Firmware WiFi Data usage

cchakons

Hello everyone,

I'm building a low data IoT device, it calls an API around 100 times a day. A single API call consumes around 500 bytes (see details on how I measured this below). My expectation is that the daily consumption (in KB) is 500 bytes * 100 / 1024 = ~49KB for 100 API calls.

To my surprise, after one day of testing, the device used around 1.5MB-2MB. This is way too much compared to my expectation. My device uses a SIM card so I really have to keep the data usage as low as possible.

I'm suspecting the m5stack firmware is sending some telemetry by default. This makes sense because when I look at UiFlow 2.0, and I click on available devices, I can see that UiFlow know if the device is Online or not. That means at least there is some keepalive call is being done to M5Stack servers for this.

Then I created a simple application that just connects to the WiFi router and just blinks the RGB LED, without any WiFi or internet access, and after some time (few minutes) I see data being used, 30KBs.

Questions
Has anyone else seen this same issue?
And do you know what's the best way to handle it?

Details on how I measured my API usage:

I measured my API call data usage using CURL and a few options to extract the data usage and request/response trace, and the call is around 500 bytes

curl -X POST "http://0.0.0.0:8000/api/example” -H "Authorization: Bearer MY_API_KEY" --write-out "\nSize of response body: %{size_download} bytes\nSize of request body: %{size_upload} bytes\n" --trace curl_trace.log -o /dev/null \ -s

Output:

Size of response: 16 bytes
Size of request: 0 bytes

From the curl_trace.log file the total size estimate:

* Request headers: 174 bytes
* Response headers: 317 bytes
* Response body: 16 bytes
* Thus, the total size for the transaction is:
	174 + 317 + 16 = 507 bytes

Device: Atom S3 Lite
Firmware: v2.1.3-ATOMS3-LITE
Language: MicroPython

Thanks,
Carlos

kuriko

Hi @cchakons
As you said, the UiFlow firmware will periodically send heartbeat packets to the server to ensure that the device is online, and sometimes synchronize some information. Please forgive me I can't provide you precise parameters.
UiFlow is just an easy-to-use development platform. If you want to accurately control these parameters, it is recommended to use traditional programming methods such as Arduino IDE or ESP-IDF.

ajb2k3

@cchakons is the packet sent increasing with each transmission? It could also be the buffer is not being emptied and it’s sending the buffer consisting of old and new data

cchakons

@ajb2k3 said in Firmware WiFi Data usage:

@cchakons is the packet sent increasing with each transmission? It could also be the buffer is not being emptied and it’s sending the buffer consisting of old and new data

@ajb2k3 its actually consuming data even if I am just toggling the RGB LED. So, its all coming from the UiFlow firmware.

@kuriko
I have a pretty functional code already in MicroPython so it would be nice if the M5stack Team can provide a way to disable WiFi usage by their firmware. If not I'm going to have to migrate all my code to C.