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arXiv · 1503.05144

Piecewise Function Approximation with Private Data

Riccardo Lazzeretti·Tommaso Pignata·Mauro Barni
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Abstract

We present two Secure Two Party Computation (STPC) protocols for piecewise function approximation on private data. The protocols rely on a piecewise approximation of the to-be-computed function easing the implementation in a STPC setting. The first protocol relies entirely on Garbled Circuit (GC) theory, while the second one exploits a hybrid construction where GC and Homomorphic Encryption (HE) are used together. In addition to piecewise constant and linear approximation, polynomial interpolation is also considered. From a communication complexity perspective, the full-GC implementation is preferable when the input and output variables can be represented with a small number of bits, while the hybrid solution is preferable otherwise. With regard to computational complexity, the full-GC solution is generally more convenient.

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Riccardo Lazzeretti, Tommaso Pignata, Mauro Barni. 2015-03-17. Piecewise Function Approximation with Private Data. https://doi.org/10.1109/tifs.2015.2503268

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