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SmartCast: An Incentive Compatible Consensus Protocol Using Smart Contracts

  • Abhiram KothapalliEmail author
  • Andrew Miller
  • Nikita Borisov
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10323)

Abstract

Motivated by the desire for high-throughput public databases (i.e., “blockchains”), we design incentive compatible protocols that run “off-chain”, but rely on an existing cryptocurrency to implement a reward and/or punishment mechanism. Our protocols are incentive compatible in the sense that behaving honestly is a weak Nash equilibrium, even in spite of potentially malicious behavior from a small fraction of the participants (i.e., the BAR model from Clement et al. [7]). To show the feasibility of our approach, we build a prototype implementation, called SmartCast, comprising an Ethereum smart contract, and an off-chain consensus protocol based on Dolev-Strong [10]. SmartCast also includes a “marketplace” smart contract that randomly assigns workers to protocol instances. We evaluate the communication costs of our system, as well as the “gas” transaction costs that are involved in running the Ethereum smart contract.

Keywords

Atomic broadcast TRB Game theory Ethereum Smart contracts 

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Copyright information

© International Financial Cryptography Association 2017

Authors and Affiliations

  • Abhiram Kothapalli
    • 1
    Email author
  • Andrew Miller
    • 1
  • Nikita Borisov
    • 1
  1. 1.University of Illinois at Urbana-ChampaignUrbanaUSA

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