61 Search Results for "Potop-Butucaru, Maria"

Volume

OASIcs, Volume 71

International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Tokenomics 2019, May 6-7, 2019, Paris, France

Editors: Vincent Danos, Maurice Herlihy, Maria Potop-Butucaru, Julien Prat, and Sara Tucci-Piergiovanni

Volume

LIPIcs, Volume 46

19th International Conference on Principles of Distributed Systems (OPODIS 2015)

OPODIS 2015, December 14-17, 2015, Rennes, France

Editors: Emmanuelle Anceaume, Christian Cachin, and Maria Potop-Butucaru

Document
DOI: 10.4230/LIPIcs.DISC.2022.15
Dynamic Probabilistic Input Output Automata

Authors: Pierre Civit and Maria Potop-Butucaru

Published in: LIPIcs, Volume 246, 36th International Symposium on Distributed Computing (DISC 2022)

Abstract
We present probabilistic dynamic I/O automata, a framework to model dynamic probabilistic systems. Our work extends dynamic I/O Automata formalism of Attie & Lynch [Paul C. Attie and Nancy A. Lynch, 2016] to the probabilistic setting. The original dynamic I/O Automata formalism included operators for parallel composition, action hiding, action renaming, automaton creation, and behavioral sub-typing by means of trace inclusion. They can model mobility by using signature modification. They are also hierarchical: a dynamically changing system of interacting automata is itself modeled as a single automaton. Our work extends all these features to the probabilistic setting. Furthermore, we prove necessary and sufficient conditions to obtain the monotonicity of automata creation/destruction with implementation preorder. Our construction uses a novel proof technique based on homomorphism that can be of independent interest. Our work lays down the foundations for extending composable secure-emulation of Canetti et al. [Ran Canetti et al., 2007] to dynamic settings, an important tool towards the formal verification of protocols combining probabilistic distributed systems and cryptography in dynamic settings (e.g. blockchains, secure distributed computation, cybersecure distributed protocols, etc).
Cite as

Pierre Civit and Maria Potop-Butucaru. Dynamic Probabilistic Input Output Automata. In 36th International Symposium on Distributed Computing (DISC 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 246, pp. 15:1-15:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)

Copy BibTex To Clipboard

@InProceedings{civit_et_al:LIPIcs.DISC.2022.15,
  author =	{Civit, Pierre and Potop-Butucaru, Maria},
  title =	{{Dynamic Probabilistic Input Output Automata}},
  booktitle =	{36th International Symposium on Distributed Computing (DISC 2022)},
  pages =	{15:1--15:18},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-255-6},
  ISSN =	{1868-8969},
  year =	{2022},
  volume =	{246},
  editor =	{Scheideler, Christian},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2022.15},
  URN =		{urn:nbn:de:0030-drops-172064},
  doi =		{10.4230/LIPIcs.DISC.2022.15},
  annote =	{Keywords: Automata, Distributed Computing, Formal Verification, Dynamic systems}
}
Document
DOI: 10.4230/LIPIcs.DISC.2021.42
Game Theoretical Framework for Analyzing Blockchains Robustness

Authors: Paolo Zappalà, Marianna Belotti, Maria Potop-Butucaru, and Stefano Secci

Published in: LIPIcs, Volume 209, 35th International Symposium on Distributed Computing (DISC 2021)

Abstract
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 an original 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 various blockchain protocols: Bitcoin (the most popular permissionless blockchain), Tendermint (the first permissioned blockchain used by the practitioners), Lightning Network, a side-chain protocol and a cross-chain swap protocol. For each one of the studied protocols we identify upper and lower bounds with respect to their resilience and immunity (expressed as no worse payoff than the initial state) face to rational and Byzantine behaviors.
Cite as

Paolo Zappalà, Marianna Belotti, Maria Potop-Butucaru, and Stefano Secci. Game Theoretical Framework for Analyzing Blockchains Robustness. In 35th International Symposium on Distributed Computing (DISC 2021). Leibniz International Proceedings in Informatics (LIPIcs), Volume 209, pp. 42:1-42:18, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2021)

