Bluetooth Surveillance

7/30/2019 Bluetooth Surveillance

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How Bluetooth

Surveillance Works

Inside this Article

1. How Bluetooth Surveillance Works2. Bluetooth Discoverability3. Bluetooth Positioning and Tracking

How Bluetooth Surveillance Works

If you were to randomly pick up a piece of electronics equipment in yourhouse, there's a reasonable chance that it has Bluetooth capabilities,especially if the gadget in question is fairly new. Whether it's a cell phone,smartphone, laptop, printer or keyboard, Bluetooth wireless technology hasmade life easier for those of us with too many electronics on our hands.Bluetooth devices get rid of frustrating wires and expensive adapters byusing short-range radio signals to connect devices to each other and sendinformation back and forth.

If you own a Bluetooth device, can someone trace your activity

Bluetooth is especially common in mobile phones, which make up more

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than 60 percent of the Bluetooth market . Bluetooth headsets, for example,transmit calls from your phone to the headset in your ear -- this allows youto keep your phone in your pocket, backpack or handbag while walking

around. It's also helpful to drivers wanting to cruise around hands-free .

Imagine, though, talking a walk through a crowded area -- perhaps theshopping district of a big city. Maybe you're just doing some casualwindow shopping, and you've kept your phone with you and left Bluetoothon "discoverable" mode. This allows other Bluetooth phones to locate you.As you linger in front of a shoe store and consider a new pair, your phone

beeps: Someone's sent you a text message. It reads: "We know where youare. Having fun shopping?" Sounds like something out of a movie, right?

Such a thing is possible, and it's happened before. In fact, it's the verynature of Bluetooth -- a technology that can search for and locate otherdevices that also have Bluetooth -- which has some people concerned.Security has long been an issue with this technology -- bluejacking, forinstance, although simply a harmless prank, allows Bluetooth users to send

out unsolicited messages to nearby devices. Because Bluetooth devices areto some degree traceable, the concept ofBluetooth surveillance has beenintroduced into the tech world.

The phrase Bluetooth surveillance might conjure up images of Big Brotherin George Orwell's dystopian novel of the future, "1984," but is that reallythe idea? How does Bluetooth surveillance work, and who would use it?Can it be used for good or for evil? To learn about Bluetooth surveillanceand whether or not you should remain discoverable, read on.

Bluetooth Discoverability

Before we dive into Bluetooth surveillance, we'llwant to take a look at how Bluetooth itself works and understand whatmakes the technology traceable. Bluetooth devices use the free, 2.4-gigahertz radio band known as ISM, which stands for industrial, scientificand medical devices. The band is unlicensed for low-power use, so headsetsand other Bluetooth accessories use very little in the way of batteries. Whileany two Bluetooth devices can share data at a range between 10 and 100meters (33 and 328 feet), phones usually operate at the former, laptops at

the latter. Any Bluetooth device can communicate with up to seven otherdevices at a time.




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After you turn any Bluetooth-capable device on, the most basic securityfeature on it is the ability to go into one of two modes: "discoverable" or

"non-discoverable." This information is typically found in the "settings"option of a device's control panel, where you can select whether or not your

phone or laptop is visible to others within the area.

If several Bluetooth devices are set on discoverable mode, they all have theability to search for and locate each other, so long as they remain withinrange. Every device has its own address, a unique 48-bit identifier with six

bytes of information that might look like this: 01:23:45:67:89.10. The firstthree bytes (01:23:45) are assigned to the specific manufacturer of the

device, while the last three bytes (67:89:10) are assigned by themanufacturer. These make each device entirely unique.

So how could someone track your movement if you left your phone ondiscoverable? Would they have to follow you around all day long, or isthere a simpler way? To learn how a Bluetooth surveillance network is setup, read the next page.

Since many terms related to Bluetooth surveillance use some variation of

the Bluetooth brand name, it helps to get a few sorted out.

Keeping a Bluetooth

device in"discoverable" mode

allows other gadgetswith Bluetooth to

locate it within acertain range.




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Bluejacking, a prank that involves sending fellow Bluetooth usersunsolicited text messages, doesn't actually have anything to do withhijacking, even though the name implies it. The term is simply a hybrid of

Bluetooth and "ajack," the username of the Malaysian IT who discoveredthe glitch and spread the news over the Internet.

Bluejacking, although potentially irritating to users who don't want anypart of the joke, won't harm or steal anyone's information. Bluesnarfing, onthe other hand, happens when an attacker reads, changes or copiesinformation from a person's phone, such as a phone book, address book orcalendar. More serious infringements of bluesnarfing include taking oversomeone's phone and using it to make phone calls, send text messages orsurf the Web.

Bluetooth Positioning and Tracking

Locating several Bluetooth users with a typical mobile phone is relativelysimple: You just turn on your phone and search for every discoverabledevice. But you could only monitor the people moving in and out of yourBluetooth's range, which is most likely a 10-meter (33-foot) circle aroundyou. If you wanted to track a specific address, you'd have to visually locatethat person's physical device and follow it around all day, which wouldeasily blow your cover.

Setting up a network of Bluetooth receivers that record the locatioBluetooth surveillance possible. Could shopping mall stores do this




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Creating a Bluetooth surveillance network solves this problem. If several

Bluetooth-enabled receivers are strategically placed to cover a large area,they can track the positions of any discoverable device, recording andsending any data back to a single address. Each Bluetooth receiver acts like

any regular Bluetooth device: It searches for every device within range. If aperson walked down a 100-meter-long (328-foot-long) street and eachBluetooth receiver had a range of 10 meters, five receivers with a radius of20 meters (66 feet) would be needed to track that person's movement. As hewalked toward the street, the first receiver would track him for the length ofthe first 20 meters, the second for the next 20 meters, and so on for thelength of the street.

So how have people used this system to track people? One of the earliestuses of Bluetooth positioning and tracking technology is the Aalborg Zoo,the largest zoological garden in Denmark. The point of installing the systemwas not to put the zoo's patrons under surveillance or to see whichexhibitions people went to more often. Instead, special "Bluetags" were

made available to prevent parents from losing valuable belongings that tendto wander off -- their children. A parent could attach a "Bluetag" onto achild, and Bluetooth receivers around the zoo would track the child'smovement.

Some people worry about others using this sort of technology illegally andmaliciously. A shopping mall, for example, could install a Bluetoothsurveillance system throughout its entire area to monitor the movements ofBluetooth owners. Although it wouldn't present a perfectly accuratedescription of a person's movement, the system could create a general mapof his path and even compare how long someone stays in a certain area.With this knowledge, store owners could analyze shopper's behavior andchange advertisement positions accordingly without anyone ever knowing.

It's difficult for someone to use Bluetooth to identify you in particular,unless you've chosen to include your name or some other personallyidentifiable information in the name of your phone, smart phone or PDA.Still, if you're concerned that someone might be able to track you down viaBluetooth, the best defense is to make your device non-discoverable to

others when not using it.




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Bluetooth Surveillance