Les grands écrivains français par dissertation. XIXe siécle : Tome I, Vers le Romantisme. Précurseurs et Doctrines Tome II, Poésie et Theatre romantiques Tome III, Romanciers romantiques Tome IV, Vers le roman réaliste et naturaliste Tome VII, La Poésie symboliste . : Verlaine et Rimbaud Tome VIII, La Poésie symboliste . : Les orfèvres . : Mallarmé, Samain, Henri de Régnier / Pierre Michel

• Record Nr.: UNISOBE600200048140
• Autore: Michel, Pierre
• Pubbl/distr/stampa: Paris : Les Éditions Foucher, 1963; 1965; 1966; 1968
• Descrizione fisica: 6 v. : 16 cm
• Collana: Expliquez-moi ... : Littérature
• Lingua di pubblicazione: Francese
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Note generali: (cv)

Een beeld in technicolor (2nd Edition)

• Record Nr.: UNINA9910746597803321
• Pubbl/distr/stampa: Radboud University Press
• Lingua di pubblicazione: Inglese
• Formato: Materiale a stampa
• Livello bibliografico: Monografia

Financial cryptography and data security : 25th International Conference, FC 2021, Virtual event, March 1-5, 2021, Revised selected papers. Part II / / edited by Nikita Borisov and Claudia Diaz

