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Concept

Pre-shared key

Publications associées (24)

Secure and Efficient Cryptographic Algorithms in a Quantum World

Loïs Evan Huguenin-Dumittan

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

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

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

Atom: A Stream Cipher with Double Key Filter

Subhadeep Banik, Andrea Felice Caforio

It has been common knowledge that for a stream cipher to be secure against generic TMD tradeoff attacks, the size of its internal state in bits needs to be at least twice the size of the length of its secret key. In FSE 2015, Armknecht and Mikhalev however ...

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

Symmetric Asynchronous Ratcheted Communication with Associated Data

Serge Vaudenay, Hailun Yan

Following up mass surveillance and privacy issues, modern secure communication protocols now seek strong security, such as forward secrecy and post-compromise security, in the face of state exposures. To address this problem, ratcheting was thereby introdu ...

Springer, Cham2020

Are Cloud FPGAs Really Vulnerable to Power Analysis Attacks?

Francesco Regazzoni, Mirjana Stojilovic, Ognjen Glamocanin, Louis Coulon

Recent works have demonstrated the possibility of extracting secrets from a cryptographic core running on an FPGA by means of remote power analysis attacks. To mount these attacks, an adversary implements a voltage fluctuation sensor in the FPGA logic, rec ...

IEEE2020

Cryptanalysis of Plantlet

Subhadeep Banik, Khashayar Barooti

Plantlet is a lightweight stream cipher designed by Mikhalev, Armknecht and Muller in IACR ToSC 2017. It has a Grain-like structure with two state registers of size 40 and 61 bits. In spite of this, the cipher does not seem to lose in security against gene ...

2019

Misuse Attacks on Post-quantum Cryptosystems

Serge Vaudenay, Fatma Betül Durak, Loïs Evan Huguenin-Dumittan, Abdullah Talayhan

Many post-quantum cryptosystems which have been proposed in the National Institute of Standards and Technology (NISI) standardization process follow the same meta-algorithm, but in different algebras or different encoding methods. They usually propose two ...

SPRINGER INTERNATIONAL PUBLISHING AG2019

On Design of Robust Lightweight Stream Cipher with Short Internal State

Subhadeep Banik

The stream cipher Sprout with a short internal state was proposed in FSE 2015. Although the construction guaranteed resistance to generic Time Memory Data Tradeoff attacks, there were some weaknesses in the design and the cipher was completely broken. In t ...

2018

Signature Schemes Secure Against Hard-to-Invert Leakage

Sebastian Faust

Side-channel attacks allow the adversary to gain partial knowledge of the secret key when cryptographic protocols are implemented in real-world hardware. The goal of leakage resilient cryptography is to design cryptosystems that withstand such attacks. In ...

Springer2016

Efficient Public-Key Distance Bounding Protocol

Serge Vaudenay, Handan Kilinç Alper

Distance bounding protocols become more and more important because they are the most accurate solution to defeat relay attacks. They consist of two parties: a verifier and a prover. The prover shows that (s)he is close enough to the verifier. In some appli ...

Springer-Verlag Berlin2016

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

Algebraic Cryptanalysis of Deterministic Symmetric Encryption

Petr Susil

Deterministic symmetric encryption is widely used in many cryptographic applications. The security of deterministic block and stream ciphers is evaluated using cryptanalysis. Cryptanalysis is divided into two main categories: statistical cryptanalysis and ...

EPFL2015

Secure Wireless Communications via Cooperative Transmitting

Ninoslav Marina

Information-theoretic secrecy is combined with cryptographic secrecy to create a secret-key exchange protocol for wireless networks. A network of transmitters, which already have cryptographically secured channels between them, cooperate to exchange a secr ...

Hindawi Publishing Corporation2014

Secure Communication in Erasure Networks with State-feedback

László Czap

The security and efficiency of communication are two of the main concerns for networks of today and the future. Our understanding of how to efficiently send information over various channels and networks has significantly increased in the past decade (see ...

EPFL2014

On Selecting the Nonce Length in Distance-Bounding Protocols

Serge Vaudenay, Christos Dimitrakakis, Aikaterini Mitrokotsa

Distance-bounding protocols form a family of challenge-response authentication protocols that have been introduced to thwart relay attacks. They enable a verifier to authenticate and to establish an upper bound on the physical distance to an untrusted prov ...

Oxford University Press2013

Bounded Tamper Resilience: How to go beyond the Algebraic Barrier

Sebastian Faust

Related key attacks (RKAs) are powerful cryptanalytic attacks where an adversary can change the secret key and observe the effect of such changes at the output. The state of the art in RKA security protects against an a-priori unbounded number of certain a ...

2013

Security and Privacy in RFID Systems

Khaled Ouafi

This PhD thesis is concerned with authentication protocols using portable lightweight devices such as RFID tags. these devices have lately gained a significant attention for the diversity of the applications that could benefit form their features, ranging ...

EPFL2012

Fast Key Recovery Attack on ARMADILLO1 and Variants

Serge Vaudenay, Pouyan Sepehrdad, Petr Susil

The ARMADILLO cryptographic primitive is a multi-purpose cryptographic primitive for RFID devices proposed at CHES’10. The main purpose of the primitive is to provide a secure authentication in a challenge-response protocol. It has two versions, named ARMA ...

Springer2011

Publications associées (24)