Ping on Dragino


(Felipe Robles) #1

Hello everyone,

I wanted to know if there is some info or if is it possible to do a sort of a PING in the END-Device (Dragino shield), I want to know how much time does it take to send a packet from an End-Device and receive a response from the TTN.

Regards
F.


(Arjan) #2

Alternatively: just calculate it. The air time is also shown in TTN Console.

Next, for LoRaWAN Class A devices, the optional response will be after either a delay of exactly RX1 or RX2, hence after 1 or 2 seconds for a regular downlink…

Note that TTN will not send a response for every transmission. (LoRaWAN is not some TCP/IP; only downlinks, including OTAA Join Accepts and ACKs for confirmed uplinks, will yield responses. Most transmissions are just “fire and forget”, hoping that one or more gateways will pick it up and forward it to TTN.)


(Felipe Robles) #3

Thank you!

One question, how can I have an ACK for a confirmed uplink? because If I manage to get a confirmation for a uplink somehow I could extract the time it took for when I sent the uplink until I received the ACK.


(Arjan) #4

By definition, that time is always 1 or 2 seconds, and mostly depends on the preference of TTN.

(If your own code can somehow know if an ACK was received depends on the library you’re using. A good library will just re-send the message if no ACK is received, without bothering your own code with that, hence might not even make that information available to you…)

Note that TTN Console will also show the ACKs and retries.


(Ud Lo Ra) #5

If you are trying to evaluate the time for measuring the distance, search for “LoRaWAN localization/geolocation” on this forum.