• Record Nr.: UNISA996464531903316
• Pubbl/distr/stampa: Berlin, Germany : , : Springer, , [2021]; ©2021
• ISBN: 3-662-64331-6
• Descrizione fisica: 1 online resource (611 pages)
• Collana: Lecture Notes in Computer Science ; ; v.12675
• Disciplina: 005.824
• Soggetti: Data encryption (Computer science); User-centered system design; Computer security
• Lingua di pubblicazione: Inglese
• Formato: Materiale a stampa
• Livello bibliografico: Monografia
• Note generali: Includes index.
• Nota di contenuto: Intro -- Preface -- Organization -- Contents - Part II -- Contents - Part I -- Blockchain Protocols -- SoK: Communication Across Distributed Ledgers -- 1 Introduction -- 2 The Cross-Chain Communication Problem -- 2.1 Historical Background: Distributed Databases -- 2.2 Distributed Ledger Model -- 2.3 Cross-Chain Communication System Model -- 2.4 Formalization of Correct Cross-Chain Communication -- 2.5 The Generic CCC Protocol -- 3 Impossibility of CCC Without a Trusted Third Party -- 3.1 What Is a Trusted Third Party? -- 3.2 Relating CCC to Fair Exchange -- 3.3 ; Incentives and Rational CCC -- 4 The CCC Design Framework -- 4.1 (Pre-)Commit Phase -- 4.2 Verification Phase -- 4.3 Abort Phase -- 5 Classification of Existing CCC Protocols -- 5.1 Exchange Protocols -- 5.2 Migration Protocols -- 5.3 Insights and General Observations -- 6 CCC Challenges and Outlook -- 6.1 Heterogeneous Models and Parameters Across Chains -- 6.2 Heterogeneous Cryptographic Primitives Across Chains -- 6.3 Collateralization and Exchange Rates -- 6.4 Lack of Formal Security Analysis -- 6.5 Lack of Formal Privacy Analysis -- 6.6 Upcoming Industrial and Research CCC Trends -- 7 Concluding Remarks -- A Fair Exchange Using CCC -- References -- Reparo: Publicly Verifiable Layer to Repair Blockchains -- 1 Introduction -- 1.1 Existing Solutions and Their Limitations -- 1.2 Our Contributions -- 2 A Primer on Ethereum -- 2.1 Ethereum Ledger -- 3 Repairability in Ethereum -- 3.1 Repairing Ethereum Using Reparo -- 3.2 Discussion -- 4 Experiments in Ethereum -- 4.1 Special Transactions: repairTx, voteTx -- 4.2 Performing Repairs -- 5 Conclusion and Future Work -- A Prominent Bugs -- References -- Short Paper: Debt Representation in UTXO Blockchains -- 1 Introduction -- 2 Transactions in the UTXO Model -- 3 Debt-Enabling UTXO Blockchain -- 3.1 Debt Transactions.; 3.2 Outstanding Debt Transactions and Debt Pools -- 4 Prototype -- 4.1 System Architecture -- 4.2 Implementation -- 5 Conclusion -- References -- Instant Block Confirmation in the Sleepy Model -- 1 Introduction -- 2 Technical Roadmap -- 2.1 Starting Point: Algorand -- 2.2 Selecting a Committee -- 2.3 Consensus with Different Committees -- 2.4 Summary of Challenges and Theorem Statement -- 3 Related Work -- 3.1 Comparison of Confirmation Times and Communication Complexity -- 4 Definitions -- 4.1 Blockchain Execution Model -- 4.2 Tools -- 4.3 Other Notation -- 5 The Blockchain Protocol -- 5.1 Committee Selection -- 5.2 Binary Byzantine Agreement -- 5.3 Block Proposal -- 5.4 Putting It All Together -- References -- Blockchain CAP Theorem Allows User-Dependent Adaptivity and Finality -- 1 Introduction -- 1.1 Our Contributions -- 2 Related Work -- 3 Security Model -- 4 Protocol Description -- 5 Main Result -- 6 Conclusion -- A Algorand BA is a Checkpointing Protocol -- References -- PoSAT: Proof-of-Work Availability and Unpredictability, Without the Work -- 1 Introduction -- 1.1 Dynamic Availability -- 1.2 Static vs Dynamic Adversary -- 1.3 PoSAT Achieves PoW Dynamic Availability -- 1.4 PoSAT Has PoW Unpredictability -- 1.5 Related Work -- 1.6 Outline -- 2 Protocol -- 2.1 Primitives -- 2.2 Protocol Description -- 3 Model -- 4 Security Analysis -- 4.1 Main Security Result -- 4.2 Step 1: Mining Lag of Newly Joined Nodes -- 4.3 Step 2: Simulating a Static System -- 4.4 Step 3: Upgrading the Adversary -- 4.5 Step 4: Growth Rate of the Adversarial Tree -- 4.6 Step 5: Existence of Nakamoto Blocks -- 4.7 Step 6: Putting Back All Together -- 5 Discussion -- References -- Payment Channels -- Post-Quantum Adaptor Signature for Privacy-Preserving Off-Chain Payments -- 1 Introduction -- 2 Preliminaries -- 2.1 Adaptor Signatures (AS).; 2.2 Elliptic Curves and Isogenies -- 2.3 Security Assumptions: GAIP and MT-GAIP -- 3 CSI-FiSh -- 3.1 Zero-Knowledge Proof for Group Actions -- 4 IAS: An Adaptor Signature from Isogenies -- 4.1 Our Construction -- 5 Performance Evaluation -- 5.1 Evaluation Results -- 5.2 Comparison with LAS -- 6 Building Payment-Channel Networks from IAS -- 7 Conclusion -- References -- FPPW: A Fair and Privacy Preserving Watchtower for Bitcoin -- 1 Introduction -- 1.1 Our Contribution -- 2 Preliminaries and Notations -- 2.1 Preliminaries -- 2.2 Notations -- 3 FPPW Overview -- 3.1 System Model -- 3.2 FPPW Overview -- 3.3 Watchtower Service Properties -- 4 FPPW Channel -- ; 4.1 FPPW Channel Establishment -- 4.2 FPPW Channel