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How to avoid CAPTCHA ?
Posted: Thu Oct 02, 2008 5:20 pm
by Mds
Hi.
Is it possible to avoid CAPTCHA in our websites?
Thank you
Re: How to avoid CAPTCHA ?
Posted: Thu Oct 02, 2008 7:53 pm
by califdon
Mds wrote:Hi.
Is it possible to avoid CAPTCHA in our websites?
Thank you
Would you explain what you mean? What is it that you want to avoid?
Re: How to avoid CAPTCHA ?
Posted: Thu Oct 02, 2008 10:01 pm
by Mds
Thank you.
Well, almost always we should use CAPTCHA images in our form to avoid robots registering.
Like this :
http://recaptcha.net/
I wanna to know, is it possible to avoid it.
Means , is there a way to avoid using CAPTCHAs and prevent robots registering.
Do you understand what I mean ?

Re: How to avoid CAPTCHA ?
Posted: Thu Oct 02, 2008 10:18 pm
by Stryks
Sorry ... are you asking how to get around a captcha on someone else's site, or are you asking for alternatives to using a captcha on your site to prevent robot registrations?
Re: How to avoid CAPTCHA ?
Posted: Thu Oct 02, 2008 10:33 pm
by Mds
Sorry ... are you asking how to get around a captcha on someone else's site

Nope.
It was a simple question.
I wanna create a Form without any CAPTCHA images, and I wanna prevent robot registrations with a way except CAPTCHA

Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 1:01 am
by The_Anomaly
Mds wrote:Sorry ... are you asking how to get around a captcha on someone else's site

Nope.
It was a simple question.
I wanna create a Form without any CAPTCHA images, and I wanna prevent robot registrations with a way except CAPTCHA

You want to know if there are alternatives to CAPTCHAs for beating robots.
The only other thing I know of/seen are basically the same concept. For example, there will be a textbox with some random arithmetic, "2x2=" and the users answers it. I can imagine how this could be circumvented, but it is pretty cool.
The other thing I've seen are audio CAPTCHAs...but I doubt you'd want that. It's the same thing as a normal CAPTCHA, but the user is listening to the phrase instead of copying it from an image.
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 3:38 am
by mikelbring
What you do is create a text field called url and then hide it with css. Not a hidden field but one hidden with css. If that field has any info in it you simply exit(). The only problem is people without css browsers will 'could' be hurt. I do this on my site and it seems to work like a champ. Might add captcha later on tho.
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 3:47 am
by The_Anomaly
mikelbring wrote:What you do is create a text field called url and then hide it with css. Not a hidden field but one hidden with css. If that field has any info in it you simply exit(). The only problem is people without css browsers will 'could' be hurt. I do this on my site and it seems to work like a champ. Might add captcha later on tho.
Maybe I'm just an idiot, but how would that prevent bots from registering? They're generally programmed to fill fields called URL or something?
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 5:00 am
by Stryks
Actually ... I could kind of see that working. The bot is probably going to have a list of ready-made answers for known field names. And even if it doesn't, it'll probably take a shot at all the elements of a form to try and pass validation.
So you hide the field, and if you get a form submitted with the value filled in, you know it's suspect. You could probably tie this method into a profiler, trying to find common elements between all suspect submissions. Even IP info could be useful over a big enough sample (though I wouldn't block anything on IP alone).
Not saying that it'd work ... but it seems an interesting possibility.
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 7:09 am
by taylor28
CAPTCHA would be nice to avoid bots I'd rather avoid bots than CAPTCHA.

Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 8:50 am
by onion2k
Field name randomisation helps too... the first time the form is loaded your "email" field might be called "website", next time it loads it's called "name", and so on. Randomising the field order helps too, so email is the first item one time the form loads, and second another time, etc, but that can have accessibility issues. Coupled with some strict validation it'll defeat most bots though.
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 11:53 am
by califdon
What is the problem we are trying to solve here?
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 12:36 pm
by onion2k
califdon wrote:What is the problem we are trying to solve here?
Automated scripts (bots) filling in forms.
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 2:23 pm
by califdon
onion2k wrote:califdon wrote:What is the problem we are trying to solve here?
Automated scripts (bots) filling in forms.
Yes, I think so, too. It's not avoiding the use of CAPTCHA. That's the point I wanted to make.
So why does the OP not want to use CAPTCHA? It's a pretty well established and widely used method. If we're going to discuss alternatives, we ought to be evaluating why CAPTCHA isn't adequate. Is it user reaction? Does it have any history of being defeated by bots?
Re: How to avoid CAPTCHA ?
Posted: Fri Oct 03, 2008 2:32 pm
by onion2k
califdon wrote:onion2k wrote:califdon wrote:What is the problem we are trying to solve here?
Automated scripts (bots) filling in forms.
Yes, I think so, too. It's not avoiding the use of CAPTCHA. That's the point I wanted to make.
So why does the OP not want to use CAPTCHA? It's a pretty well established and widely used method. If we're going to discuss alternatives, we ought to be evaluating why CAPTCHA isn't adequate. Is it user reaction? Does it have any history of being defeated by bots?
CAPTCHA is
not an adequate method. They're relatively easy to break, progressively more difficult for a user to enter as they get stronger, and they're usually very inaccessible for disabled users. Using a hidden form field, or randomised fields, makes life much harder for a bot and has no effect on the user at all. Much better than a CAPTCHA.