Downlink Flow.md

Sending Downlink Messages

What happens after we receives a request from application layer

Validate request

TBD

• generate response for application layer

Translate request content to device packet:

• Packet layout
• Command codes and parameters
• All data in little endien

// TODO: examples

Wrap the device packet to MQTT payload

• Format: https://github.com/brocaar/lora-app-server/blob/master/docs/mqtt-topics.md
• Set the value of reference file to config_id from request
• base64 encode the entire packet, pack into the data field

{
    "reference": [config_id],                  // reference which will be used on ack or error (this can be a random string)
    "confirmed": true,                        // whether the payload must be sent as confirmed data down or not
    "fPort": 10,                              // FPort to use (must be > 0)
    "data": [encoded device packet]                          // base64 encoded data (plaintext, will be encrypted by LoRa Server)
}

Pulish to mqtt with the topic:

application/[applicationID]/node/[devEUI]/tx

Getting Acknowledgement

How can we make sure the device actually gets what we send, and does the command we sent take effect

Device received

Device executed the command