Encryption Methods for QKD and RKD and XOR Operation

Piller, Ernst; Schölnast, Hubert

doi:10.1007/978-3-032-24764-3_6

Content of this chapter

Chapter 6 · Encryption Methods for QKD and RKD and XOR Operation

This chapter focuses on how key material from QKD and RKD can be used for encryption when a full one-time pad is impractical. It introduces the XOR operation as the basic mechanism behind OTP-style encryption and explains the strict requirements for perfect confidentiality: truly random key bits, key length at least equal to the plaintext, and no key reuse.

Because QKD and RKD often cannot provide enough fresh key material for large data volumes, the chapter presents new encryption modes designed for these constraints. These methods combine cyclic buffers, hash functions, counters, and XOR operations to extend practical usability while remaining close to mechanisms already present in QKD and RKD post-processing.

The chapter is careful about the trade-off between theoretical purity and operational feasibility. It distinguishes the absolutely secure one-time pad from modes that deliberately relax some constraints to make real deployments possible. The result is a practical bridge between low-rate physical key generation and actual encrypted communication.

Explains XOR and one-time-pad requirements
Connects QKD and RKD key rates to encryption design
Introduces modes based on hashes and cyclic buffers
Distinguishes perfect secrecy from practical variants
Shows why key volume is the limiting design factor

Suggested citation

Reference in IEEE style

E. Piller and H. Schölnast, “Encryption Methods for QKD and RKD and XOR Operation,” 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_6.

Reference in ACM style

Ernst Piller and Hubert Schölnast. 2026. Encryption Methods for QKD and RKD and XOR Operation. 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_6

BibTeX entry

@incollection{piller_schoelnast_2026_chapter_6_encryption_methods_and_xor,
  title     = {Encryption Methods for QKD and RKD and XOR Operation},
  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_6},
  url       = {https://link.springer.com/chapter/10.1007/978-3-032-24764-3_6},
  language  = {en}
}

RIS entry

TY  - CHAP
TI  - Encryption Methods for QKD and RKD and XOR Operation
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_6
UR  - https://link.springer.com/chapter/10.1007/978-3-032-24764-3_6
LA  - en
ER  -

CSL JSON entry

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