Publications related to National Security Agency

Green Cryptography and Other Optimisations

The spectral decomposition of cryptography into its life-giving components yields an interlaced network of tangential and orthogonal disciplines that are nonetheless invariably grounded by the same denominator: their implementation on commodity computing p ...

EPFL2023

The Side-channel Metrics Cheat Sheet

Francesco Regazzoni, Mirjana Stojilovic, Ognjen Glamocanin, Dorian Ros

Side-channel attacks exploit a physical observable originating from a cryptographic device in order to extract its secrets. Many practically relevant advances in the field of side-channel analysis relate to security evaluations of cryptographic functions a ...

2023

Bayes Security: A Not So Average Metric

Carmela González Troncoso, Giovanni Cherubin

Security system designers favor worst-case security metrics, such as those derived from differential privacy (DP), due to the strong guarantees they provide. On the downside, these guarantees result in a high penalty on the system's performance. In this pa ...

IEEE2023

Beyond Security and Efficiency: On-Demand Ratcheting with Security Awareness

Serge Vaudenay, Fatma Betül Durak, Andrea Felice Caforio

Secure asynchronous two-party communication applies ratcheting to strengthen privacy, in the presence of internal state exposures. Security with ratcheting is provided in two forms: forward security and post-compromise security. There have been several suc ...

2021

On Polar Coding For Finite Blocklength Secret Key Generation Over Wireless Channels

Yanina Yurina Shkel

We consider the problem of secret key generation from correlated Gaussian random variables in the finite blocklength regime. Such keys could be used to encrypt communication in IoT networks, and have provable secrecy guarantees in contrast to classic crypt ...

IEEE2020

X-Attack: Remote Activation of Satisfiability Don’t-Care Hardware Trojans on Shared FPGAs

Mirjana Stojilovic, Dina Gamaleldin Ahmed Shawky Mahmoud, Wei Hu

Albeit very appealing, FPGA multitenancy in the cloud computing environment is currently on hold due to a number of recently discovered vulnerabilities to side-channel attacks and covert communication. In this work, we successfully demonstrate a new attack ...

IEEE2020

A Digital Platform connecting Academia and Small Businesses: An opportunity for Knowledge Management Experiments

Quentin Adrien Cavillier

Digital transformation is one of the biggest phenomena of this decade. One enabler of this revolution was cloud computing. Today, software engineers can deliver software as a service (SaaS), which is accessible to users through the Internet. Slack, Shopify ...

EPFL2019

Practical Private Range Search in Depth

Odysseas Papapetrou, Ioannis Demertzis

We consider a data owner that outsources its dataset to an untrusted server. The owner wishes to enable the server to answer range queries on a single attribute, without compromising the privacy of the data and the queries. There are several schemes on “pr ...

2018

Towards Low Energy Stream Ciphers

Francesco Regazzoni, Subhadeep Banik, Willi Meier

Energy optimization is an important design aspect of lightweight cryptography. Since low energy ciphers drain less battery, they are invaluable components of devices that operate on a tight energy budget such as handheld devices or RFID tags. At Asiacrypt ...

2018

Provably Secure Authenticated Encryption

Damian Vizár

Authenticated Encryption (AE) is a symmetric key cryptographic primitive that ensures confidentiality and authenticity of processed messages at the same time. The research of AE as a primitive in its own right started in 2000. The security goals of AE wer ...

EPFL2018

Secure numerical and logical multi party operations

Bin Lu

We derive algorithms for efficient secure numerical and logical operations in the semi-honest model ensuring statistical or perfect security for secure multi-party computation (MPC). To derive our algorithms for trigonometric functions, we use basic mathem ...

Elsevier Science Bv2017

Some Cryptanalytic Results on Lizard

Subhadeep Banik

Lizard is a lightweight stream cipher proposed by Hamann, Krause and Meier in IACR ToSC 2017. It has a Grain-like structure with two state registers of size 90 and 31 bits. The cipher uses a 120 bit secret key and a 64 bit IV. The authors claim that Lizard ...

2017

An FPGA-Based 4 Mbps Secret Key Distillation Engine for Quantum Key Distribution Systems

Andreas Peter Burg, Jeremy Hugues-Felix Constantin, Nicholas Alexander Preyss, Pascal Junod

Quantum key distribution (QKD) enables provably secure communication between two parties over an optical fiber that arguably withstands any form of attack. Besides the need for a suitable physical signalling scheme and the corresponding devices, QKD also r ...

Springer2017

Circular Security Reconsidered

Serge Vaudenay, Fatma Betül Durak

The notion of circular security of pseudorandom functions (PRF) was introduced in Distance Bounding Protocols. So far, only a construction based on a random oracle model was proposed. Circular security stands between two new notions which we call Key Depen ...

Springer International Publishing2016

Practical Private Range Search Revisited

Odysseas Papapetrou, Ioannis Demertzis

We consider a data owner that outsources its dataset to an untrusted server. The owner wishes to enable the server to answer range queries on a single attribute, without compromising the privacy of the data and the queries. There are several schemes on "pr ...

2016

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

Keystroke Biometrics Ongoing Competition

Sébastien Marcel, André Anjos

This paper presents the first Keystroke Biometrics Ongoing Competition (KBOC) organized to establish a reproducible baseline in person authentication using keystroke biometrics. The competition has been developed using the BEAT platform and includes one of ...

2016

Privacy-preserving distributed collaborative filtering

Rachid Guerraoui, Anne-Marie Kermarrec, Davide Frey

We propose a new mechanism to preserve privacy while leveraging user profiles in distributed recommender systems. Our mechanism relies on two contributions: (i) an original obfuscation scheme, and (ii) a randomized dissemination protocol. We show that our ...

Springer Wien2016

Secret Communication Over Broadcast Erasure Channels With State-Feedback

Christina Fragouli, Suhas Diggavi, László Czap, Vinod Malathidevi Prabhakaran

We consider a 1-to-K communication scenario, where a source transmits private messages to K receivers through a broadcast erasure channel, and the receivers feedback strictly, causally, and publicly their channel states after each transmission. We explore ...

Ieee-Inst Electrical Electronics Engineers Inc2015

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