Hi David,
you are right, that the UDP server of IoT Creators doesn’t send back an acknowledgment for a received messages.
BUT: The CoAP/Leul server of IoT Creators acknowledges a received messages with a “2.05 Content” acknowlegment.
Be aware that CoAP/Leul is the Huawei flavor of CoAP and it is supported by Huawei chipset such as HiSilicon which are used in moduls such ublox N211 or Quectel BC95.
For many customers it is not enough to have an acknowledgment between the device and the IoT middleware. The implement an asynchronous acknowledgment between the application and the device on the basis of a downlink message. If you would need the asynchnronous application acknowledgment it wouldn’t make a difference between CoAP/Leul and pure UDP.
Regards, Roland