Publications by Bryan Alexander Ford

Related publications (43)

Scalable Bias-Resistant Distributed Randomness

Bryan Alexander Ford, Philipp Svetolik Jovanovic, Linus Gasser, Eleftherios Kokoris Kogias, Nicolas Gailly, Ismail Khoffi

Bias-resistant public randomness is a critical component in many (distributed) protocols. Existing solutions do not scale to hundreds or thousands of participants, as is needed in many decentralized systems. We propose two large-scale distributed protocols ...

IEEE2017

PriFi: A Low-Latency and Tracking-Resistant Protocol for Local-Area Anonymous Communication

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

Popular anonymity mechanisms such as Tor provide low communication latency but are vulnerable to traffic analysis attacks that can de-anonymize users. Moreover, known traffic-analysis-resistant techniques such as Dissent are impractical for use in latency- ...

ACM2016

Sustainability and Ethicality are Peripheral to Students’ Software Design

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

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

Building Privacy-Preserving Cryptographic Credentials from Federated Online Identities

Bryan Alexander Ford

Federated identity providers, e.g., Facebook and PayPal, offer a convenient means for authenticating users to third-party applications. Unfortunately such cross-site authentications carry privacy and tracking risks. For example, federated identity provider ...

Association for Computing Machinery2016

Flash Freezing Flash Boys: Countering Blockchain Front-Running

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

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

Keeping Authorities “Honest or Bust” with Decentralized Witness Cosigning

Bryan Alexander Ford, Linus Gasser, Philipp Svetolik Jovanovic, Nicolas Gailly, Ismail Khoffi

The secret keys of critical network authorities – such as time, name, certificate, and software update services – represent high-value targets for hackers, criminals, and spy agencies wishing to use these keys secretly to compromise other hosts. To protect ...

IEEE2016

Breaking Blockchain Rationality with Out-of-Band Collusion

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

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

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

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

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

CALYPSO: Private Data Management for Decentralized Ledgers

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

Reducing Metadata Leakage from Encrypted Files and Communication with PURBs

Matthew Joshua Underwood, Jean-Pierre Hubaux, Bryan Alexander Ford, Ludovic Barman, Wouter Lueks, Kirill Nikitin

Most encrypted data formats leak metadata via their plaintext headers, such as format version, encryption schemes used, number of recipients who can decrypt the data, and even the recipients’ identities. This leakage can pose security and privacy risks to ...

Sciendo2019

On Enforcing the Digital Immunity of a Large Humanitarian Organization

Jean-Pierre Hubaux, Bryan Alexander Ford, Juan Ramón Troncoso-Pastoriza, Philipp Svetolik Jovanovic

Humanitarian action, the process of aiding individuals in situations of crises, poses unique information-security challenges due to natural or manmade disasters, the adverse environments in which it takes place, and the scale and multidisciplinary nature o ...

2018

Hang With Your Buddies to Resist Intersection Attacks

Bryan Alexander Ford

Some anonymity schemes, such as DC-nets and MIX cascades, can guarantee anonymity even against traffic analysis – provided messages are independent and unlinkable. Users in practice often desire pseudonymity – sending messages intentionally linkable to eac ...

2013

Seeking Anonymity in an Internet Panopticon

Bryan Alexander Ford

Internet, users often need to assume, by default, that their every statement or action online is monitored and tracked. The Dissent project at Yale University takes a collective approach to online anonymity, based on different algorithmic foundations from ...

2015

CHAINIAC: Proactive Software-Update Transparency via Collectively Signed Skipchains and Verified Builds

Bryan Alexander Ford, Linus Gasser, Philipp Svetolik Jovanovic, Eleftherios Kokoris Kogias, Nicolas Gailly, Ismail Khoffi, Kirill Nikitin

Software-update mechanisms are critical to the security of modern systems, but their typically centralized design presents a lucrative and frequently attacked target. In this work, we propose CHAINIAC, a decentralized software-update framework that elimina ...

USENIX Association2017

Proof-of-Personhood: Redemocratizing Permissionless Cryptocurrencies

Bryan Alexander Ford, Philipp Svetolik Jovanovic, Linus Gasser, Eleftherios Kokoris Kogias, Nicolas Gailly, Maria Fernanda Borge Chavez

Permissionless blockchain-based cryptocurrencies commonly use proof-of-work (PoW) or proof-of-stake (PoS) to ensure their security, e.g. to prevent double spending attacks. However, both approaches have disadvantages: PoW leads to massive amounts of wasted ...

IEEE2017

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

Moby: A Blackout-Resistant Anonymity Network for Mobile Devices

Bryan Alexander Ford, Antoine Rault

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

Rethinking General-Purpose Decentralized Computing

Bryan Alexander Ford, Eleftherios Kokoris Kogias, 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

UnLynx: A Decentralized System for Privacy-Conscious Data Sharing

Jean-Pierre Hubaux, Bryan Alexander Ford, Jean Louis Raisaro, Zhicong Huang, Joao André Gomes de Sá e Sousa, David Jules Froelicher, Christian Vincent Mouchet, Patricia Egger

Current solutions for privacy-preserving data sharing among multiple parties either depend on a centralized authority that must be trusted and provides only weakest-link security (e.g., the entity that manages private/secret cryptographic keys), or leverag ...

De Gruyter2017

Multiple Objectives of Lawful-Surveillance Protocols

Bryan Alexander Ford

In recent work on open, privacy-preserving, accountable surveillance, we have proposed the use of cryptographic protocols that enable law-enforcement and intelligence agencies to obtain actionable information about targeted users of mass-communication syst ...

2017