"Yes, there are standards. But as we all know, given 10 people
and a standard, you’ll end the day with 12 or 13 differently
behaving "standards-compliant" implementations. People suck. You'd
think it would be easy to agree on an AT command for "prefer 3G /
prefer 2G / 3G only / 2G only". NO SIMPLE FOR YOU. But
NetworkManager has to work around huge amounts of stupid.
Here’s a run-down of some of the mobile broadband hardware
that’s available today and what about it sucks.
"HUAWEI (PHEAR THE DRAGON)
Europe apparently got carpet-bombed with these things. They provide
two usable serial ports; one for data and another for stuff like
signal strength, mode switches, etc. But asking it anything on the
second port makes the modem cry, grab its toys, and run home to
tell mommy what you've done."