Malicious Security Comes Free in SPDZ

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We study the communication complexity of SPDZ-type MPC protocols in the dishonest majority setting with maximum corruption, where $t=n-1$ out of $n$ parties can be corrupted. In the semi-honest setting, the state-of-the-art SPDZ protocol achieves an amortized communication cost of $4n$ field elements per multiplication gate, assuming a pseudorandom correlation generator (PCG) that prepares random Beaver triples silently in the offline phase. However, achieving security against malicious adversar