Usability and Robustness Evaluation of Popular Electronic Services’ CAPTCHA in Saudi Arabia

Abstract

Abstract. Web-based services have been utilized to facilitate many electronic government services that may be exposed to attacks based on some automated tools. In order to prevent these attacks, a method has been proposed to distinguish between humans and bots users. This method is a CAPTCHA, which stands for Completely Automated Public Turing test to tell Computers and Humans Apart. It is a mechanism which is widely used nowadays for protecting web-based services from malicious users and automated spammers. A good CAPTCHA should be usable and robust. Since electronic services (e-services) have recently been released in Saudi Arabia, this paper investigates the usability and robustness aspects of CAPTCHAs that are applied in a number of these services. The results showed that several applied CAPTCHA schemes in some e-services in Saudi Arabia need an improvement in terms of both usability and robustness aspects.