[SATLUG] Attn: Bob Tracy

[Bob Tracy]

David Kowis wrote:
> Unfortunately the way to win the war on spam is to prevent anyone from
> seeing the mail. Rejection based on envelopes is ideal, but you don't
> have a good enough method of ensuring that what is in that envelope is
> garbage.

Nod.  The more usual case is that I don't have a good enough method of
ensuring that what's in the envelope is NOT garbage :-).  On a more
serious note, most of the false positives (rejects) that I see are due
to the blacklists.  I suspect that I could cease using the blacklists
entirely without loss of filtering capability, which is an experiment
I'll try in the near future.

Other false positives occur due to DNS misconfigurations (willful or
otherwise), and failure to play by the rules.  The "rules" (such as they
are) have evolved over time, but the overall concept is that the sender's
address should somehow correlate with the host that's attempting to
deliver the mail on behalf of that sender.  In that regard, I try to be
as flexible as possible, but as an example of where automatic correlation
fails, there's no automatic way of knowing that a yahoo.com host is
authorized to send mail on behalf of a sbcglobal.net user in the absence
of DNS records to establish such a relationship.  As a human, I know that
SBC (whoops! AT&T) and Yahoo! are in bed with each other, and it's easy
enough to do the correlation manually on that basis.  Therefore, until
"sbcglobal.net" gets its act together and publishes the appropriate DNS
records, I have to explicitly whitelist each sbcglobal.net correspondent
whose mail is delivered via yahoo.com.  Fortunately, the number of
special cases due to this specific example is currently small :-).

> I should probably turn it (reject_unknown_client)
> off to avoid robbing my statistical filter of data.

:-)

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Bob Tracy                   WTO + WIPO = DMCA? http://www.anti-dmca.org
rct at frus.com
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