Filters








150 Hits in 1.4 sec

Modelling Timeouts without Timelocks [chapter]

Howard Bowman
1999 Lecture Notes in Computer Science  
We address the issue of modelling a simple timeout in timed automata. We argue that expression of the timeout in the UPPAAL timed automata model is unsatisfactory.  ...  Speci cally, the solutions we explore either allow timelocks or are prohibitively complex.  ...  These characteristics of timelocks will be illustrated in section 2. This paper addresses the issue of how to model timeouts without generating timelocks.  ... 
doi:10.1007/3-540-48778-6_20 fatcat:hdnw5wbslbfyjn6i6am5p5e2km

Atomic Cross-Chain Swaps

Maurice Herlihy
2018 Proceedings of the 2018 ACM Symposium on Principles of Distributed Computing - PODC '18  
A cross-chain swap is modeled as a directed graph D, whose vertexes are parties and whose arcs are proposed asset transfers.  ...  For any pair (D, L), where D = (V , A) is a strongly-connected directed graph and L ⊂ V a feedback vertex set for D, we give an atomic cross-chain swap protocol for D, using a form of hashed timelock contracts  ...  If Carol were to post her contract with Alice before Bob posts his contract with Carol, then Alice could take ownership of the Cadillac without paying Carol. Timelock values matter.  ... 
doi:10.1145/3212734.3212736 fatcat:v5z6pedpvvgcpo6s47l5bmmpw4

Atomic Cross-Chain Swaps [article]

Maurice Herlihy
2018 arXiv   pre-print
A cross-chain swap is modeled as a directed graph D, whose vertexes are parties and whose arcs are proposed asset transfers.  ...  For any pair ( D,L), where D = (V,A) is a strongly-connected directed graph and L ⊂ V a feedback vertex set for D, we give an atomic cross-chain swap protocol for D, using a form of hashed timelock contracts  ...  If Carol were to post her contract with Alice before Bob posts his contract with Carol, then Alice could take ownership of the Cadillac without paying Carol. Timelock values ma er.  ... 
arXiv:1801.09515v4 fatcat:bz7r7shzhfhsvopbavdzckcmhe

Cross-chain Deals and Adversarial Commerce [article]

Maurice Herlihy and Barbara Liskov and Liuba Shrira
2019 arXiv   pre-print
Both commit protocols use timeout mechanisms based on path signatures. Zakhary et al. [45] propose a cross-chain commitment protocol that does not use hashed timelocks.  ...  The timelock protocol satisfies weak liveness: no compliant party's outgoing assets are locked up forever. Proof. Every escrow created by a compliant party has a finite timeout. Theorem 3.  ... 
arXiv:1905.09743v4 fatcat:66j2tfby7nhvpfkdrre37mgkse

Cross-chain deals and adversarial commerce

Maurice Herlihy, Barbara Liskov, Liuba Shrira
2021 The VLDB journal  
We also prove that some degree of centralization is required in the semi-synchronous communication model.  ...  For example, in the timelock protocol, parties must respect timeouts to remain compliant: a persistent denial-of-service attack may cause a party to miss a timeout, deviate from the protocol, and lose  ...  and the timeout delay Δ.  ... 
doi:10.1007/s00778-021-00686-1 fatcat:sbnapgocdnbibddemyicwqq64m

Time-Dilation Attacks on the Lightning Network [article]

Antoine Riard, Gleb Naumenko
2020 arXiv   pre-print
Allows him to get paid by presenting a preimage before timelock expiration. • Timeout transaction, used by Bob to spend a received output on Alice's commitment transaction to refund himself after timelock  ...  It allows her to get paid by presenting a preimage before timelock expiration. For every offered or received HTLC output, Alice must have a corresponding HTLC-Success or HTLC-Timeout transaction.  ... 
arXiv:2006.01418v1 fatcat:biec6xlpwbeildzlng4n76so44

Invited Paper: Failure is (literally) an Option: Atomic Commitment vs Optionality in Decentralized Finance [article]

Daniel Engel and Maurice Herlihy and Yingjie Xue
2021 arXiv   pre-print
The choice of timeouts is critical: if Bob's timeout were 2∆ instead of ∆, then Alice could wait until the timeout was about to expire to claim Bob's florins, leaving Bob without enough time to claim Alice's  ...  . ∆ Alice deposits her premium p a +p b on the florin blockchain's escrow contract with timelock t B = 5∆. 2∆ Bob deposits his premium on the guilder blockchain's escrow contract with timelock t A = 6∆  ... 
arXiv:2109.12167v1 fatcat:zzhqptgeavfhdgv4juwrlozg34

CLoTH: A Lightning Network Simulator

Marco Conoscenti, Antonio Vetrò, Juan Carlos De Martin
2021 SoftwareX  
The timelock is the Bitcoin implementation of a timeout: if the timeout expires, the contract is failed and the payment does not occur.  ...  Otherwise, if Bob does not show R within a certain timeout, the payment does not take place. It is called hashed timelock contract because it contains both an hash and a timelock.  ... 
doi:10.1016/j.softx.2021.100717 fatcat:ydd6b435lfe4znn2e33663k4oq

