ADAMAS: Interweaving unicode and color to enhance CAPTCHA security

作者：Roshanbin Narges^*; Miller James

来源：Future Generation Computer Systems-The International Journal of eScience, 2016, 55: 289-310.

DOI：10.1016/j.future.2014.11.004

• CAPTCHA
• UNICODE
• Color
• Interactive CAPTCHAs
• CAPTCHA security
• CAPTCHA usability

We propose, implement and test a new CAPTCHA, called Adamas, which offers resistance against preprocessing and various forms of segmentation and recognition attacks. The multi-layered security approach employed in this CAPTCHA mainly comes from its use of Unicode as an input space, a virtual keyboard as the input device, homoglyphs and correlated usage of color in foreground and background as well as several layers of randomization that aim to minimize the formation of detectable patterns that can be exploited by machines. A user study conducted to measure the usability of Adamas indicates that its solving accuracy is comparable to major CAPTCHAs in use today and offers insights into factors that affect CAPTCHA usability.

• 出版日期2016-2