Compressed Sigma-Protocols for Bilinear Group Arithmetic Circuits and Application to Logarithmic Transparent Threshold Signatures

Recent developments in zero-knowledge have yielded various communication-efficient protocols for proving correctness of statements captured by arithmetic circuits. Since any relation can be translated into an arithmetic circuit relation, these primitives are extremely powerful and widely applied. However, this translation often comes at the cost...

Brief Announcement: Malicious Security Comes for Free in Consensus with Leaders

We consider consensus protocols in the model that is most commonly considered for use in state machine replication, as initiated by Dwork-Lynch-Stockmeyer, then by Castro-Liskov in 1999 with “PBFT”. Such protocols guarantee, assuming n players out of which t < n/3 are maliciously corrupted, that the honest players output the same valid value...