ENHANCING CYBERSECURITY IN CLOUD COMPUTING USING ZERO TRUST ARCHITECTURE WITH ADAPTIVE RISK-BASED AUTHENTICATION

Abstract

Cloud computing has become a cornerstone of modern digital infrastructure, offering scalability, flexibility, and cost efficiency for organizations across various domains. However, its inherently distributed and multi-tenant nature introduces significant cybersecurity challenges, including unauthorized access, insider threats, account hijacking, and advanced persistent attacks. Traditional perimeter-based security models, which rely on the assumption of a trusted internal network, are no longer effective in mitigating these evolving threats in dynamic cloud environments. To address these limitations, this paper proposes a comprehensive and intelligent security framework that integrates Zero Trust Architecture (ZTA) with Adaptive Risk-Based Authentication (ARBA). The proposed framework operates on the principle of continuous verification, where every access request is evaluated in real time without assuming implicit trust. It incorporates a dynamic risk assessment engine that analyzes multiple contextual and behavioral factors, including user location, device characteristics, login history, and access patterns, to compute a risk score for each request. Based on the calculated risk level, the system dynamically enforces appropriate authentication mechanisms, ranging from single-factor authentication to multi-factor authentication or access denial. A mathematical risk model is formulated to quantify the influence of different risk parameters, enabling precise and adaptive decision-making. The framework is implemented and evaluated using a simulated cloud environment dataset consisting of diverse user behavior patterns over a defined time period. Experimental results demonstrate that the proposed model achieves a high accuracy of 95%, significantly reduces the false positive rate to 6%, and improves overall threat detection efficiency compared to traditional security approaches. Additionally, the adaptive nature of the system minimizes unnecessary authentication overhead, thereby maintaining a balance between security and user experience. The findings of this study highlight that the integration of Zero Trust principles with adaptive authentication mechanisms provides a scalable, efficient, and robust solution for securing modern cloud computing environments against increasingly sophisticated cyber threats.