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Shopping Centers Track Customers Via Cell Phone Signals 317

oschobero writes "According an article from the Times, customers in shopping centers are having their every move tracked. Using cellphone signals, the system can tell when people enter the center, how long they stay in a particular shop, and what route each customer takes. The system works by monitoring the signals produced by mobile handsets and then locating the phone by triangulation." The particular tracking device described by the article is made by an English company called Path Intelligence.
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Shopping Centers Track Customers Via Cell Phone Signals

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  • It Does Run Linux! (Score:5, Informative)

    by fuzzyfuzzyfungus ( 1223518 ) on Sunday May 18, 2008 @04:02PM (#23455326) Journal
    Seriously, The Path Intelligence guys use, or at least got started using, the GNU Radio platform(which, incidentally, is really really cool and you ought to check out). [] [] []
    • In fact I think it was first mentioned on slashdot as an example of how cool GNURadio was. :)
      • Re: (Score:3, Insightful)

        by QX-Mat ( 460729 )
        first thing I thought... back then I thought WOW innovation, the hardware DMCA does suck.

        and I still do! it's a great piece of tech.

        If you don't want to be tracked in public, stop emitting a signal.

  • Hello John Anderton (Score:4, Interesting)

    by nacturation ( 646836 ) * <nacturation@gm[ ].com ['ail' in gap]> on Sunday May 18, 2008 @04:02PM (#23455328) Journal
    Now all we need is retinal/facial recognition and we'll have the perfectly offensive onslaught of advertisements available to us.

    How did you like the last ad greeting you by name, John Anderton?
    • Re: (Score:3, Insightful)

      by Z00L00K ( 682162 )
      Just consider that this is a possible privacy violation.

      What can be worse is if the cash register matches your phone with your purchase and re-uses that next time you approaches the shop which can make them to play an ad on a screen "Special Offer to Mr. Jones; 10-pack of Strawberry taste condoms" when you approach that store with a wife/girlfriend allergic to latex.

  • Aren't there laws on the books with serious penalties for unauthorized reception of private radio signals? Why shouldn't the mall owners be busted for this snooping just like they would if they were hacking DirecTV signals?
    • by spazdor ( 902907 )
      There might be a legal distinction between decoding enough data to snoop on a call, and simply decoding enough data to distinguish one unique signal source from another.

    • yes there are (Score:5, Informative)

      by Anonymous Coward on Sunday May 18, 2008 @04:13PM (#23455410)

      Under Section 5(1)(b) of the WT Act 1949 it is an offence if a person "otherwise than under the authority of a designated person, either:(i) uses any wireless telegraphy apparatus with intent to obtain information as to the contents, sender or addressee of any message whether sent by means of wireless telegraphy or not, of which neither the person using the apparatus nor a person on whose behalf he is acting is an intended recipient;

      This means that it is illegal to listen to anything other than general reception transmissions unless you are either a licensed user of the frequencies in question or have been specifically authorized to do so by a designated person. A designated person means:

                              the Secretary of State;

                              the Commissioners of Customs and Excise; or

                              any other person designated for the purpose by regulations made by the Secretary of State.


      (ii) except in the course of legal proceedings or for the purpose of any report thereof, discloses any information as to the contents, sender or addressee of any such message, being information which would not have come to his knowledge but for the use of wireless telegraphy apparatus by him or by another person."

        This means that it is also illegal to tell a third party what you have heard.

      With certain exceptions, it is an offence under Section 1 of the Regulation of Investigatory Powers Act 2000 for a person - "intentionally and without lawful authority to intercept, at any place in the United Kingdom, any communication in the course of its transmission by means of:

                              a public postal service; or
                              a public telecommunication system."

      It is similarly an offence to intercept any communication in the course of its transmission by means of a private telecommunication system.

      According to Ofcom, scanners and monitoring radios can be legally sold, bought and used in the United Kingdom, without the need to obtain a license, provided they only receive radio services meant for general reception by the public. In the UK such services include Citizens' Band, Amateur, licensed broadcast radio, weather and navigation broadcasts.

      It is only illegal to use scanners to listen to licensed private services such as the police and taxi radio transmissions and other prohibited or private broadcasts not intended for the public. Listening in on such broadcasts is an offence under Section 5(1) (b) of the Wireless Telegraphy Act 1949.

      In order to help the public understand what it can and cannot listen to, Ofcom publishes a Radio Authority information sheet titled RA-169.

