Message Queue Telemetry Transport (MQTT) is a common communication protocol used in the Internet of Things (IoT). MQTT is a simple, lightweight messaging protocol used to establish communication between multiple devices relying on the publish–subscribe model. However, the protocol does not provide authentication, and most proposals to incorporate it lose their lightweight feature and do not consider the future risk of quantum attacks. IoT devices are generally resource-constrained, and postquantum cryptography is often more computationally resource-intensive compared to current cryptographic standards, adding to the complexity of the transition. In this paper, we use the postquantum digital signature scheme CRYSTALS-Dilithium to provide authentication for MQTT and determine what the CPU, memory and disk usage are when doing so. We further investigate another possibility to provide authentication when using MQTT, namely a key encapsulation mechanism (KEM) trick proposed in 2020 for transport level security (TLS). Such a trick is claimed to save up to 90% in CPU cycles. We use the postquantum KEM scheme CRYSTALS-KYBER and compare the resulting CPU, memory and disk usages with traditional authentication. We found that the use of KEM for authentication resulted in a speed increase of 25 ms, a saving of 71%. There were some extra costs for memory but this is minimal enough to be acceptable for most IoT devices.
Message Queue Telemetry Transport (MQTT) is a common communication protocol used in the Internet of Things (IoT). MQTT is a simple, lightweight messaging protocol used to establish communication between multiple devices relying on the publish–subscribe model. However, the protocol does not provide authentication, and most proposals to incorporate it lose their lightweight feature and do not consider the future risk of quantum attacks. IoT devices are generally resource-constrained, and postquantum cryptography is often more computationally resource-intensive compared to current cryptographic standards, adding to the complexity of the transition. In this paper, we use the postquantum digital signature scheme CRYSTALS-Dilithium to provide authentication for MQTT and determine what the CPU, memory and disk usage are when doing so. We further investigate another possibility to provide authentication when using MQTT, namely a key encapsulation mechanism (KEM) trick proposed in 2020 for transport level security (TLS). Such a trick is claimed to save up to 90% in CPU cycles. We use the postquantum KEM scheme CRYSTALS-KYBER and compare the resulting CPU, memory and disk usages with traditional authentication. We found that the use of KEM for authentication resulted in a speed increase of 25 ms, a saving of 71%. There were some extra costs for memory but this is minimal enough to be acceptable for most IoT devices.
The proliferation of Internet of Things (IoT) devices that use the Message Queuing Telemetry Transport (MQTT) protocol poses significant security challenges in the emerging quantum computing era. Current Transport Layer Security (TLS) implementations rely on classical cryptographic algorithms vulnerable to Shor's algorithm. This paper proposes PQ-MQTT, a hybrid post-quantum secure communication protocol that integrates ML-KEM-768 with X25519 for key encapsulation and a lightweight session-key derivation mechanism optimized for resource-constrained IoT publishers. We present a formal security analysis under the Quantum Random Oracle Model (QROM), demonstrating resilience against store-now-decryptlater attacks. Experimental evaluation on the Raspberry Pi 4, ESP32, and Arduino Nano 33 platforms shows that PQ-MQTT achieves handshake latencies of127.3ms,412.7ms, and1,847.2ms, respectively, with 18.2 KB of additional memory overhead. A comparative analysis of pure post-quantum and classical TLS implementations shows energy reductions of23.5%−40.5%relative to pure PQC, achieved through our hybrid optimization approach, while maintaining 94.2 % throughput efficiency.
The rapid advancement of quantum computing poses significant threats to classical cryptographic methods, such as Rivest–Shamir–Adleman (RSA) and Elliptic Curve Cryptography (ECC), which currently secure Internet of Things (IoT) and cloud communications. Post-Quantum Cryptography (PQC), particularly lattice-based schemes, has emerged as a promising alternative. CRYSTALS-Kyber, standardized by the National Institute of Standards and Technology (NIST) as ML-KEM, has shown efficiency and practicality for constrained IoT devices. Most existing research has focused on PQC within the Transport Layer Security (TLS) protocol. Consequently, a critical gap exists in understanding PQC’s performance in lightweight IoT protocols. These are Message Queuing Telemetry Transport (MQTT) and Constrained Application Protocol (CoAP), particularly under adverse network conditions. To address this gap, this paper provides a systematic review of the literature on the network resilience and performance of CRYSTALS-Kyber when integrated into these protocols operating over lossy and high-latency networks. Additional challenges include non-standardized integration, resource limitations, and side-channel vulnerabilities. This review provides a structured synthesis of current knowledge, highlights unresolved trade-offs between security and efficiency, and outlines future research directions, including protocol-level optimization, lightweight signature schemes, and resilience testing of PQC-secured IoT protocols under realistic conditions.
