Benchmarking hybrid quantum-safe cryptography over real-world infrastructures

Advances in quantum computing pose a significant threat to the widely used Public Key Infrastructure (PKI). The two leading technologies to address this challenge are Post-Quantum Cryptography and Quantum Key Distribution. A promising approach is the hybridization of these technologies -- combining their respective strengths while mitigating their limitations -- and integrating them with the cryptographic mechanisms used today to enhance crypto-agility and facilitate transitioning to a quantum-safe infrastructure. However, changing current network protocols to quantum-safe alternatives is not just a matter of security: their efficiency and scalability must also be demonstrated within real-world telecommunications infrastructures to ensure their practical adoption. In this work, we present the first long-running test with detailed measurements of a suite of hybrid quantum-safe protocols that integrate classical cryptography, PQC, and QKD within a production environment (MadQCI). Using standardized protocols and interfaces and employing Transport Layer Security (TLS) as the base protocol for real-world comparison, this study demonstrates the efficiency and scalability of the proposed solution in deployed heterogeneous networks. These results mark a significant step towards broad adoption and clarify future standardization of quantum-safe hybrid protocols in next-generation telecommunications networks.