Online/Offline Attribute-Based Encryptioin with Multi-Authority Access Control
Shuquan Li, Zhang Huiqi · 2021 18th International Computer Conference on Wavelet Active Media Technology and Information Processing (ICCWAMTIP) · 2021
The CP-ABE access control scheme can effectively implement fine-grained access control. As mobile devices are widely used, plenty of exponential calculations in ciphertexts calculation bring a huge challenge to users who use resource-limited mobile devices. To solve the problem, a decentralized CP-ABE access control scheme with offline/online encryption and outsourced decryption is proposed in this paper. The offline encryption will be accomplished when the device is not in use, which makes encryption faster and more efficient. In the decryption stage, the user will generate the transformed key and hand it over to the honest but curious cloud service provider for decryption preprocessing. The cloud service provider will complete most of the complex exponential calculations, so that the ciphertext can be decrypted quickly and safely by mobile devices. In addition, the scheme supports multi-attribute authority so that the conspiracy attacks can be effectively resisted. It is shown that the scheme can greatly reduce the computing time especially for mobile device users.