there are at least two different systems. The system commonly used in DL and OE uses these parameters:

Frequency: 433,775 MHz
Spreading Factor: 12
Bandwidth: 125kHz
Coding Rate4: 5\ CRC enabled

The LoRa header consists of 3 bytes: „< FF 01“, followed by a standard APRS record as in this example:

DJ0ABR-7>APLT00,WIDE1-1:!4849.27N/01307.72E[/A=001421LoRa Tracker

the record consists of Source>Path,Destination:
Once the record is received by an iGate, the iGate completes the path and destination as follows:

DJ0ABR-7>APLT00,WIDE1-1,qAO,DB0SL-10:!4849.27N/01307.72E[/A=001421LoRa Tracker

The source is delimited with the > character and path/destination with the colon. After that comes the APRS info as described in the APRS specification.