Re: Unwarranted Search
It ought to be fairly straightforward for the FBI to claim that the details of how the tool works are classified
The tool is a femtocell and a PC which simulates the home network. All femtocell vendors have been shipping such toolkits to law enforcement since before the femtocell as such came to be (in the days when it was just a base-station over IP). I worked in this area and our first paid orders where not from SPs - they were from law enforcement and "you do not need to know this customer" 2-3 years before the first basestation over IP (not even a femtocell yet) trials.
The secret "sauce" is how exactly does it simulate (if at all) the phone network. In order to do it successfully you need have the correct encryption keys for the correct mobile. While in theory it is possible to allow/reject mobiles based on IMSI that does not work very well, so the real secret of Stingray is not the cell part of the technology, it is the "talk to the home network" portion. In order to be as idiot friendly and as prevalent in law enforcement use, it has to be talking back to the mother ship(s). It has to cooperate actively with the home networks including radio management. Otherwise, its deployment will show up as disruption in mobile and people sooner or later will notice.
This is the interesting bit and it will have to be disclosed in court, because it will be a part of the proof that the suspect phone was indeed traced (encryption keys).
Biting the hand that feeds IT
