Efficient Revocable Attribute-Based Encryption with Hidden Policies

We present a novel Ciphertext-Policy Attribute-Based Encryption (CP-ABE) scheme, which bridges the gap between highly dynamic (industrial) environments and resource-constrained devices. Our construction combines outsourced-decryption, hidden policies and revocation, to cope with the requirements posed by such environments. In contrast to existing schemes, which typically rely on composite order bilinear groups, we present a scheme in prime order groups. The resulting scheme is more efficient as it relies on smaller group orders. We prove our scheme secure under the Symmetric External Diffie-Hellman (SXDH) assumption. Lastly, we compare our scheme against existing schemes and provide timing results of our software implementation. Our evaluation shows that the proposed scheme is flexible enough for the targeted environment while improving performance by an order of magnitude.