Secure outsourcing of manufacturing compliance checks.

Compliance data consists of manufacturing quality measures collected in the production process. Quality checks are most of the times computationally expensive to perform, mainly due to the amount of collected data. Having trusted solutions for outsourcing analyses to the Cloud is an opportunity for reducing costs of operation. However, the adoption of the Cloud computation paradigm is delayed for the many security risks associated with it. In the use case we consider in this paper, compliance data is very sensitive, because it may contain IP-critical information, or it may be related to safety-critical operations or products. While the technological solutions that protect data in-transit or at rest have reached a satisfying level of maturity, there is a huge demand for securing data in-use. Homomorphic Encryption (HE) is one of the main technological enablers for secure computation outsourcing. In the last decade, HE has reached maturity with remarkable pace. However, using HE is still far from being an automated process and each use case introduces different challenges. In this paper, we investigate application of HE to the described scenario. In particular, we redesign the compliance check algorithm to a HE-friendly equivalent. We propose efficient data input encoding that takes advantage of SIMD type of computations supported by the CKKS HE scheme. Moreover, we introduce security/performance trade-offs by proposing limited but acceptable information leakage. We have implemented our solution using SEAL HE library and evaluated our results in terms of time complexity and accuracy. Finally, we analyze the benefits and limitations of integration of a Trusted Execution Environment for secure execution of some computations that are overly expensive for the chosen HE scheme. [ABSTRACT FROM AUTHOR]