Quantum Information Technologies Journal

Q-Bra and Quantum Technologies for Agricultural Innovation

2026-09-25T13:26:00+02:00

Qubits Brasil, or Q-Bra, is a Brazilian startup that believes in and works towards the use of quantum technologies in agribusiness, aiming to revolutionise precision soil and crop monitoring, optimise resource use, and increase sustainability within 4 years. To establish this advantage for Brazilian agribusiness, it is necessary to overcome challenges related to costs and expertise in quantum technology through investments in research via strategic partnerships, in which Q-Bra has been actively engaged to achieve unprecedented results that justify these initiatives.

PQCWC: Post-Quantum Cryptography Winternitz-Chen Anonymous Scheme

2026-04-03T12:56:32+02:00

As quantum computing technology matures, it poses a threat to the security of mainstream asymmetric cryptographic methods. In response, the National Institute of Standards and Technology released the final version of post-quantum cryptographic (PQC) algorithm standards in August 2024. These post-quantum cryptographic algorithms are primarily based on lattice-based and hash-based cryptography. Therefore, this study proposes the Post-Quantum Cryptography Winternitz-Chen (PQCWC) anonymous scheme, aimed at exploring the design of anonymous schemes based on PQC for future applications in privacy protection. The anonymous scheme designed in this study is mainly built on the Winternitz signature scheme, which can prevent the original public key from being exposed in the certificate. Furthermore, the PQCWC anonymous scheme integrates the butterfly key expansion mechanism, introducing the world’s first hash-based butterfly key expansion mechanism, achieving anonymity for both the registration authority and the certificate authority, thereby fully protecting privacy. In the experimental environment, this study compares various hash algorithms, including Secure Hash Algorithm-1 (SHA-1), the SHA-2 series, the SHA-3 series, and the BLAKE series. The results demonstrate that the proposed anonymous scheme can achieve anonymity without increasing key length, signature length, key generation time, signature generation time, or signature verification time.

Zero Knowledge Arguments for the Post-Quantum Era

2026-07-24T15:00:16+02:00

The approaching threat of quantum computing to conventional cryptography underscores the urgent need to reassess information security and develop practical quantum-safe primitives. In this paper, we present concrete implementations of Zero-Knowledge Arguments (ZKAs), analogous to but distinct from traditional $Σ$ -protocols. Our implementation, termed the Cryptographic Primitive Argument (CPA), can be realized securely using any post-quantum Key Exchange Mechanism (KEM) and Digital Signature (DS) scheme. We describe two variants: one with dynamic public key encapsulation (CPA-DE) and another that is non-interactive (CPA-NI). We further detail efficient, NIST-standard-compliant CPAs instantiated with ML-KEM and ML-DSA, and provide a comparison with a post-quantum $Σ$ -protocol. The lightweight and modular nature of our CPAs makes them suitable for a wide range of applications, including quantum-secure authentication, blockchain systems, and digital currencies.

Quantum Technologies and NATO: Securing the Alliance’s Technological Edge in an Era of Strategic Competition

2026-07-29T16:47:07+02:00

Quantum technologies are rapidly moving from scientific research into the arenas of commercialisation and strategic competition, with significant implications for defence and security. While their full military impact may unfold over time, developments in quantum sensing, computing, and communications are already shaping national strategies, industrial ecosystems, and future capability planning. The growing competition among major technological powers highlights the need to act on both the opportunities and risks associated with quantum technologies.

Quantum technologies have the potential to enhance military capabilities across domains, from resilient positioning, navigation, and timing to advanced sensing, computing, and secure communications. At the same time, they introduce new vulnerabilities, including risks to current cryptographic systems, supply chains, and technological dependencies. For NATO, the debate is therefore no longer whether quantum technologies matter, but how quickly the Alliance can adopt, operationalise, and secure them before strategic competitors gain asymmetric advantages.

