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Re: on the nature of trust

At 12:04 AM 2/13/98 -0500, you wrote:
>>On Thu, 12 Feb 1998, Tony Bartoletti wrote:
>>-> Ed,
>>-> I do believe that your definition of Trust (in the sense analogous to
>>-> Information Theory) is the most elegant and useful one, to repeat:
>>-> > Trust: "Trust is that which is essential to a communication channel
>>-> >         which cannot be transferred from a source to a destination
>>-> >         that channel"
>This definition would apply equally well to my modem.
>Also consider the following thought experiment. I establish an email
>correspondence with a person who I have never met before. Over the
>course of ten years my only means of communication with this person
>is through email. Is is possible to establish a property that corresponds
>to our term trust as a result?
>            Phill

This is a good point.  On the surface, it seems we have no (particularly)
trusted channel (nor trusted end-point) and yet over time, trust develops.
On closer examination, there are other "trusted" channels (likely) in use.
If this correspondent habitually maintained positions which you later found
to be incorrect or misleading (they assert they are in the black, but your
independent check on their credit shows they are in the red) you would not
gain much trust in them.

What is interesting is that, where information gained through independent
channels serve to corroborate the position of the correspondent, trust seems
thus to be gained not only in the correspondent, but "transferred" to the 
formerly untrusted channel.

One could, I suppose, construct a pathological situation, wherein you begin
correspondence with someone who, unknown to you, is an inveterate liar.  And
yet, every email you exchange is intercepted by a MITM who edits the liars
statements to turn them into truths.  Now, from the omniscient point of view,
you should neither trust the correspondent, nor the channel.  Yet you may
end up trusting both.


Tony Bartoletti                                             LL
SPI-NET GURU                                             LL LL
Computer Security Technology Center                   LL LL LL
Lawrence Livermore National Lab                       LL LL LL
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