Stable operation of a Secure QKD system in the real-world setting

Carole A Harper, Michael R. Grimaila, Gerald Baumgartner

Abstract Quantum Key Distribution (QKD) systems combine cryptographic primitives with quantum information theory to produce a theoretic unconditionally secure cryptographic key. However, real‐world implementations of QKD systems are far from ideal and significantly differ from the theoretic models. Because of this real‐world QKD systems require additional practical considerations when implemented to achieve secure operations. In this paper, a content analysis of the published literature is conducted to determine if established security and cryptographic standards are addressed in real world, practical QKD implementations. The research reveals that a majority of real world QKD implementations examined do not take advantage of established security and cryptographic standards. Based upon an analysis of existing industry security and cryptographic standards and best practices, systems architecture guidelines are used to make recommendations for how these standards can and should be applied to establish a practical, secure, QKD system framework.

Antı́a Lamas-Linares, Qin Liu, Ilja Gerhardt +2 more

Hicham Amellal, Abdelmajid Meslouhi, Abderrahim El Allati +1 more

Carole A Harper

Abstract : Quantum Key Distribution (QKD) systems combine cryptographic primitives with quantum information theory to produce a theoretic unconditionally secure cryptographic key. However, real-world implementations of QKD systems are far from ideal and differ significantly from the theoretic model. Because of this, real-world QKD systems require additional practical considerations when implemented to achieve secure operations. In this thesis, a content analysis of the published literature is conducted to determine if established security and cryptographic standards and best practices are addressed in real world, practical QKD implementations. The research reveals that most published, real world QKD implementations do not take advantage of established security and cryptographic standards and best practices. Based upon an analysis of existing security and cryptographic standards and best practices, systems architecture methodology is used to make recommendations as to how these standards can and should be applied to establish a practical, secure, QKD system framework.

Ramona Wolf

Yoann Noblet, Ross J. Donaldson

The secure nature of Quantum Key Distribution (QKD) protocols makes it necessary to ensure that the single photon sources are indistinguishable. Any spectral, temporal or spatial discrepancy between the sources would lead to a breach in the security proofs of the QKD protocols. Traditional, weak-coherent pulse implementations of polarization-based QKD protocols have relied on identical photon sources obtained through tight temperature control and spectral filtering. However, it can be challenging to keep the temperature of the sources stable over time, particularly in a real-world setting, meaning photon sources can become distinguishable. In this work, we present an experimental demonstration of a QKD system capable of achieving spectral indistinguishability, over a 10°C range, using a combination of broadband sources, super-luminescent light emitting diodes (SLEDs), along with a narrow band-pass filter. The temperature stability could be useful in a satellite implementation, where there may be temperature gradients over the payload, particularly on a CubeSat.