This article argues that NATO must pursue a two-track approach: first, fostering quantum innovation, experimentation, and operational adoption across the Alliance; and second, protecting its technological edge, supply chains, critical infrastructure, and security interests against emerging quantum-enabled threats. Achieving a quantum-ready Alliance will require close cooperation among Allies, industry, academia, and NATO entities to translate technological progress into secure and operationally relevant capabilities.

Translating Post-Quantum Cryptography Roadmaps into an Actionable SME Migration Framework

2026-07-21T03:42:55+02:00

Small and medium-sized enterprises (SMEs) face the same quantum-era cryptographic exposure as large organisations, but they often lack the specialised security teams, governance maturity, asset visibility, and implementation budgets assumed by most post-quantum cryptography (PQC) roadmaps developed for governments, public institutions, and large enterprises. This paper addresses this challenge by adopting a structured research process to develop an evidence-based, SME-specific PQC migration framework that translates practical insights from existing roadmaps, standards, practitioner publications, and academic studies into structured actionable guidance. The framework also identifies activities that extend beyond typical SME capabilities into the operational domain of larger enterprises. The research study uses a human-supervised, large-language-model (LLM)-assisted text-analytics workflow based on a comprehensive multi-criteria decision analysis (MCDA). An initial corpus of 52 documents was evaluated for SME relevance, practical usefulness, clarity, and coverage. Seventeen high-value documents were selected for deeper analysis, producing 556 source-linked migration insights. These insights were validated, consolidated, and prioritised into 73 decision-oriented actions organised across four phases: Prepare, Assess, Implement, and Govern. The results show that PQC migration is not simply an algorithm-replacement exercise; it is an organisational transformation process requiring governance, cryptographic visibility, vendor coordination, phased implementation, and continuous monitoring. The contribution is both practical and methodological: a lifecycle-based migration model for SMEs and larger enterprises, and a replicable evidence-to-action analytical process for converting dispersed technical guidance into context-specific organisational action.

The Importance of Standards in the Adoption of Quantum-Resistant Technologies

2026-08-12T15:26:51+02:00

The emergence of large-scale quantum computing poses a concrete threat to the public-key cryptographic algorithms widely used in today’s information technology systems. Over the past three decades, post-quantum cryptography (PQC) and quantum key distribution (QKD) have been proposed to protect against this threat. This article traces the formation and output of research and standards organizations that made these technologies viable for deployment, with particular attention to ETSI, and the NIST Post-Quantum Cryptography standardisation initiative. The article argues that necessity and standardisation, rather than any single technical contribution, was the decisive factor in taking this research from academia and laboratories into an interoperable ecosystem now reaching production deployment. The article further conjectures on reasons why PQC will see much broader adoption than QKD based on some basic principles of adoption of standardized technologies.

Migration to Quantum Safe Blockchains: A Compact Architecture Using MPPK Key Encapsulation Mechanism and HPPK Digital Signatures

2026-07-30T04:34:03+02:00

The advent of quantum computing threatens the public-key cryptography that underlies modern blockchains, including ECDSA, Ed25519, and ECDH. Although NIST has standardized lattice-based schemes (ML-KEM and ML-DSA) as quantum-safe standards, their large key and signature sizes (several kilobytes each) pose scalability challenges for blockchains. We propose a quantum-safe blockchain architecture based entirely on multivariate polynomial cryptography, specifically the MPPK KEM key encapsulation mechanism and HPPK DS digital signature scheme. Using their linear configuration, MPPK KEM, and HPPK DS produce compact public keys (196-536 bytes) and signatures (144-272 bytes) – considerably smaller than ML-DSA’s 2–3 KB. We present a blockchain design that natively integrates these primitives. We analyze its security under classical and quantum adversarial models. We estimate transaction throughput and block capacity. Compared to lattice-based alternatives, our projections suggest that compact representations significantly improve transaction throughput and reduce on-chain storage. This work aims to contribute to ongoing quantum-safe standardization efforts, including those within ETSI, by demonstrating a concrete architectural pathway.