Efficient Key Compression in Isogeny‐Based Post‐Quantum Cryptography: A PSO‐WCA Hybrid Optimization Approach

ABSTRACT Isogeny‐based cryptography is an advanced post‐quantum cryptography mechanism. Key compression becomes an important area for Isogeny‐based cryptography systems to perform efficiently. However, an important issue emerges that is connected to the use of large keys in such cryptographic systems. The use of large keys has led to several practical problems, such as key management, storage, and transmission being time‐consuming and resource‐intensive. To tackle all such problems, an innovative and hybrid approach that uses particle swarm optimization and water cycle algorithm optimization for key compression is proposed in this research work to efficiently balance and maintain key size reduction and post‐quantum security. The most important role of particle swarm optimization is to determine the optimization of key compression. On the other hand, the water cycle algorithm primarily concentrates on diversification to maintain security levels. Moreover, this proposed approach also tries to efficiently balance and maintain a reduced key size, which ensures that security levels are focused on side channel and timing attacks. Based on several simulation results, the proposed algorithm successfully calculates the average key size reduction of 45.2%, which is achieved with the fast execution of computation times averaging 175.6 ms for key compression.