What is an Asset Inventory?
An Asset Inventory is an overview of all systems, devices, software and components present within an organisation — both physical and digital.
It forms the basis for Cybersecurity, risk management and operational management: you can only secure what you know about.
A good asset inventory captures information on both IT assets (such as servers, laptops and switches) and OT assets (such as PLCs, SCADA, HMIs, Sensors and Actuators).
🎯 Why is an Asset Inventory important?
- Insight into vulnerabilities (e.g. via CVE, Vulnerability Management)
- Faster detection of unauthorised devices (rogue devices)
- Foundation for segmentation and access management
- Required for compliance with standards such as NIS2, IEC 62443 and ISO 27001
- More efficient management and maintenance of systems
- Preparation for incident response, audits or changes
📦 What does a good Asset Inventory contain?
| Attribute | Example |
|---|---|
| Asset name | PLC_Bottling_Line3 |
| Type | PLC, server, switch, workstation |
| Location | Hall A, server room 1 |
| IP/MAC address | 192.168.1.22 / 00:0C:29:3E:2A:5F |
| Firmware/OS | Siemens TIA Portal V16, Windows 10 |
| Status | Active, under maintenance, decommissioned |
| Criticality | High / Medium / Low |
| Network segment | OT-vlan-03, DMZ, guest network |
| Serial number / LOT | 12345-PLCB-XY99 |
🔍 How do you build an Asset Inventory?
- Scan the networks (using NMAP, OT discovery tools)
- Import existing CMDB or Excel lists
- Automatic detection through agents or passive monitoring
- Manual addition of assets that cannot be discovered over the network
- Classify by type, location, function and criticality
- Update continuously when new projects or changes occur (MOC)
🛠️ Tools for Asset Inventory
| Tool / method | Use |
|---|---|
| OT: Claroty, Nozomi, Dragos | Passive asset discovery in industrial networks |
| IT: Lansweeper, Qualys, Tenable | Active scanning, CMDB integration |
| SIEM / SOC integration | Real-time updates and correlation with incidents |
| Manual (Excel, CMDB) | Starting point for smaller environments |
🔐 Asset Inventory and cybersecurity
An up-to-date overview is essential for:
- Patch management & vulnerability detection
- Network segmentation in line with the zone and conduits model
- Incident Response & forensic investigation
- Assigning Security Levels (SL) per IEC 62443
- Management of Remote Access, VPN and Jump Server
✅ Benefits of a sound Asset Inventory
- Complete view of your digital attack surface
- Faster detection of anomalies or new devices
- Better collaboration between IT, OT, maintenance and security
- Required foundation for many standards and audits
- Helps prevent downtime and accelerate recovery
📌 In summary
An Asset Inventory is the fundamental list of all systems, devices and components within your IT and OT. Without current and reliable asset data, you cannot deliver effective security, Monitoring or risk management.