Captchas: The Bear Proof Trash Can Problem

Sun, 21 Nov 2010 23:03:00 +0000

Lately I’ve been selling a lot of things on Craigslist. Along with adventures in capitalism, every post to Craigslist requires filling out a CAPTCHA, specifically a reCAPTCHA. I’ve noticed that they have gotten quite difficult. In fact, at least one of the captchas I got recently was in Greek.

Captchas area a really clever idea, but they represent a special kind of arms race. The spammers are always improving their automatic and semi-automatic captcha solvers. At the same time, the average web user is not getting any better at solving captchas. The goal of the captcha company is to hit the window between what motivated spammers can do automatically and what web users can do manually.

Metaphor on Bulrush Labs — Richard Tibbetts

Captchas: The Bear Proof Trash Can Problem