Resource-constrained devices such as wireless sensors and Internet of Things (IoT) devices have become ubiquitous in our digital ecosystem. These devices generate and handle a major part of our digital data. However, due to the impending threat of quantum computers on our existing public-key cryptographic schemes and the limited resources available on IoT devices, it is important to design lightweight post-quantum cryptographic (PQC) schemes suitable for these devices.In this work, we explored the design space of learning with error-based PQC schemes to design a lightweight key-encapsulation mechanism (KEM) suitable for resourceconstrained devices. We have done a scrupulous and extensive analysis and evaluation of different design elements, such as polynomial size, field modulus structure, reduction algorithm, and secret and error distribution of an LWE-based KEM. Our explorations led to the proposal of a lightweight PQC-KEM, Rudraksh, without compromising security. Our scheme provides security against chosen ciphertext attacks (CCA) with more than 100 bits of Core-SVP post-quantum security and belongs to the NIST-level-I security category (provide security at least as much as AES-128). We have also shown how ASCON can be used for lightweight pseudo-random number generation and hash function in the lattice-based KEMs instead of the widely used Keccak for lightweight design. Our FPGA results show that Rudraksh currently requires the least area among the PQC KEMs of similar security. Our implementation of Rudraksh provides a ~3x improvement in terms of the area requirement compared to the state-of-the-art areaoptimized implementation of Kyber, can operate at 63%-76% higher frequency with respect to high-throughput Kyber, and improves time-area-product ~2x compared to the state-of-the-art compact implementation of Kyber published in HPEC 2022.
Resource-constrained devices such as wireless sensors and Internet of Things (IoT) devices have become ubiquitous in our digital ecosystem. These devices generate and handle a major part of our digital data. However, due to the impending threat of quantum computers on our existing public-key cryptographic schemes and the limited resources available on IoT devices, it is important to design lightweight post-quantum cryptographic (PQC) schemes suitable for these devices.In this work, we explored the design space of learning with error-based PQC schemes to design a lightweight key-encapsulation mechanism (KEM) suitable for resourceconstrained devices. We have done a scrupulous and extensive analysis and evaluation of different design elements, such as polynomial size, field modulus structure, reduction algorithm, and secret and error distribution of an LWE-based KEM. Our explorations led to the proposal of a lightweight PQC-KEM, Rudraksh, without compromising security. Our scheme provides security against chosen ciphertext attacks (CCA) with more than 100 bits of Core-SVP post-quantum security and belongs to the NIST-level-I security category (provide security at least as much as AES-128). We have also shown how ASCON can be used for lightweight pseudo-random number generation and hash function in the lattice-based KEMs instead of the widely used Keccak for lightweight design. Our FPGA results show that Rudraksh currently requires the least area among the PQC KEMs of similar security. Our implementation of Rudraksh provides a ~3x improvement in terms of the area requirement compared to the state-of-the-art areaoptimized implementation of Kyber, can operate at 63%-76% higher frequency with respect to high-throughput Kyber, and improves time-area-product ~2x compared to the state-of-the-art compact implementation of Kyber published in HPEC 2022.
Current improvements in quantum computing present a substantial challenge to classical cryptographic systems, which typically rely on problems that can be solved in polynomial time using quantum algorithms. Consequently, post-quantum cryptography (PQC) has emerged as a promising solution to emerging quantum-based cryptographic challenges. The greatest threat is public-key cryptosystems, which are primarily responsible for key exchanges. In PQC, key encapsulation mechanisms (KEMs) are crucial for securing key exchange protocols, particularly in Internet communication, virtual private networks (VPNs), and secure messaging applications. CRYSTALS-Kyber and NTRU are two well-known PQC KEMs offering robust security in the quantum world. However, even when quantum computers are functional, they are not easily accessible. IoT devices will not be able to utilize them directly, so there will still be a requirement to protect IoT devices from quantum attacks. Concerns such as limited computational power, energy efficiency, and memory constraints in devices such as those used in IoTs, embedded systems, and smart cards limit the use of these techniques in constrained environments. These concerns always arise there. To address this issue, this study conducts a broad comparative analysis of Kyber and NTRU, with special focus on their security, performance, and implementation efficiency in such environments (IOT/constrained environments). In addition, a case study was conducted by applying KEMs to a low-power embedded device to analyze their performance in real-world scenarios. These results offer an important comparison for cyber security engineers and cryptographers who are involved in integrating post-quantum cryptography into resource-constrained devices.
