Optimized quantum circuit implementation of SATURNIN for Grover’s algorithm

In 2019, SATURNIN a light-weighted block cipher was proposed for post-quantum security. In this research, we try to examine the security strength of SATURNIN by implementing its quantum circuit to apply Grover’s algorithm for brute-force key search from classical complexity O(N) to quantum complexity O(N/2). We present SATURNIN’s novel quantum structure resource calculation, implementation, and security hardness evaluation based on the NIST proposal for post-quantum security strength. Our proposed quantum circuit implementation requires 872 qubits. As per our evaluation, increasing the number of iterations in this algorithm doesn’t adequately increase its security hardiness against quantum assaults on the IBM QISKIT quantum computer simulator.