Troubleshooting packetloss

Question

Hi all,

I'm facing an issue, some frame are not received and can come from any device, I have 2 GW, one RAK and one Chirpstack/raspberry, the RAK is LTE (UDP forwarder) and the chirpstack is over ethernet/fiber (in MQTT), each message received I can see the 2 GW, but over 1/1000 more or less messages, there is missing message.
The 2 GW are 5 meters far from each other.
From my point of view, it is coming from the server or an interference, I don't see a problem of backhaul, there are different, and from the server, strange because it is coming from UDP forwarder and MQTT.
I don't know how to continue investigations...

Orne Brocaar · Answer

Please note that there is no guarantee that LoRaWAN messages are received by a gateway. The radio spectrum is shared and interference from other radios could cause packet-loss on uplink / downlink transmissions. This is not handled by the LoRaWAN protocol. You could use a Confirmed Uplink to receive an ACK indicating the uplink was received by the NS, but this would cause other issues (as it will require a downlink transmission for each uplink). In case only one of the two gateways is reporting the uplink, it could also mean that the other one was in TX mode, meaning it was not able to receive anything at that given moment (assuming your gateways are half-duplex).

Troubleshooting packetloss

1 Answers