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Multiparty computation unconditionally secure against Q^2 adversary structures

Adam Smith·Anton Stiglic
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Abstract

We present here a generalization of the work done by Rabin and Ben-Or. We give a protocol for multiparty computation which tolerates any Q^2 active adversary structure based on the existence of a broadcast channel, secure communication between each pair of participants, and a monotone span program with multiplication tolerating the structure. The secrecy achieved is unconditional although we allow an exponentially small probability of error. This is possible due to a protocol for computing the product of two values already shared by means of a homomorphic commitment scheme which appeared originally in a paper of Chaum, Evertse and van de Graaf.

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Adam Smith, Anton Stiglic. 1999-02-08. Multiparty computation unconditionally secure against Q^2 adversary structures. https://arxiv.org/abs/cs/9902010

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