      Anyone who intends to listen to radio transmissions should be aware of the following, it warns: A license is not required for a radio receiver as long as it is not capable of transmission according to The Wireless Telegraphy Apparatus (Receivers) (Exemption) Regulations 1989 (SI 1989 No 123). An exception to this is that it is an offense to listen to unlicensed broadcasters (pirate broadcasts) without a license and licenses are not issued for that purpose.

      Although it is not illegal to sell, buy or own a scanning or other receiver in the UK, it must only be used to listen to transmissions meant for general reception - Amateur and Citizens' Band transmissions, licensed broadcast radio and weather and navigation broadcasts. It is an offence to use your scanner to listen to any other radio services unless you are authorized by a designated person to do so.

      So possession of the equipment is allowed so long as it is not used to listen to prohibited communications in the UK. []
      • But this isn't listening to the contents of any communications ie the phone calls or text messages. It is just picking up the signal the phone sends to the base station to say where it is.
        • You are receiving a broadcast you have not been authorised to listen in on. Specifically, if they actually inspect the packets and determine the IMEI number (assuming it's not encrypted these days) then you're DEFINITELY breaking the WTA(R) Act and these guys will be in serious trouble unless they've obtained an exemption or explicit authority from the mobile networks.

          Not only that, but if they store the IMEI numbers, I'm fairly sure they wouldn't be able to sell that data, under the Data Protection Act.

          I d
      • Re: (Score:3, Informative)

        by SoopahMan ( 706062 )
        I'm not a lawyer and I suspect you aren't either, but the important part of the law here is this:

        "intent to obtain information as to the contents, sender or addressee of any message"

        If all they're doing is watching cellphones walk by and notice that there's a signal moving along this vector, triggering antennae bit by bit as they pass, and another moving along another vector, then they're certainly steering clear of this law.

        But if they're reading the contents of the signal, they're probably violating it. H
    • by mikael ( 484 ) on Sunday May 18, 2008 @04:54PM (#23455706)
      They intercept the IMEI number of the cell phone; the serial number of the hardware, not your personal telephone number. You could change the telephone number simply by unlocking the phone and inserting a new SIM card. But the IMEI never changes unless you got a new phone.

      Like cable broadband networks, the actual data transferred for calls is encrypted, but the IMEI is not.

    • No. I believe they only cover unauthorised transmission of radio signals, and unauthorised phone tapping, which this doesn't do.
  • by brenddie ( 897982 ) on Sunday May 18, 2008 @04:06PM (#23455352)
    If the mall is going to use my equipment for their benefit, I should be warned before entering the premises. I see no mention on TFA about the mall warning its customers about the tracking system , besides looking for the antennas on the walls but those can easily be concealed. Maybe someone can come up with a device that changes IMEIs on the fly creating one man stampedes/mobs
    • by Irish_Samurai ( 224931 ) on Sunday May 18, 2008 @04:19PM (#23455442)
      They aren't using your hardware, they are observing the public signal that your hardware is sending to the towers outside the mall.
    • Re: (Score:3, Informative)

      by Yocto Yotta ( 840665 )
      IMEIs are serial numbers that the networks use to make sure your calls go to your phone . . . unless you want to carry around a useless radio emitting brick for absolutely no reason BUT to fuck with the company, changing IMEIs would be a bad idea. There's a lot of work that's gone into preventing that from happening, the fraud possibilities would be endless if the serial number of a handset could be easily changed. I'm not saying the can't be changed, there's a huge grey market around that very practice, b
    • Generally speaking, when you broadcast electromagnetic waves you lose any ownership or privacy interest in their existence (note that the content of the message is distinct from the existence of the message). So while the equipment might be yours, the radiation is public and you have no right whatsoever to dictate what happens to them.

      You don't want to be tracked by your cell phone, turn it off.
      • on the surface it's sounds right...
        but what if you drop coils under high-power transmission lines to garner free electricity?

        what if you tune in on HBO or skinamax without a subscription?

        what if you slurp a optical link between two banks using an IR bridge?

        how about reading vibrations off a window with a laser to listen in on a conversation? or with a shotgun microphone

        what if I'm standing across 86th ave in NYC in my apartment, looking into your bedroom making love to the wife, or the family dog?

        these are
        • Well, IAAL so I'm going to take a stab at it here:

          but what if you drop coils under high-power transmission lines to garner free electricity?

          Let's suppose that there were power-company high-voltage lines over your property (usually they buy the strip of property right underneath). In that case, putting coils underneath would disrupt their service (by draining power) which is a crime (tampering with or disrupting an interstate power delivery system).

          what if you tune in on HBO or skinamax without a subscription?

