/S01 · FocusStack

OT Security

When downtime is not an option

Production facilities, energy supply, water treatment, building automation — Operational Technology controls the physical processes on which the economy and society depend. However, the convergence of IT and OT creates vulnerabilities that cannot be managed with traditional IT security concepts.

ISD FENIQS secures your OT environments—with passive monitoring, systematic vulnerability management, and managed services that balance availability and security.

/S02 · Context

The End of Isolation

For decades, OT environments were considered secure because they were separated from the corporate network. That era is over. The digitalization of industrial processes has blurred the line between IT and OT. This includes predictive maintenance, cloud-based analytics, and remote access for machine manufacturers. Systems that were never designed for network connectivity are now exposed.

At the same time, the regulatory framework is significantly increasing the pressure to act. The NIS2 Implementation Act has been in force in Germany since December 2025. Under this law, KRITIS operators are automatically classified as particularly important facilities. In the event of security incidents, the reporting obligation is 24 hours, and the BSI can initiate proactive supervisory measures at any time.

This has significant consequences for manufacturing companies in the NIS2 sectors. These sectors include energy, water, chemicals, food, and manufacturing. OT security is no longer an optional measure but a compliance requirement with personal liability for managing directors.

The threat landscape underscores this urgency. Ransomware attacks on industrial control systems have multiplied in recent years. Attackers know that a production shutdown causes immediate economic damage and thus increases the willingness to pay.

Where IT security traditionally prioritizes confidentiality, OT security must protect availability. This difference in priority requires specialized approaches.

NIS2KRITISBSI-GesetzIEC 62443IT/OT-KonvergenzKRITIS-DachG

/S03 · Our Position

Security that doesn’t jeopardize operations

At ISD FENIQS, we are convinced that OT security must operate by its own rules. Traditional IT security methods can have catastrophic consequences in a production environment. These include aggressive scans, forced patches, and reboot cycles. An unplanned reboot of a control system is not an IT ticket, but a production outage.

That is why we take an approach that prioritizes visibility. Before we protect, we first understand your OT environment: What assets exist there? How do they communicate with each other? Which vulnerabilities are known, and which are actually relevant in the operational context?

Passive network monitoring, agentless asset discovery, and an assessment that takes the operational context into account form the foundation of every security measure.

At the same time, we understand that OT security cannot be viewed in isolation. The convergence of IT and OT is a reality and will continue to be necessary. Data-driven manufacturing, remote maintenance, and cloud connectivity create real business value. The task is not to prevent this convergence, but to make it secure.

This requires several measures: network segmentation that actually works, controlled transitions between IT and OT zones, and monitoring that covers both worlds.

OT security does not begin with control, but with visibility. You cannot protect what you do not know.
— Rastislav Novobilsky · Head of Cybersecurity & Cloud Services

/S04 · Expertise

How we operationalize OT security

Our OT security services follow the principle of “visibility before protection before response.” Each component can be used individually. However, the full impact is realized when they work together as a managed service with predictable costs and without burdening your internal teams.

Managed Services & Solutions

OT Asset Discovery

Passive, agentless discovery of all OT assets: PLCs, SCADA systems, network components, and IoT devices. Without any operational downtime, you receive a complete inventory of your industrial infrastructure as a foundation for further security measures.

OT vulnerability scanning

Systematic vulnerability identification in OT network segments using passive methods without operational disruption. Prioritization based on operational risk: not just CVSS scores, but also actual accessibility and criticality in a production context.

Netzwork Segmentation

Architectural consulting and implementation of zone and conduit models according to IEC 62443. Controlled transitions between IT and OT networks, industrial firewalls, and DMZ architectures that enable data flow while disrupting attack paths.

OT Security Monitoring

Continuous monitoring of OT network traffic for anomalies, unauthorized communication, and behavioral changes. Integration into our Security Operations for correlated threat detection across IT and OT environments.

Compliance & Advisory

NIS2-compliant documentation, risk assessment, and audit preparation for OT environments. Support with BSI registration, security incident reporting processes, and OT security policies in accordance with IEC 62443 and BSI Basic Protection.

IT/OT Convergence Architecture

Strategic consulting for the secure convergence of IT and OT infrastructures. Architecture design for data-driven manufacturing, predictive maintenance, and remote access without compromising OT integrity.