International Conference on Transparent Optical Networks
INRiM solutions for QKD real-world network implementations
Salvatore Virzì, Alice Meda, Cecilia Clivati, Gianluca Bertaina, Simone Donadello, Marco Gramegna, Ivo Pietro Degiovanni, Marco Genovese, Davide Calonico
Quantum key distribution (QKD) is a technology that allows sharing secret cryptographic keys between two distant users (Alice and Bob), whose intrinsic security is guaranteed by fundamental principles of quantum mechanics. QKD is a mature technology: in Europe, all the 27 EU member states are working in a European Commission initiative (EuroQCI) to design, develop and deploy a quantum communication infrastructure composed by several national networks. For example, in Italy, the Italian Quantum Backbone will be used as a quantum communication testbed within the project QUID, that is in charge of the realization of the Italian part of EuroQCI.
Quantum key distribution (QKD) is a technology that allows sharing secret cryptographic keys between two distant users (Alice and Bob), whose intrinsic security is guaranteed by fundamental principles of quantum mechanics. QKD is a mature technology: in Europe, all the 27 EU member states are working in a European Commission initiative (EuroQCI) to design, develop and deploy a quantum communication infrastructure composed by several national networks. For example, in Italy, the Italian Quantum Backbone will be used as a quantum communication testbed within the project QUID, that is in charge of the realization of the Italian part of EuroQCI.
Quantum key distribution (QKD) is an innovative technology allowing information-theoretically-secure key sharing among distant users relying only on fundamental rules of quantum physics, without assumptions about the computational power of the attacker [1]. Different variants of this technology are making their way into the market since several years and QKD testbeds are under deployment worldwide, for institutional and commercial use. Among the remaining challenges, its integration in existing infrastructure is a vital one, together with the hybridization with different technologies.
Quantum key distribution is an innovative technique to distribute encryption keys without compromise. This paper focuses on the application of this technique to achieve reliable communication in an ever-evolving and increasingly vulnerable environment. Designers of cryptosystems have three basic objectives; designing cryptographic algorithms that adequately scramble the target data, developing strong encryption keys to lock and unlock the algorithm, and securely distributing the keys between communicating devices. The advance of quantum computing technologies threatens to expose the world's most prolific key method overnight. Though quantum computing is not yet a reality, the basic principles have been proven in laboratories. Furthermore, quantum computing has been shown to be especially suited for computations of complex mathematic equations; such as distilling the private keys from the public keys used in public key infrastructures (PKI). In this environment, it's comforting to know that the most advanced technology in the broad field of quantum communications just happens to be a new method of creating and distributing encryption keys. This technology is referred to as quantum key distribution (QKD). QKD technologies shift the current paradigm on two plains. The first is that it uses quantum principles, rather than conventional means, for distributing keys between devices. The quantum principles guarantee the key can not be intercepted during transmission without alerting the users of a compromise. The second shift is derived from the fact that encrypted data can not be intercepted today and decrypted at a later date when the computing power exists to crack the code. This shift is dependant on the use of a combination of QKD and one-time pad. Because of the quantum principles that QKD relies on, when a key is successfully created and shared, it can not be cracked using intercepted data. The keys are derived from a convergence of random operations conducted at the sender and receiver stations. Indeed, neither the sender nor the receiver can determine what the key will be until the entire process is completed. As a piece of our security infrastructure, QKD significantly raises our security posture. This paper explains the application of quantum principals used to enable QKD systems.
Quantum Key Distribution (QKD) networks have emerged the revolutionary technology in ensuring secure communication in the digital age. By utilizing the principles of quantum mechanics, QKD allows two parties to establish a secret key securely, which can subsequently be used for encrypting and decrypting sensitive information. While QKD holds immense promise for enhancing cybersecurity, it also presents several challenges that necessitate further research to achieve its full potential. The research presented here examines the development of QKD networks, their real-world use, as well as the general QKD network architecture and the most recent advancements in QKD network deployments.
