Multipartite quantum key distribution boosts secure group communication
Multipartite FSO/QKD with N-GHZ States for Scalable Secure Group Key Distribution
Networking and Internet Architecture
Summary
Group communication in future wireless networks needs very secure ways to share encryption keys, especially against new types of computers that can break old codes. The authors propose a method using a special kind of quantum technology, involving multiple parties sharing a certain quantum state, to safely create group keys through light signals from high platforms. They tested their approach using simulations that include real-world problems like signal distortions and found it generates secure keys faster and with less delay than older methods. This approach could help protect large group communications in advanced wireless systems.
What this means in practice
- •For network security engineers: Establish secure group keys for large-scale 6G networks to defend against quantum-enabled eavesdropping using multipartite QKD over free-space optical channels.
- •For satellite communication operators: Implement group key management in high-altitude platforms supporting free-space optical links to improve secure group communications for airborne or satellite systems.
Authors
Yuma Kaminaga, Hoang D. Le, Cuong T. Nguyen, Anh T. Pham
Abstract
The emergence of sixth-generation (6G) wireless networks is driving the need for secure group key generation mechanisms resilient to quantum-computing attacks. Conventional quantum key distribution (QKD) protocols are designed for point-to-point communication and are therefore not directly applicable to group key establishment. To address this limitation, this paper proposes a scalable High-Altitude Platform (HAP)-assisted multipartite QKD network architecture that integrates $N$-GHZ-state protocols with a Time Division Multiple Access (TDMA) scheme over free-space optical (FSO) channels. The performance of the proposed system is evaluated using a Qiskit-based simulation framework that incorporates realistic physical-layer impairments of FSO links. Simulation results demonstrate that the proposed architecture significantly improves the group secret key rate (SKR) compared to conventional bipartite approaches, while effectively reducing overall network execution delay. In addition, the analysis reveals the impact of channel impairments and provides practical design insights, such as optimal beam-waist control. The proposed framework demonstrates the potential of HAP-assisted multipartite QKD as an effective security solution for future large-scale 6G wireless networks supporting secure group communications.