Cybersecurity Challenges and Defense Mechanisms in IoT: A Comprehensive Analysis of Emerging Threats and Intelligent Solutions

Abstract

In the modern world, connected devices have revolutionized almost every aspect of life, from hospitals and factories to homes and city infrastructure. Today's large-scale IoT deployments have significantly expanded the attack surface, making it increasingly difficult for organizations to manage emerging cybersecurity risks. Legacy communication protocols, resource-constrained devices, and inadequate authentication mechanisms are frequently exploited for botnet recruitment, data theft, and service disruption. This paper provides a comprehensive overview of the IoT threat landscape and reviews defense mechanisms proposed to address these security challenges. It also examines the application of artificial intelligence (AI) and blockchain technologies in IoT security architectures while discussing emerging research directions, including federated learning, explainable AI, edge-native security, and post-quantum cryptography. The review concludes that no single security mechanism is sufficient to protect modern IoT ecosystems. Instead, a multilayered security strategy that integrates conventional security mechanisms with intelligent, adaptive technologies provides a more effective defense against evolving cyber threats.