Publications associées à Optimal Revocations in Ephemeral Networks: A Game-Theoretic Framework

Secure and Efficient Cryptographic Algorithms in a Quantum World

Since the advent of internet and mass communication, two public-key cryptographic algorithms have shared the monopoly of data encryption and authentication: Diffie-Hellman and RSA. However, in the last few years, progress made in quantum physics -- and mo ...

EPFL2024

On the Theory and Practice of Modern Secure Messaging

Daniel Patrick Collins

Billions of people now have conversations daily over the Internet. A large portion of this communication takes place via secure messaging protocols that offer "end-to-end encryption'" guarantees and resilience to compromise like the widely-used Double Ratc ...

EPFL2024

Side-channel analysis of isogeny-based key encapsulation mechanisms and hash-based digital signatures

Aymeric Genet

Current cryptographic solutions will become obsolete with the arrival of large-scale universal quantum computers. As a result, the National Institute of Standards and Technology supervises a post-quantum standardization process which involves evaluating ca ...

EPFL2024

Making Classical (Threshold) Signatures Post-quantum for Single Use on a Public Ledger

Serge Vaudenay, Laurane Chloé Angélina Marco, Abdullah Talayhan

The Bitcoin architecture heavily relies on the ECDSA signature scheme which is broken by quantum adversaries as the secret key can be computed from the public key in quantum polynomial time. To mitigate this attack, bitcoins can be paid to the hash of a pu ...

2023

Security in the Presence of Quantum Adversaries

Khashayar Barooti

With the looming threat of large-scale quantum computers, a fair portion of recent cryptographic research has focused on examining cryptographic primitives from the perspective of a quantum adversary. Shor's 1994 result revealed that quantum computers can ...

EPFL2023

Untangling the influence of Antarctic and Southern Ocean life on clouds

Jenny Thomas, Julia Schmale, Hélène Paule Angot, Markus Frey

Polar environments are among the fastest changing regions on the planet. It is a crucial time to make significant improvements in our understanding of how ocean and ice biogeochemical processes are linked with the atmosphere. This is especially true over A ...

2023

Quality-Constrained Encoding Optimization for Omnidirectional Video Streaming

Pascal Frossard, Roberto Gerson De Albuquerque Azevedo, Chaofan He

Omnidirectional video streaming is usually implemented based on the representations of tiles, where the tiles are obtained by splitting the video frame into several rectangular areas and each tile is converted into multiple representations with different r ...

Ieee-Inst Electrical Electronics Engineers Inc2023

Thwarting Malicious Adversaries in Homomorphic Encryption Pipelines

Sylvain Chatel

Homomorphic Encryption (HE) enables computations to be executed directly on encrypted data. As such, it is an auspicious solution for protecting the confidentiality of sensitive data without impeding its usability. However, HE does not provide any guarant ...

EPFL2023

Public-Key Encryption with Quantum Keys

Khashayar Barooti

In the framework of Impagliazzo's five worlds, a distinction is often made between two worlds, one where public-key encryption exists (Cryptomania), and one in which only one-way functions exist (MiniCrypt). However, the boundaries between these worlds can ...

Springer International Publishing Ag2023

BLOOM: Bimodal Lattice One-out-of-Many Proofs and Applications

Ngoc Khanh Karol Nguyen

We give a construction of an efficient one-out-of-many proof system, in which a prover shows that he knows the pre-image for one element in a set, based on the hardness of lattice problems. The construction employs the recent zero-knowledge framework of Ly ...

SPRINGER INTERNATIONAL PUBLISHING AG2022

Analysis and Improvements of the Sender Keys Protocol for Group Messaging

Daniel Patrick Collins

Messaging between two parties and in the group setting has enjoyed widespread attention both in practice, and, more recently, from the cryptographic community. One of the main challenges in the area is constructing secure (end-to- end encrypted) and effici ...

2022

A universal co-solvent dilution strategy enables facile and cost-effective fabrication of perovskite photovoltaics

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Sandy Sanchez Alonso, Narges Yaghoobi Nia, Linfeng Pan, Paramvir Ahlawat, Viacheslav Bolnykh, Dan Ren, Masaud Hassan S Almalki, Hong Zhang, Anurag Krishna, Tzu-Sen Su

Cost management and toxic waste generation are two key issues that must be addressed before the commercialization of perovskite optoelectronic devices. We report a ground-breaking strategy for eco-friendly and cost-effective fabrication of highly efficient ...

Nature Research2022

Attacks on some post-quantum cryptographic protocols: The case of the Legendre PRF and SIKE

Novak Kaluderovic

Post-quantum cryptography is a branch of cryptography which deals with cryptographic algorithms whose hardness assumptions are not based on problems known to be solvable by a quantum computer, such as the RSA problem, factoring or discrete logarithms. This ...

EPFL2022

Single-Trace Clustering Power Analysis of the Point-Swapping Procedure in the Three Point Ladder of Cortex-M4 SIKE

Aymeric Genet, Novak Kaluderovic

In this paper, the recommended implementation of the post-quantum key exchange SIKE for Cortex-M4 is attacked through power analysis with a single trace by clustering with the k-means algorithm the power samples of all the invocations of the elliptic curve ...

Springer, Cham2022

Optimal Symmetric Ratcheting for Secure Communication

Serge Vaudenay, Andrea Felice Caforio, Daniel Patrick Collins, Hailun Yan

To mitigate state exposure threats to long-lived instant messaging sessions, ratcheting was introduced, which is used in practice in protocols like Signal. However, existing ratcheting protocols generally come with a high cost. Recently, Caforio et al. pro ...

OXFORD UNIV PRESS2022

Sonomyographic Prosthetic Interacion: Online Simultaneous and Proportional Control of Wrist and Hand Motions Using Semisupervised Learning

Xingchen Yang

Human hands play a very important role in daily object manipulation. Current prosthetic hands are capable of mimicking most functions of the human hand, but how to interact with prosthetic hands based on human intentions remains an open problem. In this ar ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Re-focusing explainability in medicine

Using artificial intelligence to improve patient care is a cutting-edge methodology, but its implementation in clinical routine has been limited due to significant concerns about understanding its behavior. One major barrier is the explainability dilemma a ...

2022

Integrity and Metadata Protection in Data Retrieval

Kirill Nikitin

Secure retrieval of data requires integrity, confidentially, transparency, and metadata-privacy of the process. Existing protection mechanisms, however, provide only partially these properties: encryption schemes still expose cleartext metadata, protocols ...

EPFL2021

Akt Is S-Palmitoylated: A New Layer of Regulation for Akt

Françoise Gisou van der Goot Grunberg, Laurence Gouzi Abrami

The protein kinase Akt/PKB participates in a great variety of processes, including translation, cell proliferation and survival, as well as malignant transformation and viral infection. In the last few years, novel Akt posttranslational modifications have ...

FRONTIERS MEDIA SA2021

Complete Practical Side-Channel-Assisted Reverse Engineering of AES-Like Ciphers

Andrea Felice Caforio, Muhammed Fatih Balli, Subhadeep Banik

Public knowledge about the structure of a cryptographic system is a standard assumption in the literature and algorithms are expected to guarantee security in a setting where only the encryption key is kept secret. Nevertheless, undisclosed proprietary cry ...

SPRINGER INTERNATIONAL PUBLISHING AG2022