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

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 can be configured to read tags from the UNS structure 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
  • A single data message is published for each tag when QualifiedValue of the tag changes 
  • A single properties message is published for each tag on every client connection
• Has no concept of Ignition UDTs