MQTT, Publisher

MQTT, Publisher supports the connection to an MQTT broker. The change of data is only published, i.e. sent to the MQTT-Broker, but no data is received from the MQTT-Broker.

Supported versions:

• MQTT V3.1
• MQTT V3.1.1

Transport Layer:

• TCP/IP with or without TLS (configurable)

Security mechanisms:

• Authentication with user and password
• Usage of X.509 certificates

Predefined profiles for cloud services connectivity:

• AZURE IOT hub with X.509 certificates
• AMAZON AWS with X.509 certificates

Data processing:

• Supported QoS 0,1,2
• Data encoding in JSON
• Grouped / individual transmission of data changes

Operating mode

The current process image is written during startup or when the connection is interrupted, i.e. the current values of all configured data points are sent to the database.

After the initialization of the process image, only data point changes are written. Optionally, data point changes can be buffered if the connection is lost.

All data point entries have the following attributes:

• Timestamp
• Value
• Quality
• Data point type
• Data point designation
• Transmission direction
• Module or protocol stack