Visible to the public Cloud Storage File Recoverability

TitleCloud Storage File Recoverability
Publication TypeConference Paper
Year of Publication2017
AuthorsGorke, Christian A., Janson, Christian, Armknecht, Frederik, Cid, Carlos
Conference NameProceedings of the Fifth ACM International Workshop on Security in Cloud Computing
Conference LocationNew York, NY, USA
ISBN Number978-1-4503-4970-3
KeywordsCloud Security, cloud storage, Metrics, proofs of recoverability, proofs of retrievability, pubcrawl, resilience, Resiliency, Scalability, user behavior, user privacy in the cloud

Data loss is perceived as one of the major threats for cloud storage. Consequently, the security community developed several challenge-response protocols that allow a user to remotely verify whether an outsourced file is still intact. However, two important practical problems have not yet been considered. First, clients commonly outsource multiple files of different sizes, raising the question how to formalize such a scheme and in particular ensuring that all files can be simultaneously audited. Second, in case auditing of the files fails, existing schemes do not provide a client with any method to prove if the original files are still recoverable. We address both problems and describe appropriate solutions. The first problem is tackled by providing a new type of "Proofs of Retrievability" scheme, enabling a client to check all files simultaneously in a compact way. The second problem is solved by defining a novel procedure called "Proofs of Recoverability", enabling a client to obtain an assurance whether a file is recoverable or irreparably damaged. Finally, we present a combination of both schemes allowing the client to check the recoverability of all her original files, thus ensuring cloud storage file recoverability.

Citation Keygorke_cloud_2017