I am working on a project based on the Arm Mbed LoRaWAN example, which uses unconfirmed uplinks. To my knowledge, unconfirmed uplinks should not be acknowledged by the receiver, as stated in Section 4.2.1.2 in LoRaWAN L2 1.0.4 Specification.
I noticed in my backend (using ChirpStack) that once a message was sent, it receives an UnconfirmedDataDown. So my question is if the spec states that it shouldn’t be acknowledged, then why does my gateway (running LoRa Basics Station) respond to an UnconfirmedDataUp with an UnconfirmedDataDown?