The Synchronization Power (Consensus Number) of Access-Control Objects: the Case of AllowList and DenyList

Authors Davide Frey, Mathieu Gestin, Michel Raynal

Thumbnail PDF


  • Filesize: 0.85 MB
  • 23 pages

Document Identifiers

Author Details

Davide Frey
  • Inria, IRISA, CNRS, Université de Rennes, France
Mathieu Gestin
  • Inria, IRISA, CNRS, Université de Rennes, France
Michel Raynal
  • IRISA, Inria, CNRS, Université de Rennes, France


We wish to thank the anonymous reviewers for their insightful comments and remarks that led to significant improvements to our paper.

Cite AsGet BibTex

Davide Frey, Mathieu Gestin, and Michel Raynal. The Synchronization Power (Consensus Number) of Access-Control Objects: the Case of AllowList and DenyList. In 37th International Symposium on Distributed Computing (DISC 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 281, pp. 21:1-21:23, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)


This article studies the synchronization power of AllowList and DenyList objects under the lens provided by Herlihy’s consensus hierarchy. It specifies AllowList and DenyList as distributed objects and shows that, while they can both be seen as specializations of a more general object type, they inherently have different synchronization power. While the AllowList object does not require synchronization between participating processes, a DenyList object requires processes to reach consensus on a specific set of processes. These results are then applied to a more global analysis of anonymity-preserving systems that use AllowList and DenyList objects. First, a blind-signature-based e-voting is presented. Second, DenyList and AllowList objects are used to determine the consensus number of a specific decentralized key management system. Third, an anonymous money transfer algorithm using the association of AllowList and DenyList objects is presented. Finally, this analysis is used to study the properties of these application, and to highlight efficiency gains that they can achieve in message passing environment.

Subject Classification

ACM Subject Classification
  • Theory of computation → Distributed computing models
  • Security and privacy → Access control
  • Security and privacy → Pseudonymity, anonymity and untraceability
  • Access control
  • AllowList/DenyList
  • Blockchain
  • Consensus number
  • Distributed objects
  • Modularity
  • Privacy
  • Synchronization power


  • Access Statistics
  • Total Accesses (updated on a weekly basis)
    PDF Downloads


