Email Server and DNS

John Levine johnl at
Mon Nov 4 04:11:09 UTC 2013

>MX, PTR, and SPF are really all you need.

So far so good, noting that a host name that doesn't look generic is
better than one that does.

> I would recommend you go a
>step further and use DKIM, ADSP, and DMARC.

Using DKIM is a good idea.  Do *not* use ADSP.  It is a failed
experiment which will provide no benefit and considerable pain.
(Check the author list on RFC 5617 before arguing, please.)

If you believe that your domain is heavily forged (which if you are
not Paypal, Facebook, or a large bank or ISP, it almost certainly is
not), you can set up a DMARC record to collect some statistics about
what mail other people are getting that appears to be from you.  Do
not try to use DMARC to tell people to quarantine or reject your mail
until you are really sure you understand the statistics you're


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