Linked by Thom Holwerda on Tue 12th Nov 2013 23:06 UTC
PDAs, Cellphones, Wireless

I've always known this, and I'm sure most of you do too, but we never really talk about it. Every smartphone or other device with mobile communications capability (e.g. 3G or LTE) actually runs not one, but two operating systems. Aside from the operating system that we as end-users see (Android, iOS, PalmOS), it also runs a small operating system that manages everything related to radio. Since this functionality is highly timing-dependent, a real-time operating system is required.

This operating system is stored in firmware, and runs on the baseband processor. As far as I know, this baseband RTOS is always entirely proprietary. For instance, the RTOS inside Qualcomm baseband processors (in this specific case, the MSM6280) is called AMSS, built upon their own proprietary REX kernel, and is made up of 69 concurrent tasks, handling everything from USB to GPS. It runs on an ARMv5 processor.

E-mail Print r 18   · Read More · 42 Comment(s)
Permalink for comment 576756
To read all comments associated with this story, please click here.
RE: Great article
by Morgan on Wed 13th Nov 2013 01:46 UTC in reply to "Great article"
Member since:

I would think even a modern "dumbphone" would have this nastiness in it. A modem is a modem, and even the most basic cellphone has baseband software, if I'm not mistaken. So much for going off the grid by abstaining from smartphones.

And this potentially affects much more than just cellphones. My wife's iPad and Kindle are both 3G versions, which means they have AT&T-connected modems in them. The iPad modem is "turned off" via iOS, but that doesn't necessarily mean it's off altogether. The Kindle's 3G is used every few days when she doesn't have a WiFi connection.

Beyond those devices, how many cars these days come equipped with onboard cellular connectivity? Here in the US it would be most if not all GM vehicles via OnStar, as well as Teslas. I wonder if every one of those devices have the same potential vulnerabilities as your average cellphone.

Reply Parent Score: 4