Peer-to-Peer Permissionless Consensus via Reputation

  • Francisco Sant’Anna UERJ
  • Fabio Bosisio UERJ
  • Lucas Pires UERJ


Public Internet forums suffer from excess and abuse, such as SPAM and fake news. Centralized platforms employ filtering and anti-abuse policies, but imply full trust from users. We propose a permissionless Sybil-resistant peer-to-peer protocol for content sharing. Our main contribution is a reputation system that moderates content and, at the same time, delivers network consensus. We can trace a parallel with Bitcoin as follows: consolidated posts create reputation (vs proof-of-work), likes and dislikes transfer reputation (vs transactions), and aggregate reputation determines consensus (vs longest chain). The reputation mechanism depends exclusively on the human authoring ability (proof-of-authoring), which is slow and scarce, thus suitable to establish consensus.


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SANT’ANNA, Francisco; BOSISIO, Fabio; PIRES, Lucas. Peer-to-Peer Permissionless Consensus via Reputation. In: SIMPÓSIO BRASILEIRO DE SEGURANÇA DA INFORMAÇÃO E DE SISTEMAS COMPUTACIONAIS (SBSEG), 23. , 2023, Juiz de Fora/MG. Anais [...]. Porto Alegre: Sociedade Brasileira de Computação, 2023 . p. 470-483. DOI: