Issues connecting to cloud with NB-IoT

RE: Issues connecting to cloud with NB-IoT

Markus Tacker (he/him) — Thu, 07 Apr 2022 08:02:44 GMT

Well, regular Smartphone SIMs are not officially supported, you need a dedicated IoT SIM. You are entering undefined territory so there are many things that can go wrong. You could have a look at the modem traces to figure out what's going wrong.

RE: Issues connecting to cloud with NB-IoT

Baowz — Wed, 06 Apr 2022 15:16:01 GMT

Okay, that makes sense. Thank you for the answer!

I have another question as well if you don't mind:
On the prototypes we have running in Norway we are using "normal" phone sim-cards which probably use LTE instead of LTE-M. As mentioned above everything is operating as normal. How it basically works is that every 5 minutes the sensor sends data to AWS. However, every now and then we see the sensor skipping an interval and waiting 11-14 minutes instead 5 minutes. Our theory here is that it has disconnected from the network and then after some time reconnects. But we are very uncertain about the cause of this? The sensors are placed rather close to the city center of Trondheim, so the connection should not be an issue here. Do you have any thoughts about this?

RE: Issues connecting to cloud with NB-IoT

Markus Tacker (he/him) — Wed, 06 Apr 2022 07:52:56 GMT

NB-IoT networks typically do not support TCP connections, they only provide UDP. Therefore you won't be able to make an MQTT connection in such a network (MQTT depends on TCP for flow control).