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.
• Using the Sparkplug B protocol provides the benefits of session management including Primary Host ID
• Understand 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. 

• 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.
• 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