2 research outputs found
The Round Complexity of General VSS
The round complexity of verifiable secret sharing (VSS) schemes has been studied extensively for threshold adversaries. In particular, Fitzi et al. showed an efficient 3-round VSS for \cite{FitziVSSTCC06}, where an infinitely powerful adversary can corrupt t (or less) parties out of parties. This paper shows that for non-threshold adversaries,
-Two round VSS is possible iff the underlying adversary structure
satisfies condition;
-Three round VSS is possible iff the underlying adversary structure
satisfies condition.
Further as a special case of our three round protocol, we can obtain a more efficient 3-round VSS than the VSS of Fitzi et al. for . More precisely, the communication complexity of the reconstruction phase is reduced from to . We finally point out a flaw in the reconstruction phase of VSS of Fitzi et al., and show how to fix it