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arXiv · 0706.2010

Information-theoretic security without an honest majority

Anne Broadbent·Alain Tapp
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Abstract

We present six multiparty protocols with information-theoretic security that tolerate an arbitrary number of corrupt participants. All protocols assume pairwise authentic private channels and a broadcast channel (in a single case, we require a simultaneous broadcast channel). We give protocols for veto, vote, anonymous bit transmission, collision detection, notification and anonymous message transmission. Not assuming an honest majority, in most cases, a single corrupt participant can make the protocol abort. All protocols achieve functionality never obtained before without the use of either computational assumptions or of an honest majority.

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Anne Broadbent, Alain Tapp. 2007-06-13. Information-theoretic security without an honest majority. https://doi.org/10.1007/978-3-540-76900-2_25

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