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Thursday, September 22, 2011

Harris: Helping Big Brother Track Your Cellphone

Intrigued by this report at the WSJ describing a system call "StringRay" for tracking cellphones I did some research.  (This required some work because apparently Harris is not too interested in people like you and me knowing what they do, how they do it, where they are, etc.)

The "StringRay", as well as related products "KingFish" and "StringRay II" are cellphone tracking devices used by local, state and federal governments in the US to track cellphones without need of a warrant.

Unlike the typical "get a warrant, get carrier data" tracking typically used these devices work in a unique and questionable way:

All cellphones maintain communication with cellphone towers by periodically sending small bits of data back and forth with the towers.  As the cellphone moves from place to place it goes in and out of range of various towers.  When a tower and cellphone are first "introduced", i.e., the phone appears for the first time in the towers range, the phone and tower "shake hands" so that the tower is aware of the phones presence.

Once the tower knows where the phone is the cellphone system knows where to route the call.

Now things are actually a little more complex than this because tower ranges overlap, there is interference, etc. but the basic idea is that tower knows where the cellphones its talking to are in a general sense, i.e., inside some radius around the tower.  If multiple towers are aware of the phone then, by using the relative strength of the signal at each tower one can triangulate to where the phone might be.  (This is typically what's acquired by law enforcement.)

The StingRay devices, on the other hand, allow law enforcement to "act" as if they themselves were a cellphone tower and asking all the cellphones in the area to register with it.  So if some crook has his cellphone "on" - even though he's not talking - the faux tower run by the cops knows about his cellphone.  By coupling this with directional antenna technology you can easily track someone.

These devices are portable, they run on 12V DC, and have associated antennas that can be used to get a "fix" on your location by measuring signal strength to your phone.  (Your phone has a unique ID that all the towers know outside your phone number - I am not sure how the StingRay is able to track you but there is some way to associate your phone and number.)

Since law enforcement is its own cell tower there's no need to get a court order to run the StingRay, i.e., they don't have to ask AT&T for information about you.  They simply collect it directly from your phone.

(Its hard to imagine how local governments circumvent FCC regulations for this but...)

This device is made by the Harris Corporation and sold exclusively to governments of all sorts in the US (see this sole source award for the US and this for the City of Miami).  There's also a handy GSA number

for the Harris contract which means that any federal agency can buy one.

So, from the City of Miami PDF, we see that this system costs $51K USD.  That includes everything you need for warrantless tracking of cellphones (directional antenna arrays, pc adapters, a 12V interface for powering the device from your car, etc.)  There's even spec sheets and contact information for the salesman.

As you can also see from the link for Miami Harris operates out of a P.O. Box for this type of equipment.

I wonder why?

(Harris used to sell something called a "Datacraft Computer" which, fortunately, history has mostly forgotten.  Google cannot even find a picture of one.)

So tracking you, listening in on your calls, all of that, is only $51K USD away - a small sum for any city with big drug or crime problems.  I imagine that anyone with money and the right "connections" who could actually find these Harris folks might be able to buy one of these.  After all, it is only money...)

Not everyone, however, is enthusiastic about this technology, for example the Electronic Freedom Foundation published this about these devices.

Personally I don't see how some detective in Miami Florida clears the FCC for operating this type of device - at least I would presume that there is a reason real cellphone companies like AT&T and Verizon spend millions or billions to buy the same bandwidth...

(BTW, the StingRay covers both CDMA (Verizon-type) and GSM (ATT&T) phones on all bands - so no one is safe.)

I also wonder if my cellphone, if within the reach of the StingRay, is being tracked as well - even if law enforcement is not interest in me per se - because my phone would register as well...?

I would think this violates my 4th Amendment rights... which are "The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized."

One imagines that these guys sit around in unmarked cars eavesdropping on whatever they can pickup waiting for the "criminal" to "make a move..." - after all there are probably hundreds or thousands of phones active in any given urban towers range.

Of course, if you're really that concerned about things just turn your cellphone OFF and/or take out the battery.

You could also run Skype.

Hell, you could also write you own secure VOIP application (but they could still track your location).

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