Chapter 1 · Introduction
The introduction establishes the conceptual and practical foundation of the book. It argues that traditional cryptography depends on assumptions about computational hardness and unknown future attacks, whereas physical methods seek to anchor security more directly in physical laws. On that basis, the book compares five technology classes: DV-QKD, CV-QKD, entanglement-based QKD, RKD, and MKD.
The chapter explains that the comparison is not a ranking exercise but a structured decision framework. It identifies the intended audience as procurers, experts, and decision-makers facing concrete questions about high-security communication and storage. The authors also clarify that the assessment draws on scientific publications, manufacturer claims, and practical user experience, each with different evidentiary weight.
It further defines the comparison criteria: IT security, market readiness, key rate, range, cost, robustness, mobile suitability, and infrastructure dependence. The chapter highlights the book’s novelty by stressing that RKD and MKD have hardly been covered in book-length form and have not previously been compared systematically with QKD.
- Explains why physical methods deserve attention
- Defines comparison criteria and methodology
- Positions the book as procurement-oriented
- Clarifies source types and comparability limits
- Presents the book’s unique selling point