Publications de Bryan Alexander Ford

E-Vote Your Conscience: Perceptions of Coercion and Vote Buying, and the Usability of Fake Credentials in Online Voting

Simone Maria Stefano Colombo, Bryan Alexander Ford, Haoqian Zhang, Louis-Henri Manuel Jakob Merino, Verónica del Carmen Estrada Galiñanes

Online voting is attractive for convenience and accessibility, but is more susceptible to voter coercion and vote buying than in-person voting. One mitigation is to give voters fake voting credentials that they can yield to a coercer. Fake credentials appe ...

IEEE2024

Breaking Blockchain Rationality with Out-of-Band Collusion

Bryan Alexander Ford, Haoqian Zhang, Louis-Henri Manuel Jakob Merino, Verónica del Carmen Estrada Galiñanes, Mahsa Bastankhah

Blockchain systems often rely on rationality assumptions for their security, expecting that nodes are motivated to maximize their profits. These systems thus design their protocols to incentivize nodes to execute the honest protocol but fail to consider ou ...

Springer International Publishing Ag2024

ZeroAuction: Zero-Deposit Sealed-Bid Auction via Delayed Execution

Bryan Alexander Ford, Haoqian Zhang, Verónica del Carmen Estrada Galiñanes

Auctions, a long-standing method of trading goods and services, are a promising use case for decentralized finance. However, due to the inherent transparency property of blockchains, current sealed-bid auction implementations on smart contracts requires a ...

Springer Science and Business Media Deutschland GmbH2024

Authenticated private information retrieval

Simone Maria Stefano Colombo, Kirill Nikitin, Bryan Alexander Ford, Henry Nathaniel Corrigan-Gibbs

This paper introduces protocols for authenticated private information retrieval. These schemes enable a client to fetch a record from a remote database server such that (a) the server does not learn which record the client reads, and (b) the client either ...

Usenix Assoc2023

QuePaxa: Escaping the Tyranny of Timeouts in Consensus

Bryan Alexander Ford, Cristina Basescu, Verónica del Carmen Estrada Galiñanes

Leader-based consensus algorithms are fast and efficient under normal conditions, but lack robustness to adverse conditions due to their reliance on timeouts for liveness. We present QuePaxa, the first protocol offering state-of-the-art normal-case efficie ...

Assoc Computing Machinery2023

Sustainability and Ethicality are Peripheral to Students’ Software Design

Pierluca Borsò, Siara Ruth Isaac, Bryan Alexander Ford, Aditi Kothiyal

The conceptual design phase is a fascinating moment to observe how a design task is interpreted, as the (often implicit) relative importance students accord to the various requirements and constraints offers a window into the thinking underpinning their de ...

Tempus Publications2023

Moby: A Blackout-Resistant Anonymity Network for Mobile Devices

Antoine Rault, Bryan Alexander Ford, Amogh Pradeep, Hira Javaid

Internet blackouts are challenging environments for anonymity and censorship resistance. Existing popular anonymity networks (e.g., Freenet, I2P, Tor) rely on Internet connectivity to function, making them impracticable during such blackouts. In such a set ...

2022

Flash Freezing Flash Boys: Countering Blockchain Front-Running

Bryan Alexander Ford, Haoqian Zhang, Louis-Henri Manuel Jakob Merino, Verónica del Carmen Estrada Galiñanes

Front-running, the practice of benefiting from advanced knowledge of pending transactions, has proliferated in the cryptocurrency space with the emergence of decentralized finance. Front-running causes devastating losses to honest participants-estimated at ...

IEEE2022

Technologizing Democracy or Democratizing Technology? A Layered-Architecture Perspective on Potentials and Challenges

Bryan Alexander Ford

While technology is often claimed to be “democratizing”, the technologizing of society has more often yielded undemocratic or even anti-democratic outcomes. Is technology fundamentally at odds with democracy, or is it merely a rich and infinitely-adaptable ...

University of Chicago Press2021

Immunizing Systems from Distant Failures by Limiting Lamport Exposure

Bryan Alexander Ford, Cristina Basescu

Failures far away from a user should intuitively be less likely to affect that user. Today's ecosystem miserably fails this test, however, despite high-availability best practices. Correlated and cascading failures – triggered by misconfigurations, bugs, a ...

