The duty cycle limitations in the LoRaWAN specifications are indeed a bit unclear. It’s important to keep in mind that the duty cycle limitations described in the tables of the specifications are LoRaWAN-imposed limitations, and not legal limitations. If you build commercial devices and want them to be LoRaWAN certified, they need to comply with the specification. Development devices don’t have to be fully compliant with the specification. Any device (whether LoRaWAN or not, gateway or node, commercial or development) needs to be compliant with the legal limitations that apply in your country.
So to answer your questions:
- The LoRaWAN-imposed duty cycle limitation applies to these two channels. The specification does not say anything about duty cycles on other channels. The regulatory duty cycle limitations typically apply to an entire frequency band, so make sure to check with your national regulator what is allowed or not.
- The LoRaWAN-imposed duty cycle applies to nodes only. Gateways are technically just LoRa devices, not LoRaWAN, so the LoRaWAN specification doesn’t apply to them. The regulatory duty cycle limitations typically apply to any transmitter.
- End devices need to implement and enforce the limitations in order to get certified. Gateways handle this differently, which is why the network (the Router of our v2 stack and the Gateway Server of The Things Stack) also enforces these limitations.