This blog post has been quite the effort—coming into it I thought I'd just learn some new things, document a simple process, and be done.
But along the way I probably spent 40 hours (and counting) trying to figure out the ins-and-outs of 4G LTE modems and Linux networking when it comes to these oddball devices.
I hope some parts of this post help anyone else new to LTE networking in Linux, and maybe somebody can help clear up some of my open questions, like:
Why doesn't Quectel have any firmware downloads on their site? (And is there any way to get them besides downloading random files posted to forums?)
Is there any advantage to using QMI (`wwan0` / qmi_wwan) vs ECM (`usb0` / cdc_ether)?
Why does it seem there's no real documentation for LTE modems on Linux? What little _good_ information I found was in random presentation slides scattered around the Internet.
Other than that it's either extremely technical documentation pages that expect a very high level of familiarity already, or some very cookie-cutter blog posts that give a walkthrough to get Internet going, but don't really explain anything.
(Also in the course of my research I learned a lot from OSMOCOM's work reverse-engineering some of the LTE modems (including the QC25 I'm using): https://osmocom.org/projects/quectel-modems/wiki/EC25 ).
But along the way I probably spent 40 hours (and counting) trying to figure out the ins-and-outs of 4G LTE modems and Linux networking when it comes to these oddball devices.
I hope some parts of this post help anyone else new to LTE networking in Linux, and maybe somebody can help clear up some of my open questions, like:
Why doesn't Quectel have any firmware downloads on their site? (And is there any way to get them besides downloading random files posted to forums?)
Is there any advantage to using QMI (`wwan0` / qmi_wwan) vs ECM (`usb0` / cdc_ether)?
Why does it seem there's no real documentation for LTE modems on Linux? What little _good_ information I found was in random presentation slides scattered around the Internet.
Other than that it's either extremely technical documentation pages that expect a very high level of familiarity already, or some very cookie-cutter blog posts that give a walkthrough to get Internet going, but don't really explain anything.
(Also in the course of my research I learned a lot from OSMOCOM's work reverse-engineering some of the LTE modems (including the QC25 I'm using): https://osmocom.org/projects/quectel-modems/wiki/EC25 ).