Association for Computing Machinery2021

CALYPSO: Private Data Management for Decentralized Ledgers

Linus Gasser, Eleftherios Kokoris Kogias, Bryan Alexander Ford, Philipp Svetolik Jovanovic, Enis Ceyhun Alp

Distributed ledgers provide high availability and integrity, making them a key enabler for practical and secure computation of distributed workloads among mutually distrustful parties. Many practical applications also require strong confidentiality, howeve ...

2021

Using “proof of personhood” to tackle social media risks

Bryan Alexander Ford

The ease of creating fake virtual identities plays an important role in shaping the way information — and misinformation — circulates online. Social media platforms are increasingly prominent in shaping public debates, and the tension between online anonym ...

International Risk Governance Center (IRGC)2021

Asynchronous distributed coordination and consensus with threshold logical clocks

Bryan Alexander Ford

Consensus protocols for asynchronous networks are usually complex and inefficient, leading practical systems to rely on synchronous protocols. The invention proposes an approach to simplify asynchronous consensus by building it atop a novel threshold logic ...

2021

PriFi: Low-Latency Anonymity for Organizational Networks

Jean-Pierre Hubaux, Ludovic Barman, Ennan Zhai, Italo Ivan Dacosta Petrocelli, Bryan Alexander Ford, Mahdi Zamani, Apostolos Pyrgelis

Organizational networks are vulnerable to traffic-analysis attacks that enable adversaries to infer sensitive information from the network traffic – even if encryption is used. Typical anonymous communication networks are tailored to the Internet and are p ...

2020

MedChain: Accountable and Auditable Data Sharing in Distributed Medical Scenarios

Jean-Pierre Hubaux, Linus Gasser, Jean Louis Raisaro, Bryan Alexander Ford, Juan Ramón Troncoso-Pastoriza

The current trend towards personalized medicine creates an urgent need to share data among different hospitals and health institutions, which endangers the privacy of the data subjects if not done with the appropriate precautions. Conversely, the frequency ...

2019

MorphIT: Morphing Packet Reports for Internet Transparency

Aikaterini Argyraki, Bryan Alexander Ford, Georgia Fragkouli

Can we improve Internet transparency without worsening user anonymity? For a long time, researchers have been proposing transparency systems, where traffic reports produced at strategic network points help assess network behavior and verify service-level a ...

Sciendo2019

MedCo: Enabling Secure and Privacy-Preserving Exploration of Distributed Clinical and Genomic Data

Jean-Pierre Hubaux, Olivier Michielin, Mickaël Misbach, Jean Louis Raisaro, Bryan Alexander Ford, Joao André Gomes de Sá e Sousa, Juan Ramón Troncoso-Pastoriza

The increasing number of health-data breaches is creating a complicated environment for medical-data sharing and, consequently, for medical progress. Therefore, the development of new solutions that can reassure clinical sites by enabling privacy-preservin ...

2019

Methods and systems for secure data exchange

Linus Gasser, Eleftherios Kokoris Kogias, Bryan Alexander Ford

The present invention concerns a computer-implemented method for secure data exchange between a sender (A) and a recipient (B), wherein the method is performed by the sender (A) and comprises encrypting data using a symmetric key k, creating a write transa ...

2019

On the Security of Two-Round Multi-Signatures

Bryan Alexander Ford, Manu Drijvers, Kasra Edalatnejadkhamene

A multi-signature scheme allows a group of signers to collaboratively sign a message, creating a single signature that convinces a verifier that every individual signer approved the message. The increased interest in technologies to decentralize trust has ...

IEEE Computer Society2019

Rethinking General-Purpose Decentralized Computing

Eleftherios Kokoris Kogias, Bryan Alexander Ford, Georgia Fragkouli, Enis Ceyhun Alp

While showing great promise, smart contracts are difficult to program correctly, as they need a deep understanding of cryptography and distributed algorithms, and offer limited functionality, as they have to be deterministic and cannot operate on secret da ...

Association for Computing Machinery2019