Zero trust anonymous access algorithm for multi cloud storage system based on CP-ABE

This paper proposes a zero-trust anonymous access algorithm for multi-cloud storage systems based on CP-ABE (Ciphertext-Policy Attribute-Based Encryption). To address the challenges of inefficient data encryption/decryption and high communication overhead in existing systems, we design a novel access control model that integrates hierarchical identity-based encryption with enhanced CP-ABE. The model features: (1) a hierarchical identity management module for standardized authentication, (2) server-side data encryption enabling fine-grained access control, and (3) an improved CP-ABE scheme with key versioning for efficient revocation. Experimental results demonstrate that the proposed algorithm significantly improves encryption/decryption efficiency while reducing storage overhead and enhancing data-sharing security compared to conventional approaches.