A Dynamic Proof of Retrievability (PoR) Scheme With O(logn) Complexity

Cloud storage has been gaining popularity because its elasticity and pay-as-you-go manner. However, this new type of storage model also brings security challenges. This paper studies the problem of ensuring data integrity in cloud storage. In the Proof of Retrievability (PoR) model, after outsourcing the preprocessed data to the server, the client will delete its local copies and only store a small amount of meta data. Later the client will ask the server to provide a proof that its data can be retrieved correctly. However, most of the prior PoR works apply only to static data. The existing dynamic version of PoR scheme has an efficiency problem.