@mfalkvidd: So you are right, requestEcho is the end-to-end echo parameter but end-to-end means something else what I thought.
Meanwhile I tested the other direction: controller (node-red) ->mqtt -> gateway -> sensor_node message sending with ack turned on in mqtt message. I found that in this direction the sensor node sends back echo automatically to the controller through gateway and through mqtt. So it is real (full) end-to-end echo If the controller sending command to my-sensor node, but it is not that if the node sends data to controller (in that case gateway sends back echo to node). I haven't found a description in documentation about this behavior. Is it planned to add this feature to tell the gateway to enable pass through echo request to controller? So communication in both direction whould be symmetric. Thanks!
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