In smart home environments, Harvest Now and Decrypt Later (HNDL) attacks pose a significant threat to long-term privacy. Traditional elliptic curve cryptography (ECC)-based authentication systems can be neutralized using the Shor algorithm on quantum computers, making it difficult to mitigate these threats. In this study, we propose a hybrid authentication and key exchange protocol designed to address the resource constraints of smart home systems, while introducing the NIST standard post quantum cryptography (PQC) to defend against HNDL attacks. The proposed protocol operates through four concise steps: (1) Setup and Registration for identities and pre-shared keys (PSK); (2) Key Agreement between the user and gateway using ML-KEM; (3) Session Key Distribution from the gateway to the smart device (SD) using the PSK; and (4) Mutual Authentication to verify the established key across all nodes. Formal verification using ProVerif and Scyther confirms the security of the proposed protocol, which achieved a communication cost of 7424 bits, representing a 44–82% reduction compared to existing PQC protocols. Furthermore, the proposed protocol demonstrated an execution time of 0.3205 ms, achieving a 74–90% and 60–74% improvement over existing ECC-based and PQC-based methods, respectively. Consequently, this study presents a quantum-resistant authentication protocol for smart-home environments that achieves a practical balance between security and efficiency.
In smart home environments, Harvest Now and Decrypt Later (HNDL) attacks pose a significant threat to long-term privacy. Traditional elliptic curve cryptography (ECC)-based authentication systems can be neutralized using the Shor algorithm on quantum computers, making it difficult to mitigate these threats. In this study, we propose a hybrid authentication and key exchange protocol designed to address the resource constraints of smart home systems, while introducing the NIST standard post quantum cryptography (PQC) to defend against HNDL attacks. The proposed protocol operates through four concise steps: (1) Setup and Registration for identities and pre-shared keys (PSK); (2) Key Agreement between the user and gateway using ML-KEM; (3) Session Key Distribution from the gateway to the smart device (SD) using the PSK; and (4) Mutual Authentication to verify the established key across all nodes. Formal verification using ProVerif and Scyther confirms the security of the proposed protocol, which achieved a communication cost of 7424 bits, representing a 44–82% reduction compared to existing PQC protocols. Furthermore, the proposed protocol demonstrated an execution time of 0.3205 ms, achieving a 74–90% and 60–74% improvement over existing ECC-based and PQC-based methods, respectively. Consequently, this study presents a quantum-resistant authentication protocol for smart-home environments that achieves a practical balance between security and efficiency.
As smart home devices become more widely available, their limited resources and potential exposure to various types of cyber-attacks make it difficult for the traditional security protocols to remain effective. Cloud-enabled smart home IoT platforms have helped to improve device intelligence and overall efficiency when controlling them, but the additional use of cloud computing has also created additional complexity in controlling these devices through user-defined automated rules and remote access via vendor apps. Conventional security schemes do not consider these types of control models, nor do they provide a reasonable balance of the additional computational overhead introduced, the efficiency of communications, and the level of security provided. Additionally, with the introduction of quantum computing, current public key cryptography primitives will become obsolete, necessitating the requirement for an adoption of post-quantum security measures. To overcome these issues, this paper presents a proposal for a lightweight mutual authentication and key agreement scheme that employs post-quantum cryptography primitives to facilitate a secure interaction between the user’s cloud platforms, smart home devices, and the user. The protocol also supports remote secure control, while providing the resistance to both classical and quantum attacks. The proposed protocol has been thoroughly evaluated through formal verification using the ProVerif tool and multiple heuristic evaluation techniques. Additionally, the security features of the proposed protocol have been compared to those of several existing methods, providing evidence that it offers improved security features, forward secrecy, and quantum resistance while maintaining a lightweight profile compatible with the limitations of modern smart homes.
