Survey and a New Taxonomy of Proofs of Retrievability on the Cloud Storage

Proof of Retrievability (PoR) is a technique used to ensure the authenticity of data on outsourced storage services. It improves the soundness and the robustness of the data integrity scheme and allows clients to recover the remote data. Under the circumstance of considering untrusted parties including the Cloud Storage Provider (CSP) and Third Party Authenticator (TPA), incorporating PoR and zero-knowledge Proofs, which is another technique used to allow a prover to convince a verifier that a secret exists without revealing the secret itself, will ensure client integrity verification, strengthen privacy, and improve fairness to both sides. In this paper, we present, on one hand, the state-of-the-art of PoR under zero-knowledge constructs following an existing data integrity scheme taxonomy of cloud storage. We analyze the PoR scheme formalism and its similarities with zero-knowledge concepts, in addition to the techniques used to settle robustness and zero-knowledge proofs methods. On the other hand, we propose our improved taxonomy of proofs of retrievability enriched by the zero-knowledge, the cryptography model, and the cryptographic setup. The proposed taxonomy equips researchers with a tool to think about the PoR scheme from those perspectives. In the end, we state some fruitful lines of works that PoR can take advantage of; i.e Bulletproofs, Interactive Oracle Proofs, and Interactive Oracle Proofs of Proximity For Reed-Solomon.