Copy BibTex To Clipboard

@InProceedings{zappala_et_al:LIPIcs.DISC.2021.42,
  author =	{Zappal\`{a}, Paolo and Belotti, Marianna and Potop-Butucaru, Maria and Secci, Stefano},
  title =	{{Game Theoretical Framework for Analyzing Blockchains Robustness}},
  booktitle =	{35th International Symposium on Distributed Computing (DISC 2021)},
  pages =	{42:1--42:18},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-210-5},
  ISSN =	{1868-8969},
  year =	{2021},
  volume =	{209},
  editor =	{Gilbert, Seth},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2021.42},
  URN =		{urn:nbn:de:0030-drops-148440},
  doi =		{10.4230/LIPIcs.DISC.2021.42},
  annote =	{Keywords: Blockchain protocols, Distributed algorithms, Game-theoretical modeling, Fault tolerance, Failure robustness}
}
Document
DOI: 10.4230/OASIcs.Tokenomics.2020.4
On Fairness in Committee-Based Blockchains

Authors: Yackolley Amoussou-Guenou, Antonella Del Pozzo, Maria Potop-Butucaru, and Sara Tucci-Piergiovanni

Published in: OASIcs, Volume 82, 2nd International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2020)

Abstract
Committee-based blockchains are among the most popular alternatives of proof-of-work based blockchains, such as Bitcoin. They provide strong consistency (no fork) under classical assumptions, and avoid using energy-consuming mechanisms to add new blocks in the blockchain. For each block, these blockchains use a committee that executes Byzantine-fault tolerant distributed consensus to decide the next block they will add in the blockchain. Unlike Bitcoin, where there is only one creator per block, in committee-based blockchain any block is cooperatively created. In order to incentivize committee members to participate in the creation of new blocks, rewarding schemes have to be designed. In this paper, we study the fairness of rewarding in committee-based blockchains and we provide necessary and sufficient conditions on the system communication under which it is possible to have a fair reward mechanism.
Cite as

Yackolley Amoussou-Guenou, Antonella Del Pozzo, Maria Potop-Butucaru, and Sara Tucci-Piergiovanni. On Fairness in Committee-Based Blockchains. In 2nd International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2020). Open Access Series in Informatics (OASIcs), Volume 82, pp. 4:1-4:15, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2021)

Copy BibTex To Clipboard

@InProceedings{amoussouguenou_et_al:OASIcs.Tokenomics.2020.4,
  author =	{Amoussou-Guenou, Yackolley and Del Pozzo, Antonella and Potop-Butucaru, Maria and Tucci-Piergiovanni, Sara},
  title =	{{On Fairness in Committee-Based Blockchains}},
  booktitle =	{2nd International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2020)},
  pages =	{4:1--4:15},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-157-3},
  ISSN =	{2190-6807},
  year =	{2021},
  volume =	{82},
  editor =	{Anceaume, Emmanuelle and Bisi\`{e}re, Christophe and Bouvard, Matthieu and Bramas, Quentin and Casamatta, Catherine},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2020.4},
  URN =		{urn:nbn:de:0030-drops-135261},
  doi =		{10.4230/OASIcs.Tokenomics.2020.4},
  annote =	{Keywords: Blockchain, Consensus, Committee, Fairness, Proof-of-Stake, Reward, Selection}
}
Document
DOI: 10.4230/LIPIcs.OPODIS.2020.12
Rational Behaviors in Committee-Based Blockchains

Authors: Yackolley Amoussou-Guenou, Bruno Biais, Maria Potop-Butucaru, and Sara Tucci-Piergiovanni

Published in: LIPIcs, Volume 184, 24th International Conference on Principles of Distributed Systems (OPODIS 2020)

Abstract
We study the rational behaviors of participants in committee-based blockchains. Committee-based blockchains rely on specific blockchain consensus that must be guaranteed in presence of rational participants. We consider a simplified blockchain consensus algorithm based on existing or proposed committee-based blockchains that encapsulate the main actions of the participants: voting for a block, and checking its validity. Knowing that those actions have costs, and achieving the consensus gives rewards to committee members, we study using game theory how strategic participants behave while trying to maximize their gains. We consider different reward schemes, and found that in each setting, there exist equilibria where blockchain consensus is guaranteed; in some settings however, there can be coordination failures hindering consensus. Moreover, we study equilibria with trembling participants, which is a novelty in the context of committee-based blockchains. Trembling participants are rational that can do unintended actions with a low probability. We found that in presence of trembling participants, there exist equilibria where blockchain consensus is guaranteed; however, when only voters are rewarded, there also exist equilibria where validity can be violated.
Cite as

