[vox-tech] spam greylisting (was: [vox] Posting to the lists)

[Rick Moen]

Quoting Peter Jay Salzman (p at dirac.org):

> I was also thinking of looking into SPF.  I know it's flawed, but I'd
> like to take a look to see if it might work for me anyhow.  Do you
> know if anyone is using it these day?

Pretty much all the major mail handlers are publishing SPF records,
professing various degress of authority.  As long as you can enumerate 
in the DNS which hosts are authorised to MX for your domain, publishing
records for it seems like a no-brainer good idea.  (Some domain owners
protest that, for various reasons generally having to do with poorly
specified mail forwarding, they cannot predict what hosts should at any
given time be regarded as valid MXes.  Sucks to be them.)

On the MTA end while receiving mail from elsewhere, there are
innumerable ways to check on and act on other people's published
information.  Set your own policy, as your prejudices dictate.