Secure and Scalable Cloud Storage with Dynamic AES and Blockchain-Based Key Management with CHACHA20 Optimization

Abstract

This study proposes an advanced cloud data security solution that combines blockchainbased decentralized key management, dynamic AES encryption, and CHACHA20 optimization. Unlike traditional systems, encryption keys are generated dynamically using XOR operations on file hashes and blockchain block hash values, ensuring unique and incredibly secure encryption for each file. By offering distributed, tamper-proof encryption key storage, blockchain technology removes insider threats and single-point failure. Additionally, the suggested modification improves computational speed and enables compatibility for all file formats by substituting the lightweight CHACHA20 algorithm for AES and ECC. Because testing results demonstrate enhanced security strength, reduced encryption time, better scalability, and superior performance in resource-constrained scenarios, the method is suitable for real-world cloud applications.