A JSON body is encoded as defined for the JSON message mapping defined in 7.2.3.
A UADP body is encoded as defined for the UADP message mapping defined in 7.2.2.
It is expected that the software used to receive UADP NetworkMessage can process the body without needing to know how it was transported.
If the encoded MQTT message size exceeds the Broker limits it is broken into multiple chunks as described in 126.96.36.199.4.
It is recommended that the MetaDataQueueName as described in 188.8.131.52.6 is configured as a sub-topic of the related QueueName with the name $Metadata. The MQTT RETAIN flag shall be set for metadata messages.