Secure File Storage on Cloud Using Hybrid Cryptography

Abstract The exponential growth of cloud computing is the reason that people and organizations store and then access their data. Primary concerns persist regarding data's security as well as integrity stored in cloud environments because of cyber-attacks' increasing threat landscape. Elliptic Curve Cryptography (ECC) combines with ChaCha20 for secure key exchange; an efficient stream cipher, and blockchain technology ensures tamper-proof file integrity verification in this paper proposing a novel security framework for cloud file storage. ChaCha20 resists against cryptographic attacks and then runs fast, while then ECC manages the keys securely and lightly. Blockchain integration adds a permanent stage to check file integrity stored in the cloud ensuring that forbidden alterations are never overlooked. Encryption as well as decryption performance is a key evaluation factor for the system that is proposed. Also evaluation factors are verification of file integrity and security of the overall system. The results show that the hybrid cryptographic approach offers toward a highly efficient and secure solution for cloud storage applications. Since it is coupled with blockchain, it addresses both confidentiality and integrity concerns.