Quantum Key Distribution, a fundamental component of quantum secure communication that exploits quantum states and resources for communication protocols, can future-proof the security of digital communications, when if advanced quantum computing systems and mathematical advances render current algorithmic cryptography insecure. A QKD system relies on the integration of quantum physical devices, as quantum sources, quantum channels and quantum detectors, in order to generate a true random (unconditionally secure) cryptographic key between two remote parties connected through a quantum channel. The gap between QKD implemented with ideal and real devices can be exploited to attack real systems, unless appropriate countermeasures are implemented. Characterization of real devices and countermeasure is necessary to guarantee security. Free-space QKD systems can provide secure communication to remote parties of the globe, while QKD systems based on entanglement are intrinsically less vulnerable to attack. Metrology to characterize the optical components of these systems is required. Actually, the “Optical metrology for quantum-enhanced secure telecommunication” Project (MIQC2) is steering the metrological effort for Quantum Cryptography in the European region in order to accelerate the development and commercial uptake of Quantum Key Distribution (QKD) technologies. Aim of the project is the development of traceable measurement techniques, apparatus, and protocols that will underpin the characterisation and validation of the performance and quantum-safe security of such systems, essential steps towards standardization and certification of practical implementations of quantum-based technologies.
ABSTRACT Quantum cryptography has increasingly attracted interest from both industry and academia for its potential in real‐world applications. With advancements in quantum electronics, practical quantum devices are now commercially available and poised for broader adoption. Quantum key distribution (QKD) leverages fundamental principles of quantum mechanics to ensure secure communication, whereas quantum key distribution networks (QKDN) serve as the foundational infrastructure for deploying and scaling these secure systems. This paper examines the design methodologies specific to QKD within QKDN, emphasising both the conceptual framework and the practical challenges inherent in the field. In the pursuit of developing robust QKDN design, several key obstacles, related to the foundational QKD technology, must be addressed. These include decoherence, which affects the stability of quantum states and reduces key generation rates; latency, which disrupts synchronisation throughout the QKD network; and intrinsic quantum noise, an inherent property of quantum systems that primarily limits the overall performance of the QKD network. In addition, the limited communication ranges and the requirement for highly specialised hardware complicate the practical deployment of these networks. This work serves as an introductory guide for researchers entering the field, providing an overview of the fundamental principles of QKD network design and the distinctive routing characteristics inherent to such systems. It outlines the essential steps and considerations for building efficient and resilient QKDN infrastructures, including a discussion of the foundational principles, protocols and existing challenges.
This chapter introduces Quantum Key Distribution (QKD), a key cryptographic technology that employs quantum mechanics to enhance communication security. Central to QKD is its use of quantum principles such as superposition, entanglement, and the no-cloning theorem, which collectively facilitate the generation of secure cryptographic keys. These keys are secure against both traditional cryptographic attacks and those posed by emerging quantum computing technologies. The chapter begins with a detailed introduction to the core concepts of QKD, explaining how it fundamentally differs from classical cryptographic methods by ensuring security based on the laws of physics rather than computational complexity. It traces the historical evolution of QKD, from early theoretical formulations to its current implementations and the development of key protocols like the BB84, which marked a significant milestone in practical QKD applications. As the discussion progresses, the chapter explores various sophisticated QKD protocols, including E91, decoy-state, and Measurement Device Independent (MDI) protocols. Each protocol is analysed for its operational mechanics, security features, and the specific challenges it addresses in protecting data against quantum threats. The technical complexities and requirements for implementing these protocols in real-world scenarios are also examined, showing their potential and limitations for extending secure communication networks. Moreover, the chapter evaluates the practical challenges associated with QKD, such as managing transmission distances, environmental susceptibilities, and the infrastructural demands of deploying quantum networks. It concludes by highlighting the future directions of QKD, underscoring its growing integration into critical global communication infrastructures, and its significant potential to revolutionize data security in the quantum age. This chapter presents the significance of QKD in modern cryptography, demonstrating its evolution from a conceptual framework to a fundamental technology set to counteract the challenges of quantum decryption. Through this approach, the chapter demonstrates the critical role of QKD in fortifying the foundations of secure communications worldwide.