Chapter 9 · Concluding remarks and summary
The final chapter consolidates the entire comparison and returns to the central question of what physical key-distribution method fits which application. It first revisits the security objectives. The chapter stresses that provable confidentiality still requires a one-time pad, which in practice makes key volume decisive. On that basis, MKD emerges as the only method that can currently support large-scale OTP use, while QKD and RKD are more realistic as providers of frequently refreshed symmetric keys for conventional encryption such as AES.
The chapter then compares the methods against practical criteria. QKD is portrayed as technologically sophisticated but physically constrained by attenuation, environmental sensitivity, infrastructure dependence, high cost, and trusted-node assumptions. RKD is shown as inexpensive and mobile-friendly but sharply limited in key rate and range. MKD is presented as fundamentally different: strong in key capacity, robustness, and low infrastructure cost, but dependent on disciplined logistics and organizational control.
The overall conclusion is that no universal winner exists. Practical suitability depends on context, risk tolerance, and operational controllability.
- Reassesses confidentiality, integrity, and authenticity
- Compares maturity, range, and key-rate realism
- Weighs cost, infrastructure, and robustness
- Distinguishes physical from organizational risks
- Rejects one-size-fits-all conclusions