A Novel Two-Factor Authentication Scheme Based on QR Code Prompt

Ensuring online safety and security is critical as personal data grow increasingly valuable, necessitating robust authentication to protect users from potential threats. The use of current authentication mechanisms often fails to balance user convenience, cost effectiveness, and robustness. This paper addresses these challenges with a two-factor authentication scheme that leverages QR codes embedded with an encoded prompt in the form of a question-and-answer pair. The primary objective is to enhance security by verifying human presence through user interaction with geometrical patterns displayed on the QR code. Upon scanning the QR code, the user accesses a question and references the geometrical patterns shown on the QR code to answer, verifying human presence and mitigating risks of unauthorized access. The shape patterns on QR codes are tested for user perceptions regarding shape clarity, visual esthetics, and QR code scannability. Experiments demonstrate that shape width, size, and position outlines are interrelated with QR code versions or module sizes. For small versions (v1–5) achieved 92% user satisfaction and 89% scan success with centrally placed shapes and 3–5 px outlines, while larger versions (v10–15) attained 94% visual clarity and 96% scan success using randomly distributed shapes with 1–2 px outlines, resulting in a 40% reduction in authentication time compared to SMS-based OTP. This authentication QR code design is competitive in terms of construction cost and efficiency compared with other multi-factor authentication mechanisms for user verification.