Game-Theoretic Analysis of an Incentivized Verifiable Computation System

  • Mahmudun NabiEmail author
  • Sepideh Avizheh
  • Muni Venkateswarlu Kumaramangalam
  • Reihaneh Safavi-Naini
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11599)


Outsourcing computation allows a weak client to outsource its computation to a powerful server and receive the result of the computation. Verifiable outsourcing enables clients to verify the computation result of untrusted servers. Permissionless distributed outsourcing systems provide an attractive marketplace for users to participate in the system as a problem-giver who needs solution to a problem, or problem-solver who is willing to sell its computational resources. Verification of computation in these systems, that do not assume trusted computational nodes, is a challenging task. In this paper we provide a game-theoretic analysis of an incentivized outsourcing computation system, proposed by Harz and Boman [Harz et al. 2018] (HB), at WTSC 2018 (FC Workshop), and show that the system is vulnerable to collusion and Sybil attacks, that result in incorrect solutions to be accepted by the system. We also show that malicious computational node can succeed in polluting the blockchain. We propose modifications to the system that incentivizes honest behavior, and improve the system’s correctness guarantee. We provide a high-level analysis of the modified system using our game theoretic approach, and show the effectiveness of the proposed modifications.


Outsourcing computation Verifiable distributed computation Rational adversaries Incentivized security 


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Copyright information

© International Financial Cryptography Association 2020

Authors and Affiliations

  • Mahmudun Nabi
    • 1
    Email author
  • Sepideh Avizheh
    • 1
  • Muni Venkateswarlu Kumaramangalam
    • 1
  • Reihaneh Safavi-Naini
    • 1
  1. 1.University of CalgaryCalgaryCanada

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