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Re: Trust and Transitivity
There are two different pictures here:
> 1. Skywalker signs Alice's key with tag X, so Skywalker trusts Alice in
> matters of X,
>
> 2. Skywalker meets Bob and Bob decides that he trusts Skywalker in matters
> of X.
>
> The question is: "Can you say that Bob trusts Alice in matters of X, based
> on the two assertions before?"
>
> The answer is "No". Let's see why.
trusts (1) Luke trusts re X
Bob -----------------> Luke --------------> Alice
(2) his certs
For (1) the trust isn't transitive. But For (2) we get a transitive picture:
trusts re X
Bob ------------------------------------> Alice
> When I sign your key with the tag X, I am saying that I trust you to be
> (honest, knowledgeable, use-good-judgement) in matters of X. I may not
> trust Khaddafi in such matters, or think that I do not, but if YOU do and
> you are basing your actions on his behalf, than I am implicitly trusting
> Khaddafi. Had I known that you get your direction from Khaddafi, I might
> not have placed trust in you in the first place, but that is a another issue.
trust re X directions
I ------------> YOU <------------ Khaddafi
(*)
This is not transitive (note the arrow points to the left). As said above,
I just have misplaced my trust and YOU missused it because you act on behalf
of Khaddafi.
--
read you later - Holger Reif
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