List of Documents and Drawings Required for OT Network Projects – From Design to Commissioning
Operational Technology (OT) networks are the backbone of industrial automation systems. Whether it’s a new greenfield plant or a brownfield upgrade, proper documentation is essential throughout every phase of the project lifecycle—from concept design to commissioning. In this guide, we’ll walk through the comprehensive list of documents and drawings required for an OT network project, ensuring alignment with engineering, cybersecurity, regulatory, and operational best practices.
Why Documentation Matters in OT Projects
Thorough documentation ensures:
- Clear communication between stakeholders
- Compliance with standards (e.g., IEC 62443, NIST 800-82)
- Efficient troubleshooting and maintenance
- Security through visibility and change control
- Faster commissioning and validation
Project Lifecycle Overview for OT Networks
- Design/Engineering Stage
- Procurement/Construction Stage
- Configuration & Integration
- Commissioning & Handover
Each phase involves specific sets of documents and drawings.
Design Stage – Core Engineering Deliverables
1. OT Network Architecture Diagram
A high-level logical diagram showing:
- Zone and conduit segregation (per IEC 62443)
- Firewalls, DMZ, and segmentation
- Core, distribution, and access layers
2. Network Topology Drawing
Physical layout showing:
- Switches, routers, firewalls, and servers
- Patch panels, field panels, and rack locations
- Fiber/copper paths, media converters, VLAN mapping
3. IP Addressing & Subnet Allocation
Detailed Excel or Visio file listing:
- All device IPs by VLAN/subnet
- Address reservation for future expansion
- Redundant path details
4. Device Specifications & Bill of Materials (BoM)
Includes:
- Switches (DIN rail, rack mount, PoE, etc.)
- Firewalls (e.g., Tofino, FortiGate, etc.)
- UPS systems, industrial PCs
5. Network Segmentation Plan
Defined per zone (Control, Safety, DMZ, Business), and communication rules with:
- VLAN IDs
- Firewall rules
- Trust boundaries
6. Cable Schedule
Lists:
- All copper and fiber optic cable types
- Termination ends (source to destination)
- Tagging convention
Procurement & Construction Stage
7. Rack Layout / Panel GA Drawing
Visual layout for each cabinet:
- Device mounting
- Power supply routing
- Cable ducts and labeling zones
8. Loop Drawings / Wiring Diagrams
Includes detailed interconnection of:
- I/O to PLC
- PLC to switch
- Redundant paths to SCADA or DCS
9. Equipment Datasheets
Factory datasheets for each device confirming:
- Model number
- Firmware compatibility
- Compliance standards (UL, CE, etc.)
Configuration & Integration Stage
10. OT Device Configuration Files
All programmed and saved configurations for:
- Switches (e.g., VLANs, trunk, spanning-tree, SNMP)
- Firewalls (e.g., rules, zones, NAT policies)
- Wireless controllers
11. System Integration Checklist
Step-by-step integration log:
- Ping & connectivity checks
- Routing tests
- Firewall traffic simulation
12. FAT/SAT Protocol Templates
Factory Acceptance Test (FAT) and Site Acceptance Test (SAT) procedures:
- With expected vs actual results
- Firmware checks
- Interface integrity
Commissioning & Handover Stage
13. As-Built Drawings
Updated layout and schematics reflecting:
- Final equipment installation
- Cable routing changes
- Panel modifications
14. Final IP Addressing Scheme
Reflecting any:
- Added/removed devices
- Actual physical ports used
- Last-minute network changes
15. Network Validation Report
Contains:
- Port status summary
- VLAN & routing table screenshots
- Cybersecurity configuration verification
16. OT System Handover Document
Includes:
- Credentials (in sealed envelope or vault)
- Firmware backup (USB/Cloud)
- Configuration snapshots
- Maintenance contact list
Optional (But Recommended) Documents
– OT Cybersecurity Risk Assessment
Performed during design:
- Identifies vulnerabilities
- Recommends mitigations (e.g., unidirectional gateways, air gaps)
– NTP & Time Sync Design
Defines master clock, fallback strategies, and:
- IEEE 1588/PTP integration
- GPS sync design
– Backup and Restore Procedure
Offline and online backup process:
- Frequency of configuration saves
- Disaster recovery steps
Summary Table – OT Network Documentation Lifecycle
| Project Phase | Key Documents |
|---|---|
| Design | Architecture, Topology, IP Plan, Cable Schedule, BoM |
| Procurement | Panel Layout, Loop Drawings, Datasheets |
| Configuration | Config Files, Integration Checklist, FAT/SAT Templates |
| Commissioning | As-Built, Validation Report, Handover Docs |
Conclusion
A well-documented OT network is not just an engineering deliverable—it’s an operational asset. Proper documentation enables efficient troubleshooting, strengthens cybersecurity posture, and supports long-term scalability. From concept to commissioning, each document ensures visibility, consistency, and confidence for all project stakeholders.
“In OT, if it’s not documented—it doesn’t exist.”