Abstract Quantum‐based technologies will provide system engineers with new capabilities for securing data communications. The UK AirQKD project has implemented a Free‐Space Optical Quantum Key Distribution (QKD) system to enable the continuous generation of symmetric encryption keys. One of the use cases for the generated keys is to secure Vehicle‐to‐Everything (V2X) communications. V2X applications would benefit from the certificate‐free security provided by QKD for a post‐quantum society. How FSO‐QKD could integrate into a V2X architecture is examined. An overview of V2X is provided with the role that FSO‐QKD could secure V2X data though some obstacles exist. One of the issues with 6G communications is the potential line‐of‐sight (LOS) considerations between the V2X devices. The modelling required for LOS is examined to analyse the outage performance of the building to infrastructure links in the 6G architecture. The results from the model show that further work is required if 6G LOS communications are going to be relied upon for future safety‐critical V2X applications.
Abstract Quantum‐based technologies will provide system engineers with new capabilities for securing data communications. The UK AirQKD project has implemented a Free‐Space Optical Quantum Key Distribution (QKD) system to enable the continuous generation of symmetric encryption keys. One of the use cases for the generated keys is to secure Vehicle‐to‐Everything (V2X) communications. V2X applications would benefit from the certificate‐free security provided by QKD for a post‐quantum society. How FSO‐QKD could integrate into a V2X architecture is examined. An overview of V2X is provided with the role that FSO‐QKD could secure V2X data though some obstacles exist. One of the issues with 6G communications is the potential line‐of‐sight (LOS) considerations between the V2X devices. The modelling required for LOS is examined to analyse the outage performance of the building to infrastructure links in the 6G architecture. The results from the model show that further work is required if 6G LOS communications are going to be relied upon for future safety‐critical V2X applications.
We provide a practical implementation of a free space optical quantum key distribution (FSO-QKD) system within a vehicle-to-infrastructure (V2I) application developed under the Innovate UK AirQKD project. The FSO-QKD system provides the quantum secure encryption keys that serve as the foundation for secure communications throughout the V2I application to address known concerns over V2I security. This document includes summaries of the quantum key generation process and the deployed V2I technology. Subsequently, a high-level view of the system design, the practical experiment, and its execution are presented. Multiple AirQKD project partners developed technologies ranging from semiconductors and hardware to security protocols and software, to enable the QKD-secured V2I system. The developed technology includes a novel zero-trust security protocol used to protect the V2I communications, ensuring that spoofed V2I messages from a compromised device are not accepted by the system.
Next generation communications will require the exploration of alternatives to existing technologies to enable end-to-end connections for secure data exchange. 5G presents advanced connectivity opportunities even for remote rural areas. However, existing 5G platforms will benefit from complementary methods to enhance network capabilities and fulfill trust requirements. Due to high throughput data links, high-beam directivity, and energy efficiency, free-space optics (FSO) is an alternative solution with the potential to deliver high-performance and efficient security. FSO systems can be improved by adding quantum-key-distribution security to overcome advances in quantum computation. However, practical FSO quantum key distribution (FSO-QKD) requires simultaneous engineering of many elements. To oversee this requirement, the Innovate-UK project addresses the possibility of metropolitan-scale “last-mile” quantum secure connectivity through the use of free-space QKD links to support real-life use cases. In this article, we outline the design, development, and deployment of these elements within the AirQKD project.
With ever increasing requirements for security and capacity, Quantum Key Distribution (QKD) over Free-space Optics (FSO) offers an alternative solution for 5G and beyond. The Innovate-UK AirQKD project addresses the possibility of metropolitan-scale ‘last-mile’ quantum secure connectivity through FSO-QKD. However, the practical implementation of FSO-QKD faces a multitude of engineering problems across software, hardware, and security. In this paper we examine the challenges of system architecture, integration, QKD transmission via FSO, and the post-processing of keys. We illustrate the design of an integrated system architecture with quantum and classical domains combining advanced FSO-QKD hardware and software, demonstrating its functionality for transmission, post-processing, network control and key management. Moreover, we show the results of an FSO-QKD link over 135 m at BT's Adastral Park in Suffolk, UK, and demonstrate a photon count rate up to 585 kcps over the channel loss of 15.9 dB, with 12 kHz background noise. The post-processing results show the potential key generation capability of the system and verify the feasibility of the successful transmission of orthogonal polarization states.
