A tiny public key scheme based on Niederreiter Cryptosystem

Due to the weakness of public key cryptosystems encounter of quantum computers, the need to provide a solution was emerged. The McEliece cryptosystem and its security equivalent, the Niederreiter cryptosystem, which are based on Goppa codes, are one of the solutions, but they are not practical due to their long key length. Several prior attempts to decrease the length of the public key in code-based cryptosystems involved substituting the Goppa code family with other code families. However, these efforts ultimately proved to be insecure. In 2016, the National Institute of Standards and Technology (NIST) called for proposals from around the world to standardize post-quantum cryptography (PQC) schemes to solve this issue. After receiving of various proposals in this field, the Classic McEliece cryptosystem, as well as the Hamming Quasi-Cyclic (HQC) and Bit Flipping Key Encapsulation (BIKE), chosen as code-based encryption category cryptosystems that successfully progressed to the final stage. This article proposes a method for developing a code-based public key cryptography scheme that is both simple and implementable. The proposed scheme has a much shorter public key length compared to the NIST finalist cryptosystems. The key length for the primary parameters of the McEliece cryptosystem (n=1024, k=524, t=50) ranges from 18 to 500 bits. The security of this system is at least as strong as the security of the Niederreiter cryptosystem. The proposed structure is based on the Niederreiter cryptosystem which exhibits a set of highly advantageous properties that make it a suitable candidate for implementation in all extant systems

Principles of Physical Layer Security in Multiuser Wireless Networks: A Survey

This paper provides a comprehensive review of the domain of physical layer security in multiuser wireless networks. The essential premise of physical-layer security is to enable the exchange of confidential messages over a wireless medium in the presence of unauthorized eavesdroppers without relying on higher-layer encryption. This can be achieved primarily in two ways: without the need for a secret key by intelligently designing transmit coding strategies, or by exploiting the wireless communication medium to develop secret keys over public channels. The survey begins with an overview of the foundations dating back to the pioneering work of Shannon and Wyner on information-theoretic security. We then describe the evolution of secure transmission strategies from point-to-point channels to multiple-antenna systems, followed by generalizations to multiuser broadcast, multiple-access, interference, and relay networks. Secret-key generation and establishment protocols based on physical layer mechanisms are subsequently covered. Approaches for secrecy based on channel coding design are then examined, along with a description of inter-disciplinary approaches based on game theory and stochastic geometry. The associated problem of physical-layer message authentication is also introduced briefly. The survey concludes with observations on potential research directions in this area.Comment: 23 pages, 10 figures, 303 refs. arXiv admin note: text overlap with arXiv:1303.1609 by other authors. IEEE Communications Surveys and Tutorials, 201

Bhattacharyya parameter of monomials codes for the Binary Erasure Channel: from pointwise to average reliability

Monomial codes were recently equipped with partial order relations, fact that allowed researchers to discover structural properties and efficient algorithm for constructing polar codes. Here, we refine the existing order relations in the particular case of Binary Erasure Channel. The new order relation takes us closer to the ultimate order relation induced by the pointwise evaluation of the Bhattacharyya parameter of the synthetic channels. The best we can hope for is still a partial order relation. To overcome this issue we appeal to related technique from network theory. Reliability network theory was recently used in the context of polar coding and more generally in connection with decreasing monomial codes. In this article, we investigate how the concept of average reliability is applied for polar codes designed for the binary erasure channel. Instead of minimizing the error probability of the synthetic channels, for a particular value of the erasure parameter p, our codes minimize the average error probability of the synthetic channels. By means of basic network theory results we determine a closed formula for the average reliability of a particular synthetic channel, that recently gain the attention of researchers.Comment: 21 pages, 5 figures, 3 tables. Submitted for possible publicatio

Quantum cryptography: key distribution and beyond

Uniquely among the sciences, quantum cryptography has driven both foundational research as well as practical real-life applications. We review the progress of quantum cryptography in the last decade, covering quantum key distribution and other applications.Comment: It's a review on quantum cryptography and it is not restricted to QK

