Advances in Security Maturity and Architecture Design in Critical Infrastructures

Critical infrastructures such as power grids, water treatment facilities, and gas production plants are increasingly reliant on Industrial Control Systems (ICS). However, these systems are subject to a growing array of sophisticated cyber threats. This paper presents a state-of-the-art review of security maturity frameworks and secure architecture designs tailored for IT/OT environments in critical infrastructure settings. The PRISMA methodology was employed to guide the selection of articles, and the AI-enhanced platform Elicit for peer-reviewed publications in the last 5 years. This yielded 60 pertinent studies. Our analysis identifies a clear preference for modular maturity models, such as the NIST Cybersecurity Framework and DOE's C2M2, to benchmark and advance security posture. At the architectural level, we emphasize fundamental controls, including network segmentation, access proxies, next-generation firewalls, and Zero Trust implemented via SDN. These are integrated with hierarchical layering and active-deception honeypots. We conclude by recommending continuous, context-aware, multidomain risk management schemes to enhance the resilience and reliability of critical infrastructure operations.