A critical analysis of deployed use cases for quantum key distribution and comparison with post-quantum cryptography

Area of Science:

• Quantum Information Science
• Cybersecurity
• Applied Cryptography

Background:

• Traditional public-key cryptosystems face obsolescence due to advancing quantum computing capabilities.
• Quantum Key Distribution (QKD) emerges as a promising solution for future-proof communication security.
• Post-Quantum Cryptography (PQC) presents an alternative algorithmic approach to quantum-resistant security.

Purpose of the Study:

• To conduct a comprehensive security evaluation of Quantum Key Distribution (QKD) solutions.
• To analyze real-world use cases and assess the advantages of deploying QKD.
• To compare the suitability of QKD against Post-Quantum Cryptography (PQC) for various scenarios.

Main Methods:

• Systematic review of academic literature and industry reports on QKD use cases.
• In-depth security assessment of identified QKD applications.
• Comparative analysis of QKD and PQC based on implementation complexity, scalability, and long-term security.

Main Results:

• Identified specific use cases where QKD offers significant security advantages.
• Evaluated the practical security and performance of current QKD implementations.
• Determined scenarios where QKD is more or less suitable compared to PQC.

Conclusions:

• QKD is a viable technology for specific applications requiring high security against quantum threats.
• The choice between QKD and PQC depends critically on the use case requirements and constraints.
• Findings provide guidance for decision-makers on the strategic deployment of QKD in future cryptographic infrastructures.