Simply put, metadata is data about data. It describes and provides information about other data.
In the context of “Discovering asset metadata of OT devices,” we are talking about metadata within operational devices that reside on SCADA networks, DCS networks, or OT networks as a whole. Take for example an Allen-Bradley PLC. Metadata about this type of device may simply be its make, model, and its manufacturer. A step deeper, and we may find metadata about its IP and MAC address, its OS and build numbers, as well as data around potential software flaws.
A step even deeper may reveal:
Connections these devices are making to peer devices
Ports and protocols in use
Services being leveraged to make these connections
Activities and commands used to control and configure these devices
Put into practice, properly tracking and reporting on metadata about a controller and its fans’ revolution speed may reveal an anomaly that would have left a critical system in jeopardy. The metadata in this instance is the hidden detail found when examining actual revolutions per second, and their deviations from normal. What may not be visible to the naked eye is clearly apparent when examining the metadata.