The Ephemeral Diffie-Hellman over COSE (EDHOC) is a compact and lightweight key establishment protocol for constrained scenarios that provides end-to-end application layer security context. However, because of the vulnerability of the discrete logarithm problem to Shor’s algorithm, a quantum resistant replacement for Diffie-Hellman is required. This paper proposes an architecture to transform EDHOC into a quantum-resistant protocol, with an open-source implementation supporting various Post Quantum Cryptography (PQC) schemes from the National Institute of Standards and Technology (NIST) PQC standardization process. Necessary modifications to EDHOC are analyzed, integrating PQC Key Encapsulation Mechanisms (KEMs) and PQC digital signatures in a complete Post-Quantum (PQ) version of the EDHOC protocol (PQ-EDHOC). PQC operations often involve complex computations and require larger byte sizes, which can challenge resource-constrained devices designed for lightweight operation in constrained network environments. To evaluate the applicability of various PQC schemes in a realistic PQ EDHOC environment, various PQC KEM and Digital Signature combinations are assessed for execution time, energy consumption, memory usage, and network performance on an nRF52840 ARM Cortex-M4 platform with a 6LoWPAN (IPv6 over Low-Power Wireless Personal Area Networks) over BLE (Bluetooth LowEnergy) network. Results indicate that NIST standardized ML-KEM emerges as the only suitable KEM choice for resource-constrained environments, while promising new signature schemes, like HAWK, show significant performance improvement over the NIST standardized ML-DSA and selected for standardization FALCON.
The Ephemeral Diffie-Hellman over COSE (EDHOC) is a compact and lightweight key establishment protocol for constrained scenarios that provides end-to-end application layer security context. However, because of the vulnerability of the discrete logarithm problem to Shor’s algorithm, a quantum resistant replacement for Diffie-Hellman is required. This paper proposes an architecture to transform EDHOC into a quantum-resistant protocol, with an open-source implementation supporting various Post Quantum Cryptography (PQC) schemes from the National Institute of Standards and Technology (NIST) PQC standardization process. Necessary modifications to EDHOC are analyzed, integrating PQC Key Encapsulation Mechanisms (KEMs) and PQC digital signatures in a complete Post-Quantum (PQ) version of the EDHOC protocol (PQ-EDHOC). PQC operations often involve complex computations and require larger byte sizes, which can challenge resource-constrained devices designed for lightweight operation in constrained network environments. To evaluate the applicability of various PQC schemes in a realistic PQ EDHOC environment, various PQC KEM and Digital Signature combinations are assessed for execution time, energy consumption, memory usage, and network performance on an nRF52840 ARM Cortex-M4 platform with a 6LoWPAN (IPv6 over Low-Power Wireless Personal Area Networks) over BLE (Bluetooth LowEnergy) network. Results indicate that NIST standardized ML-KEM emerges as the only suitable KEM choice for resource-constrained environments, while promising new signature schemes, like HAWK, show significant performance improvement over the NIST standardized ML-DSA and selected for standardization FALCON.
Several lightweight protocols are being developed to secure communication in resource-constrained environments. Ephemeral Diffie-Hellman over COSE (EDHOC) plays a key role in this lightweight protocol family by managing the key establishment process. However, due to the vulnerability of the discrete logarithm problem to Shor’s algorithm, a quantum-resistant replacement for Diffie-Hellman is required. This work examines the quantum-resistant transition of EDHOC, focusing on its multiple authentication methods as a step toward enabling robust post-quantum security for IoT devices. A novel authentication method for EDHOC is introduced, utilizing Key Encapsulation Mechanisms (KEMs) as a replacement for the static Diffie-Hellman (DH) authentication method, providing a post-quantum signature-free alternative. Among existing post-quantum algorithms for both KEMs and signatures, the NIST-standardized ML-KEM offers the fastest implementation at the lowest memory cost, both of which are crucial for resource-constrained devices. While compatible with various post-quantum KEMs, the method can exploit the computational efficiency of ML-KEM to bring a PQ Signature-free EDHOC to highly constrained devices, providing the same security guarantees as classical EDHOC once the handshake is complete. Additionally, an efficient three-message handshake KEM-based EDHOC Initiator Known Responder (IKR) variant is proposed for environments with pre-established peer awareness.
