New publication in International Journal of Information Security [09.01.24]
Christian Krupitzer from the Department of Food Informatics is Co-Author of the publication "De Bello Homomorphico: Investigation of the extensibility of the OpenFHE library with basic mathematical functions by means of common approaches using the example of the CKKS cryptosystem" in International Journal of Information Security (Impact Factor: 3.2 (2022)).
The publication "De Bello Homomorphico: Investigation of the extensibility of the OpenFHE library with basic mathematical functions by means of common approaches using the example of the CKKS cryptosystem" by Thomas Prantl (University of Würzburg, Würzburg, Germany) with the co-authors, Lukas Horn (University of Würzburg, Würzburg, Germany), Simon Engel (University of Würzburg, Würzburg, Germany), Lukas Iffländer (University of Würzburg, Würzburg, Germany), Lukas Beierlieb (University of Würzburg, Würzburg, Germany), Christian Krupitzer (Department of Foodinformatics (150L), and Computational Science Hub (CSH), University of Hohenheim, Stuttgart, Germany), André Bauer (University of Chicago, Chicago, IL, USA), Mansi Sakarvadia (University of Chicago, Chicago, IL, USA), Ian Foster (University of Chicago, Chicago, IL, USA), Samuel Kounev (University of Würzburg, Würzburg, Germany) was published in International Journal of Information Security, Springer (Impact Factor: 3.2 (2022)).
Cloud computing has become increasingly popular due to its scalability, cost-effectiveness, and ability to handle large volumes of data. However, entrusting (sensitive) data to a third party raises concerns about data security and privacy. Homomorphic encryption is one solution that allows users to store and process data in a public cloud without the cloud provider having access to it. Currently, homomorphic encryption libraries only support addition and multiplication; other mathematical functions must be implemented by the user. To this end, we discuss and implement the division, exponential, square root, logarithm, minimum, and maximum function, using the CKKS cryptosystem of the OpenFHE library. To demonstrate that complex applications can be realized with this extended function set, we have used it to homomorphically realize the Box–Cox transform, which is used in many real-world applications, e.g., time-series forecasts. Our results show how the number of iterations required to achieve a given accuracy varies depending on the function. In addition, the execution time for each function is independent of the input and is in the range of ten seconds on a reference machine. With this work, we provide users with insights on how to extend the original restricted function set of the CKKS cryptosystem of the OpenFHE library with basic mathematical functions.
The publication is available at: link.springer.com/article/10.1007/s10207-023-00781-0
