Zero Trust Architecture in Modern Cybersecurity: Effectiveness, Limitations, and Adoption Barriers

The increasing complexity of digital infrastructures has exposed the limitations of traditional perimeter-based cybersecurity models. Zero Trust Architecture (ZTA) has emerged as a security paradigm that removes implicit trust and enforces continuous verification of users and devices. This paper reviews existing academic and institutional literature on ZTA, focusing on its effectiveness in mitigating cyber threats and the challenges associated with its adoption. Evidence from standards bodies and empirical studies indicates that ZTA reduces lateral movement and improves visibility across distributed systems. However, implementation complexity, cost, and integration with legacy systems remain significant barriers. The paper highlights the need for phased adoption strategies and improved policy frameworks to support effective deployment.