Paper 2019/646
Communication-Efficient Unconditional MPC with Guaranteed Output Delivery
Vipul Goyal and Yanyi Liu and Yifan Song
Abstract
We study the communication complexity of unconditionally secure MPC with guaranteed output delivery over point-to-point channels for corruption threshold $t < n/3$. We ask the question: “is it possible to construct MPC in this setting s.t. the communication complexity per multiplication gate is linear in the number of parties?” While a number of works have focused on reducing the communication complexity in this setting, the answer to the above question has remained elusive for over a decade. We resolve the above question in the affirmative by providing an MPC with communication complexity $O(Cn\kappa + n^3\kappa)$ where $\kappa$ is the size of an element in the field, $C$ is the size of the (arithmetic) circuit, and, $n$ is the number of parties. This represents a strict improvement over the previously best known communication complexity of $O(Cn\kappa+D_Mn^2\kappa+ n^3\kappa)$ where $D_M$ is the multiplicative depth of the circuit. To obtain this result, we introduce a novel technique called 4-consistent tuples of sharings which we believe to be of independent interest.
Metadata
- Available format(s)
- Category
- Cryptographic protocols
- Publication info
- A minor revision of an IACR publication in CRYPTO 2019
- Keywords
- Multiparty ComputationInformation-theoretic CryptographyCommunication Complexity
- Contact author(s)
- vipul @ cmu edu,yl2866 @ cornell edu,yifans2 @ andrew cmu edu
- History
- 2019-06-04: received
- Short URL
- https://ia.cr/2019/646
- License
-
CC BY