PRE as a Service within Smart Grid City

International audienceIn the context of Smart Grid Cities, legal obligations require that certain personal data must be stored in the long term and protected. To deal with confidentiality issues, we use the concept of Proxy Re-Encryption (PRE) which allows sharing encrypted data. We present the first implementation of the Chow’s algorithm, and propose an optimized instantiation thanks to elliptic curves. This is the first unidirectional algorithm with CCA security that does not rely on pairing, which guarantees its high performance. This allows its use in real conditions. We have implemented it in JavaScript for direct use in a web browser by the user. In order to be able to process the data asynchronously, we then define the notion of PREaaS (Proxy Re-Encryption as a Service) that also allows use in a service-oriented context