Abstract The Post-Quantum Lightweight Key Sharing Protocol for Secure MQTT-Based IoT Networks (PQLKS-MQTT) addresses the critical need for quantum-resistant and resource-efficient security in IoT communications. As the proliferation of IoT devices continues, securing MQTT-based networks against evolving threats, including quantum attacks, becomes imperative. PQLKS-MQTT integrates the Kyber Key Encapsulation Mechanism for post-quantum key exchanges, along with BLAKE2s hashing and ChaCha20 encryption, to ensure robust security with minimal resource consumption. Implemented using the Cooja simulator with Contiki OS, Eclipse Mosquitto MQTT broker, and Open Quantum Safe (liboqs) library, the protocol demonstrates superior performance compared to state-of-the-art solutions. Experimental results show that PQLKS-MQTT achieves the lowest CPU energy consumption (0.0000021 mJ), fastest execution time (0.35 seconds), and minimal computational (260 CPU cycles) and communication overheads (55 bytes), with only a slight increase in average energy consumption (0.00145 mJ) due to post-quantum cryptographic operations. This balance between enhanced security and efficient resource utilization makes PQLKS-MQTT a suitable solution for resource-constrained IoT devices and large-scale deployments, offering a scalable, quantum-safe communication framework for future IoT ecosystems.
The rapid expansion of the Internet of Things (IoT) has introduced millions of resource-constrained devices into critical infrastructures, consumer environments, and industrial systems. These devices rely on lightweight communication protocols such as MQTT to support low-power, intermittent, and bandwidth-limited operation. However, common TLS algorithms used to secure MQTT communications are vulnerable to quantum attacks made feasible by Shor's algorithm. As a result, IoT infrastructures must evaluate and adopt post-quantum cryptographic (PQC) methods capable of providing long-term resilience. This report investigates the implementation of PQC algorithms within an MQTT-based IoT networks using three Raspberry Pis. Specifically, it integrates the FALCON digital signature scheme, one of NIST's selected post-quantum signature algorithms, to maintain message authenticity and integrity across resource-constrained MQTT clients and brokers. By measuring system performance, the research characterizes the practical trade-offs of deploying lattice-based PQC on lightweight hardware.
The integration of Internet of Things (IoT) technology into transportation systems to enable real-time data collection and analysis helps to achieve increased efficiency and enhanced user experience. However, the IoT network faces significant cybersecurity challenges, especially with the advent of quantum computing, which poses a serious threat to classical security schemes. This paper proposes an authentication protocol for IoT-based transportation systems using CRYSTALS-Kyber, a lattice-based Post-Quantum Key Encapsulation Mechanism (PQKEM), and Quantum Random Number Generators (QRNGs) together with lightweight cryptographic operations. In contrast to the existing literature, the proposed protocol is lightweight and provides protection against conventional and quantum attacks while adhering to standards and ensuring interoperability with future systems. We provide a formal security proof of the proposed protocol using the Real-Or-Random (RoR) model and analyze its security under the Canetti-Krawczyk (CK) adversary model. The performance analysis shows that the protocol offers strong security and scalability with minimal computational overhead compared to existing schemes. Additionally, we assess the performance of the proposed protocol through simulations conducted with the NS3 simulator.
The integration of Internet of Things (IoT) technology into transportation systems holds immense potential to transform the way we move people and goods, offering benefits such as increased efficiency, reduced emissions, improved safety, and enhanced user experience. With the ubiquitous and high-speed connectivity, sixth-generation (6G) technology is envisaged to make unprecedented revolutions in several fields and applications including IoT applications and transportation systems. The convergence of 6G networks with these applications will provide seamless connectivity and help to integrate functionalities such as sensing, communication, and computing, resulting in superior service quality. However, the IoT network is highly vulnerable to cyber-attacks. With the recent developments in quantum computers and quantum algorithms, it is important to make them secure from quantum attacks as well. In this paper, we propose a quantum-safe authentication protocol using a Post-Quantum Key Encapsulation Mechanism (PQKEM) for IoT applications in transportation systems. The protocol is built using CRYSTALS-Kyber, a lattice-based PQKEM, selected by the National Institute of Standards and Technology (NIST) in round 3 of the post-quantum standardization process. We provide a formal security proof of the proposed authentication protocol using the Real-Or-Random (RoR) model. We also present a performance analysis of the proposed authentication protocol.