Grotto: Screaming fast $(2 + 1)$-PC for $\mathbb{Z}_{2^{n}}$ via (2, 2)-DPFs

ePrint Report: Grotto: Screaming fast $(2 + 1)$-PC for $\mathbb{Z}_{2^{n}}$ via (2, 2)-DPFs

Kyle Storrier, Adithya Vadapalli, Allan Lyons, Ryan Henry

We introduce Grotto, a framework and C++ library for space- and time-efficient $(2+1)$-party piecewise polynomial (i.e., spline) evaluation on secrets additively shared over $\mathbb{Z}_{2^{n}}$. Grotto improves on the state-of-the-art approaches based on distributed comparison functions (DCFs) in almost every metric, offering asymptotically superior communication and computation costs with the same or lower round complexity. At the heart of Grotto …

art communication computation distributed eprint report evaluation fast framework functions library lyons party report secrets space state