fwupdateDownloader sample app

I was looking at the fwupdatedownloader sample app provided by Legato. The app listens on a socket and waits for a FOTA download file. But how would this work in the real world ? Does this work only over cell or would this work over Ethernet since most FX30s would be behind a NAT

I have modified the app as TCP server and tried in USB ECM interface, it was working fine:

You can set up TCP server on port 5000 by this nc binary to see if you can connect from outside:

chmod 777 ./nc
./nc -l -p 5000

nc (756.4 KB)