Jason Bertoch jason at
Fri Dec 18 10:12:26 CST 2009

Ted Hardie wrote:
> Silly question: how well would using match the
> need identified in draft-jabley-sink-arpa ?
> It seems like it would be equally well guaranteed to be non-existant
> (short of change in the def of IPv4 and  Like
>, it would get you a valid SOA and nothing else.
> Am I missing something, or is this operationally equivalent?
> regards,
> Ted

Isn't the fundamental problem that SMTP can fall back to an implicit MX? 
  None of these solutions will stop spammers from skipping MX records 
and using direct-to-host connections.  Shouldn't we just consider 
dropping the implicit MX back door as opposed to getting creative with 
MX records that spammers will surely note and avoid anyway?

More information about the NANOG mailing list