Reducing Communication Channels in MPC

© 2018, Springer Nature Switzerland AG. We show that the recent, highly efficient, three-party honest-majority computationally-secure MPC protocol of Araki et al. can be generalised to an arbitrary Q2 access structure. Part of the performance of the Araki et al. protocol is from the fact it does not use a complete communication network for the most costly part of the computation. Our generalisation also preserves this property. We present both passively- and actively-secure (with abort) variants of our protocol. In all cases we require fewer communication channels for secure multiplication than Maurer’s “MPC-Made-Simple” protocol for Q2 structures, at the expense of requiring pre-shared secret keys for Pseudo-Random Functions.status: publishe