eprintid: 10180002 rev_number: 7 eprint_status: archive userid: 699 dir: disk0/10/18/00/02 datestamp: 2024-02-07 12:07:04 lastmod: 2024-02-07 12:07:04 status_changed: 2024-02-07 12:07:04 type: working_paper metadata_visibility: show sword_depositor: 699 creators_name: Tessone, Claudio J creators_name: Tasca, Paolo creators_name: Ianelli, Flavio title: Stochastic modelling of blockchain consensus ispublished: pub divisions: UCL divisions: B04 divisions: C05 divisions: F48 note: This version is the version of record. For information on re-use, please refer to the publisher’s terms and conditions. abstract: Blockchain and general purpose distributed ledgers are foundational technologies which bring significant innovation in the infrastructures and other underpinnings of our socio-economic systems. These P2P technologies are able to securely diffuse information within and across networks, without need for trustees or central authorities to enforce consensus. In this contribution, we propose a minimalistic stochastic model to understand the dynamics of blockchain-based consensus. By leveraging on random-walk theory, we model block propagation delay on different network topologies and provide a classification of blockchain systems in terms of two emergent properties. Firstly, we identify two performing regimes: a functional regime corresponding to an optimal system function; and a non-functional regime characterised by a congested or branched state of sub-optimal blockchains. Secondly, we discover a phase transition during the emergence of consensus and numerically investigate the corresponding critical point. Our results provide important insights into the consensus mechanism and sub-optimal states in decentralised systems. date: 2021-06-11 publisher: ArXiv official_url: https://doi.org/10.48550/arXiv.2106.06465 oa_status: green full_text_type: pub language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 2101129 lyricists_name: Tasca, Paolo lyricists_id: PTASC73 actors_name: Tasca, Paolo actors_id: PTASC73 actors_role: owner full_text_status: public place_of_pub: Ithaca, NY, USA pages: 16 citation: Tessone, Claudio J; Tasca, Paolo; Ianelli, Flavio; (2021) Stochastic modelling of blockchain consensus. ArXiv: Ithaca, NY, USA. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10180002/1/2106.06465.pdf