IB-IADR: Enabling Identity-Based Integrity Auditing and Data Recovery With Fault Localization for Multicloud Storage

With the increasing prevalence of network cloud storage, an escalating number of users are choosing to entrust their data to the cloud. To guarantee remote data integrity and mitigate irreversible loss in case of a single point of failure, numerous multi-cloud public auditing schemes have been proposed. However, most existing studies primarily focus on storage architectures with multiple copies. In practice, users are required to distribute identical data replicas individually across multiple cloud servers (CSs), resulting in significant communication overhead and substantial consumption of storage resources on these servers. Moreover, there is a lack of secure public auditing schemes that effectively address both fault localization and data recovery challenges. To address these issues and enhance storage data reliability, this paper proposes an identity-based integrity auditing and data recovery scheme with fault localization for multi-cloud storage (hereafter referred to as IB-IADR). Specifically, we design a novel identity-based homomorphic signature to facilitate a lightweight auditing challenge-verification process. Our scheme ensures the uniform distribution of encoded data while minimizing data redundancy across multiple CSs. Additionally, IB-IADR provides robust data recovery capabilities and supports fast and accurate fault localization features, including entity position, file position and data block position. We demonstrate that our scheme is provably secure against forgery attacks on response auditing proofs, based on the hardness assumption of the standard CDH problem and DDH problem. We evaluate the proposed scheme's performance to demonstrate its utility in multi-cloud storage environments.