Paper Type

Master's Thesis


College of Computing, Engineering & Construction

Degree Name

Master of Science in Computer and Information Sciences (MS)



NACO controlled Corporate Body

University of North Florida. School of Computing

First Advisor

Dr. F. Layne Wallace

Second Advisor

Dr. Robert F. Roggio

Third Advisor

Dr. Karthikeyan Umapathy

Department Chair

Dr. Asai Asaithambi

College Dean

Dr. Mark A. Tumeo


In an increasingly mobile world, the combination of mobile computing devices, publicly accessible Wi-Fi hotspots, and camera phones pose a significant threat to alphanumeric passwords in public environments. Graphical passwords, introduced as an alternative to alphanumerical passwords, help prevent successful shoulder-surfing attacks – covertly observing or recording a password login session, however, most cannot prevent intersection analysis on the data collected through shoulder-surfing. ColorDots is a new graphical password scheme designed to be easy to use and learn, to prevent successful shoulder-surfing attacks, and to hinder intersection analysis. A software implementation of ColorDots is tested, and the results analyzed. This study showed the ColorDots graphical password scheme does prevent shoulder-surfing, and hinders intersection analysis on digital recordings of multiple shoulder-surfing attacks. Furthermore, ColorDots may be just as convenient to use as alphanumeric passwords, while improving password security in public environments.