Introduction

In order to protect on line services form malicious attacks, access is only granted to users by solving a CAPTCHA (Completely Automated Public Turing Test to Tell Computers and Humans Apart) to  distinguish a human user from a malicious software robot. This patented image-based CAPTCHA relies on the human ability to recognize shapes in a confused environment. It is user friendly and resilient to automated attacks.

Technical features

The main purpose of a CAPTCHA is to distinguish a human user from a software robot (or “bot”) that runs automated tasks. A CAPTCHA is a program that generates a test, that can be easily solved by humans, but not by a bot. For example, a bot cannot easily understand the meaning of a sentence (or a picture), while humans can carry out this task with negligible effort. A good CAPTCHA must be user-friendly and at the same time offer resiliency against automated attacks.

This patented image-based CAPTCHA relies on user interaction because it depends on the innate human ability to recognize shapes in a confused environment. It was thoroughly tested to evaluate the two key aspects of a CAPTCHA: the usability, by carrying out a user study; the resiliency against traditional, specifically designed, and machine learning based automated attacks. The results is a user friendly CAPTCHA resilient to automated attacks.

Possible Applications

• Internet service security against malicious bot attacks.

Advantages

• User friendly;
• Effective resilience from automated bot attacks;
• Improves internet service security.