Trifecta: Faster High-Throughput Three-Party Computation over WAN Using Multi-Fan-In Logic Gates.

Multi-party computation (MPC) has been a very active area of research, and recent industrial deployments exist. Practical MPC is currently limited to low-latency, high-throughput network setups, i.e., local-area networks (LAN). However, many use cases require the participation of different entities located in different data centers, i.e., communication over wide-area networks (WAN). Although, constant-round MPC exists, it has very high communication cost. In this paper we investigate the reduction of the round complexity of secret-shared based multi-party computation. We propose a new three-party computation protocol that allows to compute multi-fan-in gates in one round without any precomputation. Our protocol outperforms related work, including constant-round protocols, over WANs. For example, we improve throughput of AES-128 over WAN by a factor of more than 2.2x compared to related work.