[Mimedefang] MIMEDefang - "Bounce" when really a SMTP rejection.

- kd6lvw at yahoo.com
Fri Aug 20 18:56:01 EDT 2010

--- On Fri, 8/20/10, Les Mikesell <lesmikesell at gmail.com> wrote:
> On 8/20/2010 2:06 PM, David F. Skoll wrote:
> > Kevin A. McGrail wrote:
> >>   To me, it's not a mis-naming.  A bounced email is rejected.  I.e. a
> >> bouncer doesn't let you in the club.
> > 
> > Weeelll... to me, "bounce" connotes actually generating and sending
> > a non-delivery notification.  I agree with the poster that "reject" is
> > better, but it's such low priority ATM that I don't care too much to
> > change it. :)
> If you are talking about 'real' mail servers, a
> non-delivery notification is always generated, so the only
> difference is whether it is created on your server or the
> one trying to send to you.   But most of what
> we try to reject isn't real mail from real mail servers so
> in practice there is a big difference.

Bad practice.  A bounce accepts and sends an NDR (or other response).  A reject is an SMTP rejection.  BIG DIFFERENCE.  With the former, one has accepted responsibility for the message, while with the latter, one has not.

A properly behaving mail server REJECTS that which it finds unacceptable during the SMTP transaction.  Such has been the BCP standard for at least the past 10 years, and was heightened during 2003 when spammers started forging the sender field.  As far as "the other server" (i.e. the sender) is concerned, why should "my server" care?  It might not even be a server - but spamware, in which case a rejection causes NOTHING, while an accept and bounce may cause backscatter.

It is a misnaming because they are separate and distinct actions.

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