Time in Application vs Gatewaytime console


#1

I try to undertand times logged in the Gateway Console and in the application (through MQTT integration),
to be able to do subsecond timemeasurement, but sofar i dont.

In the TTN Gatewayconsole i find a timestamp of my gateway (kerlink) , the plain string in GMT, passed by the packetforwarder.to TTN.
My Gateway may be not perfectly synced, so that we get the starttime in TTN domain which has a a 500 ms differnt time is understandable.

However,sofar i am not able to explain the timedifference in the application gatewaydata time and the gateway console output.

suggestions ?

Thanks
Walter Takens

=========================================================================
Things Gateway Traffic

{
“gw_id”: “eui-024b08fefe040083”,
“payload”: “QAoUASYAUwABps7v7s1pncUF”,
“f_cnt”: 83,
“lora”: {
“spreading_factor”: 12,
“bandwidth”: 125,
“air_time”: 1318912000
},
“coding_rate”: “4/5”,
“timestamp”: “2018-07-11T13:02:27.826Z”,
“rssi”: -73,
“snr”: 6.8,
“dev_addr”: “2601140A”,
“frequency”: 868500000
}

Trace:
start 7/11/2018 15:02:27:258048
0 ms bridge “ttn-bridge-eu” receive
0.03 ms bridge “ttn-bridge-eu” forward
1.1 ms router router ttn-router-eu" receive
1.39 ms router router ttn-router-eu" build downlink
1.42 ms router ttn-router-eu forward

=========================================================================
Application MQTT integration:

{“app_id”:“gps”,“dev_id”:“edgetest1”,“hardware_serial”:“00914DFC4B7CFAAF”,“port”:1,“counter”:83,“payload_raw”:“AAF8FwA=”,
“metadata”:{“time”:“2018-07-11T13:02:27.821550457Z”,“frequency”:868.5,“modulation”:“LORA”,“data_rate”:“SF12BW125”,“airtime”:1318912000,“coding_rate”:“4/5”,"
gateways":[
{“gtw_id”:“eui-024b08fefe040083”,“timestamp”:1811383788,“time”:“2018-07 11T13:02:27.772791Z”,“channel”:2,“rssi”:-73,“snr”:6.8,“rf_chain”:1,“latitude”:52.00996,“longitude”:4.71591,“altitude”:7},