Decenter Seminar: Joachim Matthias Neu, Monday, March 27 at 3:30
Decenter Seminar Speaker: Joachim Matthias Neu, Stanford University Day: Monday, March 27, 2023 Time: 3:30-4:30pm Location: CS 105 Host: Pramod Viswanath Title: Internet-Scale Consensus In The Blockchain Era Abstract: Blockchains have ignited interest in Internet-scale consensus as a fundamental building block for decentralized applications and services, which in turn promise more egalitarian access and improved robustness to faults and abuse. While consensus has been studied in distributed systems for decades, Internet-scale consensus requires a fundamental rethinking of models, desiderata, and protocols. Participants are no longer a handful of computers in one company's data centers, but numerous mistrustful entities distributed across the Internet. I will discuss two examples of challenges and solutions for this new setting: (1) Ethereum, the second largest blockchain, aims to strengthen consensus liveness under open participation where parties come and go at will, and to strengthen safety to enable accountability in case of any safety violation. However, we show that no traditional single-ledger protocol can satisfy both strengthened properties simultaneously. To resolve this dilemma, we develop the multi-ledger consensus paradigm that is now the security design-specification for Ethereum. A by-product of this work are attacks on Ethereum's consensus protocol that prompted design changes. (2) Traditional network models do not capture rate constraints on communication and processing, leaving popular "provably secure" protocols vulnerable to attack. We show via a new queuing-based model how to schedule message handling securely. Our policies are simple enough to be forward-deployed at Internet service providers via a system that can also protect traffic of applications beyond blockchains. Bio: Joachim Neu is a PhD candidate at Stanford University with David Tse. His research focuses on the science and engineering of Internet-scale consensus as a fundamental building block for decentralized systems, using tools from distributed systems, applied probability, networking and communications, and applied cryptography. While a Masters student at Technical University of Munich, he worked in information and coding theory. Joachim has received the Protocol Labs PhD Fellowship and the Stanford Graduate Fellowship.
Decenter Seminar Speaker: Joachim Matthias Neu, Stanford University Day: Monday, March 27, 2023 Time: 3:30-4:30pm Location: CS 105 Host: Pramod Viswanath Event page: [ https://www.cs.princeton.edu/events/26369 | https://www.cs.princeton.edu/events/26369 ] Title: Internet-Scale Consensus In The Blockchain Era Abstract: Blockchains have ignited interest in Internet-scale consensus as a fundamental building block for decentralized applications and services, which in turn promise more egalitarian access and improved robustness to faults and abuse. While consensus has been studied in distributed systems for decades, Internet-scale consensus requires a fundamental rethinking of models, desiderata, and protocols. Participants are no longer a handful of computers in one company's data centers, but numerous mistrustful entities distributed across the Internet. I will discuss two examples of challenges and solutions for this new setting: (1) Ethereum, the second largest blockchain, aims to strengthen consensus liveness under open participation where parties come and go at will, and to strengthen safety to enable accountability in case of any safety violation. However, we show that no traditional single-ledger protocol can satisfy both strengthened properties simultaneously. To resolve this dilemma, we develop the multi-ledger consensus paradigm that is now the security design-specification for Ethereum. A by-product of this work are attacks on Ethereum's consensus protocol that prompted design changes. (2) Traditional network models do not capture rate constraints on communication and processing, leaving popular "provably secure" protocols vulnerable to attack. We show via a new queuing-based model how to schedule message handling securely. Our policies are simple enough to be forward-deployed at Internet service providers via a system that can also protect traffic of applications beyond blockchains. Bio: Joachim Neu is a PhD candidate at Stanford University with David Tse. His research focuses on the science and engineering of Internet-scale consensus as a fundamental building block for decentralized systems, using tools from distributed systems, applied probability, networking and communications, and applied cryptography. While a Masters student at Technical University of Munich, he worked in information and coding theory. Joachim has received the Protocol Labs PhD Fellowship and the Stanford Graduate Fellowship.
Decenter Seminar Speaker: Matheus Venturyne Xavier Ferreira *22, Harvard University Day: Tuesday, April 11 Time: 10:30am to 11:30am Location: CS 105 Host: Matt Weinberg Event page: https://www.cs.princeton.edu/events/26362 Title: Transparency and Security via Algorithmic Economics Abstract: Traditionally one assumes a regulator (or potential future consumers) would punish a platform for deviating from its promised specification. However, this is not always possible, even with publicly available data. For example, auctions are the main building block of how we transact on eBay or how Google sells advertising; however, it is impossible to know whether or not a self-interested auctioneer is also bidding in their auction with a fake identity. In this light, algorithmic economics provides a new perspective on designing secure systems because, in many real-world applications, adversaries are not intentionally malicious but rather rational and economically driven. First, I will overview the challenges of designing Internet auctions when auctioneers are not trusted and show a cryptographic auction that overcomes known impossibility results from economic theory. Beyond auctions, distributed systems like blockchains aim to enable more transparent platforms. In the second part, I will overview my contributions toward the design of incentive-compatible sustainable blockchains and show applications to the design of more transparent and secure platforms. Bio: Matheus Venturyne Xavier Ferreira is a Postdoctoral Fellow in Computer Science at Harvard John A. Paulson School of Engineering and Applied Sciences. He holds a Ph.D. (2022) and a MA (2018) in Computer Science from Princeton University and a BS in Computer Engineering (2016) from the Federal University of Itajubá. His primary research interests are in security, algorithmic economics, and cryptography. His honors include a CNS Prize for Excellence in Networking from UC, San Diego (2014), a Dean’s Grand from Princeton Graduate School (2016-2021), a LATinE Fellowship (2020) from Purdue College of Engineering, and an Award for Excellence from Princeton School of Engineering (2020). Matheus is from Itabira, which is known as the Brazilian capital of poetry.
participants (1)
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Emily C. Lawrence