01 / The guide
What's inside
- OT asset discovery and inventory
- Criticality and consequence assessment
- Zones, conduits, and IT/OT DMZ architecture
- Segmentation and controlled remote access
- OT monitoring, vulnerability, and incident management
- Backup, recovery, and resilience planning
02 / The context
Why this guide matters
OT environments have safety, availability, and operational constraints that make conventional IT security patterns insufficient on their own. This guide focuses on protecting processes, reducing attack paths, and improving recovery without introducing unsafe operational change.
03 / The practical view
Key insights
Account for performance, reliability, and safety requirements when selecting OT security controls.
Use asset inventory and criticality as inputs to risk decisions.
Use segmentation to reduce unnecessary connectivity and lateral movement.
Make remote vendor access explicit, controlled, and auditable.
Plan recovery around process dependencies and safe-state requirements, not only system restoration.
04 / Takeaways
What you'll learn
- OT asset inventory and ownership
- Criticality classification
- Zone and conduit architecture
- IT/OT DMZ patterns
- Secure remote access
- Monitoring and incident response
- Backup and recovery architecture
- Resilience and third-party risk
05 / A connected system
Architecture at a glance
- 01Enterprise IT
- 02Security controls
- 03IT/OT DMZ
- 04OT operations
- 05Control and field process
A controlled boundary separates enterprise and industrial environments. Monitoring and recovery controls span the architecture without bypassing site safety requirements.
06 / A phased approach
Implementation roadmap
- Weeks 1-3Asset and dependency discovery
- Weeks 4-5Criticality and risk assessment
- Weeks 6-8Target segmentation and remote-access design
- Weeks 9-12Control implementation and monitoring
- Weeks 13-16Recovery validation and operational handover
07 / For decision makers
Who should read this
- CIOs, CISOs, and CTOs
- OT and plant operations leaders
- Industrial infrastructure architects
- Cybersecurity and network security leaders
08 / Aidant IT relevance
Move from guidance to a plan
Aidant IT can support current-state assessment and architecture planning across infrastructure, security, resilience, and controlled connectivity, working with operational stakeholders to respect site constraints.
09 / Common questions
FAQs
Does this replace an OT safety assessment?
No. Cybersecurity architecture should complement, not replace, site safety engineering and operational controls.
Can the framework apply to hybrid IT/OT environments?
Yes. It is organized around trust boundaries, criticality, and operational context rather than one fixed topology.
What is the first practical step?
Establish a reliable asset inventory, ownership model, dependencies, and criticality classification.