Re: Telling users and machines apart

From: Date: Tue, 07 Jun 2005 13:00:25 +0000
Subject: Re: Telling users and machines apart
References: 1  Groups: php.general 
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Merlin wrote:
I am getting more and more emails through my webforms submited by bots. It looks like some sites liky yahoo are placing an image into their forms and the human has to enter a code visible on the image to submit the form. After some googling I found captcha, but I do not like the images. Do you know if there is a class available for PHP which does create the image and does parts of the handling?
You might find this helpful: http://phpsec.org/articles/2005/text-captcha.html It uses an image, and there are valid complaints against such. Of course, you could also argue that CAPTCHA has very little to do with security, and I'd have to agree. :-) Other approaches include asking a simple question that any user will know and throttling requests from the same client to restrain the scope of the problem. Hope that helps. Chris -- Chris Shiflett Brain Bulb, The PHP Consultancy http://brainbulb.com/

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