TY - GEN
T1 - Broadcast-Optimal Two Round MPC with Asynchronous Peer-to-Peer Channels
AU - Damgård, Ivan
AU - Ravi, Divya
AU - Siniscalchi, Luisa
AU - Yakoubov, Sophia
N1 - Publisher Copyright:
© 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
PY - 2023/9
Y1 - 2023/9
N2 - In this paper we continue the study of two-round broadcast-optimal MPC, where broadcast is used in one of the two rounds, but not in both. We consider the realistic scenario where the round that does not use broadcast is asynchronous. Since a first asynchronous round (even when followed by a round of broadcast) does not admit any secure computation, we introduce a new notion of asynchrony which we call -asynchrony. In this new notion of asynchrony, an adversary can delay or drop up to of a given party’s incoming messages; we refer to as the deafness threshold. Similarly, the adversary can delay or drop up to of a given party’s outgoing messages; we refer to as the muteness threshold. We determine which notions of secure two-round computation are achievable when the first round is -asynchronous, and the second round is over broadcast. Similarly, we determine which notions of secure two-round computation are achievable when the first round is over broadcast, and the second round is (fully) asynchronous. We consider the cases where a PKI is available, when only a CRS is available but private communication in the first round is possible, and the case when only a CRS is available and no private communication is possible before the parties have had a chance to exchange public keys.
AB - In this paper we continue the study of two-round broadcast-optimal MPC, where broadcast is used in one of the two rounds, but not in both. We consider the realistic scenario where the round that does not use broadcast is asynchronous. Since a first asynchronous round (even when followed by a round of broadcast) does not admit any secure computation, we introduce a new notion of asynchrony which we call -asynchrony. In this new notion of asynchrony, an adversary can delay or drop up to of a given party’s incoming messages; we refer to as the deafness threshold. Similarly, the adversary can delay or drop up to of a given party’s outgoing messages; we refer to as the muteness threshold. We determine which notions of secure two-round computation are achievable when the first round is -asynchronous, and the second round is over broadcast. Similarly, we determine which notions of secure two-round computation are achievable when the first round is over broadcast, and the second round is (fully) asynchronous. We consider the cases where a PKI is available, when only a CRS is available but private communication in the first round is possible, and the case when only a CRS is available and no private communication is possible before the parties have had a chance to exchange public keys.
U2 - 10.1007/978-3-031-44469-2_5
DO - 10.1007/978-3-031-44469-2_5
M3 - Article in proceedings
AN - SCOPUS:85174451570
SN - 978-3-031-44468-5
T3 - Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
SP - 87
EP - 106
BT - Progress in Cryptology – LATINCRYPT 2023
A2 - Aly, Abdelrahaman
A2 - Tibouchi, Mehdi
PB - Springer
CY - Cham
T2 - 8th International Conference on Cryptology and Information Security in Latin America, LATINCRYPT 2023
Y2 - 3 October 2023 through 6 October 2023
ER -