Yackolley Amoussou-Guenou, Bruno Biais, Maria Potop-Butucaru, and Sara Tucci-Piergiovanni. Rational Behaviors in Committee-Based Blockchains. In 24th International Conference on Principles of Distributed Systems (OPODIS 2020). Leibniz International Proceedings in Informatics (LIPIcs), Volume 184, pp. 12:1-12:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2021)

Copy BibTex To Clipboard

@InProceedings{amoussouguenou_et_al:LIPIcs.OPODIS.2020.12,
  author =	{Amoussou-Guenou, Yackolley and Biais, Bruno and Potop-Butucaru, Maria and Tucci-Piergiovanni, Sara},
  title =	{{Rational Behaviors in Committee-Based Blockchains}},
  booktitle =	{24th International Conference on Principles of Distributed Systems (OPODIS 2020)},
  pages =	{12:1--12:16},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-176-4},
  ISSN =	{1868-8969},
  year =	{2021},
  volume =	{184},
  editor =	{Bramas, Quentin and Oshman, Rotem and Romano, Paolo},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.OPODIS.2020.12},
  URN =		{urn:nbn:de:0030-drops-134973},
  doi =		{10.4230/LIPIcs.OPODIS.2020.12},
  annote =	{Keywords: BFT Consensus, Blockchains, Game Theory}
}
Document
Brief Announcement
DOI: 10.4230/LIPIcs.DISC.2020.49
Brief Announcement: Game Theoretical Framework for Analyzing Blockchains Robustness

Authors: Paolo Zappalà, Marianna Belotti, Maria Potop-Butucaru, and Stefano Secci

Published in: LIPIcs, Volume 179, 34th International Symposium on Distributed Computing (DISC 2020)

Abstract
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.
Cite as

Paolo Zappalà, Marianna Belotti, Maria Potop-Butucaru, and Stefano Secci. Brief Announcement: Game Theoretical Framework for Analyzing Blockchains Robustness. In 34th International Symposium on Distributed Computing (DISC 2020). Leibniz International Proceedings in Informatics (LIPIcs), Volume 179, pp. 49:1-49:3, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{zappala_et_al:LIPIcs.DISC.2020.49,
  author =	{Zappal\`{a}, Paolo and Belotti, Marianna and Potop-Butucaru, Maria and Secci, Stefano},
  title =	{{Brief Announcement: Game Theoretical Framework for Analyzing Blockchains Robustness}},
  booktitle =	{34th International Symposium on Distributed Computing (DISC 2020)},
  pages =	{49:1--49:3},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-168-9},
  ISSN =	{1868-8969},
  year =	{2020},
  volume =	{179},
  editor =	{Attiya, Hagit},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.DISC.2020.49},
  URN =		{urn:nbn:de:0030-drops-131275},
  doi =		{10.4230/LIPIcs.DISC.2020.49},
  annote =	{Keywords: Blockchains, Game Theory, Byzantine-Altruistic-Rational behaviours}
}
Document
Complete Volume
DOI: 10.4230/OASIcs.Tokenomics.2019
OASIcs, Vol. 71, Tokenomics 2019, Complete Volume

Authors: Vincent Danos, Maurice Herlihy, Maria Potop-Butucaru, Julien Prat, and Sara Tucci-Piergiovanni

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
OASIcs, Vol. 71, Tokenomics 2019, Complete Volume
Cite as

International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, pp. 1-192, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@Proceedings{danos_et_al:OASIcs.Tokenomics.2019,
  title =	{{OASIcs, Vol. 71, Tokenomics 2019, Complete Volume}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{1--192},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019},
  URN =		{urn:nbn:de:0030-drops-119634},
  doi =		{10.4230/OASIcs.Tokenomics.2019},
  annote =	{Keywords: OASIcs, Vol. 71, Tokenomics 2019, Complete Volume}
}
Document
Front Matter
DOI: 10.4230/OASIcs.Tokenomics.2019.0
Front Matter, Table of Contents, Preface, Conference Organization

Authors: Vincent Danos, Maurice Herlihy, Maria Potop-Butucaru, Julien Prat, and Sara Tucci-Piergiovanni

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
Front Matter, Table of Contents, Preface, Conference Organization
Cite as

