Does TTN support LoRaWan 1.1 DeviceTimeReq?


(Aa) #1

It is really hard to find the answer to a simple question. It looks like LoRaWan 1.1 DeviceTimeReq is supported for the paid service (things industries), but it is not available for TTN, is this true?


(Jac Kersing) #2

Where did you find the current TTN deployment supports LoRaWAN 1.1? The V3 announcement mentions that will support 1.1


(Msegura) #3

Any update about time sync of end nodes ?
Is there any way to do it without DeviceTimeReq, until V3 will be finally released?


#4

LoRaWAN 1.1 will be supported with V3 network server which is in the works. I hope it supports DeviceTimeReq and I think it will.
I think there are 2 other methods that you can use but I haven’t used them myself and I don’t know if TTN/TTI supports it. It’s called:

Application layer clock synchronization over LoRaWAN
Recommended Practice Document

But is says this:
An end-device using LoRaWAN 1.1 or above SHOULD use DeviceTimeReq MAC command instead of this package.

So that’s why I’m waiting for DeviceTimeReq instead of implementing this other method.


(Jac Kersing) #5

Implement it as part of the application layer. Have your node send a special packet to your application and have that answer with the current time. A downlink packet should be at the node in either 1 (RX1) or 2 (RX2) seconds, add logic (at the node) to determine if it was received in RX1 or RX2 and you have a pretty accurate sync.


(Aa) #6

so it’s implemented yet? i think you have to use a special mac command to get the time sync to work. ttn really behind the ball these days