Industrial MQTT: topics, QoS and the data contract
Go beyond connecting to a broker. Make message meaning, duplication and freshness explicit and manageable.
Read the guideSolutions
Industrial IoT & MQTT
Make shop-floor data ready to share.
IT/OT architects and system integrators
Transfer production data to central applications using a controlled topic and payload structure. Design MQTT, REST and supported cloud connections while preserving data age and quality.
SourceOPC UA / SQL
OPC RouterConnect · Transform · TransferDestinationMQTT / REST / cloud
Typical data points
- Measurement value, unit and quality
- Source timestamp
- Equipment and site hierarchy
- State and alarm events
- Connection status (online/offline)
How the flow works
- Connect
Values are read from the source (OPC UA or SQL) and triggered on a change condition.
- Transform
Values are converted to the defined JSON schema; topic hierarchy, unit and timestamp are added.
- Transfer
They are published to target applications over MQTT, REST or a suitable cloud connection; outage behaviour is planned with QoS and a buffer.
Decisions before connecting
- 01Broker and topic permissions
- 02JSON schema and version
- 03QoS and duplicate handling
- 04Outage buffer and timestamps
Pilot acceptance criterion
Measure record counts, duplicates and message age during broker outages and reconnection.
Connectors used in this scenario
Connector availability, version compatibility and licence scope are verified for each project.
Implementation guide
Frequently asked questions
Which topic structure should I use?
A fixed hierarchy that runs from general to specific is recommended (for example site/area/line/equipment/measurement). The MQTT topic builder generates sample structures and subscription filters; see MQTT in production for detail.
Is data lost if the broker goes down?
Behaviour depends on the QoS level, session settings and client-side buffering; there is no unconditional guarantee. Acceptance tests measure record counts and duplicates during a broker outage and reconnect. See the Store & Forward guide.
Your next step
Let’s talk about the systems you need to connect.
Share your source, destination and intended outcome. We’ll help define the project scope.