Proprietary LoRaWAN frames sequence

[pskifast]

Hi all!

I have an issue, which is similar to the one described here:

Echo on Rx when sending proprietary LoRa frames

Hi all, First thing first, thanks for this project. I’am using a Raspberry + RAK831 since some time now. GREAT piece of software. Shortly, I’am using the projet to construct a bridge between LoRaWan and our proprietary protocol (over LoRa). Every thing seems OK, but when I send my proprietary frame to: “gateway/my_gateway_ID/tx” I receive the frame sent on “gateway/my_gateway_ID/rx”. Is there a way to avoid echo ? Thanks, BR.

On regular intervals proprietary loarawan frames are getting logged on my gateway.
DOWNLINK gets registered first and after 2 seconds the UPLINK shows up.

Uplink has some base-64 content that I cannot find out how to decode. Strangely, both of them have the same mic!

Does anyone know what these are? Are they described somewhere in the Standard?

Thanks!

[brocaar]

Could it be that you have the gateway discovery feature enabled? You’ll find this under the network-server configuration.

This feature is sending a regular “ping” between the gateways, using the Proprietary message-type. The content is just a random token to correlate the “ping” that was sent with the gateways receiving the “ping”.

[pskifast]

@brocaar,
Yes, I have this feature enabled. Is this a proprietary implementation of the Chirpstack server, or is it something described in the Standard? Also, the ping originates from the AS or the NS?

Thanks!

[brocaar]

It is something which is not standardized. The ChirpStack AS sends this to the ChirpStack NS for transmission. You will find the code here: https://github.com/brocaar/chirpstack-application-server/tree/master/internal/gwping.