Multi-Provider Secure Processing of Sensors Data

We describe the implementation of an approach for supporting secure query processing over sensors data in a multi-provider scenario. Our solution relies on the definition of authorizations regulating access to data according to three different visibility levels (no visibility, encrypted visibility, and plaintext visibility). Data processing is performed by multiple providers based on the restrictions imposed by authorizations, which may require to adjust data visibility on the fly. We describe the structure of the query optimizer and show how the operations of a computation can be assigned to different cloud providers to build an efficient, secure, and economical plan for collaborative data processing.