Hi and thank you again @kersing,
No, my payloads are binary; 1 or 5 bytes for downlinks and 5 bytes for uplinks.
Ah, so when you say send a “small” correlation id you mean I should add my own as part of the payload!
So, in a typical uplink MQTT msg, I might see these correlation ids:
"correlation_ids": [
"as:up:01GNATSVGD3FHJF0W9M1RHR5NX",
...
"rpc:/ttn.lorawan.v3.NsAs/HandleUplink:01GNATSVGCH0YZVYA4FRMEJNHR"
]
I take it the as:up: is generated by the application server and is for internal TTx use? I don’t really see the point of sending custom correlation ids in downlinks only then, as referenced in MQTT Server | The Things Stack for LoRaWAN
The Things Stack supports some cool features, such as confirmed downlink with your own correlation IDs. For example, you can push this:
```
{
- “downlinks”: [{*
- “f_port”: 15,*
- “frm_payload”: “vu8=”,*
- “priority”: “HIGH”,*
- “confirmed”: true,*
- “correlation_ids”: [“my-correlation-id”]*
- }]*
}
```
But do either of you know what @htdvisser meant by his comment:
It is possible for a user to schedule a downlink with correlation ID as:up:trololololo
. If that downlink is acknowledged by their end device, you may receive that correlation ID in your uplink.?
It seems to imply you will see your as:uptrololololo in an uplink which I have seen neither for confirmed nor unconfirmed uplinks?
@Johan_Scheepers - my application is a metered electricity dispenser. And there haven’t been any uplinks for me to read off the RSSI and SNR for a while on the unreliable nodes, the console has refreshed itself. I am not sure of the distance for any particular node. What RSSI, SNR might you look for to get reliable messaging? But please don’t spend your time on this, I can research that in the forums.
I was trying to understand the best way to associate pairs of downlinks and uplinks before looking at reception. And for that it seems I might be able to use fcnts for this purpose rather than a) using default correlation ids, or b) embedding custom cids as part of the end device payloads.
Thanks,
Chris