The imminent advent of quantum computing threatens the long-term security of classical public-key cryptography, creating critical challenges for resource-constrained internet of things (IoT) environments.Hybrid cryptographic frameworks combining elliptic curve cryptography (ECC) with post-quantum cryptography (PQC) primitives have emerged as a transitional solution; however, their security properties remain insufficiently validated under semi-trusted infrastructure assumptions.This paper presents a comprehensive security evaluation of a hybrid ECC-KEM authentication and key agreement framework targeting IoT deployments.Using a dual-verification methodology that integrates formal symbolic analysis with the Tamarin-Prover and practical AI-assisted testing via the APSVer tool, we identify a critical impersonation vulnerability that enables a semi-trusted third party (TTP) to reconstruct PUF-based authentication material.To mitigate this flaw, we introduce a protocol enhancement incorporating ML-DSA post-quantum digital signatures and device-isolated key derivation.Formal verification confirms that the enhanced protocol achieves mutual authentication, session key secrecy, replay resistance, and effective isolation of the TTP.Experimental performance analysis demonstrates that the proposed security improvements introduce only a 12%-15% computational overhead, preserving feasibility for constrained IoT devices.The proposed framework provides a practical, quantum-resilient authentication architecture suitable for next-generation secure IoT deployments.
Quantum cryptography represents a revolutionary paradigm shift in The rapid proliferation of smart home devices introduces significant security challenges, primarily due to their resource constraints and heterogeneous communication protocols. Cryptographic key exchange protocols play a pivotal role in establishing secure communication channels within smart home ecosystems. This article examines prominent key exchange mechanisms, evaluates their suitability for smart home environments, and proposes enhancements tailored to address the unique security threats faced by these systems. Through comparative analysis and graphical evaluation, this study provides insights into optimizing the balance between security, computational overhead, and energy efficiency. The results highlight that lightweight protocols such as Elliptic Curve Diffie-Hellman (ECDH) offer robust security with feasible performance for smart home deployments.
The emergence of fault-tolerant quantum computing poses an existential threat to classical public-key cryptographic systems, including RSA and Elliptic Curve Cryptography (ECC), through Shor's polynomial-time factorization algorithm. The Harvest Now, Decrypt Later (HNDL) attack paradigm further amplifies this threat by enabling adversaries to archive ciphertext today for future quantum-enabled decryption, rendering long-term data confidentiality immediately at risk. While the National Institute of Standards and Technology (NIST) finalized post-quantum cryptographic standards ML-KEM (FIPS 203) and ML-DSA (FIPS 204) in August 2024, their practical integration into complete application-level communication systems remains a largely unaddressed research gap. This paper presents QuantumShield, a hybrid post-quantum secure peer-to-peer communication platform that integrates ML-KEM-768 for quantum-safe key encapsulation, ML-DSA-65 for authenticated digital signatures, and AES-256-GCM for high-throughput symmetric encryption. Our primary research contribution is a rigorous empirical analysis of PQC integration overhead in a real-world communication pipeline, quantifying latency, key size, and security trade-offs against classical RSA-2048 and ECC-256 baselines under controlled experimental conditions. Experimental evaluation across 1,000 iterations demonstrates that ML-KEM-768 encapsulation completes in 2.8 ± 0.2 ms compared to 4.1 ± 0.3 ms for ECDH key agreement — a 32% latency reduction while providing NIST Level 3 post-quantum security. The complete secure transfer pipeline processes 1 MB files in under 22 ms on commodity hardware. The system further provides interactive cryptographic visualization, adversary threat modeling, tamper detection simulation, and a hybrid migration framework demonstrating practical transition from classical to post-quantum infrastructure. QuantumShield establishes that quantum-safe communication is not merely theoretical but deployable today with negligible performance compromise.
Device-to-device (D2D) communication is expected to become a key component of 6G and IoT systems, enabling low-latency and infrastructure-independent connectivity. A major challenge is to establish secure session keys between previously unknown devices without relying on an online trusted third party, while also ensuring resilience against future quantum adversaries. This paper proposes a lightweight hybrid authentication and key agreement protocol for decentralized D2D communication. The approach combines IPFS-assisted distributed key discovery with a two-message protocol that uses post-quantum key encapsulation for long-term confidentiality, while retaining elliptic curve cryptography (ECC) for efficient real-time authentication under classical security assumptions.This design reflects the different temporal security requirements of confidentiality and authentication and provides a practical trade-off between quantum resilience and computational efficiency. The proposed scheme achieves mutual authentication under classical ECC assumptions, secure session key establishment, and resistance against common attacks, while providing post-quantum confidentiality protection against future quantum adversaries and removing the need for an online trusted third party (TTP) during protocol execution. The results demonstrate that the protocol offers a competitive and practical solution for secure decentralized D2D communication in IoT and future 6G environments.
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.