The guest is David Allen Burgess, a telecom, cellphone, and cell tower expert witness.
It’s #nationaltelephoneday! Time for an exposé! Yay!
— Naomi Brockwell (@naomibrockwell) April 25, 2024
Have you ever heard of proactive SIMs? That send messages that no one wants to talk about? Yeah, I hadn't either... pic.twitter.com/KOk6NkNPch
Every once in a while a courtroom attorney is going to request cellphone activity records from Mobile operators. And then these random numbers show up in message history, and people get really confused and say, "I didn't make this," so talk me through this case that you mentioned. What did you find?
01:22. In this particular case, there was a car accident, and what we get is called an "activity record." It's produced by a mobile operator. In this case, it was AT&T under a subpoena. Right around the time of the car accident, like literally within seconds of the accident, the activity records from AT&T showed that the cell phone has sent a text message to a particularly strange-looking number. in this case, the number was 11113 4000 2. Immediately, one of the parties in the lawsuit started saying, "This is distracted driving. The driver was playing with the phone. This is why there was an accident."
02:06. So you did some testing and found out that the SIM was sending messages all on its own without the knowledge of the phone owner.
02:14. Correct. So the typical smartphone actually has 3 computers in it. It has the application processor, which is the part that most people think of as their cell phone. It's usually running Android or iOS and that's the part that people interact with. And then below that there's something called the baseband processor that manages the telecommunications functions of the phone, and it actually makes telephone calls and connects to your mobile operator for cellular data sessions. Then below that there is the SIM which is actually a full computer system it's a little hard to believe that that little piece of plastic has as much power as you would have found in a desktop computer maybe 20 years ago. It's got its own operating system. It's got its own file system. The way these are arranged is the application processor communicates with the baseband processor; the SIM communicates with the baseband processor; and the baseband processor communicates with the cellular network. This means that there can be communication going on between the baseband processor and the SIM that's not visible to the application processor. So iOS or Android don't know what the SIM in the baseband processor are doing with each other. It doesn't say that protocol.
You can think of a smartphone really from any evolutionary standpoint. In one evolutionary branch, we had cell phones which today we would call feature phones that were kind of dumb. And what's in a feature phone is a baseband processor and SIM and in a feature from the only real general-purpose programmable computer in the phone is the SIM. In the early days of cell phones before smartphones when mobile operators wanted to put special applications on a phone for things like mobile banking for example these applications would be programmed into the SIM and the SIM needed to have enough power and enough access to the base band processor to actually run those types of applications like cellular account management like I said mobile banking that's a big one and just before the iPhone age it's also very simple web browser so that one branch of evolution with the feature phones the other branch of evolution was something called pdas which were the first sort of pocket computers like a handspring visor was a big entry in this market early on what happened with the iPhone sort of the beginning of the real smartphone they took the functionality of the PDA and combined it with phone from the point of view of the Telecommunications Network what a smartphone is it's just it's still just sort of basic feature phone with this really fancy user interface on it which would be the application processor so from the point of view of a typical smartphone user they say oh it's an Android or an iOS phone and they mostly see Android and iOS and that's what the interact with from the point of view of the Telecom Network that whole Android or iOS or whatever it's just a bolt on accessory that's been attached to the phone that runs a lot of dubious third-party software that should never be trusted under any conditions that's from the point of view of the Telecom Network so from the point of view of the Telecom Network the baseband processor and the Sim are the phone and everything else is just an accessory that sits on top of those.
05:47. What you've discovered is that there are things that
