Publications related to Improving Fast Paxos: being optimistic with no overhead

Planetary-Scale Byzantine Fault Tolerance

The scale and pervasiveness of the Internet make it a pillar of planetary communication, industry and economy, as well as a fundamental medium for public discourse and democratic engagement. In stark contrast with the Internet's decentralized infrastructur ...

EPFL2024

Byzantine consensus is Θ(n^2): the Dolev-Reischuk bound is tight even in partial synchrony!

Rachid Guerraoui, Seth Gilbert, Vincent Gramoli, Manuel José Ribeiro Vidigueira, Jovan Komatovic, Pierre Philippe Civit

The Dolev-Reischuk bound says that any deterministic Byzantine consensus protocol has (at least) quadratic (in the number of processes) communication complexity in the worst case: given a system with n processes and at most f < n/3 failures, any solution t ...

2023

Hypergraph-Based Fast Distributed AC Power Flow Optimization

Colin Neil Jones, Yingzhao Lian, Yuning Jiang, Xinliang Dai

This paper presents a novel distributed approach for solving AC power flow (PF) problems. The optimization problem is reformulated into a distributed form using a communication structure corresponding to a hypergraph, by which complex relationships between ...

IEEE2023

The evolution of behavioral cues and signaling in displaced communication

Dario Floreano, Laurent Keller

Displaced communication, whereby individuals communicate regarding a subject that is not immediately present (spatially or temporally), is one of the key features of human language. It also occurs in a few animal species, most notably the honeybee, where t ...

2023

Non-verbal Communication between Humans and Robots: Imitation, Mutual Understanding and Inferring Object Properties

Nuno Ricardo Ferreira Duarte

Humans can express their actions and intentions, resorting to verbal and/or non-verbal communication. In verbal communication, humans use language to express, in structured linguistic terms, the desired action they wish to perform. Non-verbal communication ...

EPFL2023

As easy as ABC: Optimal (A)ccountable (B)yzantine (C)onsensus is easy!

Rachid Guerraoui, Seth Gilbert, Vincent Gramoli, Jovan Komatovic, Pierre Philippe Civit

It is known that the agreement property of the Byzantine consensus problem among n processes can be violated in a non-synchronous system if the number of faulty processes exceeds t0 = ┌n/3┐ − 1 [10], [19]. In this paper, we investigate the accountable Byza ...

IEEE2022

Byzantine Consensus is Θ(n^2): The Dolev-Reischuk Bound is Tight even in Partial Synchrony!

Rachid Guerraoui, Seth Gilbert, Vincent Gramoli, Manuel José Ribeiro Vidigueira, Jovan Komatovic, Pierre Philippe Civit

The Dolev-Reischuk bound says that any deterministic Byzantine consensus protocol has (at least) quadratic communication complexity in the worst case. While it has been shown that the bound is tight in synchronous environments, it is still unknown whether ...

Dagstuhl Publishing2022

Epidemic mitigation by statistical inference from contact tracing data

Maria Refinetti, Giovanni Catania, Florent Gérard Krzakala, Lenka Zdeborová, Indaco Biazzo

Contact tracing is an essential tool to mitigate the impact of a pandemic, such as the COVID-19 pandemic. In order to achieve efficient and scalable contact tracing in real time, digital devices can play an important role. While a lot of attention has been ...

National Academy of Sciences2021

Microsecond Consensus for Microsecond Applications

Rachid Guerraoui, Mihail Igor Zablotchi, Athanasios Xygkis, Naama Ben David

We consider the problem of making apps fault-tolerant through replication, when apps operate at the microsecond scale, as in finance, embedded computing, and microservices apps. These apps need a replication scheme that also operates at the microsecond sca ...

USENIX ASSOC2020

The Hidden Complexity of Distributed Systems

Karolos Antoniadis

The field of distributed computing has a long history, of more than fifty years. During that time, our understanding of the field has improved immensely and a certain body of folklore beliefs has formed. However, such folklore beliefs are not necessarily a ...

