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Re: accessibility of CAPTCHA

From: Donald F. Evans <donaldfevans@aol.com>
Date: Mon, 11 Sep 2006 15:39:25 -0400
Message-ID: <4505BB6D.80709@aol.com>
To: WAI WCAG List <w3c-wai-gl@w3.org>

I think you're on the right track.  That is, there is no good solution.  
We have a lot of experience at both graphic and audio captcha, and 
neither work very well at keeping out the spammers and spimmers.

gv@trace.wisc.edu wrote:
> Interesting. 
>
> I think there is a lot of research being done on this type of approach.  I
> remember Tim Berners-Lee talking about it in 2000 I think it was.  
>
> I really think that - in the end - an approach like this will need to be
> used.  As you point out - computers will be better at CAPTCHAs than most
> humans - and trust is what you really want.   (When this is set up I want to
> employ it first on my email !!! Only trusted people get through!  (oops -
> where does that leave   relatives, 'the man',  people over 30, and the
> government.  Guess I will have a much leaner mailbox. ) 
>
> With all the problem with SPAM I would guess that this is quite difficult or
> someone would have done it already.   
>  
> For our guidelines then - we don't have anything better than what we have?
> {if you use CAPTCHAs then use more than one type}.   It doesn't sound good
> enough but no one seems to be able to come up with anything better.    PF
> took it on too and came to the same conclusion.   That there is no good
> answer. 
>
> Anyone else got an idea? 
>
> Thanks Gez. 
>
> Gregg
>
>  -- ------------------------------ 
> Gregg C Vanderheiden Ph.D. 
> Professor - Ind. Engr. & BioMed Engr.
> Director - Trace R & D Center 
> University of Wisconsin-Madison 
> The Player for my DSS sound file is at http://tinyurl.com/dho6b 
>  
>
>   
>> -----Original Message-----
>> From: w3c-wai-gl-request@w3.org 
>> [mailto:w3c-wai-gl-request@w3.org] On Behalf Of Gez Lemon
>> Sent: Sunday, September 10, 2006 4:23 PM
>> To: w3c-wai-gl@w3.org
>> Subject: accessibility of CAPTCHA
>>
>>
>> Hello everyone,
>>
>> In the 31st August 2006 teleconference, I had an action item 
>> to explore CAPTCHAs to see if we could come up with a 
>> sufficient technique for people with multiple disabilities [1].
>>
>> I explored several techniques, but was unable to come up with 
>> anything that could distinguish the intention of the user by 
>> ability alone.
>> Instead, I came to the conclusion that there could never be a 
>> truly accessible technique using a CAPTCHA. Although I 
>> couldn't think of a method using a CAPTCHA, I do think it 
>> would be possible to solve the problem using a social 
>> networking web service. It's quite an involved technique, so 
>> I've written it up online to make it a bit easier to read [2].
>>
>> [1] http://www.w3.org/WAI/GL/2006/08/31-wai-wcag-minutes.html#item08
>> [2] http://juicystudio.com/article/accessibility-of-captcha.php
>>
>> Regards,
>>
>> Gez
>>
>> --
>> _____________________________
>> Supplement your vitamins
>> http://juicystudio.com
>>
>>
>>     
>
>
>   

-- 
*Donald F. Evans*
Sr. Program Manager
Office of Accessibility
AOL LLC.
Phone: (703) 265-5952
Email: donaldfevans@aol.com
AIM: donaldfevans
Received on Monday, 11 September 2006 19:39:54 GMT

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