I'm not sure how to describe what I'm looking for. I'm working on Linux.
I have a remote device with a 4G SIM card which I need to connect to by dialing in and then running some commands over the resulting serial connection. However, I don't have a local modem to do the testing, and it looks like all the mobile phones I have access to cannot work as modems (perhaps I'm not doing it correctly; I'm using the usbserial module and I don't see any /dev/ttyUSB* or /dev/ttyACM* device appear).
Is there some service (public, paid or otherwise) that would allow me to create a virtual serial device over which I could place calls to the 4G network?
Edit: ok, perhaps it's not 4G (I'm not sure about the exact network it uses), but it's definitely something one dials into.