Re: [saag] can an on-path attacker drop traffic?

Dan Harkins <dharkins@lounge.org> Sun, 04 October 2020 17:15 UTC

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Date: Sun, 04 Oct 2020 10:15:37 -0700
From: Dan Harkins <dharkins@lounge.org>
In-reply-to: <1601786570544.65950@cs.auckland.ac.nz>
To: Peter Gutmann <pgut001@cs.auckland.ac.nz>
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Subject: Re: [saag] can an on-path attacker drop traffic?
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On 10/3/20 9:42 PM, Peter Gutmann wrote:
> Dan Harkins <dharkins@lounge.org> writes:
>
>> Which is fine but what use do you see in a protocol that is secure against
>> this "limited attacker" but not against the more powerful attacker?
> Because it's far easier to deploy a relatively straightforward, realistic
> protocol secure against a general attack than it is to deply an awkward,
> complex, impractical protocol that's theoretically (but often not practically)
> secure against a more unlimited attacker.  To quote the end of John Gordon's
> joke:
>
>    Now most people in Alice's position would give up. Not Alice. She has
>    courage which can only be described as awesome. Against all odds, over a
>    noisy telephone line, tapped by the tax authorities and the secret police,
>    Alice will happily attempt, with someone she doesn't trust, whom she cannot
>    hear clearly, and who is probably someone else, to fiddle her tax returns
>    and to organize a coup d'etat, while at the same time minimizing the cost of
>    the phone call.
>
>    A coding theorist is someone who doesn't think Alice is crazy.
>
> I don't need a theoretically perfect protocol that's practically un-
> deployable, I just need something that's practical and good enough for the
> job.

   For some people the job includes tax avoidance and fomenting of coups.

   Dan.