Implementation of CAPTCHA suitable for mobile devices

Abstract

CAPTCHA is a technology designed to prevent automated programs (known as bots) from acquiring access to on-line accounts to send spam mail, manipulate vote numbers in on-line polls, or take other malicious actions. In addition, access to Web services has been incorporated into mobile devices, such as smartphones. However, because most CAPTCHAs are not designed for mobile devices, user-friendly CAPTCHA for mobile devices is required. Thus, we implemented CAPTCHA on mobile devices and evaluated its resistance to bots. Our CAPTCHA showed robustness against bots, with good usability. Fig. 3. Results of breakthrough rate for the first version (top) and improved version (bottom).

Interactive Handwritten and Text-Based Handwritten Arabic CAPTCHA Schemes for Mobile Devices: A Comparative Study

“…Author proposes more than one method of CAPTCHA test, depends on request from users to select a specific country location, specific color, and drag until the end of the test. In addition, Aburada et al [28] proposed a new CAPTCHA suitable for mobile devices and discussed its practicality. Although these studies proposed CAPTCHA schemes for mobile devices, but their formulations do not fit exactly with our approach in terms of handwritten Arabic CAPTCHA.…”

“…Study Limitation [7] This study proposed a method that is limited in the sense that a finite number of Arabic words from a pre-collected database were used [4] There is a lack of the robustness evaluation in this study in which the OCRs are only used and more sophisticated methods can be used such as an automated segmentation algorithm attack and machine learning approaches [2] The proposed generator in this study has not been tested on smartphones, as we aim in this paper [3] The proposed scheme in this study has not been tested on smartphones, as we aim in this paper [8], [9], [24], [28] Although these studies proposed CAPTCHA schemes for mobile devices, but their formulations do not fit exactly with our approach in terms of handwritten Arabic CAPTCHA.…”