...
QoS 0, delivered at most once
QoS 1, delivered at least once
QoS 2, delivered exactly once
ClearBlade IoT Core does not support QoS 2. Publishing QoS 2 messages closes the connection, and subscribing to a predefined topic with QoS 2 downgrades the QoS level to QoS 1.
QoS 0 and 1 function as follows in ClearBlade IoT Core:
...