International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, pp. 0:i-0:xii, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{danos_et_al:OASIcs.Tokenomics.2019.0,
  author =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  title =	{{Front Matter, Table of Contents, Preface, Conference Organization}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{0:i--0:xii},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019.0},
  URN =		{urn:nbn:de:0030-drops-119640},
  doi =		{10.4230/OASIcs.Tokenomics.2019.0},
  annote =	{Keywords: Front Matter, Table of Contents, Preface, Conference Organization}
}
Document
Keynote Lecture
DOI: 10.4230/OASIcs.Tokenomics.2019.1
Demystifying Blockchains: Decentralized and Fault-Tolerant Storage for the Future of Big Data? (Keynote Lecture)

Authors: Amr El Abbadi

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
Bitcoin is a successful and interesting example of a global scale peer-to-peer cryptocurrency that integrates many techniques and protocols from cryptography, distributed systems, and databases. The main underlying data structure is blockchain, a scalable fully replicated structure that is shared among all participants and guarantees a consistent view of all user transactions by all participants in the cryptocurrency system. The novel aspect of Blockchain is that historical data about all transactions is maintained in the absence of any central authority. This property of Blockchain has given rise to the possibility that future applications will transition from centralized databases to a fully decentralized storage based on blockchains. In this talk, we start by developing an understanding of the basic protocols used in blockchain, and elaborate on their main advantages and limitations. To overcome these limitations, we will explore some of the challenges of managing large scale fully replicated ledgers in the context of achieving large scale consensus. Finally, we ponder over recent efforts to use blockchains in diverse applications.
Cite as

Amr El Abbadi. Demystifying Blockchains: Decentralized and Fault-Tolerant Storage for the Future of Big Data? (Keynote Lecture). In International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, p. 1:1, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{abbadi:OASIcs.Tokenomics.2019.1,
  author =	{Abbadi, Amr El},
  title =	{{Demystifying Blockchains: Decentralized and Fault-Tolerant Storage for the Future of Big Data?}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{1:1--1:1},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019.1},
  URN =		{urn:nbn:de:0030-drops-119658},
  doi =		{10.4230/OASIcs.Tokenomics.2019.1},
  annote =	{Keywords: distributed algorithms for databases, distributed storage, blockchains}
}
Document
Keynote Lecture
DOI: 10.4230/OASIcs.Tokenomics.2019.2
Flexible BFT: Separating BFT Protocol Design from the Fault Model (Keynote Lecture)

Authors: Dahlia Malkhi

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
Byzantine Fault Tolerant (BFT) protocols designed for building replicated services collapse if deployed under settings that differ from the fault model they are designed for. For example, in a partial-synchrony model, a known lower bound for BFT is 1/3. Optimal-resilience solutions completely break if the fraction of Byzantine faults exceeds 1/3. The only way we know to achieve > 1/3 resilience is by assuming synchrony, but this requires the protocol to be designed with that assumption. Flexible BFT is a new approach to BFT protocol design that separates between the fault model and the solution. Clients in Flexible BFT specify (i) the adversarial threshold they need to tolerate, and (ii) whether they believe in synchrony (and the presumed bound on transmission delays). We present a Flexible BFT solution that simultaneously supports different clients, who differ simply by the number of messages and/or time the clients are willing to wait for. At an even finer grain, Flexible BFT supports under the same solution high-value and low-value transactions, each tolerating a different threat model.
Cite as

Dahlia Malkhi. Flexible BFT: Separating BFT Protocol Design from the Fault Model (Keynote Lecture). In International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, p. 2:1, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{malkhi:OASIcs.Tokenomics.2019.2,
  author =	{Malkhi, Dahlia},
  title =	{{Flexible BFT: Separating BFT Protocol Design from the Fault Model}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{2:1--2:1},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019.2},
  URN =		{urn:nbn:de:0030-drops-119660},
  doi =		{10.4230/OASIcs.Tokenomics.2019.2},
  annote =	{Keywords: Byzantine fault-tolerance, blockchains}
}
Document
DOI: 10.4230/OASIcs.Tokenomics.2019.3
A Puff of Steem: Security Analysis of Decentralized Content Curation

Authors: Aggelos Kiayias, Benjamin Livshits, Andrés Monteoliva Mosteiro, and Orfeas Stefanos Thyfronitis Litos

