Chaos-Based Synchronous Nonce Generation for Enhancing ATM Card Transaction Security

Automated Teller Machines (ATMs) are fast transforming the financial transaction process into something easier and more accessible to banking areas. While fraud on these systems is mitigated, consumers and institutions are still susceptible to skim and replay attacks, resulting in loss. Often, existing static PINs and conventional encryption protocols are not effective ways to address these problems. This research investigates a chaos-based approach to improve ATM security to address these challenges. Given the chaotic nature of the inherent unpredictability of the chaos theory, a secure nonce generation algorithm developed is synchronized between ATM cards and server systems without direct communication. A logistic map is used to generate high entropy nonces by the system, and encryption mechanisms are integrated to protect data transmission. The algorithm is experimentally analyzed, obtaining an entropy score of 7.98 out of 8, 100% synchronization accuracy, and 0.0025 seconds per nonce execution time. It also demonstrates good resistance against replay attacks, brute force attempts, and interception risks, whilst its security and scalability exceed those of standard techniques. A chaos-based approach presented here is a strong first step to address vulnerabilities found in ATM systems and mitigate ATM fraud. This guarantees a reliable synchronous process, improved cryptographic robustness and practicality of the secure financial transactions. The implications of these findings for ATM and digital security systems are underscored by the potential of chaos theory as a powerful tool.