208 citations · 765 across the 27 of their papers we have counts for
26 papers · 1 filter
Obelia: Scaling DAG-Based Blockchains to Hundreds of Validators
George Danezis, Lefteris Kokoris-Kogias, Alberto Sonnino +1
Obelia improves upon structured DAG-based consensus protocols used in proof-of-stake systems, allowing them to effectively scale to accommodate hundreds of validators. Obelia imple…
Cuttlefish: Expressive Fast Path Blockchains with FastUnlock
Lefteris Kokoris-Kogias, Alberto Sonnino, George Danezis
Cuttlefish addresses several limitations of existing consensus-less and consensus-minimized decentralized ledgers, including restricted programmability and the risk of deadlocked a…
Zef: Low-latency, Scalable, Private Payments
Mathieu Baudet, Alberto Sonnino, Mahimna Kelkar +1
We introduce Zef, the first Byzantine-Fault Tolerant (BFT) protocol to support payments in anonymous digital coins at arbitrary scale. Zef follows the communication and security mo…
Narwhal and Tusk: A DAG-based Mempool and Efficient BFT Consensus
George Danezis, Eleftherios Kokoris Kogias, Alberto Sonnino +1
We propose separating the task of reliable transaction dissemination from transaction ordering, to enable high-performance Byzantine fault-tolerant quorum-based consensus. We desig…
FastPay: High-Performance Byzantine Fault Tolerant Settlement
Mathieu Baudet, George Danezis, Alberto Sonnino
FastPay allows a set of distributed authorities, some of which are Byzantine, to maintain a high-integrity and availability settlement system for pre-funded payments. It can be use…
SybilQuorum: Open Distributed Ledgers Through Trust Networks
Alberto Sonnino, George Danezis
The Sybil attack plagues all peer-to-peer systems, and modern open distributed ledgers employ a number of tactics to prevent it from proof of work, or other resources such as space…
Replay Attacks and Defenses Against Cross-shard Consensus in Sharded Distributed Ledgers
Alberto Sonnino, Shehar Bano, Mustafa Al-Bassam +1
We present a family of replay attacks against sharded distributed ledgers, that target cross-shard consensus protocols, such as the recently proposed Chainspace and Omniledger. The…
Blockmania: from Block DAGs to Consensus
George Danezis, David Hrycyszyn
Blockmania is a byzantine consensus protocol. Nodes emit blocks forming a directed acyclic graph (block DAG) that is subsequently interpreted by each node separately to ensure cons…
TARANET: Traffic-Analysis Resistant Anonymity at the NETwork layer
Chen Chen, Daniele E. Asoni, Adrian Perrig +3
Modern low-latency anonymity systems, no matter whether constructed as an overlay or implemented at the network layer, offer limited security guarantees against traffic analysis. O…
Coconut: Threshold Issuance Selective Disclosure Credentials with Applications to Distributed Ledgers
Alberto Sonnino, Mustafa Al-Bassam, Shehar Bano +2
Coconut is a novel selective disclosure credential scheme supporting distributed threshold issuance, public and private attributes, re-randomization, and multiple unlinkable select…
Consensus in the Age of Blockchains
Shehar Bano, Alberto Sonnino, Mustafa Al-Bassam +4
The blockchain initially gained traction in 2008 as the technology underlying bitcoin, but now has been employed in a diverse range of applications and created a global market wort…
A Touch of Evil: High-Assurance Cryptographic Hardware from Untrusted Components
Vasilios Mavroudis, Andrea Cerulli, Petr Svenda +3
The semiconductor industry is fully globalized and integrated circuits (ICs) are commonly defined, designed and fabricated in different premises across the world. This reduces prod…
Mix-ORAM: Using delegate shuffles
Raphael R. Toledo, George Danezis, Isao Echizen
Oblivious RAM (ORAM) is a key technology for providing private storage and querying on untrusted machines but is commonly seen as impractical due to the high overhead of the re-ran…
Chainspace: A Sharded Smart Contracts Platform
Mustafa Al-Bassam, Alberto Sonnino, Shehar Bano +2
Chainspace is a decentralized infrastructure, known as a distributed ledger, that supports user defined smart contracts and executes user-supplied transactions on their objects. Th…
Learning Universal Adversarial Perturbations with Generative Models
Jamie Hayes, George Danezis
Neural networks are known to be vulnerable to adversarial examples, inputs that have been intentionally perturbed to remain visually similar to the source input, but cause a miscla…
ClaimChain: Improving the Security and Privacy of In-band Key Distribution for Messaging
Bogdan Kulynych, Wouter Lueks, Marios Isaakidis +2
The social demand for email end-to-end encryption is barely supported by mainstream service providers. Autocrypt is a new community-driven open specification for e-mail encryption…
LOGAN: Membership Inference Attacks Against Generative Models
Jamie Hayes, Luca Melis, George Danezis +1
Generative models estimate the underlying distribution of a dataset to generate realistic samples according to that distribution. In this paper, we present the first membership inf…
Systematizing Decentralization and Privacy: Lessons from 15 Years of Research and Deployments
Carmela Troncoso, Marios Isaakidis, George Danezis +1
Decentralized systems are a subset of distributed systems where multiple authorities control different components and no authority is fully trusted by all. This implies that any co…
The Loopix Anonymity System
Ania Piotrowska, Jamie Hayes, Tariq Elahi +2
We present Loopix, a low-latency anonymous communication system that provides bi-directional 'third-party' sender and receiver anonymity and unobservability. Loopix leverages cover…
A Public Comment on NCCoE's White Paper on Privacy-Enhancing Identity Brokers
Luís T. A. N. Brandão, Nicolas Christin, George Danezis
The National Cybersecurity Center of Excellence (NCCoE) (in the United States) has published on October 19, 2015, a white paper on "privacy-enhanced identity brokers." We present h…
k-fingerprinting: a Robust Scalable Website Fingerprinting Technique
Jamie Hayes, George Danezis
Website fingerprinting enables an attacker to infer which web page a client is browsing through encrypted or anonymized network connections. We present a new website fingerprinting…
Efficient Private Statistics with Succinct Sketches
Luca Melis, George Danezis, Emiliano De Cristofaro
Large-scale collection of contextual information is often essential in order to gather statistics, train machine learning models, and extract knowledge from data. The ability to do…
HORNET: High-speed Onion Routing at the Network Layer
Chen Chen, Daniele Enrico Asoni, David Barrera +2
We present HORNET, a system that enables high-speed end-to-end anonymous channels by leveraging next generation network architectures. HORNET is designed as a low-latency onion rou…
Centrally Banked Cryptocurrencies
George Danezis, Sarah Meiklejohn
Current cryptocurrencies, starting with Bitcoin, build a decentralized blockchain-based transaction ledger, maintained through proofs-of-work that also generate a monetary supply.…