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Comment by marcodiego | Hacker News Reader

These modems are way powerful. This reinforces the need of open source firmware for them. They run their own OS and can stay on independent of the rest of the hardware consuming very little power. Imagine putting your computer to sleep while downloads continue and can survive geographical network migration.

A fully open source firmware for GPS/LTE modem is badly needed.

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"They run their own OS and can stay on independent of the rest of the hardware consuming very little power."

It's worse - there's a second, independent computer inside your phone that you have no control over: the SIM card.

The SIM is a standalone computer with its own processor and memory which your carrier can communicate with and upload programs to run on it without your knowledge ("OTA updates", etc.)

https://osmocom.org/projects/cellular-infrastructure/wiki/SI...

ftp://www.3gpp.org/tsg_sa/WG3_Security/TSGS3_30_Povoa/Docs/PDF/S3-030534.pdf

Do esims fix this problem? Increasingly the norm, no physical sim card at all.

https://www.hologram.io/blog/what-is-an-esim-and-how-is-it-u....

> The eSIM (embedded SIM) is a small chip soldered directly to a board inside a device

TBF, eSIM as you describe it is not "no physical sim card at all", so they might be confusing it with something else. (I assumed, based on their phrasing, that they were talking about a virtuallized SIM card running in a (hopefully suitably locked-down) VM.)

Yeah, that's nuts and frightening.

Seeing the ShadySIM project mentioned on that page reminded me of this DEFCON talk, which talks about some of the capabilities of the SIM OS (some of them run Java!) and what power they grant you over phones if you have control over the underlying cell network (legitimately or otherwise).

https://www.youtube.com/watch?v=31D94QOo2gY

I think they run Java Card, which is not quite the same thing https://en.wikipedia.org/wiki/Java_Card

And you see some of what you're talking about in closed systems too, where the system integrator can control both sides.

The Wii, and PlayStations since the PS3 have had system control processors that can perform downloads, updates, and general system maintenance on a low power processors even while the majority of the system is off. In the Wii that processor was also responsible for the majority of the network stack even when accessed from the main processor. On the PS4 that processor even ran a relatively complete FreeBSD.

Democratizing these techniques would be killer.

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