Wave: A New Code-Based Signature Scheme

preprint IACR disponible sur https://eprint.iacr.org/2018/996/20181022:154324We present here Wave the first "hash-and-sign" code-based signature scheme which strictly follows the GPV strategy [GPV08]. It uses the family of ternary generalized (U, U + V) codes. We prove that Wave achieves existential unforgeability under adaptive chosen message attacks (EUF-CMA) in the random oracle model (ROM) with a tight reduction to two assumptions from coding theory: one is a distinguishing problem that is related to the trapdoor we insert in our scheme, the other one is DOOM, a multiple target version of syndrome decoding. The algorithm produces uniformly distributed signatures through a suitable rejection sampling. Our scheme enjoys efficient signature and verification algorithms. For 128 bits of classical security, signature are 8 thousand bits long and the public key size is slightly smaller than one megabyte. Furthermore, with our current choice of parameters, the rejection rate is limited to one rejection every 3 or 4 signatures

Quantum Cryptography: Key Distribution and Beyond

Uniquely among the sciences, quantum cryptography has driven both foundational research as well as practical real-life applications. We review the progress of quantum cryptography in the last decade, covering quantum key distribution and other applications.Quanta 2017; 6: 1–47

Secure Communications in Next Generation Digital Aeronautical Datalinks

As of 2022, Air Traffic Management (ATM) is gradually digitizing to automate and secure data transmission in civil aviation. New digital data links like the L-band Digital Aeronautical Communications System (LDACS) are being introduced for this purpose. LDACS is a cellular, ground-based digital communications system for flight guidance and safety. Unfortunately, LDACS and many other datalinks in civil aviation lack link layer security measures. This doctoral thesis proposes a cybersecurity architecture for LDACS, developing various security measures to protect user and control data. These include two new authentication and key establishment protocols, along with a novel approach to secure control data of resource-constrained wireless communication systems. Evaluations demonstrate a latency increase of 570 to 620 milliseconds when securely attaching an aircraft to an LDACS cell, along with a 5% to 10% security data overhead. Also, flight trials confirm that Ground-based Augmentation System (GBAS) can be securely transmitted via LDACS with over 99% availability. These security solutions enable future aeronautical applications like 4D-Trajectories, paving the way for a digitized and automated future of civil aviation

Optical ground receivers for satellite based quantum communications

Cryptography has always been a key technology in security, privacy and defence. From ancient Roman times, where messages were sent cyphered with simple encoding techniques, to modern times and the complex security protocols of the Internet. During the last decades, security of information has been assumed, since classical computers do not have the power to break the passwords used every day (if they are generated properly). However, in 1984, a new threat emerged when Peter Shor presented the Shor’s algorithm, an algorithm that could be used in quantum computers to break many of the secure communication protocols nowadays. Current quantum computers are still in their early stages, with not enough qubits to perform this algorithm in reasonable times. However, the threat is present, not future, since the messages that are being sent by important institutions can be stored, and decoded in the future once quantum computers are available. Quantum key distribution (QKD) is one of the solutions proposed for this threat, and the only one mathematically proven to be secure with no assumptions on the eavesdropper power. This optical technology has recently gained interest to be performed with satellite communications, the main reason being the relative ease to deploy a global network in this way. In satellite QKD, the parameter space and available technology to optimise are very big, so there is still a lot of work to be done to understand which is the optimal way to exploit this technology. This dissertation investigates one of these parameters, the encoding scheme. Most satellite QKD systems use polarisation schemes nowadays. This thesis presents for the first time an experimental work of a time-bin encoding scheme for free-space receivers within a full QKD system in the second chapter. The third and fourth chapter explore the advantages of having multi-protocol free-space receivers that can boost the interoperability between systems, polarisation filtering techniques to reduce background. Finally, the last chapter presents a new technology that can help increase communications rates

Understanding Quantum Technologies 2022

Understanding Quantum Technologies 2022 is a creative-commons ebook that provides a unique 360 degrees overview of quantum technologies from science and technology to geopolitical and societal issues. It covers quantum physics history, quantum physics 101, gate-based quantum computing, quantum computing engineering (including quantum error corrections and quantum computing energetics), quantum computing hardware (all qubit types, including quantum annealing and quantum simulation paradigms, history, science, research, implementation and vendors), quantum enabling technologies (cryogenics, control electronics, photonics, components fabs, raw materials), quantum computing algorithms, software development tools and use cases, unconventional computing (potential alternatives to quantum and classical computing), quantum telecommunications and cryptography, quantum sensing, quantum technologies around the world, quantum technologies societal impact and even quantum fake sciences. The main audience are computer science engineers, developers and IT specialists as well as quantum scientists and students who want to acquire a global view of how quantum technologies work, and particularly quantum computing. This version is an extensive update to the 2021 edition published in October 2021.Comment: 1132 pages, 920 figures, Letter forma