A Multiauthority CP-ABE Scheme With Fully Outsourced Computation and Direct Attribute Revocation Based on the R-LWE Problem in Edge Computing

Existing Ciphertext Policy Attribute-Based Encryption (CP-ABE) schemes based on the Ring Learning with Errors (R-LWE) problem have issues such as key escrow, insufficient real-time performance for attribute revocation, high computational cost and high storage overhead, making them unsuitable for use in distributed edge computing scenarios characterised by frequent changes in user attributes and limited terminal computing and storage resources. To address the above issues, we propose a multi-authority CP-ABE scheme with fully outsourced computation and attribute direct revocation based on the R-LWE problem. In our scheme, the use of a multi-authority management mechanism effectively avoids the key escrow problem, the use of a direct attribute revocation mechanism allows flexible revocation of user attributes, and the use of fully outsourced computation significantly reduces user computing costs and storage overhead. Security and experimental analysis have shown that our scheme satisfies indistinguishability under chosen plaintext attacks in the standard model and can significantly reduce the computational cost and storage overhead for users.