The approval of NERC CIP-015-1 marks a major shift in how critical infrastructure operators must defend their environments. For years, compliance efforts focused on keeping attackers out, but CIP-015-1 recognizes that perimeter defenses alone are not enough.
Now, asset owners are required to monitor internal network activity to detect and respond to threats moving laterally within trusted networks. This new standard isn’t just a regulatory hurdle; it’s an opportunity to align compliance with meaningful security improvements that strengthen your operations against modern threats.
1. Introduction
FERC’s approval of NERC CIP-015-1 marks a pivotal shift in how critical infrastructure operators must secure their environments. This new standard moves beyond perimeter-focused security to require continuous internal network monitoring to detect lateral movement within trusted zones. At Critical Path Security, we see this as an opportunity for asset owners to align compliance with stronger defense against advanced threats.
2. What Is CIP-015-1 and Why It Matters
CIP-015-1 applies to all High-Impact Bulk Electric System (BES) Cyber Systems, regardless of whether they have external routable connectivity, and to Medium-Impact systems that do have external routable connectivity. The focus is on expanding visibility within electronic security perimeters to detect threats moving laterally, reducing the window of undetected attacker activity within operational environments.
3. Core Requirements (R1 to R3)
Requirement 1 involves collecting, detecting, and analyzing network activity. This includes risk-based selection of data feeds, behavior-based detection of anomalies, and timely evaluation of flagged activity.
Requirement 2 requires retaining INSM data relevant to identified anomalies for at least three years to support investigation and response efforts.
Requirement 3 mandates the protection of collected INSM data to prevent tampering or unauthorized deletion, ensuring the integrity of security evidence.
4. Timeline and Compliance Deadlines
The final rule was published in late June and early July 2025, with an effective date of September 2, 2025. Compliance will begin with control centers and backup control centers first, with Medium-Impact systems with external routable connectivity following by September 2027. High-Impact systems will follow by September 2028, aligning with the 36-month phased implementation timelines.
5. Future Scope Including EACMS and PACS
FERC has directed NERC to expand CIP-015 to include monitoring Electronic Access Control and Monitoring Systems and Physical Access Control Systems outside of electronic security perimeters. This anticipated expansion under CIP-015-2 will require organizations to monitor lateral traffic across badge systems, VPN services, and identity systems, extending the reach of visibility efforts beyond traditional boundaries.
6. Practitioner Guidance and Action Steps
Assess and plan by mapping High-Impact and Medium-Impact BES assets, cataloging current network visibility tools inside ESP zones, and defining baseline traffic profiles across substation and control environments.
Pilot and scale your approach by starting with a control center or critical ESP zone, deploying lightweight sensors, configuring behavioral detection, and gradually expanding to include Electronic Access Control and Monitoring Systems and Physical Access Control Systems in your second phase of implementation.
7. How Critical Path Security Helps
We provide passive OT visibility sensors specifically tuned for substation and ICS environments, enabling collection of east-west traffic data without impacting operations. Our behavioral analytics engine identifies deviations from baseline traffic patterns to detect suspicious lateral movement. We offer secure log management to retain and protect INSM data for compliance and investigations while ensuring scalability to include Electronic Access Control and Monitoring Systems and Physical Access Control Systems as the regulations expand. Our managed readiness services help with pilot deployments, tuning, documentation, and preparation for audits.
8. Checklist for Asset Owners
Inventory High-Impact and Medium-Impact BES assets and their electronic security perimeter memberships
Map network segments for initial monitoring
Establish baseline traffic profiles
Deploy sensors and configure anomaly detection processes
Implement retention and integrity protections for INSM data
Pilot Electronic Access Control and Monitoring Systems and Physical Access Control Systems monitoring
Develop incident evaluation workflows and playbooks
Prepare compliance evidence for upcoming audits
9. Conclusion and Call to Action
CIP-015-1 transforms compliance into proactive defense by making internal network monitoring a security standard for critical infrastructure operators. Critical Path Security offers proven OT expertise and operational monitoring solutions to help you meet CIP-015-1 requirements while strengthening your overall security posture.
If you are ready to prepare your environment for CIP-015-1 compliance while improving your visibility and detection capabilities, contact Critical Path Security today to discuss pilot programs and readiness assessments tailored to your operational environment.