reporting known/unknown recipients

Matus UHLAR - fantomas
Thu Apr 15 13:28:13 UTC 2010

> > From: Matus UHLAR - fantomas <>
> > I would like to ask your opoinion on reporting received and apparently even
> > rejected mail to DCC. Do you find it OK to
> >
> > - report rejected mail, as if it was acepted for all recipients?
> >
> > - count the number of provided recipients, not only those accepted?
> >   (e.g. for 3 known and 7 unknown recipients report 10)

On 15.04.10 13:10, Vernon Schryver wrote:
> I think the count for each DCC checksum is the number of addressees or
> target mailboxes, and not the number successfully hit advertising
> targets.  So dccm (with recent versions of sendmail) and dccifd in proxy
> mode (e.g. as a postfix before-queue filter) count SMTP Rcpt_To commands
> regadless of their validity.


> > - double or multiple the number of non-existent recipients in addition to
> >   number of those existing?
> >   (e.g. for 3 known and 7 unknown recipients report 17, 24 or even more)
> If you think that an attempt to send mail to a particular mailbox
> is proof that the message is spam, why not report it with a count
> of "many"?

I don't think that and I would be careful about rejecting mail just because
it was sent to one or more non-existing addresses.

However according to my experience, the more invalid addresses is mail sent
to, the more likely it's spam. Therefore I'm searching for ways to use
spammers' behaviour against them.

> Some people run spam traps.  See

> Many SpamAssassin+DCC installations use DCC thresholds of "many."  The
> only spam they detect with DCC are copies of messages sent to spam traps
> or otherwise reported with counts of "many"

The thing about DCC is, that I've seen it reject some valid "chain" mails
(jokes etc) that aren't apparently quite correct and apparently not abusive
in any way. I don't want to reject purely on DCC threshold.

Matus UHLAR - fantomas, ;
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
My mind is like a steel trap - rusty and illegal in 37 states. 

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