> It is often seen as more cost-effective to purchase a cellular modem with an internal MCU rather than a separate cellular modem and a host MCU to run the netw

> It is often seen as more cost-effective to purchase a cellular modem with an internal MCU rather than a separate cellular modem and a host MCU to run the networking stack. This one isn't just cost--the compliance restrictions that the cellular carriers place on you are idiotic. The big one we bumped into is "must allow allow carrier initiated firmware updates with no restrictions on scheduling" which translates to "the carrier will eat your battery often and without warning". In addition, many IoT devices may not call home more than once every couple of months. And the carrier will happily roll out tower firmware that will kill those being able to call home. If I use a module with my own firmware, the modem folks will simply point fingers at me. If I use a module with integrated SoC and firmware and it gets updeathed, I get the "joy" of yelling at the cellular module manufacturer. (I had the wonderful experience of watching a cellular IoT project go gradually dead over 3 days as the carrier rolled out an "upgrade" across its system. We got a front seat as the module manufacturer was screaming bloody murder at the carrier who simply did "We Don't Care. We Don't Have To. We're the Phone Company.")