Cybersecurity in IoT Ecosystems: Risks, Protocols, and Protection Mechanisms

<p dir="ltr">The fast development of Internet of Things (IoT) systems has brought about new challenges to the cybersecurity problem that require effective and dynamic protection measures. This is a systematic literature review that explores the risks, protocols, and protection mechanisms implemented in the IoT contexts and summarizes the results gathered in 75 scholarly publications published between 2015 and 2025. According to the review, the IoT security environment is set to evolve, with such protocols as MQTT, CoAP, Zigbee, LoRaWAN, and 6LoWPAN being actively researched in terms of their vulnerabilities and robustness. Distributed denial-of-service (DDoS), spoofing, firmware tampering, and the unauthorized access are commonly recognized threats, as such a level of risk demands the thorough risk mitigation methodology. The mechanisms of protection are varied, and the majority are device authentication (42.67%), intrusion detection systems (34.67%), and blockchain-based solutions (22.67%), which are the most central in the prevailing IoT security architectures. The majority of studies (61.33) did not have clear evaluation criteria, including latency, energy usage, or security ratings, curtailed cross-comparisons, and methodological clarity. The specific applications of the industry show strong emphasis on industrial internet of things (32.00%), smart homes (21.33%), and healthcare internet of things (17.33%), which indicates the domain sensitivity of cybersecurity policies. In spite of this improvement, the IoT ecosystems still have to deal with the heterogeneity of devices, limited resources, and partial standardization that prevent the implementation of the large-scale secure deployment. This review promotes standardized structures, slim cryptographic schemes, and experimental underpinning of suggested tools to enhance the resilience of the IoT. The next generation of research ought to focus on cross-layer security solutions, industry-specific authentication and assimilation of new technology including artificial intelligence that will be proactive in dealing with any new forms of cyber threats.</p>