Cybersecurity
Asset Inventory
You cannot protect what you have not listed.
Written guides in this section
Full references, procedures, and diagnostic guides published under Asset Inventory.
Building an OT Asset Inventory
The list of everything in the control system with a network interface or a program, and how to build one that is right: what counts, the fields to record, the site walk, the switch tables and passive listening that find the rest, and keeping it current.
9 min readUpdated Sep 5, 2026
Passive Discovery
Finding out what is on a control network by listening rather than probing: why active scans are risky around older controllers, how a mirror port feeds a sensor, what the traffic reveals, the blind spots, and how the sensor becomes continuous monitoring.
8 min readUpdated Sep 5, 2026
Documenting Firmware Versions
Why the firmware version of every controller, module, drive, switch, radio, and instrument belongs in the inventory with the date it was read: advisories are issued by version. Where to read each one, the several versions one controller has, and the cadence.
8 min readUpdated Sep 5, 2026
Topics in this area
Building An OT Asset Inventory
Building An OT Asset Inventory — practical reference notes for controls engineers, integrators, and technicians working with asset inventory.
Passive Discovery
Passive Discovery — practical reference notes for controls engineers, integrators, and technicians working with asset inventory.
Documenting Firmware Versions
Documenting Firmware Versions — practical reference notes for controls engineers, integrators, and technicians working with asset inventory.
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