Microsegmentation is a vital security strategy that enhances protection by dividing networks into smaller, isolated segments, thereby limiting lateral movement by attackers and safeguarding critical assets.

As Operational Technology (OT) devices, which control physical processes like power grids and pipelines, become increasingly interconnected due to IoT and Industry 4.0, the associated security risks are also rising.

The vulnerabilities exposed during the American Water incident highlight the urgent need for Zero Trust Network Access (ZTNA) and effective network segmentation to protect OT systems.

Ransomware attacks are increasingly targeting critical infrastructure sectors such as energy, water, transportation, and finance, with over 40% of attacks in 2023 affecting these areas, according to the FBI.

Agencies like CISA and the UK's NCSC are alerting infrastructure companies about the escalating threats posed by state-sponsored adversaries and other malicious actors.

To enhance control and limit lateral movement of attackers, granular segmentation policies should be applied at the workload or application level.

Best practices for securing both IT and OT systems should be guided by zero-trust principles, starting with the assumption that a breach has occurred and focusing on minimizing its impact.

Companies should map their networks to identify critical assets and data flows, which aids in prioritizing protection efforts.

Implementing a secure backup solution for OT systems is essential to mitigate the impact of ransomware attacks, facilitating data restoration and minimizing downtime.

Regular monitoring and updates of segmentation policies are crucial to adapt to evolving infrastructure and strengthen defenses against potential breaches.

Greater visibility into OT systems is necessary for effective security and incident response, although this is less frequently implemented compared to IT systems.

Conducting penetration testing is important to identify vulnerabilities in segmentation strategies and ensure the proper isolation of network segments.