Jackpot: Non-Interactive Aggregatable Lotteries

Nils Fleischhacker; Mathias Hall-Andersen; Mark Simkin; Benedikt Wagner

Paper 2023/1570

Jackpot: Non-Interactive Aggregatable Lotteries

Nils Fleischhacker

, Ruhr University Bochum

Mathias Hall-Andersen

, Aarhus University

Mark Simkin

Benedikt Wagner

, CISPA Helmholtz Center for Information Security, Saarland University

Abstract

In proof-of-stake blockchains, liveness is ensured by repeatedly selecting random groups of parties as leaders, who are then in charge of proposing new blocks and driving consensus forward, among all their participants. The lotteries that elect those leaders need to ensure that adversarial parties are not elected disproportionately often and that an adversary can not tell who was elected before those parties decide to speak, as this would potentially allow for denial-of-service attacks. Whenever an elected party speaks, it needs to provide a winning lottery ticket, which proves that the party did indeed win the lottery. Current solutions require all published winning tickets to be stored individually on-chain, which introduces undesirable storage overheads. In this work, we introduce {non-interactive aggregatable lotteries} and show how these can be constructed efficiently. Our lotteries provide the same security guarantees as previous lottery constructions, but additionally allow any third party to take a set of published winning tickets and aggregate them into one short digest. We provide a formal model of our new primitive in the universal composability framework. As one of our main technical contributions, which may be of independent interest, we introduce aggregatable vector commitments with simulation-extractability and present a concretely efficient construction thereof in the algebraic group model in the presence of a random oracle. We show how these commitments can be used to construct non-interactive aggregatable lotteries. We have implemented our construction, called {Jackpot}, and provide benchmarks that underline its concrete efficiency.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Preprint.
Keywords: Lotteries Aggregation Vector Commitments Simulation-Extractability KZG Commitments
Contact author(s): mail @ nilsfleischhacker de
ma @ cs au dk
mark simkin @ ethereum org
benedikt wagner @ cispa de
History: 2023-10-13: approved; 2023-10-11: received; See all versions
Short URL: https://ia.cr/2023/1570
License: CC BY

BibTeX

@misc{cryptoeprint:2023/1570,
      author = {Nils Fleischhacker and Mathias Hall-Andersen and Mark Simkin and Benedikt Wagner},
      title = {Jackpot: Non-Interactive Aggregatable Lotteries},
      howpublished = {Cryptology ePrint Archive, Paper 2023/1570},
      year = {2023},
      note = {\url{https://eprint.iacr.org/2023/1570}},
      url = {https://eprint.iacr.org/2023/1570}
}