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Appendix · Further research needs for QKD, RKD, MKD

From the book: Data Encryption at the Intersection of Mathematics and Physics – Comparing Physical Methods of Cryptography

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Appendix · Further research needs for QKD, RKD, MKD

This chapter looks forward rather than backward. It asks where further research is most urgently needed for QKD, RKD, and MKD and does so from a broad state-of-the-art perspective. The chapter makes clear that QKD has by far the largest research burden. Needed advances include higher key rates over longer distances, lower costs, stronger defenses against side-channel attacks, improved component stability, better trusted-node concepts, satellite integration, and much more mature standardization. Entanglement-based QKD is presented as especially important because of its physical elegance and integrated randomness, but also as especially demanding.

RKD is described as a simpler and more mature technological field with a broad publication base and readily available components. Its key challenges lie in improved final-key derivation and in creating useful channel dynamics when natural motion is absent.

MKD is portrayed as the simplest case from a research perspective. Here, the main technical need concerns faster and more easily verifiable non-deterministic random number generators. Storage media, logistics, and standardization are also mentioned, but the chapter suggests that many enabling technologies already exist and that progress is comparatively straightforward.

  • Identifies distinct research profiles for all three methods
  • Assigns the largest open problems to QKD
  • Sees RKD as mature but still improvable
  • Focuses MKD research on randomness and logistics
  • Highlights standardization as a cross-cutting theme

Suggested citation

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Show BibTeX placeholder 
@incollection{piller_schoelnast_physcrypto_ch1,
  title     = {Introduction},
  author    = {Piller, Ernst and Sch\"olnast, Hubert},
  booktitle = {Data Encryption at the Intersection of Mathematics and Physics},
  publisher = {Springer},
  year      = {2026},
  note      = {Open Access}
}