  1. Ethereum name service documentation. online - - accessed 23/11/2022.
  2. Yehuda Afek, Hagit Attiya, Danny Dolev, Eli Gafni, Michael Merritt, and Nir Shavit. Atomic snapshots of shared memory. JACM, 40(4):873-890, September 1993. URL:
  3. Orestis Alpos, Christian Cachin, Giorgia Azzurra Marson, and Luca Zanolini. On the synchronization power of token smart contracts. In 41st IEEE ICDCS, pages 640-651, 2021. URL:
  4. Pierre-Louis Aublin, Sonia Ben Mokhtar, and Vivien Quéma. Rbft: Redundant byzantine fault tolerance. In IEEE 33rd International Conference on Distributed Computing Systems, pages 297-306, 2013. URL:
  5. Alex Auvolat, Davide Frey, Michel Raynal, and François Taïani. Money Transfer Made Simple: a Specification, a Generic Algorithm, and its Proof. Bulletin European Association for Theoretical Computer Science, 132, October 2020. Google Scholar
  6. Olivier Baudron, Pierre-Alain Fouque, David Pointcheval, Jacques Stern, and Guillaume Poupard. Practical multi-candidate election system. In PODC, pages 274-283, 2001. URL:
  7. Eli Ben Sasson, Alessandro Chiesa, Christina Garman, Matthew Green, Ian Miers, Eran Tromer, and Madars Virza. Zerocash: Decentralized anonymous payments from bitcoin. In 2014 IEEE Symposium on Security and Privacy, pages 459-474, May 2014. URL:
  8. Daniel Benarroch, Matteo Campanelli, Dario Fiore, Kobi Gurkan, and Dimitris Kolonelos. Zero-knowledge proofs for set membership: Efficient, succinct, modular. In Financial Cryptography and Data Security. Springer Berlin Heidelberg, 2021. Google Scholar
  9. Gabriel Bracha. Asynchronous byzantine agreement protocols. Information and Computation, 75(2):130-143, 1987. URL:
  10. Miguel Castro and Barbara Liskov. Practical byzantine fault tolerance. In OSDI '99, pages 173-186, 1999. Google Scholar
  11. Miguel Castro and Barbara Liskov. Proactive recovery in a Byzantine-Fault-Tolerant system. In OSDI 2000, October 2000. URL:
  12. Keren Censor-Hillel, Erez Petrank, and Shahar Timnat. Help! In PODC '15, pages 241-250, 2015. URL:
  13. David Chaum. Blind signatures for untraceable payments. In Advances in Cryptology, pages 199-203, 1983. Google Scholar
  14. Michael R. Clarkson, Stephen Chong, and Andrew C. Myers. Civitas: Toward a secure voting system. IEEE SSP, pages 354-368, 2008. Google Scholar
  15. Ronald Cramer, Rosario Gennaro, and Berry Schoenmakers. A secure and optimally efficient multi-authority election scheme. In EUROCRYPT '97, pages 103-118, 1997. Google Scholar
  16. Gaby G. Dagher, Praneeth Babu Marella, Matea Milojkovic, and Jordan Mohler. Broncovote: Secure voting system using ethereum’s blockchain. In ICISSP, 2018. Google Scholar
  17. Michael J. Fischer, Nancy A. Lynch, and Michael S. Paterson. Impossibility of distributed consensus with one faulty process. J. ACM, 32(2):374-382, April 1985. URL:
  18. Sovrin Foundation. Sovrin: A protocol and token for self-sovereign identity and decentralized trust. Technical report, Sovrin Foundation, 2018. Google Scholar
  19. Davide Frey, Mathieu Gestin, and Michel Raynal. The synchronization power (consensus number) of access-control objects: The case of allowlist and denylist, 2023. URL:
  20. Atsushi Fujioka, Tatsuaki Okamoto, and Kazuo Ohta. A practical secret voting scheme for large scale elections. In AUSCRYPT '92, pages 244-251, 1993. Google Scholar
  21. Jyoti Grover. Security of vehicular ad hoc networks using blockchain: A comprehensive review. Vehicular Communications, 34:100458, 2022. URL:
  22. Rachid Guerraoui, Petr Kuznetsov, Matteo Monti, Matej Pavlovič, and Dragos-Adrian Seredinschi. The consensus number of a cryptocurrency. In PODC '19, pages 307-316, 2019. URL:
  23. Maurice Herlihy. Wait-free synchronization. ACM Trans. Program. Lang. Syst., 13(1):124-149, January 1991. URL:
  24. Maurice P Herlihy and Jeannette M Wing. Linearizability: A correctness condition for concurrent objects. ACM Transactions on Programming Languages and Systems, 12(3):463-492, 1990. Google Scholar
  25. Markus Jakobsson, Ari Juels, and Ronald L. Rivest. Making mix nets robust for electronic voting by randomized partial checking. In 11th USENIX Security Symposium, August 2002. URL:
  26. Ari Juels, Dario Catalano, and Markus Jakobsson. Coercion-resistant electronic elections. In WPES, pages 61-70, 2005. URL:
  27. Harry A. Kalodner, Miles Carlsten, Paul Ellenbogen, Joseph Bonneau, and Arvind Narayanan. An empirical study of namecoin and lessons for decentralized namespace design. In Workshop on the Economics of Information Security, 2015. Google Scholar
  28. Leslie Lamport. Time, clocks and the ordering of events in a distributed system. Communications of the ACM 21, (7), 558-565, July 1978. URL:
  29. Leslie Lamport. The part-time parliament. In ACM TOCS, pages 133-169, 1998. URL:
  30. Ming K. Lim, Yan Li, Chao Wang, and Ming-Lang Tseng. A literature review of blockchain technology applications in supply chains: A comprehensive analysis of themes, methodologies and industries. Computers and Industrial Engineering, 154:107133, 2021. URL:
  31. Nitin Naik and Paul Jenkins. uport open-source identity management system: An assessment of self-sovereign identity and user-centric data platform built on blockchain. In IEEE International Symposium on Systems Engineering (ISSE), pages 1-7, 2020. URL:
  32. Miyako Ohkubo, Fumiaki Miura, Masayuki Abe, Atsushi Fujioka, and Tatsuaki Okamoto. An improvement on a practical secret voting scheme. In Information Security, pages 225-234, 1999. Google Scholar
  33. Torben Pryds Pedersen. Non-interactive and information-theoretic secure verifiable secret sharing. In Advances in Cryptology - CRYPTO '91, pages 129-140, 1992. Google Scholar
  34. Andreas Pfitzmann and Marit Hansen. Anonymity, unlinkability, undetectability, unobservability, pseudonymity, and identity management–a consolidated proposal for terminology. Version v0, 31, January 2007. Google Scholar
  35. Nicolas van Saberhagen. Cryptonote v 2.0, October 2013. Google Scholar
Questions / Remarks / Feedback

Feedback for Dagstuhl Publishing

Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail