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Say that you have 10,000 devices, each of which is connected to ClearBlade IoT Core over an MQTT connection. Even if the devices don't send telemetry events or state data over one month, they will still send PINGREQ messages to ClearBlade IoT Core to keep the MQTT connection alive. The PINGREQs’ frequency depends on each connection’s keep-alive value. Even though a PINGREQ may be only a few bytes, any messages smaller than 1024 bytes are still charged as they were 1024 bytes because it is the minimum data size used for billing.
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