A revocable multi-authority fine-grained access control architecture against ciphertext rollback attack for mobile edge computing

Mobile edge computing is an emerging decentralized cloud paradigm that can provide real-time mobile services for users. But there are some limitations in the existing access control architectures for mobile edge computing, such as low efficiency, poor expansibility and high algorithm complexity. Therefore in this paper, we propose a decentralized ciphertext-policy attribute-based encryption scheme which with mutually verifiable outsourced decryption and non-delegated computing mode attribute revocation as the fine-grained access control model for the mobile edge cloud. Compared with the state-of-art access control models with revocation function, first, our scheme is based on Type-3 pairing, which has higher efficiency and stronger security. Second, our outsourcing decryption algorithm can realize mutual verification, that is, not only the server can verify the validity of the user's outsourcing key, but also the user can verify the correctness of the decrypted plaintext. Thirdly, our revocation algorithm can not only resist ciphertext rollback attacks to achieve the genuine backward and forward security, but also does not need the assistance of any intermediate proxy server, which greatly simplifies the network topology. © 2022 Elsevier B.V.