WebAIM - Web Accessibility In Mind

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Re: A very interesting and comprihensive article on CAPTCHAs


From: Jared Smith
Date: Nov 18, 2011 8:21AM

On Fri, Nov 18, 2011 at 6:46 AM, Birkir R. Gunnarsson
< <EMAIL REMOVED> > wrote:

> I just received this link via the Blind Programming list

WebAIM has a similar, though a bit more detailed article from 2007
that outlines several CAPTCHA alternatives -

> The honey pot mentioned, that filters out spammers by having an
> additional hidden field, whose input indicates bot activity, since
> bots interact with the raw html bugs me, after all screen readers do
> that too.

We implement the hidden field after the submit button, hide it with
CSS display:none (a screen reader would not read it), and give it a
descriptive label that clearly indicates that the user should not
place anything within the field.

Our experience has been that this technique, along with a basic
naughty word list and form submission time detection (if they submit
the form in less than 3 seconds or more than 30 minutes) has
effectively blocked around 99% of bot and spam submissions.