Re: [saag] Liking Linkability

Sam Hartman <> Sun, 21 October 2012 17:55 UTC

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From: Sam Hartman <>
To: Kingsley Idehen <>
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Date: Sun, 21 Oct 2012 13:55:25 -0400
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Subject: Re: [saag] Liking Linkability
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I think if I hear the phrase  context fluidity or nebulous enttity one
more time I'm going to give up in disgust.
Those phrases don't have enough meaning to have any place in a security

You seem to believe that it is necessary to prove an event is related to
a person in order to have a privacy problem.
If  there  are 20 seditious (in the context of some government)
messages posted and  the government is able to link those events down to
3 machines and conclude that only 10 people had access to those machines
at the same time, you have a privacy problem.
If the government decides that executing 10 people  is an acceptable
cost those 10 people are just as dead even if 9  of them had nothing to
do with it.

Sitting there going "you never proved it was me, only my machine," isn't
going to help you as the fluids of your context are leaking out of an
ever more nebulous entity.
The fact is that by linking events, people can gain information about
real-world entities that might have had something to do with an event.
To the extent they gain that information, there is a loss of privacy.

Not all losses of privacy are bad.
Not all linkability is bad.
I give up privacy and create linkability every time I log into a site,
so that I can store preferences, manage entries I've posted in the past,
Of course for the most part I'm not risking my fluid context with what I
do online. I'd probably decide preferences weren't worth it if that was
the potential price.

But seriously, can we either move this discussion off IETF lists or use
enough precision and stop hiding behind vague terminology that we can
have a computer security discussion?

Thanks for your consideration,