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Re: Plug and play alternatives to captcha

for

From: Aaron Cannon
Date: Apr 17, 2008 1:50PM

If I am not mistaken, the ATM does not "read" the hand writing as such. It simply stores a digital image of it for the banks records.

However, this captcha issue has been bothering me for some time. There _must_ be a way for a computer to tell humans and computers apart, without relying on any of the physical senses of sight or hearing. I just can't for the life of me think of what it could be.

The solutions offered so far all either require the use of hearing, or aren't true captchas. I, for example, would argue that a system that randomly asks simple questions is not a true captcha, because when all is said and done, it is not the computer asking the questions. It is a human asking the questions through the computer. It is my belief that for a system to be a true captcha, the question has to be generated by the computer. Likewise, for the system to be a good captcha, the probability of getting the right answer through random guessing must be very small, and the question pool must be astronomically large. In short, we have to figure out a way for the computer to ask millions of questions that it can't answer but that a human of average to low intelligence and only the ability to read can answer. Obviously, not a small challenge, and potentially impossible, though I tend to doubt the latter.

The other problem with the offered solutions, aside from good audio captcha, is the problem of crackability. Current captchas are by no means perfect, but they are at least difficult to crack. The same, sadly, can not be said for the offered solutions. As has been mentioned, this is not a problem for the smaller sites, but what's a big name site to do? Big name = big target, and some times, some sort of captcha is the only viable option.

Aaron


>>> "Randall Pope" < <EMAIL REMOVED> > 4/17/2008 1:36 PM >>>

Mike,

Thank for the lanais of re-captcha. Being deaf-blind myself, you're quite
right it's very inaccessible. Even the low vision will have problem reading
or listen to any captcha.

Another thought: If the ATMs at the local banks are able to scan and read
the handwriting on the checks being deposit, I would have to assume the
today's scanners will read the captcha writing as well. With that
assumption I would say that Jared's approach would be the best route.

Randy Pope who is deaf-blind