Re: [ietf-dkim] A more fundamental SSP axiom

Michael Thomas <mike@mtcc.com> Fri, 04 August 2006 23:08 UTC

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Date: Fri, 04 Aug 2006 15:54:51 -0700
From: Michael Thomas <mike@mtcc.com>
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To: John L <johnl@iecc.com>
Subject: Re: [ietf-dkim] A more fundamental SSP axiom
References: <20060804173538.54245.qmail@simone.iecc.com> <44D3C0BB.9000405@mtcc.com> <20060804174955.N15734@simone.iecc.com> <44D3C8DB.4070101@mtcc.com> <20060804184321.L23892@simone.iecc.com>
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John L wrote:

>> I cannot see how SSP can do anything but make false positives more 
>> likely. The real question is whether the gain in eliminating harmful 
>> mail is worth the occassional false positive. So if what you are 
>> saying is true, law firms would be literally nuts to turn SSP "I sign 
>> everything" on, and so I'm surprised to hear that you think they should.
>
>
> At the moment, I agree with you.  Considering the value of the 
> messages, I'm surprised we don't see more fake mail saying that a case 
> has been dismissed or a hearing postponed.  If that happened, the 
> answer might be different.

Ah, that sounds a *lot* more like they want whitelists than SSP. In any 
case, if
that became prevalent you wouldn't want the defaultish disposition of "I 
sign
everything" to be reject. There would  be far too high a risk for a 
false positive
if what you're saying is true. The best you could hope for is to hope 
all of your
whitelisted domains get through mostly unscathed and then slavishly go 
through
the potentially spoofed ones, mostly likely with wetware. This is, of 
course, a
hard problem and DKIM is only likely to go so far as to help it.

       Mike
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