The emergence of quantum computing threatens classical cryptographic systems, including RSA and ECC, potentially compromising the security of pervasive Internet of Things (IoT) deployments. Resourceconstrained IoT devices—such as sensors, embedded controllers, and microcontrollers—face significant challenges in adopting post-quantum cryptographic (PQC) protocols due to computational, memory, and energy limitations. This paper proposes AQ-PQC, an adaptive lightweight hybrid key exchange protocol combining Kyber lattice-based KEM and lightweight elliptic curve cryptography (ECC), specifically designed for constrained devices. AQ-PQC introduces a dynamic parameter tuning algorithm that adjusts key sizes, handshake rounds, and compression ratios based on real-time device state and network conditions. Formal security analysis under the IND-CCA model demonstrates quantum-resistance and forward secrecy. Extensive hardware implementation on Raspberry Pi 4 and ESP32 devices reveals a significant reduction in handshake latency, energy consumption, and memory footprint compared to conventional PQC protocols. The proposed framework provides a practical, reproducible, and secure methodology for post-quantum IoT communications, supporting heterogeneous and resource-limited networks.
Following the completion of the NIST post-quantum cryptography standardization, Kyber has been adopted as a key encapsulation mechanism (KEM) for quantum-resistant communication. Although lattice-based KEMs provide strong security and efficiency, most existing designs restrict the cyclotomic ring dimension to powers of two, which limits parameter flexibility for heterogeneous and resource-constrained Internet of Things (IoT) devices. In this paper, we propose Fyber, a post-quantum KEM based on the Module Learning With Errors (M-LWE) problem over a module ring defined by the cyclotomic polynomial f(x)=xn−xn/2+1, where n is a product of powers of 2 and 3. This construction enables mixed-radix parameter selection and allows finer-grained trade-offs between security and efficiency. To further improve performance on constrained platforms, we introduce an efficient non-Gaussian sampling method. The proposed KEM supports flexible security-level stratification for IoT applications, achieving reduced public key and ciphertext sizes for selected parameter sets at the cost of moderately increased computational overhead compared to Kyber, and fills intermediate security gaps between existing standardized parameter sets.
Quantum computing is also posing a serious challenge to the classical cryptographic algorithms like RSA and ECC as they have vulnerability to quantum algorithms such as Shor and Grover. This is a serious problem to Internet of Things (IoT) and edge computing systems, where billions of devices work with strict resource constraints in processing power, memory and energy. To resolve this, we are introducing a minimal postquantum cryptography model to be used in edge platforms with constraints on their resources. This framework combines fierce encapsulation of key (Kyber512) on a lattice with traditional ECDH in a hybrid system of key establishment, along with the Ascon AEAD encryption algorithm to provide effective data hiding and integrity provision. Furthermore, rekeying and forward secrecy on a lightweight basis is possible to reconfigure a layer with negligible overhead on a secure transmission with forward secrecy. The experimental data with ARM Cortex-M and RISC-V architectures and 128-bit post-quantum security has shown that the proposed system can reduce the latency by up to 30 percent and the energy usage by up to 35 percent and considerably better throughput than PQC-only implementations. These findings validate the fact that hybrid PQC solutions have the potential to provide high-resistance quantum with minimal overhead and thus are best suited to IoT and edge applications. The paper offers a viable and extensible security design in conformance with the NIST PQC and IETF migration policies, which can support secure communication in the post-quantum era.
The rapid advancement of quantum computing poses a critical threat to classical cryptographic algorithms such as RSA and ECC, particularly in Internet of Things (IoT) devices, where secure communication is essential but often constrained by limited computational resources. This paper investigates the feasibility of deploying post-quantum cryptography (PQC) algorithms on resource-constrained devices. In particular, we implement three PQC algorithms - BIKE, CRYSTALS-Kyber, and HQC - on a lightweight IoT platform built with Raspberry Pi devices. Leveraging the Open Quantum Safe (liboqs) library in conjunction with mbedTLS, we develop quantumsecure key exchange protocols, and evaluate their performance in terms of computational overhead, memory usage, and energy consumption for quantum secure communication. Experimental results demonstrate that the integration of PQC algorithms on constrained hardware is practical, reinforcing the urgent need for quantum-resilient cryptographic frameworks in next-generation IoT devices. The implementation of this paper is available at https://iqsec-lab.github.io/PQC-IoT/.
The rapid advancement of quantum computing poses a critical threat to classical cryptographic algorithms such as RSA and ECC, particularly in Internet of Things (IoT) devices, where secure communication is essential but often constrained by limited computational resources. This paper investigates the feasibility of deploying post-quantum cryptography (PQC) algorithms on resource-constrained devices. In particular, we implement three PQC algorithms - BIKE, CRYSTALS-Kyber, and HQC - on a lightweight IoT platform built with Raspberry Pi devices. Leveraging the Open Quantum Safe (liboqs) library in conjunction with mbedTLS, we develop quantumsecure key exchange protocols, and evaluate their performance in terms of computational overhead, memory usage, and energy consumption for quantum secure communication. Experimental results demonstrate that the integration of PQC algorithms on constrained hardware is practical, reinforcing the urgent need for quantum-resilient cryptographic frameworks in next-generation IoT devices. The implementation of this paper is available at https://iqsec-lab.github.io/PQC-IoT/.