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Re: Plug and play alternatives to captcha

for

From: Jared Smith
Date: Apr 17, 2008 8:10AM

On Thu, Apr 17, 2008 at 7:38 AM, Moore, Michael
< <EMAIL REMOVED> > wrote:
>
> Captcha is raising its ugly head here again so I am searching for a plug
> and play alternative to the usual inaccessible distorted letters that
> are available in most modules. I have code examples of alternative ways
> of accomplishing this but my customers are looking for an off the shelf
> solution that they can just add to the form mail.

Here are a few options:

http://system-x.info/?pageid=18&;menutree=47

http://green-beast.com/blog/?p=128

http://www.purple-dogfish.co.uk/free-stuff/accessible-captcha

*All* CAPTCHAs can be broken. Even the most complex, inaccessible ones
at Yahoo and Google are being bypassed now. The question you have to
ask is, "would anyone dedicate a lot of time to implement a system for
bypassing my CAPTCHA?" If the answer is "no", then you don't even need
to implement CAPTCHA at all. If the problem is spam from a web form,
CAPTCHA *is not* the best solution.

By implementing just a couple of the simple, back-end techniques I
wrote about at http://www.webaim.org/blog/spam_free_accessible_forms/
you can get rid of probably 99.9% of bot submissions. While someone
could get around all of these techniques (and indeed any CAPTCHA,
particularly the "accessible" ones",) they probably are not likely to
spend the time to do so just to send you a bit of spam. For the many
sites on which I have implemented this approach, the spam has been
reduced to at most a few per year - and those are almost certainly
human spammers.

Jared Smith
WebAIM