A Review on Internet of Things Security: Requirements, Challenges and Solutions

Background: Internet of Things (IoT) is one of the most promising technologies that aims to enhance humans’ quality of life (QoL). IoT plays a significant role in several fields such as healthcare, automotive industries, agriculture, education, and many cross-cutting business applications. Objectives: This paper explores the multifaceted security issues of IoT environments, highlighting current gaps and presenting modern technological solutions. This paper aims to systematically explore the diverse security challenges in IoT environments, critically assess current technological solutions, and identify unresolved issues along with potential directions for future research. Methods: A systematic literature review was conducted for the period 2020–2025, covering more than 50 studies from IEEE, ACM, Elsevier, and SpringerLink. Selected papers were evaluated based on relevance, peer-review status, and contribution to IoT security. Findings: IoT systems face unique challenges such as weak authentication, lightweight encryption requirements, and large-scale heterogeneity. This study synthesizes current solutions like multi-factor authentication, blockchain, and machine learning for intrusion detection. Novelty: Unlike traditional reviews, this paper evaluates technologies under real-world constraints and identifies specific research gaps such as scalable lightweight security frameworks and zero-trust model adoption in IoT. Significance: The paper provides the most extensive survey of security issues associated with the IoT. Based on an up-to-date analysis of different IoT security frameworks and standards proposed in the literature, the paper contributes to the field by pointing out the directions in which further research is needed. It’s one of the most cited survey papers in IoT security, meaning many other researchers trust and refer to it.