Secure Dynamic Groups Data Sharing with Modified Revocable Attribute-Based Encryption in Cloud

Abstract

Cloud computing provides a flexible and convenient way for data sharing, which brings various benefits for both the society and individuals. But there exists a natural resistance for users to directly outsource the shared data to the cloud server since the data often contain valuable information. Although it causes many security issues, cloud service providers are not at the same level of trust as users. To preserve the privacy of data against non-trusted Cloud Service Provider (CSP) files, current solutions implement Cryptographic methods (for example, encryption methods) and deliver decryption keys only to authorized users. However, data sharing in the cloud among authorized users remains a difficult problem, especially when it comes to dynamic user groups. Most of the research on dynamic group data exchange has been done in the cloud with many algorithms, such as Attribute-Based Encryption (ABE), Ciphertext Attribute-Based Encryption (CP-ABE) to provide better security in dynamic cloud users with multiple authorities, but they still face challenges, either lack of performance or rely on a trusted server, and are not suitable for distribution with the problem of eliminating attributes. Thus, the Revocation user cannot get shared data before and after. To solve this in particular, we first suggest an effective Modified Revocable Attribute-Based Encryption (MR-ABE) system with the quality of ciphertext allocation by applying and integrating both Identity-Based Encryption (IBE) and CP-ABE techniques. It can provide confidential forward / backward of encrypted data by delivering user revocation attributes and updating encrypted text simultaneously. Next, we perform Fine-grained access control and data exchange for on-demand services with dynamic user groups on the cloud. Experimental data show that our proposed system is more efficient and scalable than the latest generation solutions.