Enhancing the Security of Personal Identification Numbers with Three-Dimensional Displays

Passwords and personal identification numbers (PINs) are convenient and ubiquitous, but they are quite vulnerable to attackers who stand near the user ("shoulder-surfers"). This problem may be partially resolved by changing the user interface, but previous solutions of this kind still give shoulder-surfing attackers a significant advantage over brute force search. This paper provides a novel solution based on three dimensions, particularly suitable for glasses-free three-dimensional (3D) displays found in many smartphones and handheld game consoles. A user at the "3D spot" may log in easily, while nearby shoulder-surfers gain no advantage. A detailed experimental usability analysis is performed to demonstrate the effectiveness of the proposed scheme in comparison to the existing methods.