Quantum-safe hybrid key exchanges with KEM-based authentication

Area of Science:

• Cryptography and Network Security
• Post-Quantum Cryptography
• Applied Cryptography

Background:

• Authenticated Key Exchange (AKE) is crucial for secure digital infrastructures.
• The Muckle+ protocol offers hybrid AKE for large quantum-safe networks but relies on less efficient post-quantum signatures.
• Efficiency of post-quantum signatures hinders scalability in large networks.

Purpose of the Study:

• To propose Muckle#, a novel hybrid AKE protocol for enhanced efficiency in large quantum-safe networks.
• To address the efficiency limitations of post-quantum signatures in existing HAKE protocols.
• To explore KEM-based implicit authentication for HAKE, inspired by TLS advancements.

Main Methods:

• Developed Muckle#, a new HAKE protocol utilizing post-quantum Key Encapsulation Mechanisms (KEMs) for authentication.
• Adapted KEM-based authentication principles from Transport Layer Security (TLS) protocols like KEMTLS.
• Introduced novel proof techniques to analyze the security and functionality of the KEM-based approach.
• Implemented a proof-of-concept to demonstrate the protocol's practicality.

Main Results:

• Muckle# achieves improved efficiency in hybrid authenticated key exchange by leveraging post-quantum KEMs.
• The KEM-based authentication results in a modified message flow compared to signature-based methods.
• A practical proof-of-concept validates the feasibility of Muckle#.

Conclusions:

• Muckle# presents a more efficient alternative for hybrid authenticated key exchange in large quantum-safe networks.
• The use of post-quantum KEMs for implicit authentication offers a viable path for scalable HAKE.
• This work demonstrates the practicality and potential of KEM-based authentication in HAKE protocols.