XCC: Theft-Resilient and Collateral-Optimized Cryptocurrency-Backed Assets [article]

Theodore Bugnet, Alexei Zamyatin
2022 IACR Cryptology ePrint Archive  
By making use of periodic, timelocked commitments on the backing blockchain, XCC decouples locked collateral from issued CBAS, allowing fractional collateralization without loss of security.  ...  XCC is compatible with the majority of existing blockchains without modification.  ...  Impossibility, Assumptions, and Models: Unfortunately, cross-chain communication is not solvable without a trusted third party [36] .  ... 
dblp:journals/iacr/BugnetZ22 fatcat:lkwo7doxjffa7g7bmespvwiiv4

Open problems in cross-chain protocols [article]

Thomas Eizinger and Philipp Hoenisch and Lucas Soriano del Pino
2021 arXiv   pre-print
Timelocks Timelocks are a common component of blockchain protocols.  ...  Without access to the latest state, the protocol's state machine cannot advance.  ... 
arXiv:2101.12412v1 fatcat:5bnbb7ywdnbfrhcsrs6ppcg4ae

How to stop time stopping

Howard Bowman, Rodolfo Gómez
2006 Formal Aspects of Computing  
models.  ...  the occurrence of zeno-timelocks.  ...  Acknowledgments We thank Li Su for his contribution to the theory and the implementation of the zeno-timelock checker. We also thank the reviewers for so many helpful comments.  ... 
doi:10.1007/s00165-006-0010-7 fatcat:d7cvbbmdabhutofjefc5ratpba

Atomic Cross-Chain Swaps with Improved Space and Local Time Complexity [article]

Soichiro Imoto, Yuichi Sudo, Hirotsugu Kakugawa, Toshimitsu Masuzawa
2019 arXiv   pre-print
Herlihy [Herlihy, 2018] invented this protocol by using hashed timelock contracts. A cross-chain swap is modeled as a directed graph D = (V,A).  ...  Herlihy's protocol uses the graph topology and signature information to set appropriate hashed timelock contracts.  ...  Our model has a sufficient power to represent this assumption.  ... 
arXiv:1905.09985v2 fatcat:x272ebf7qnc3zhpce3kdp56zeu

SyncPCN/PSyncPCN: Payment Channel Networks without Blockchain Synchrony [article]

Oğuzhan Ersoy and Jérémie Decouchant and Satwik Prabhu Kimble and Stefanie Roos
2022 arXiv   pre-print
Payment channel networks (PCNs) enhance the scalability of blockchains by allowing parties to conduct transactions off-chain, i.e, without broadcasting every transaction to all blockchain participants.  ...  However, from the brief discussion given in the paper, it is unclear how to guarantee progress, i.e., how to ensure that payments are eventually either successful or revoked, without timeouts.  ...  Model and Overview Threat Model. Committees in PSyncPCN are assumed to contain at most 𝑓 faulty members out of 𝑛 ≥ 3𝑓 +1 members.  ... 
arXiv:2207.11615v2 fatcat:ikfebxs7wzcunfgaaps4xxuba4

Sleepy Channels: Bitcoin-Compatible Bi-directional Payment Channels without Watchtowers [article]

Lukas Aumayr, Sri Aravinda Krishnan Thyagarajan, Giulio Malavolta, Pedro Monero-Sánchez, Matteo Maffei
2021 IACR Cryptology ePrint Archive  
Payment channels (PC) are a promising solution to the scalability issue of cryptocurrencies, allowing users to perform the bulk of the transactions off-chain without needing to post everything on the blockchain  ...  We present Sleepy Channels, the first bi-directional PC protocol without watchtowers (or any other third party) that supports an unbounded number of payments and does not require parties to be persistently  ...  We model security in the universal composability framework with global setup [9] , which lets us model concurrent executions.  ... 
dblp:journals/iacr/AumayrTMMM21 fatcat:ujml75egxfhnnjdw65nw7ypgfm

CLoTH: a Simulator for HTLC Payment Networks [article]

Marco Conoscenti, Antonio Vetrò, Juan Carlos De Martin, Federico Spini, Fabio Castaldo, Sebastiano Scròfina
2018 arXiv   pre-print
Alice pays 0.1 BTC to Berto if Berto can demonstrate to know a value R within a certain timeout (timelock, in the Bitcoin jargon): in this case, the HTLC is fulfilled; otherwise, 0.1 BTC returns back to  ...  Formal Model Having a network with N nodes connected by payment channels and having M payments to be executed on this network, the simulator formal model can be expressed using the following formulas:  ...  It runs the Dijkstra's algorithm, using timelock and fee as distance metric.  ... 
arXiv:1812.09940v1 fatcat:w7sqfscpczahvdvrs75h7tvlt4
« Previous Showing results 1 — 15 out of 150 results