Lightweight cryptography for IoT: A comprehensive survey of algorithms, implementations, and standardization

The Internet of Things (IoT) paradigm has enabled seamless connectivity among billions of constrained devices—sensors, actuators, and smart appliances—yet securing these networks remains a critical challenge. Traditional cryptographic primitives often exceed typical IoT endpoints' power, memory, and latency budgets. This paper thoroughly surveys lightweight cryptography specifically designed for Internet of Things (IoT) environments. We first introduce a taxonomy of algorithmic families—including block and stream ciphers, public-key schemes, and hash functions—and review recent proposals that achieve high-security margins with minimal resource footprints. Next, we analyze efficiency optimizations at both the algorithmic and architectural levels, covering hardware accelerators, side-channel countermeasures, and software-only implementations. We then examine ongoing efforts toward standardization and interoperability, focusing on emerging post-quantum candidates suitable for constrained platforms. We illustrate practical deployment trade-offs in throughput, energy consumption, and resilience under realistic attack models through detailed case studies- spanning smart metering, industrial control, and wearable devices. Finally, we identify open challenges and research directions, including further reductions in computational overhead, integration of quantum-resistant primitives, and the development of unified frameworks for large-scale, energy-efficient key management. Our survey highlights the pressing need for quantum-aware, scalable, and lightweight cryptographic solutions to safeguard the next generation of IoT applications.