The Opera’s Not Over Until The Fat Lady Sings
They changed their tune over at my.opera.com on 10 March 2007 and the image-based CAPTCHA was replaced with a text-based one. No doubt the folks at Opera were tired of dealing with SPAM Bots that danced their way around the CAPTCHA images, so they decided to give text phrases a try.
This is actually the first time that I’ve seen a major popular site working with text-based CAPTCHA, and I was kind of surprised. Popular sites like my.opera.com are often the targets of specialized SPAM Bots that are designed specifically to defeat that one site’s defenses. Apparently the text gates are holding strong in this case, because they are still employing it.
Even so, the developers at my.opera.com have likely installed a second level of protection designed to kick in should unusual activity be noted. That’s the kind of defensive thinking you have to employ when you run a popular destination site.
Text-based CAPTCHA, like Advanced Textual Confirmation (ATC), wins hands-down over image-based schemes because it is smarter than the SPAM Bots, but not so smart that humans have a problem navigating it.
As you probably know, it’s not necessary for a text-based system like ATC to be so complicated that normal human beings can’t unlock the door. It just has to be smarter than SPAM Bots that depend upon character and pattern recognition schemes, and plain brute force, to huff and puff and blow the door down.
ACD is smart enough to stay ahead of the spammers, and that’s all that needs to happen to get the job done. That sort of reminds me of the two guys that were being chased by a bear. One of them quickly figured out the secret of avoiding being eaten alive. You can learn that secret and see how it applies to spam protection, by clicking here.