposite of a previously asked question.
Naively I see two benefits:
We can throw away all emails which don’t carry a
valid signature: Wrong! Mail
forwarders (like Mailman) will
produce emails from someone at
«domain which signs» which are not signed
correctly (in their forwarded
shape).
We can skip spam checking on signed
email: Wrong! A spammer can
send a single email through e.g.
gmail.com and then resend that email
as-is (w/o changing headers) to a
million people.
So what are the selling points of DKIM?