          HBO and Cinimax are encrypted. Breaking their encryption is not different than me breaking your phone encryptions

          what if you slurp a optical link between two banks using an IR bridge?

          This is a good one, since the i

    • If you don't want to be tracked, then don't broadcast a signal. You're basically doing the electronic equivalent of yelling "I'M IN THE PRODUCE DEPARTMENT" as loud as you can.
    • You're wearing a radio beacon on your belt, and now you're offended somebody's paying attention to it?
  • So vague... (Score:5, Funny)

    by oskard ( 715652 ) on Sunday May 18, 2008 @04:08PM (#23455370)

    customers in shopping centers are having their every move tracked.

    Which customers? Which shopping centers? ALL OF THEM? Am I being tracked?

    Put on your tin-foil hats everyone!
  • by religious freak ( 1005821 ) on Sunday May 18, 2008 @04:10PM (#23455384)
    Whenever I read big-brother type stuff like this, I'm reminded of one of the best lectures I received regarding the direction of IT (and this was years ago)

    In speaking about GIS he outlined some items that seemed very spooky and seemingly improbable things that would happen - then he discussed the results of those things occurring as if they were a given. I was skeptical that they'd even happen, but they are beginning to... stuff like this article mentions, how it will be very close to impossible to travel without a cell phone, and how that would essentially mark you (not in the crazy 666 sense) for all kinds of crap people want to sell to you.

    At the end, his point was that these types of things will be reviled in name only, but once people receive the benefits of the technology, they'll love it. We're headed down this path whether we like it or not; privacy will become a very relative thing in the next couple decades. We will need to rely exclusively on the good faith of the companies that guard our information.
    • Re: (Score:2, Interesting)

      by dnwq ( 910646 )
      I'm inclined to agree - companies don't want to advertise to people who don't want to buy their stuff, it's a waste of effort and makes people hate them.

      If data mining progresses enough, pretty soon advertisements will only appear to those people receptive to such advertisements. So people will find advertising in general a good thing... good enough to be worth trading away your privacy? Probably not for most Slashdotters, but probably so for the average mall rat.
      • I don't agree. A whole lot of advertising is about generating demand -- not finding it, but generating it. The goal is to convince people that they must buy stuff they've never even considered buying before. That attitude will assure that annoying advertising will always be with us.

        I expect that 'targeted' advertising will become just another version of 'the suckers list' - that's the list a boiler-room (aka scam) company keeps of the suckers who fell for their last scam because chances are if you could
      • great just what I want more advertising on shite I don't want or need. So what if I go to boat US and spend $200 I don't need your flyer as that $200 worth of gear covers everything i need for the next 2 years. your advertising dollar is now wasted.

        Or big deal I go into payless and buy shoes. I don't need the catalog on womens shoes as I am a guy. don't send it to me, it won't help you sell more shoes as i have more than i want as it is(specialty footwear for special applications).

        targeting advertising
  • How does this work? (Score:3, Informative)

    by imrtt ( 1287370 ) on Sunday May 18, 2008 @04:12PM (#23455402)
    This is pretty cool. The website claims accuracy of 1-2 meters. If they indeed use triangulation, their equipment has to be able to measure time down to ~1/300 millionth of a second. BTW, chances are that tracking is anonymous. I don't believe phones transmit phone numbers or other private information unencrypted.

    Since this article is about cell phone tracking, I thought I would mention a free GPS tracking service that we recently launched. It's called InstaMapper. There is a DIY that explains how to track a car in real-time using a $40 prepaid cell phone: []
    • I believe the IMSI gets transmitted in the clear, but rarely (most of the time the TMSI is sent, and that changes randomly).

      It's not that anonymous if you can get an IMSI - that's unique to your account and never changes... TMSI is random enough to be pretty useless for any medium term tracking.
  • What about the shopping centers with a poor signal there some places where you get a weak signal some times parts of a store get no signal at all.
    • They will track you the best, because when the signal quality gets worse, your phone increases its own signal strength in order to keep the connection as long as possible.
    • Those actually make the system's life easier. In modern phones, the phone adjusts the power of its transmissions in order to conserve energy. If contact with the tower is good, it will use less energy, if conditions are bad, it will use more in an attempt to compensate.
      Since this tracking system listens to your phone's transmissions, it should actually have an easier time in areas where tower transmissions are weak and phone transmissions are strong.
      • Since this tracking system listens to your phone's transmissions, it should actually have an easier time in areas where tower transmissions are weak and phone transmissions are strong. ..which is an easy thing to simulate with a sufficient amount of radio reflective material in the walls of the store.
  • by timothy ( 36799 ) on Sunday May 18, 2008 @04:22PM (#23455472) Journal
    Lots of fun things you can imagine doing with this :)

    Gather as many cellphones as possible (from cooperating friends etc). Put them all in a small basket.

