A post-quantum cryptographic framework for high-level security protocols in 6G

Sixth Generation (6G) networks will support critical, latency-sensitive, and large-scale services, making them attractive targets for quantum-capable adversaries. To address this, the paper proposes a conceptual Post-Quantum Cryptography (PQC) framework for high-level security protocols in 6G, including Transport Layer Security (TLS) 1.3, Internet Key Exchange version 2 (IKEv2), Secure Shell (SSH), Message Queuing Telemetry Transport (MQTT), and Constrained Application Protocol (CoAP), using security-by-design principles, hybrid classical–post-quantum migration, and optimization for resource-constrained and heterogeneous environments. The framework defines key metrics such as handshake latency, computational
and memory overhead, energy consumption, interoperability, and resistance to quantum and classical attacks, and analyzes risks introduced by hybrid protocol complexity, side channels, and implementation flaws. The framework is illustrated via a reference hybrid TLS 1.3 design using National Institute of Standards and Technology (NIST)-standardized Module-Lattice-Based Key-Encapsulation Mechanism (ML-KEM) and Module-Lattice-Based Digital Signature Algorithm (ML-DSA) and an evaluation methodology based on Open Secure Sockets Layer (OpenSSL)/liboqs, outlining how future prototypes can measure latency, bandwidth, and computational overhead under Ultra-Reliable Low-Latency Communication (URLLC) and Massive Machine-Type Communications (mMTC) constraints. By combining requirements analysis, design patterns, and evaluation methodology, this work supports quantum-safe 6G infrastructure with scalable, reliable, and long-term secure deployment, providing a blueprint for future empirical validation rather than reporting completed measurements.