Traditional public-key cryptography algorithms, such as Elliptic Curve Diffie-Hellman (ECDH), are vulnerable to quantum computing attacks. More critically, security protocols based on these algorithms are exposed to the “Harvest Now, Decrypt Later” threat, an ongoing risk that emphasizes the urgency of transitioning to post-quantum cryptography. This transition presents a significant challenge for lightweight security protocols, such as Ephemeral Diffie-Hellman over COSE (EDHOC), which are designed for IoT environments. To address this, a PQ/T hybrid key exchange construction for EDHOC is proposed, combining post-quantum mechanisms alongside traditional algorithms to mitigate future quantum threats while remaining secure against current threats using well-established classical cryptography. The scheme is evaluated on a CortexM4 processor, demonstrating the best performance with ML-KEM-512, with a slight increase in processing time, limited RAM overhead, and a roughly sevenfold increase in message size. Despite these trade-offs, the hybrid construction remains practical and represents a viable option for enhancing EDHOC security in anticipation of the post-quantum era in constrained environments.
The emergence of large-scale quantum computing presents an imminent threat to contemporary public-key cryptosystems, with quantum algorithms such as Shor’s algorithm capable of efficiently breaking RSA and elliptic curve cryptography (ECC). This vulnerability has catalyzed accelerated standardization efforts for post-quantum cryptography (PQC) by the U.S. National Institute of Standards and Technology (NIST) and global security stakeholders. While theoretical security analysis of these quantum-resistant algorithms has advanced considerably, comprehensive real-world performance benchmarks spanning diverse computing environments—from high-performance cloud infrastructure to severely resource-constrained IoT devices—remain insufficient for informed deployment planning. This paper presents the most extensive cross-platform empirical evaluation to date of NIST-selected PQC algorithms, including CRYSTALS-Kyber and NTRU for key encapsulation mechanisms (KEMs), alongside BIKE as a code-based alternative, and CRYSTALS-Dilithium and Falcon for digital signatures. Our systematic benchmarking framework measures computational latency, memory utilization, key sizes, and protocol overhead across multiple security levels (NIST Levels 1, 3, and 5) in three distinct hardware environments and various network conditions. Results demonstrate that contemporary server architectures can implement these algorithms with negligible performance impact (<5% additional latency), making immediate adoption feasible for cloud services. In contrast, resource-constrained devices experience more significant overhead, with computational demands varying by up to 12× between algorithms at equivalent security levels, highlighting the importance of algorithm selection for edge deployments. Beyond standalone algorithm performance, we analyze integration challenges within existing security protocols, revealing that naive implementation of PQC in TLS 1.3 can increase handshake size by up to 7× compared to classical approaches. To address this, we propose and evaluate three optimization strategies that reduce bandwidth requirements by 40–60% without compromising security guarantees. Our investigation further encompasses memory-constrained implementation techniques, side-channel resistance measures, and hybrid classical-quantum approaches for transitional deployments. Based on these comprehensive findings, we present a risk-based migration framework and algorithm selection guidelines tailored to specific use cases, including financial transactions, secure firmware updates, vehicle-to-infrastructure communications, and IoT fleet management. This practical roadmap enables organizations to strategically prioritize systems for quantum-resistant upgrades based on data sensitivity, resource constraints, and technical feasibility. Our results conclusively demonstrate that PQC is deployment-ready for most applications, provided that implementations are carefully optimized for the specific performance characteristics and security requirements of target environments. We also identify several remaining research challenges for the community, including further optimization for ultra-constrained devices, standardization of hybrid schemes, and hardware acceleration opportunities.
