QKD

Piller, Ernst; Schölnast, Hubert

doi:10.1007/978-3-032-24764-3_3

Content of this chapter

Chapter 3 · QKD

The QKD chapter is the book’s most extensive technical and practical examination of quantum key distribution. It begins with the security logic of QKD: quantum measurements disturb states, eavesdropping raises error rates, and secure keys emerge only after sifting, error correction, privacy amplification, and authenticated classical communication. It then distinguishes major technology classes such as DV-QKD, CV-QKD, entanglement-based QKD, MDI-QKD, Twin-Field, and DI-QKD.

A major focus lies on implementation reality. The chapter reviews fiber-optic QKD, QKD networks, satellite systems, free-space links, and trusted-node architectures. It shows that real deployments remain heavily dependent on infrastructure, attenuation limits, environmental conditions, and trusted intermediaries. It also reviews device data, user experience, costs, and practical stability.

Crucially, the chapter highlights side-channel and implementation attacks, drawing a strong distinction between theoretical security proofs and real systems. It argues that procurement and operation must account for hardware imperfections, detector attacks, calibration manipulation, software risks, and the enlarged attack surface of trusted-node networks.

Explains QKD protocol flow and assumptions
Compares major QKD technology classes
Reviews fiber, satellite, and free-space deployments
Analyzes trusted-node and KMS dependence
Emphasizes implementation and side-channel risks

Suggested citation

Reference in IEEE style

E. Piller and H. Schölnast, “QKD,” in Data Encryption at the Intersection of Mathematics and Physics: Comparing Physical Methods of Cryptography. Cham, Switzerland: Springer Cham, 2026, doi: 10.1007/978-3-032-24764-3_3.

Reference in ACM style

Ernst Piller and Hubert Schölnast. 2026. QKD. In Data Encryption at the Intersection of Mathematics and Physics: Comparing Physical Methods of Cryptography. Springer Cham, Cham, Switzerland. DOI: 10.1007/978-3-032-24764-3_3

BibTeX entry

@incollection{piller_schoelnast_2026_chapter_3_qkd,
  title     = {QKD},
  author    = {Ernst Piller and Hubert Schölnast},
  booktitle = {Data Encryption at the Intersection of Mathematics and Physics: Comparing Physical Methods of Cryptography},
  publisher = {Springer Cham},
  series    = {SpringerBriefs in Information Security and Cryptography},
  year      = {2026},
  doi       = {10.1007/978-3-032-24764-3_3},
  url       = {https://link.springer.com/chapter/10.1007/978-3-032-24764-3_3},
  language  = {en}
}

RIS entry

TY  - CHAP
TI  - QKD
T2  - Data Encryption at the Intersection of Mathematics and Physics: Comparing Physical Methods of Cryptography
AU  - Piller, Ernst
AU  - Schölnast, Hubert
PY  - 2026
PB  - Springer Cham
T3  - SpringerBriefs in Information Security and Cryptography
DO  - 10.1007/978-3-032-24764-3_3
UR  - https://link.springer.com/chapter/10.1007/978-3-032-24764-3_3
LA  - en
ER  -

CSL JSON entry

{
  "type": "chapter",
  "id": "piller-schoelnast-2026-chapter-3-qkd",
  "title": "QKD",
  "author": [
    {
      "family": "Piller",
      "given": "Ernst"
    },
    {
      "family": "Schölnast",
      "given": "Hubert"
    }
  ],
  "issued": {
    "date-parts": [
      [
        2026,
        6,
        19
      ]
    ]
  },
  "container-title": "Data Encryption at the Intersection of Mathematics and Physics: Comparing Physical Methods of Cryptography",
  "publisher": "Springer Cham",
  "collection-title": "SpringerBriefs in Information Security and Cryptography",
  "DOI": "10.1007/978-3-032-24764-3_3",
  "URL": "https://link.springer.com/chapter/10.1007/978-3-032-24764-3_3",
  "language": "en"
}