A novel lightweight hybrid cryptographic framework for secure smart card operations

In this digital age, with exponential usage of smart cards for financial transactions are secured with latest and advanced crypto standards which are prone to advanced cyber threats and quantum attacks. Currently, there are many crypto standards techniques that tend to experience challenges regarding computational overhead, energy requirements, and vulnerable towards modern cyber-attacks. Post-quantum cryptography (PQC) is a crucial necessity to secure financial transactions from the future quantum attacks also. The primary objective is to offer strong security, better performance, and energy efficiency while integrating PQC into prevailing financial transactions. In this article, we propose a novel hybrid crypto standard to enhance the security and privacy of the transactions using smart cards, to achieve this we integrate Elliptic Curve Cryptography Curve25519 to generate secure keys, SPECK block cipher for lightweight encipherment with a powerful hash function for message authentication and integrity checks called PHOTON. Our hybrid model is better than the existing crypto models which need more computational overhead in terms of key length, encryption time, decryption time, energy efficiency that are not fit for lightweight smart card transactions. The proposed hybrid crypto standard shows the considerable performance in terms of various key factors as compared to the several existing hybrid crypto standards. Our standard accomplishes the quick key generation time of 8 ms and minimal energy consumption of 0.34 mJ while preserving the encryption speed of 150 Mbps and decryption speed of 160 Mbps with least memory utilization of 164 KB, our standard key generation time is 88% lesser, encryption time is 25% lesser, decryption time is 27% lesser, energy consumption is 43% lesser, memory utilization is 69% lesser as compared to RSA-2048 + AES-128 hybrid model. Likewise, our model performance is superior to ECDH (P-256) + AES-128 hybrid standard in terms key generation time is 47% lesser, encryption time is 23% lesser, decryption time is 25% lesser, energy consumption is 5% lesser. Based on the experimental outcomes, the proposed hybrid crypto standard is well-suited for lightweight and resource constrained environments such as smart card and IoT applications, posing better performance, low energy utilization, and robust post-quantum security.