Be Selfish and Avoid Dilemmas: Fork After Withholding (FAW) Attacks on Bitcoin

  title={Be Selfish and Avoid Dilemmas: Fork After Withholding (FAW) Attacks on Bitcoin},
  author={Yujin Kwon and Dohyun Kim and Yunmok Son and Eugene Y. Vasserman and Yongdae Kim},
  journal={Proceedings of the 2017 ACM SIGSAC Conference on Computer and Communications Security},
  • Yujin KwonDohyun Kim Yongdae Kim
  • Published 31 August 2017
  • Computer Science
  • Proceedings of the 2017 ACM SIGSAC Conference on Computer and Communications Security
In the Bitcoin system, participants are rewarded for solving cryptographic puzzles. In order to receive more consistent rewards over time, some participants organize mining pools and split the rewards from the pool in proportion to each participant's contribution. However, several attacks threaten the ability to participate in pools. The block withholding (BWH) attack makes the pool reward system unfair by letting malicious participants receive unearned wages while only pretending to contribute… 

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