EPFL2020

Diffusion LMS With Communication Delays: Stability and Performance Analysis

Ali H. Sayed, Roula Nassif

We study the problem of distributed estimation over adaptive networks where communication delays exist between nodes. In particular, we investigate the diffusion Least-Mean-Square (LMS) strategy where delayed intermediate estimates (due to the communicatio ...

IEEE Institute of Electrical and Electronics Engineers2020

SBFT: a Scalable and Decentralized Trust Infrastructure

Dragos-Adrian Seredinschi

SBFT is a state of the art Byzantine fault tolerant state machine replication system that addresses the challenges of scalability, decentralization and global geo-replication. SBFT is optimized for decentralization and is experimentally evaluated on a depl ...

IEEE COMPUTER SOC2019

Fully-Asynchronous Cache-Efficient Simulation of Detailed Neural Networks

Felix Schürmann, Michael Lee Hines

Modern asynchronous runtime systems allow the re-thinking of large-scale scientific applications. With the example of a simulator of morphologically detailed neural networks, we show how detaching from the commonly used bulk-synchronous parallel (BSP) exec ...

SPRINGER INTERNATIONAL PUBLISHING AG2019

Communication trade-offs for Local-SGD with large step size

Aymeric Daphnis Kévin Dieuleveut

Synchronous mini-batch SGD is state-of-the-art for large-scale distributed machine learning. However, in practice, its convergence is bottlenecked by slow communication rounds between worker nodes. A natural solution to reduce communication is to use the " ...

NEURAL INFORMATION PROCESSING SYSTEMS (NIPS)2019

Exploring The Borderlands Of The Gathering Problem

Rachid Guerraoui, El Mahdi El Mhamdi, Alexandre David Olivier Maurer, Vladislav Tempez

Problems of pattern formation have been extensively studied in distributed computing. One of this problems is the gathering problem: agents must gather at a same position in a distributed manner. When gathering is not possible, a close problem is the conve ...

2019

A hybrid framework for industrial data storage and exploitation

Dimitrios Kyritsis, Foivos Psarommatis Giannakopoulos, Ioannis Tourkogiorgis

In this paper a hybrid framework is illustrated, with a software and hardware integration strategy, for an industrial platform that exploits features from a Relational Database (RDB) and Triplestore using the blackboard architectural pattern, ensuring effi ...

Elsevier2019

Innovation capacity of the agricultural sector: network of productive interactions, knowledge transfer and differentiation mechanisms

Camille Marguerite Aouinait

Economic growth is increasingly explained and driven by knowledge acquisition and firmsâ capabilities to adapt to new evolving situations to fit economic, societal and environmental frames. Strategic behavior of private companies in differentiating and p ...

EPFL2019

Optimized Quantization in Distributed Graph Signal Filtering

Pascal Frossard, Isabela Cunha Maia Nobre

Distributed graph signal processing algorithms require the network nodes to communicate by exchanging messages in order to achieve a common objective. These messages have a finite precision in realistic networks, which may necessitate to implement message ...

2019

Causal Consistency and Latency Optimality: Friend or Foe? [Extended Version]

Rachid Guerraoui, Willy Zwaenepoel, Junxiong Wang, Diego Didona

Causal consistency is an attractive consistency model for geo-replicated data stores. It is provably the strongest model that tolerates network partitions. It avoids the long latencies associated with strong consistency, and, especially when using read-onl ...

2018

Causal Consistency and Latency Optimality: Friend or Foe?

Rachid Guerraoui, Willy Zwaenepoel, Junxiong Wang, Diego Didona

Causal consistency is an attractive consistency model for geo-replicated data stores. It is provably the strongest model that tolerates network partitions. It avoids the long latencies associated with strong consistency, and, especially when using read-onl ...

ASSOC COMPUTING MACHINERY2018