Double or missing packets

  • I’m building an IoT device that sends data to my server every 30 minutes. For this, I use a BK7020 on the T-Mobile network. The problem is, very often a lot of packets in a row don’t ever arrive at our server.
    Then, sometimes a packet arrive two times, despite the function that sends data really only being called once. I have tried this with multiple BK7020’s, all have the same problem. The BK7020 doesn’t give me any error codes, and just returns an OK. I have added capacitors according to the BK7020’s documentation.

    So, I am 100% sure I’m only telling my SIM Modem thing (the BK7020) to send the packet once. I am also 100% sure the packet sometimes arrives twice, with like one or two minutes inbetween. Could this be an error on the side of T-mobile? Or is it more likely internal fuckery of my BK-7020?

    I should probably look into this myself, so would setting up AllThingsTalk be a productive way to help debug this? If not, do you have any other suggestions? The API is still opaque wizardry to me, but I’m willing to invest a couple of days to figure it out if that would help.

    With kind regards,

  • @Sopwafel Hi, please make sure you are running the latest FW. Have you tried with a different modem? The SIMCOM 7020 is quite old…

  • @Stefan-de-Lange Thanks for the suggestion! Both things I hadn’t considered yet. Will be looking into them.

  • Deutsche Telekom IoT

    @IoT-Arista and @Sopwafel,
    If you still encounter problems, I can try to investigate for you in the platform whether the subscriptions to your data contain any errors.
    You can send me a direct message or a mail to our mailbox with the device and account details.