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Re: [TLS] TLS Client Puzzles

Martin Thomson <martin.thomson@gmail.com> Sat, 11 July 2015 02:33 UTC

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Date: Fri, 10 Jul 2015 19:33:25 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: noloader@gmail.com
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Subject: Re: [TLS] TLS Client Puzzles
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On 10 July 2015 at 18:06, Jeffrey Walton <noloader@gmail.com> wrote:
>> Computational puzzles can be reduced to that.  If a mobile device
>> can't solve a (small) bitcoin puzzle, it can contact a server that
>> can.
>
> Doesn't that sort of delegation open another attack surface?

Not if you consider that the mobile device is known to the server it
contacts at the time it makes the request.  The problem puzzles
address is one where the client identity is unknown until the server
commits the work.

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