Secure Multi-Tenant Cloud Storage with Homomorphic Encryption

Abstract: Multi-tenant cloud environments present significant security challenges, particularly when handling sensitive data for diverse clients. This study proposes a secure storage architecture utilizing homomorphic encryption (HE) to allow computations on encrypted data while preserving privacy and tenant isolation. The system integrates role-based access control and policy-driven query interfaces to ensure confidentiality and secure access. A simulated multi-tenant environment was used to evaluate performance, measuring latency, throughput, ciphertext overhead, and inter-tenant data leakage. Regression and predictive analysis revealed that ciphertext size and computation depth significantly impact performance metrics. The proposed solution demonstrated an 87% accuracy in encrypted query prediction with negligible leakage, proving that homomorphic encryption can support secure, scalable multi-tenant cloud storage. Keywords Homomorphic Encryption, Multi-Tenant Cloud, Data Privacy, Secure Storage, Confidential Computing, Access Control