Update -- 4.3 FPPW Channel Closure -- 4.4 FPPW Watchtower Abort -- 5 Security Analysis -- 6 Fee Handling -- References -- Congestion Attacks in Payment Channel Networks -- 1 Introduction -- 2 Background on the Lightning Network -- 3 Lightning Network Analysis -- 3.1 Default Parameter Values -- 3.2 Network Statistics -- 4 Attacking the Entire Network -- 4.1 Evaluation -- 5 Attacking Hubs - Attack on a Single Node -- 5.1 Evaluation -- 6 Mitigation Techniques -- 7 Related Work -- 8 Conclusions and Future Work -- References -- Payment Trees: Low Collateral Payments for Payment Channel Networks -- 1 Introduction -- 2 Background -- 3 The Channel Closure Attack on AMCU -- 4 Protocol Overview -- 5 Transactions -- 6 Our Payment Tree Construction -- 7 Collateral Efficiency and Security Analysis -- 8 Conclusion -- References -- Brick: Asynchronous Incentive-Compatible Payment Channels -- 1 Introduction -- 2 Protocol Overview -- 2.1 System Model -- 2.2 Brick Overview -- 2.3 Reward Allocation and Collateral -- 2.4 Protocol Goals -- 3 Brick Design -- 3.1 Architecture -- 3.2 Incentivizing Honest Behavior -- 4 Brick Analysis -- 5 Evaluation of Brick -- 6 Related Work.; 7 Conclusion, Limitations and Extensions -- References -- Mining -- Ignore the Extra Zeroes: Variance-Optimal Mining Pools -- 1 Introduction -- 1.1 Our Contributions -- 1.2 Related Work -- 2 Preliminaries -- 2.1 Model of Miners -- 2.2 Reward Sharing Schemes -- 2.3 Message-Independence and Symmetrization -- 2.4 A Reward-Sharing Scheme as a Hashrate Estimator -- 2.5 When t is Random -- 3 Warm-Up: Maximizing Likelihood -- 4 Main Results: Variance-Optimality -- 4.1 Single-Class Shares Are Optimal -- 4.2 PPS is Variance-Optimal -- 4.3 Variance-Optimality of PPLNS -- 4.4 Relaxing the Constraints -- 5 Conclusions and Discussion -- References -- HaPPY-Mine: Designing a Mining Reward Function -- 1 Introduction -- 1.1 Main Contributions -- 2 Background -- 3 Hashrate-Pegged Block Reward -- 4 HaPPY-Mine Equilibrium Analysis -- 4.1 Examples with Diverse Cost Scenarios -- 4.2 General Analysis of HaPPY-Mine -- 5 Impact of Attacks and Currency on Equilibria -- 6 Discussion -- 7 Related Work -- References -- Selfish Mining Attacks Exacerbated by Elastic Hash Supply -- 1 Introduction -- 2 Empirical Findings -- 3 Model with Elastic Hash Supply -- References -- Scaling Blockchains -- Fraud and Data Availability Proofs: Detecting Invalid Blocks in Light Clients -- 1 Introduction and Motivation -- 2 Background -- 3 Assumptions and Threat Model -- 3.1 Blockchain Model -- 3.2 Participants and Threat Model -- 4 Fraud Proofs -- 4.1 State Root and Execution Trace Construction -- 4.2 Data Root and Periods -- 4.3 Proof of Invalid State Transition -- 5 Data Availability Proofs -- 5.1 2D Reed-Solomon Encoded Merkle Tree Construction -- 5.2 Random Sampling and Network Block Recovery -- 5.3 Fraud Proofs of Incorrectly Generated Extended Data -- 5.4 Security Probability Analysis -- 6 Performance and Implementation. -- 7 Related Work -- 7.1 SParse FrAud pRotection (SPAR).; 8 Conclusion -- References -- ACeD: Scalable Data Availability Oracle -- 1 Introduction -- 2 System and Security Model -- 2.1 Network Model and Assumptions -- 2.2 Oracle Model -- 3 Technical Description of ACeD -- 3.1 Coded Interleaving Tree -- 3.2 Dispersal Protocol -- 3.3 Retrieval Protocol and Block Decoding -- 3.4 Protocol Summary -- 4 Performance Guarantees of ACeD -- 4.1 Security -- 4.2 Efficiency -- 5 Algorithm to System Design and Implementation -- 6 Evaluation -- 7 Conclusion and Discussion -- References -- Efficient State Management in Distributed Ledgers -- 1 Introduction -- 2 A UTxO Model -- 3 Transaction Optimization -- 3.1 Transaction Logical ; Operators - Ledger State Algebra -- 3.2 A Transaction Optimization Framework -- 3.3 Transaction Optimization Techniques -- 3.4 The Transaction Optimization Problem -- 4 State Efficiency in Bitcoin -- 4.1 A State Efficient Bitcoin -- 5 Conclusion -- References -- Fast Isomorphic State Channels -- 1 Introduction -- 2 Preliminaries -- 3 The Hydra Protocol -- 3.1 Protocol Setup -- 3.2 Mainchain (Simplified) -- 3.3 Head (Simplified) -- 3.4 Extensions for the Full Protocol -- 4 Experimental Evaluation -- 4.1 Applying the Methodology -- 4.2 Experimental Results -- 4.3 Larger Clusters -- 4.4 Discussion -- References -- Authentication and Usability -- What's in Score for Website Users: A Data-Driven Long-Term Study on Risk-Based Authentication Characteristics -- 1 Introduction -- 2 RBA Models -- 3 Data Set -- 4 Attacker Models -- 5 Evaluating RBA Practice (RQ1) -- 5.1 Results -- 5.2 Discussion -- 6 Analyzing RBA Features (RQ2) -- 6.1 Study Setup -- 6.2 Results -- 6.3 Discussion -- 7 Analyzing RBA Configuations (RQ3) -- 8 Limitations -- 9 Related Work -- 10 Conclusion -- A Survey -- A.1 Online Service -- A.2 Demographics -- B Features -- References.; DAHash: Distribution Aware Tuning of Password Hashing Costs.