[Mimedefang] Streams and MaxRecipientsPerMessage

[David F. Skoll]

WBrown at e1b.org wrote:

> Once the MTA authors adopt any new standard, the spammers will.

Only if they're force to.  As long as an MTA accepts multiple
RCPT commands, where's the incentive for spammers to change?

> Look at SPF.

I'm looking... I don't see any reduction in spam due to SPF.  In fact,
it hasn't even made a serious dent in joe-jobs yet...

> Their income *REQUIRES* adaptability to stay ahead (or
> at least) even in the cat and maouse game of filtering.  Besides, if
> a new standard breaks some piece of ratware, how many tears will any
> of us shed?

The problem is the installed base.  If we break existing SMTP standards,
every single MTA in the world will need updating.  That's unlikely
to happen soon, if ever.

> But if we're generating bounces on messages that I reject, how do I
> know that I'm not bouncing them to someone that got joejobbed?

You don't.  There's really no nice way to handle this.  Your choices are
either silently discard the message (bad) or generate a bounce (bad).
Pick your evil. :-)

> I'd rather not be doing 
> that...  If SPF records were universally available with "-all", then we 
> could prevent this by enforcing them immediately at the MAIL FROM stage, 
> before even streaming by recipient.

Yes, that would certainly be good.  However, I expect that SPF will be
universally adopted around the same time that IPv6 is, which might happen
when there are no longer any Windows viruses. :-)

Regards,

David.