Game Theoretical Framework for Analyzing Blockchains Robustness

Paolo Zappalà (1, 2) , Marianna Belotti (3, 2) , Maria Potop-Butucaru (4, 5) , Stefano Secci (2)

1 Phare
2 CEDRIC - ROC - CEDRIC. Réseaux et Objets Connectés
3 CDC - Caisse des dépôts et consignations (France)
4 NPA - Networks and Performance Analysis
5 LINCS - Laboratory of Information, Network and Communication Sciences

Blockchains systems evolve in complex environments that mix classical patterns of faults (e.g crash faults, transient faults, Byzantine faults, churn) with selfish, rational or irrational behaviors typical to economical systems. In this paper we propose a game theoretical framework in order to formally characterize the robustness of blockchains systems in terms of resilience to rational deviations and immunity to Byzantine behaviors. Our framework includes necessary and sufficient conditions for checking the immunity and resilience of games and a new technique for composing games that preserves the robustness of individual games. We prove the practical interest of our formal framework by characterizing the robustness of three different protocols popular in blockchain systems: a HTLC-based payment scheme (a.k.a. Lightning Network), a side-chain protocol and a cross-chain swap protocol.

Domaines: Informatique [cs]; Calcul parallèle, distribué et partagé [cs.DC]; Réseaux et télécommunications [cs.NI]; Cryptographie et sécurité [cs.CR]

Paolo Zappalà, Marianna Belotti, Maria Potop-Butucaru, Stefano Secci. Game Theoretical Framework for Analyzing Blockchains Robustness. [Research Report] Sorbonne Université, CNRS, Laboratoire d'Informatique de Paris 6, LIP6, Paris, France. 2020. ⟨hal-02634752v1⟩