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• MQTT V3.1.1
• we recommend using Paho library components http://www.eclipse.org/paho/
• The MQTT message payload can be zipped. zipped message should use the topic prefic "/application/gzip" (example: <orgShortName>/events/<serial>/application/gzip)

Topics/Message Types

From

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Edge Gateway to Cloud (publish)

Historical data

• synonym for values, measurements, readings...
•  we recommend to send historical data periodically

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• this sensor is used to display the gateway status
• the gateway should try after a successful connect to the MQTT Broker this message. Only by successfully receiving the acknoledgement it can be assured that next messages can be published. (access security might appear)
• use events with state: "CONNECTED" 
• on a regular shutdown of the gateway we recommend publishing a state: "OFFLINE" event
• in order to show a unexpected disconnect we recommend using the MQTT feature lastWillTestament (using an offline payload)
• the timezone information of the timestamp of the CONNECTED message is used to 

System Messages

Topic: <orgShortName>/sys_msg/<serial>

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Topic: <orgShortName>/imgdata/<serial>

open

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From Cloud to Edge gateway (subscribe)

Actions

• to trigger any action from the ACP the actions have to be defined first (see templates) 

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