Zero Trust Architecture for Substations – Solutions and Leading Firms like Claroty

As utility companies embrace digital transformation and Industry 4.0, Zero Trust Architecture (ZTA) in substations is rapidly evolving from a theoretical framework to a practical cybersecurity strategy. This follow-up explores how electric utilities and critical infrastructure providers can turn ZTA principles into action using robust Operational Technology (OT) security solutions, focusing on top cybersecurity vendors like Claroty, Fortinet, Palo Alto Networks, Nozomi Networks, and others.

Practical Zero Trust Cybersecurity Solutions for Power Substations

1. Asset Discovery & OT Network Visibility

Objective: Know what’s in your OT network before protecting it.

Leading OT cybersecurity tools:

• Claroty Continuous Threat Detection (CTD) – Performs passive deep-packet inspection to auto-identify assets like IEDs, RTUs, PLCs, HMIs.

• Nozomi Guardian – Offers protocol-aware ICS asset discovery and threat detection.

• Cisco Cyber Vision – Integrates with industrial switches to enhance network visibility.

2. OT Network Segmentation and Zoning

Objective: Prevent lateral movement across different zones in substations (Bay, Control, Engineering, SCADA).

Solutions:

• Fortinet FortiGate firewalls with OT policies for east-west segmentation.

• Palo Alto NGFW using App-ID for protocols like IEC 61850 and DNP3.

• Claroty Secure Remote Access (SRA) for policy-driven zone separation.

3. Identity & Access Management (IAM) for OT Environments

Objective: Grant access to the right person, system, and time, minimizing insider threats.

Solutions:

• Claroty SRA – Secure remote access with session recording.

• CyberArk – Privileged access management for critical OT systems.

• Microsoft Active Directory with MFA – For RBAC-based access governance.

4. Encrypted & Authenticated Communications in OT Networks

Objective: Protect data confidentiality and integrity.

Solutions:

• DNP3-SA, IEC 62351 – SCADA protocol encryption standards.

• TLS/IPSec VPNs – For secure remote channel setup.

• Vendor firmware signing tools – Ensuring update authenticity.

5. Monitoring, Threat Detection & OT Incident Response

Objective: Detect and respond to cyber threats in real-time within substations.

Solutions:

• Claroty CTD – Uses machine learning to detect anomalies in ICS traffic.

• SIEM platforms like Splunk, IBM QRadar – For log analysis and event correlation.

• SOAR tools – For automated incident response workflows.

Detection examples:

• Unauthorized firmware changes

• Abnormal GOOSE messaging

6. Secure Remote Access for OT Systems (SDP vs VPN)

Objective: Replace legacy VPNs with scalable, zero-trust remote access.

Solutions:

• Claroty SRA – Replaces VPN, logs access sessions, enforces least privilege.

• ZScaler Private Access (ZPA) – SDP-based secure cloud access.

• BeyondTrust/Duo – Additional access control layers for OT environments.

Top Cybersecurity Vendors Leading Zero Trust in OT Substations

Zero Trust Toolkit for Utility OT Security Teams

Business Benefits of Zero Trust for Substations

• Cybersecurity Hardening: Prevents breach propagation in substations.

• Regulatory Compliance: Aligns with NERC-CIP, IEC 62443, CERT-In guidelines.

• Faster OT Incident Response: Thanks to real-time visibility and analytics.

• Scalable Architecture: Start with one substation and scale OT security fleet-wide.

Next Steps for Utilities, EPCs & Power Sector Leaders

1. Collaborate with leading OT cybersecurity firms like Claroty and Nozomi for ZTA deployment.

2. Conduct an OT risk assessment to identify vulnerable points in your substation.

3. Implement a ZTA pilot in a digital substation.

4. Scale gradually using a risk-based approach across multiple substations.

Conclusion

Zero Trust Architecture is not just a future aspiration—it is now a critical necessity for substation cybersecurity. With advanced solutions from companies like Claroty, Fortinet, and Nozomi Networks, utility companies can transition their vulnerable OT systems into secure, resilient, and compliant digital infrastructure.