The advent of quantum computing poses significant threats to classical public-key cryptographic systems such as RSA and Elliptic Curve Cryptography, necessitating quantum-safe migration paths for Internet of Things (IoT) communication. The Ephemeral Diffie-Hellman Over COSE (EDHOC) protocol provides lightweight authenticated key exchange for resource-constrained IoT devices but lacks quantum-safe security and formally verified implementations. This thesis introduces KEMEDHOC, a KEM-based, signature-free, post-quantum variant of EDHOC that achieves mutual authentication through optimized integration of Key Encapsulation Mechanisms (KEMs). Compared to the direct adaptation, KEMEDHOC reduces noticeably message size (by over \textbf{33\%}) and handshake time (by \textbf{15\%}), while maintaining comparable security levels. Formal verification, at design-level, using ProVerif confirms that KEMEDHOC preserve all core EDHOC security properties, including mutual authentication, confidentiality, and forward secrecy. Verified implementations (EDHOC* and KEMEDHOC*) developed in F* and Low* ensure functional correctness, memory safety, and timing constant-time behavior, down to verified C code through KaRaMel compiler. Overall, this thesis delivers the first end-to-end formally verified post-quantum variant of EDHOC, demonstrating that formal assurance and post-quantum security can be obtained efficiently in lightweight key exchange protocols.
Post-quantum (PQ) cryptographic algorithms are currently being developed to be able to resist attacks by quantum computers. The practical use of these algorithms for securing networks will depend on their computational and communication efficiency. In particular, this is critical for the security of wireless communications within the context of consumer IoT devices that may have limited computational power and depend on a constrained wireless bandwidth. To this end, there is a need to evaluate the performance of widely used application layer security standards such as transport layer security (TLS) to understand the use of the existing PQ algorithms that are being evaluated by NIST as a replacement to the current cryptographic algorithms. This paper focuses on two widely used IoT standards Bluetooth Low Energy (BLE) and WiFi to find out the optimal performing PQ algorithm for their security when used in end-to-end connections over the Internet. By implementing the capability for IP over BLE and all options of TLS connection establishment, we developed a client-server IoT testbed to measure the efficiency of PQ key encapsulation mechanisms (KEMs) and PQ digital signature algorithms. The test results showed that Kyber512 is the ideal KEM while Falcon-512 and Dilithium2 are the best signatures for BLE and WiFi devices. Based on this outcome, we developed a mechanism for IoT devices with multiple communication interfaces, that dynamically chooses a PQ KEM algorithm based on the MAC layer protocol being used at the time.
The security of state-of-the-art Bluetooth pairing relies on Elliptic Curve Diffie–Hellman (ECDH), which is vulnerable to quantum attacks. However, the feasibility of integrating standardized Post-Quantum Cryptographic (PQC) primitives into the controller-level Bluetooth Classic (BC) protocol stack remains an open question. This paper presents the first comprehensive evaluation of integrating a post-quantum secure key exchange for BC pairing. We analyze the impact of replacing the existing ECDH-based key establishment with NIST-standardized PQC Key Encapsulation Mechanisms (KEMs), focusing on protocol-level packetization, over-the-air transmission overhead, and execution performance in constrained hardware. Using BC’s Link Manager Protocol (LMP) and DM1 packet structure, we quantify Public Parameter Transmission (PPT) latency for classical and post-quantum schemes. We further benchmark ECDH and ML-KEM implementations on an ARM Cortex-M4 microcontroller with characteristics comparable to those of constrained Bluetooth controllers. Our results show that ML-KEM is computationally feasible on such hardware, often matching or outperforming classical ECDH in execution time. However, PQC significantly increases over-the-air overhead. Under ML-KEM, PPT accounts for 60–75% of total key exchange latency, compared to less than 10% for ECDH. Code-based schemes such as HQC are shown to be impractical due to excessive memory and transmission requirements under provided hardware constraints. These findings indicate that the primary obstacle to post-quantum Bluetooth pairing is not computation but wireless packetization, reliability, and energy consumption; facilitating a safe and efficient quantum-secure migration of resource-constrained wireless communication settings.