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
Decentralized content curation is the process through which uploaded posts are ranked and filtered based exclusively on users' feedback. Platforms such as the blockchain-based Steemit employ this type of curation while providing monetary incentives to promote the visibility of high quality posts according to the perception of the participants. Despite the wide adoption of the platform very little is known regarding its performance and resilience characteristics. In this work, we provide a formal model for decentralized content curation that identifies salient complexity and game-theoretic measures of performance and resilience to selfish participants. Armed with our model, we provide a first analysis of Steemit identifying the conditions under which the system can be expected to correctly converge to curation while we demonstrate its susceptibility to selfish participant behaviour. We validate our theoretical results with system simulations in various scenarios.
Cite as

Aggelos Kiayias, Benjamin Livshits, Andrés Monteoliva Mosteiro, and Orfeas Stefanos Thyfronitis Litos. A Puff of Steem: Security Analysis of Decentralized Content Curation. In International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, pp. 3:1-3:21, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{kiayias_et_al:OASIcs.Tokenomics.2019.3,
  author =	{Kiayias, Aggelos and Livshits, Benjamin and Monteoliva Mosteiro, Andr\'{e}s and Thyfronitis Litos, Orfeas Stefanos},
  title =	{{A Puff of Steem: Security Analysis of Decentralized Content Curation}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{3:1--3:21},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019.3},
  URN =		{urn:nbn:de:0030-drops-119675},
  doi =		{10.4230/OASIcs.Tokenomics.2019.3},
  annote =	{Keywords: blockchain, content curation, decentralized, voting}
}
Document
DOI: 10.4230/OASIcs.Tokenomics.2019.4
An Empirical Study of Speculative Concurrency in Ethereum Smart Contracts

Authors: Vikram Saraph and Maurice Herlihy

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
We use historical data to estimate the potential benefit of speculative techniques for executing Ethereum smart contracts in parallel. We replay transaction traces of sampled blocks from the Ethereum blockchain over time, using a simple speculative execution engine. In this engine, miners attempt to execute all transactions in a block in parallel, rolling back those that cause data conflicts. Aborted transactions are then executed sequentially. Validators execute the same schedule as miners. We find that our speculative technique yields estimated speed-ups starting at about 8-fold in 2016, declining to about 2-fold at the end of 2017, where speed-up is measured using either gas costs or instruction counts. We also observe that a small set of contracts are responsible for many data conflicts resulting from speculative concurrent execution.
Cite as

Vikram Saraph and Maurice Herlihy. An Empirical Study of Speculative Concurrency in Ethereum Smart Contracts. In International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, pp. 4:1-4:15, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{saraph_et_al:OASIcs.Tokenomics.2019.4,
  author =	{Saraph, Vikram and Herlihy, Maurice},
  title =	{{An Empirical Study of Speculative Concurrency in Ethereum Smart Contracts}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{4:1--4:15},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019.4},
  URN =		{urn:nbn:de:0030-drops-119684},
  doi =		{10.4230/OASIcs.Tokenomics.2019.4},
  annote =	{Keywords: Blockchains, Smart Contracts}
}
Document
DOI: 10.4230/OASIcs.Tokenomics.2019.5
Atomic Appends: Selling Cars and Coordinating Armies with Multiple Distributed Ledgers

Authors: Antonio Fernández Anta, Chryssis Georgiou, and Nicolas Nicolaou

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
The various applications using Distributed Ledger Technologies (DLT) or blockchains, have led to the introduction of a new "marketplace" where multiple types of digital assets may be exchanged. As each blockchain is designed to support specific types of assets and transactions, and no blockchain will prevail, the need to perform interblockchain transactions is already pressing. In this work we examine the fundamental problem of interoperable and interconnected blockchains. In particular, we begin by introducing the Multi-Distributed Ledger Objects (MDLO), which is the result of aggregating multiple Distributed Ledger Objects - DLO (a DLO is a formalization of the blockchain) and that supports append and get operations of records (e.g., transactions) in them from multiple clients concurrently. Next we define the AtomicAppends problem, which emerges when the exchange of digital assets between multiple clients may involve appending records in more than one DLO. Specifically, AtomicAppend requires that either all records will be appended on the involved DLOs or none. We examine the solvability of this problem assuming rational and risk-averse clients that may fail by crashing, and under different client utility and append models, timing models, and client failure scenarios. We show that for some cases the existence of an intermediary is necessary for the problem solution. We propose the implementation of such intermediary over a specialized blockchain, we term Smart DLO (SDLO), and we show how this can be used to solve the AtomicAppends problem even in an asynchronous, client competitive environment, where all the clients may crash.
Cite as

