Hey @afzal_m, Thanks for explaining. This helps. Please consider making this a protocol when sending out emails about service interruptions (planned or not). And please let us know what will happen with the sent data: Will devices need to send it again or will it arrive at our application after the update was successful? Once we know this, we can tell our customers what to expect and how to act on degraded functionality,

Currently the API supports the following for functions/URLs to send downlink messages to the device downlinkMsg/0/data Sends regular queued downlink messages to device when uplink is received. downlinkMsgBase64/0/data Sends queued binary data blob message to device when an uplink is received. The function expects base64 encoded payload from the applaction as input into this function. Before the message is sent to the device it is decoded back to binary and sent to the device. downlinkMsgDrx/0/data Same like downlinkMsg/0/data but without queuing. downlinkMsgBase64Drx/0/data Same like downlinkMsgBase64/0/data but without queuing.

@Eric-Barten said in Downlink API dataformat: ary the device visualizes the received data for yo Okay, that my bad. Thanks for the answer

@David-Netten 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 ​

@lbr hi, if you still have problems please contact me via support@iotcreators.com and provide me your imei. I will help you. Regards, Roland

@afzal_m Yes, I tried it few minutes before you wrote here and it works! Thank you very much, we can continue in our small project…

Thanks. We’re checking again. Get back to you soon…

I found the problem, I use an arduino leonardo with a dragino nbiot shield. For incomming/outgoing messages i use SoftwareSerial.h, to change the tx/rx pins to pins 10/11. I fixed the problem by using the normal rx/tx pins and it works. Hence the library seems to be my problem. Hope this helps anyone.

There is no option to query the status of a downlink message. Buffering of downlink messages may occur on different places in our solution it is hard to give an clear response to such a request due to the asynchronous nature of the protocols. Note: after sending an uplink message we will try to downlink all buffered messages.

@sopwafel You could, but be aware of using PSM and expected latency. Your device might be sleeping again before it had the chance to receive a downlink message. I don’t know if it’s possible to use in combination with the T-Mobile CDP but you might want to take a look at LWM2M and CoAP. These protocols have acknowledgements build in.

The term “latency” relates to one-way, downlink or uplink communication. It does not include the time needed to establish a connection between the server and the device. If the device is in power saving mode, it will only receive or send data after it wakes up. According to measurements on current test setups with pre-commercial radio modules, data transmissions typically exhibit a latency of less than a second. In scenarios involving deployments in poor coverage areas, latency may increase up to 7-10 seconds. That said, NB-IoT technology is continuously being enhanced, so current figures are expected to improve with successive releases of the specification.

NB-IoT supports bidirectional communication, but the more common direction is uplink transmission. Only half-duplex is supported, i.e. uplink and downlink don’t take part simultaneously. UL peak rate up to 230 kbps DL peak rate up to 250 kbps Please note that these are not the datarates meanwhile. Current datarates are maximum 20Kbps UL/DL due to single tone transmission.

Does it also work for @trick2011 now?