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Re: [Asrg] 3. Proof-of-work analysis

Tony Finch <dot@dotat.at> Wed, 19 May 2004 19:58 UTC

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To: richard@highwayman.com
From: Tony Finch <dot@dotat.at>
Cc: asrg@ietf.org
Subject: Re: [Asrg] 3. Proof-of-work analysis
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References: <LV1hjGBSmTqAFAry@highwayman.com> <CB27C1AA-A8AB-11D8-B336-000393863768@chromatix.demon.co.uk> <mevaB4e60fqAFAu2@highwayman.com> <03A0F711-A929-11D8-B336-000393863768@chromatix.demon.co.uk> <03A0F711-A929-11D8-B336-000393863768@chromatix.demon.co.uk>
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Richard Clayton <richard@highwayman.com> wrote:
>
>Goodman & Rounthwaite have an interesting paper on using Captchas to
>limit webmail usage (one conclusion is that you need quite a number of
>them). It was presented at EC'04 yesterday, but the link on Joshua's
>home page is not currently working -- I expect he'll fix it when he gets
>home :(
>        http://research.microsoft.com/~joshuago/

Do they address the captcha-solving porn surfers attack?
	http://catless.ncl.ac.uk/Risks/23.17.html#subj4

Tony.
-- 
f.a.n.finch  <dot@dotat.at>  http://dotat.at/
FITZROY: VARIABLE 3 OR LESS IN SOUTH, OTHERWISE NORTHEASTERLY 3 OR 4,
OCCASIONALLY 5. FAIR. MODERATE WITH FOG PATCHES.

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