Antonio Fernández Anta, Chryssis Georgiou, and Nicolas Nicolaou. Atomic Appends: Selling Cars and Coordinating Armies with Multiple Distributed Ledgers. In International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, pp. 5:1-5:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{fernandezanta_et_al:OASIcs.Tokenomics.2019.5,
  author =	{Fern\'{a}ndez Anta, Antonio and Georgiou, Chryssis and Nicolaou, Nicolas},
  title =	{{Atomic Appends: Selling Cars and Coordinating Armies with Multiple Distributed Ledgers}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{5:1--5:16},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019.5},
  URN =		{urn:nbn:de:0030-drops-119695},
  doi =		{10.4230/OASIcs.Tokenomics.2019.5},
  annote =	{Keywords: DLO, Interoperability, Atomic Appends, Rational Clients, Fault-tolerance}
}
Document
DOI: 10.4230/OASIcs.Tokenomics.2019.6
A Smart Contract Oracle for Approximating Real-World, Real Number Values

Authors: William George and Clément Lesaege

Published in: OASIcs, Volume 71, International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)

Abstract
A key challenge of smart contract systems is the fact that many useful contracts require access to information that does not natively live on the blockchain. While miners can verify the value of a hash or the validity of a digital signature, they cannot determine who won an election, whether there is a flood in Paris, or even what is the price of ether in US dollars, even though this information might be necessary to execute prediction market, insurance, or financial contracts respectively. A number of promising projects and research developments have provided a better understanding of how one might construct a decentralized, binary oracle - namely an oracle that can respond by one of two possibilities, typically "yes" or "no", even while not requiring the interaction of a trusted third party. In this work, we extend these ideas to construct a general-purpose, decentralized oracle that can estimate the value of a real-world quantity that is in a dense totally ordered set, such as R. In particular, this proposal can be used to estimate real number valued quantities, such as required for a price oracle. We will establish a number of desirable properties about this proposal. Particularly, we will see that the precision of the output is tunable to users' needs.
Cite as

William George and Clément Lesaege. A Smart Contract Oracle for Approximating Real-World, Real Number Values. In International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019). Open Access Series in Informatics (OASIcs), Volume 71, pp. 6:1-6:15, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)

Copy BibTex To Clipboard

@InProceedings{george_et_al:OASIcs.Tokenomics.2019.6,
  author =	{George, William and Lesaege, Cl\'{e}ment},
  title =	{{A Smart Contract Oracle for Approximating Real-World, Real Number Values}},
  booktitle =	{International Conference on Blockchain Economics, Security and Protocols (Tokenomics 2019)},
  pages =	{6:1--6:15},
  series =	{Open Access Series in Informatics (OASIcs)},
  ISBN =	{978-3-95977-108-5},
  ISSN =	{2190-6807},
  year =	{2020},
  volume =	{71},
  editor =	{Danos, Vincent and Herlihy, Maurice and Potop-Butucaru, Maria and Prat, Julien and Tucci-Piergiovanni, Sara},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/OASIcs.Tokenomics.2019.6},
  URN =		{urn:nbn:de:0030-drops-119705},
  doi =		{10.4230/OASIcs.Tokenomics.2019.6},
  annote =	{Keywords: price oracle, Ethereum, blockchain}
}
  • Refine by Author
  • 10 Potop-Butucaru, Maria
  • 5 Tucci-Piergiovanni, Sara
  • 4 Herlihy, Maurice
  • 3 Amoussou-Guenou, Yackolley
  • 2 Anceaume, Emmanuelle
  • Show More...

  • Refine by Classification
  • 4 Security and privacy → Distributed systems security
  • 3 Computer systems organization → Dependable and fault-tolerant systems and networks
  • 3 Computing methodologies → Distributed algorithms
  • 2 Applied computing → Economics
  • 2 Networks
  • Show More...

  • Refine by Keyword
  • 5 Ethereum
  • 4 Consensus
  • 3 Blockchain
  • 3 Blockchains
  • 3 Fairness
  • Show More...

  • Refine by Type
  • 59 document
  • 2 volume

  • Refine by Publication Year
  • 39 2016
  • 17 2020
  • 3 2021
  • 1 2019
  • 1 2022

Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail
© 2023-2024 Schloss Dagstuhl – LZI GmbH Imprint Privacy Contact