I have a USB modem detected as a device device file (
/dev/ttyACM0). Redirecting AT commands to the device file seems to work as the modem responds.
Am going with the following assumption, the upper part represents a control channel. Through it one can dial up, setup the modem, cancel the connection... in general do things related to controlling the modem without actually handling the
data I mean everything that aren't controls (for example HTTP packets).
Where does the data flow happen? If it's through the same file, how is that multiplexed?
Also ideally, one would like the modem just to be an underlying "service" that provides a network interface with an IP, so one can abstract that out and use TCP/IP sockets. The sockets are implemented in the kernel.
How does this fit into the picture once the modem is exposed as
/dev/ttyACM0 in user space?