Cloud auditing for outsourced storage service in healthcare systems with static data transfer

The rapid development and wide adoption of electronic healthcare systems provide huge conveniences for the users. The health records are normally outsourced to a server for centralized management. To ensure data integrity, auditing techniques are promising candidates to be applied. In practice, there is always a need to transfer data, such as when the user changes the hospital or medical center. Moreover, how to provide efficient data transfer and not bring complicated transfer process for auditing should be given attention. For traditional data transfer processes, the tags need to be recomputed or updated and then stored on the server. The scheme we proposed in this paper has the property that the tags remain the same during data transfer. This process is referred to as static transfer since the data and tags do not change. In addition, the basic construction is built upon Shacham-Waters auditing, which is the foundation of the homomorphic linear authenticator (HLA). Therefore, our scheme is compatible with other optimizations for HLA schemes, such as the evolution tag technique proposed recently to achieve a compact tag. To show the effectiveness of our scheme, we combined the evolution tag and our construction to achieve static data transfer functionality and compact tag efficiency. The improvement in our scheme preserves the underlying HLA structure and hence does not complicate the tag generation, challenge, and response phases while achieving static data transfer.