LTE NB-IoT with NIDD (Non-IP Data Delivery) ???
Does any of the LTE boards support Non-IP bearers for NIDD? Are there any samples or guides?
Background: low bandwidth LTE CAT NB1 is nice, but the overhead of TCP for sending very small data packets is just not tolerable (100 bytes of real payload can use up to 1Kbyte of network traffic under bad conditions). Add TLS that to that and you easily end up with 4Kbyte for 100 byte payload. Not only uses that mouch data volume, it also uses to much power to send the data. This means that anything over TCP (e.g. MQTT) is out.
The solution in the 3GPP world is NIDD (Non-IP bearers) and other CIoT optimizations. I can't find anything about support for those 3GPP features in the documentation.
NIDD is one of the transport layer supported by LwM2M, this will let you work with higher layers and minimize your payload. Although it refers to NB-IoT, you might want to give a look at the discussion, we had with Deutsche Telekom back in June: https://ioterop.com/nb-iot-webinar/
Note that for a correct comparison IP vs NIDD, you may want to test CoAP/DTLS with Continuation Identifier (CID), before getting rid of IP. CID gets you rid of authentication. See below.