As the demand for better security and higher capacity grows, quantum key distribution (QKD) using free-space optics (FSO) presents an innovative solution for 5G networks and beyond. The Innovate-UK AirQKD project explores how FSO–QKD could enable quantum-secure connections at a metropolitan scale, focusing on the critical “last-mile” of connectivity. However, implementing FSO–QKD in the real world brings several engineering challenges, spanning software, hardware, system integration, and security. This paper dives into the complexities of system architecture and integration, QKD transmission over FSO, and the post-processing of keys. We showcase a cohesive system design that blends the quantum and classical domains, incorporating cutting-edge FSO–QKD hardware and software. The system’s functionality is demonstrated for key processes such as transmission, post-processing, network control, and key management. As a case study, we tested an FSO–QKD link over 135 m at BT’s Adastral Park in Suffolk, UK. The setup achieved a photon count rate of up to 585 kcps through a channel with 15.9 dB of loss and 12 kHz of background noise, resulting in a security key rate (SKR) of up to 84.3 kbps using two detectors. We also conducted simulations to estimate the SKR and compared them with the experimental results. Both approaches confirm the system’s ability to generate keys and successfully transmit orthogonal polarization states, highlighting its potential for practical application.
Abstract The evolution of Connected and Autonomous Vehicles (CAVs) promises improvements in our travel experience and the potential to enhance road safety and reduce environmental impact. This will be utilising highly diverse traffic environments that enable several advanced mobility applications. A secure, efficient, reliable, and resilient communications infrastructure is required to support developments in these CAV systems. Next generation of telecommunication networks will seamlessly integrate terrestrial, satellite, and airborne networks into a single wireless system satisfying the requirements of trustworthy future transport systems. Given the increasing importance of CAVs, coupled with their attractiveness as a cyber‐attack for threat agents (e.g., disruption of transportation systems by nation states), security is paramount. Future communications systems offer an opportunity to integrate Quantum Key Distribution (QKD) into vehicular environments, protecting against advances in quantum computation that render many of the classical algorithms that underpin Public Key Infrastructure obsolete. This paper proposes a method for the integration of QKD in V2I networks to enable secure data communication. Quantum Key Distribution is used in the end‐to‐end path of vehicle‐to‐infrastructure (V2I) networks. Furthermore, an overarching Software‐Defined Network, with integrated QKD, is introduced. We have investigated the security performance of QKD in a V2I network over an urban environment.
Sixth-generation (6G) networks offer unprecedented ultra-reliability, capacity, and low-latency communication. Nevertheless, the same developments also pose security threats to complex communication infrastructures that may be resistant to traditional cryptographic tools, especially in the context of quantum computing. Quantum Key Distribution (QKD) is an innovative technique for achieving unconditional security that leverages quantum-mechanical principles to share cryptographic keys securely. This paper discusses how QKD can be integrated into 6G and beyond networks and used to ensure the confidentiality and integrity of data across applications such as autonomous systems, the Internet of Things (IoT), and smart city infrastructure. This paper explores the architecture of QKD-based 6G communication, key-generation systems, and quantum-resistant network layers. It also examines scalability, synchronization, and hardware implementation, and suggests possible hybrid approaches for integrating classical and quantum security protocols. The results imply that the idea of QKD may become the foundation of safeguarded communication systems in the future, ensuring resilience against attacks in the quantum era and enabling individuals to trust the next generation of wireless.