Appendix · Application analysis of QKD, RKD, and MKD
This chapter compares QKD, RKD, and MKD in terms of real-world deployment simplicity. It explicitly shifts the focus away from theoretical possibility and toward what can be implemented efficiently and with manageable operational effort. For QKD, the chapter stresses the heavy burden of expensive end devices, encryption units, dedicated connection infrastructure, trusted nodes, satellites for very long distances, and strong dependence on specific manufacturers due to limited interoperability and incomplete standardization.
RKD appears much simpler in this comparison. It requires only compact, inexpensive terminals and encryption units, while communication occurs over radio and does not need special physical infrastructure. Because the devices are cheap and based on mass-market components, vendor changes are less burdensome. Limitations remain for very long distances and satellite-supported scenarios.
MKD is portrayed as structurally simplest. It relies on random number generators, secure storage media, and encryption units, with key exchange occurring through physical transport. A broad market of standardized components supports this model, making vendor replacement relatively easy. The chapter therefore frames MKD as the least infrastructure-intensive of the three, especially when suitable storage media reduce the need for additional hardware.
- Evaluates the methods by deployment simplicity
- Highlights QKD’s infrastructure and vendor burden
- Shows RKD as light and inexpensive but range-limited
- Presents MKD as highly practical and modular
- Emphasizes operational realism over theoretical appeal