What's wrong with Victor's approach to spam

John Gilmore gnu at toad.com
Thu Jan 1 22:09:22 EST 2004

Victor.Duchovni at morganstanley.com wrote:
> Of the ~750000 messages inbound message recipients a day on the gateways I
> manage, 40% are rejected by RBL lists and private blacklists/content
> checks. 5% of the remainder is caught as spam by a commercial anti-spam
> content filter. The filter's detection rate against this RBL pre-screened
> sample is ~90%, the false positive rate is less than 0.01%. So we get rid
> of ~99.5% of spam with no hash-cash. This is good enough. I am not about
> to implement any CPU burning stamp generators any time soon.

Somehow, my personal emails are always part of that "false positive
rate" among self-satisfied anti-spammers like Victor.

Luckily I resisted the barrage of unsolicited phone calls from Morgan
Stanley, seeking to get my investment business.  So I don't have to
worry about Victor censoring the email from me to my broker.  But I'm
curious:  do the 'false positives' that result in a loss to a Morgan
Stanley customer get made whole out of Victor's paycheck?


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To: Victor.Duchovni at morganstanley.com, gnu at toad.com
Subject: Re: why "penny black" etc. are not very useful 
In-reply-to: <Pine.LNX.4.58.200312311428390.8740 at piias302.ms.com> 
Date: Wed, 31 Dec 2003 14:51:55 -0800
From: John Gilmore <gnu at toad.com>

Just checking whether your super effective "spam filters" allow me to
respond to the message that you sent to cryptography at metzdowd.com.

	John Gilmore


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