Quantum key distribution promises information-theoretic security for key exchange, a guarantee no classical or post-quantum algorithm can match. But QKD also carries real constraints: distance limits, throughput bottlenecks, and hardware costs that make it unsuitable for most defence traffic. This session gives network architects and COMSEC leads a technically honest assessment of where QKD delivers genuine value and where PQC is the better choice.
QKD exploits quantum mechanical properties to distribute encryption keys with security guaranteed by physics rather than computational assumptions. The BB84 protocol with decoy states is the most mature implementation, deployed in metropolitan fibre networks by vendors including ID Quantique and Toshiba. Newer protocols such as CV-QKD eliminate the need for single-photon detectors, while MDI-QKD and twin-field QKD remove entire classes of detector side-channel attacks that have compromised earlier implementations.
For defence organisations, QKD occupies a specific niche. It is appropriate for high-value, short-distance point-to-point links where information-theoretic security justifies the hardware investment: nuclear command and control, embassy-to-capital channels, and SCIF interconnects. It is not a replacement for PQC across general defence IT. Current fibre-based QKD operates reliably to approximately 100 km without quantum repeaters, which remain at least a decade from operational deployment. Satellite QKD extends reach but introduces its own constraints around weather, orbital windows, and ground station security. This session examines both the capabilities and the boundaries.
Deep Dive Session structure with scheduled breaks. Content is configurable to your organisation's technical level and operational environment.
| # | Session | Topics |
|---|---|---|
| 1 | QKD Protocol Foundations Physics-based key distribution versus computational security |
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| 2 | QKD Network Architectures for Defence From point-to-point links to metropolitan and wide-area networks |
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| Break, after 50 min | ||
| 3 | QKD Versus PQC: Trade-off Framework for Defence When each approach fits and when it does not |
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| 4 | Discussion and Next Steps Evaluating QKD for your defence environment |
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Workshops are designed and delivered by QSECDEF in collaboration with sector specialists. All facilitators have direct experience in both quantum technologies and defence systems.
Workshop design and delivery
QSECDEF brings world-leading expertise in post-quantum cryptography, quantum computing strategy, and defence-grade security assessment. Our advisory membership spans 600+ organisations and 1,200+ professionals working at the intersection of quantum technologies and critical infrastructure security.
Domain expertise and operational validation
Defence workshops are co-delivered with sector specialists who bring direct operational experience in defence organisations. This ensures workshop content is grounded in regulatory, operational, and technical realities specific to the sector.
Sessions are configured around your organisation's technical level, operational environment, and regulatory jurisdiction. Get in touch to discuss requirements and schedule a date.
Contact UsQuantum technologies are evolving quickly and new developments emerge regularly. This page was last updated on 15/03/2026. For the most current information about course content and suitability for your organisation, we recommend contacting us directly.
