Enqueueing device downlink payload with "devAddr" instead of "devEui" through Node-Red

[Lime_Ajinomoto]

Hello guys.

I am trying to send a downlink payload through Node-Red with the @chirpstack/node-red-contrib-chirpstack node, I was able to do that successfully by returning “devEui” to the device downlink node.

My question now is that would I be able to do the same with only “devAddr” (without “devEui”) using the same device downlink node? Is there a workaround of some sort?

(I tried & would only get “devEui is undefined” error.)

[Jerome73]

Hi ,
DevAddr can change, and therefore is not a valid “unique key” for api calls.
It is not predictable if you prefer.
I’m curious to understand why you are trying to do so…

[brocaar]

@Jerome73

DevAddr can change, and therefore is not a valid “unique key” for api calls.

It can change, but there can also be multiple devices using the same DevAddr. In such a case one DevAddr would point to multiple DevEUIs. As each DevEUI has its own device-session, ChirpStack will then validate the MIC against multiple sessions and find the correct DevEUI for the given uplink.

For downlink, this will not work.