Transmitters

A Transmitter is an agent that monitor tags, converts them to Sparkplug Messages, and publishes to an MQTT Server. 

• Messages can be consumed by any Sparkplug Host Application such as MQTT Engine.
• Any MQTT client created by the agent will publish and subscribe to data using the Sparkplug B protocol.
  • Uses the namespace spBv1.0
  • Using the Sparkplug B protocol provides the benefits of session management including Primary Host ID
  • Understands Ignition UDTs and can be configured to publish UDT definitions in BIRTH messages
  • Is capable of publishing 10s of thousands data messages contain multiple tag change events

UNS Transmitters

A UNS Transmitter is an agent that monitors tags and publishes them as MQTT Messages with a JSON payload to an MQTT Server. 

The UNS Transmitter would be configured to read tags from a UNS structure, such as created by MQTT Engine, and publish tag changes over MQTT to any Enterprise consuming clients.

• Messages can be consumed by any MQTT client that can parse JSON messages.
• Any MQTT client created by the agent will only publish data using the MQTT protocol.
  • Uses the namespace unsAv1.0 (which can be disabled)
  • Publishes a single data message for each tag when QualifiedValue of the tag changes 
  • Publishes a single properties message is published for each tag on every client connection
  • Publishes the leaf tags of Ignition UDTs and the structure of the UDT (i.e. UDT name itself and folders in the UDT) become topic tokens.

Always less efficient than Sparkplug - orders of magnitude less