    Have them visit for a while in ... the dressing room at Victoria's Secret / Stall 3 in the bathroom at Baskin Robbins / the service elevator in any place you can find with a service elevator.

    Or just have people do a lot of trading, so person A keeps visiting place 3, over and over and over. (Also works with grocery loyalty oath cards.)

    Have a massive "appearance" / "disappearance" fest. Hey! 50 people just appeared inside Best Buy! No ... no, wait, they didn't. Errr ... 50 people just appeared spaced in a grid around the parking lot! No, they've disappeared.

    • That kind of stuff would be easy to verify in the security cameras - plus any data gathering system will reject out of band data like that (there will always be a few people who don't act like the rest.. their data isn't meaningful in general).

      Going into service elevators/hiding in dressing rooms/repeatedly visiting the same place and not buying is going to attract the attention of security too. Being caught with a bag with 50 mobile phones in it is gonna take some explaining - you may be innocent.. you ma
  • Other things these systems could do include correlating phone IDs with missing big-ticket merchandise to identify possible shoplifters, or look for suspicious activity like repeated visits to rest rooms or other semi-private places by the same set of IDs. Combine it with video records and credit card records and you can get a fair amount of visitor identification without going to the phone company for tracing. Not enough to act, but enough to be useful to security personnel.

    It's another step towards Brin's transparent society.
    • by Anonymous Coward
      > look for suspicious activity like repeated visits to rest rooms

      Either you're a terrorist or you've got the runs, and we're not taking chances!
      • I was talking about frequent visits by the same groups of people.

        Now that's still possibly a parent and a child with the runs rather than a drug deal, but you're right, there's a huge potential for false positives from any system like this, but do you really think that will stop them?

        That's kind of the point.
  • by wfstanle ( 1188751 ) on Sunday May 18, 2008 @04:24PM (#23455486)
    I don't have objections to it being done correctly. By correctly I would want the following issues to be addressed. 1. No attempts to find out who the cell phone belongs to. (No personally identifiable information). 2. The id number that the cell phone transmits is never stored in any way. The use of an internal identifying number would be acceptable as long as no link was made between the actual cell phone identification number and the internal id number is stored. 3. Every time you visit the mall you get a new internal id number. This would prevent getting information about repeat visits to the mall. My concerns about storing personally identifiable information stems from the government. The government would subpoena for the mall owners cell phone information and all sorts of fun would begin. Even if only a cell phone id number is stored it would be enough for the government to use as a starting point.
    • I think 1. is assumed - the cell phone companies wouldn't give that information, except to law enforcement. 2. and 3.? That's the valuable stuff - why do you thing they spend so much pushing store cards? They'll be the exact reason they're even trying this.. If they get your IMSI you're hosed unless you always use payT phones and throw them away after visting the store. Luckily IMSI is only transmitted when the phone first connects to the tower (of course a small 'no signal' area you pass through on ent
      • But do they need cell phone companies to give them that information?

        If it is accurate to 2 meters, they can figure out when you are at the till, and they can get your credit card / loyalty card details from the till to match the phone to you.
  • by wherrera ( 235520 ) on Sunday May 18, 2008 @04:33PM (#23455552) Journal
    Okay, fine, so now I want to use SMS to send my shopping list to the mall, and get in return directions to the aisle and row of the widget I want, with the price displayed on the map on my phone of the mall, with directions if I ask, so I can decide which of two competing stores to go to. Better still, I would not mind if the the higher priced store might offer me a deal when they see me entering their competitor's shop. And no colluding on price, please, I will go to another mall...

  • by Anonymous Coward on Sunday May 18, 2008 @04:39PM (#23455608)
    Iam sure the cellphone companies will love to put a stop to a third party using their $billion privately licensed network infrastructure for commercial gain that they are not a part of.
    Of course if ALL the cellphone companies have giving their blessings to recieve their frequencies then the legal threat is reduced, somehow from reading about their tech they dont have permssion.

    i presume they have lawyers?, even a ham radio operator could tell you the laws on reception of signals, bottom line no permission, no reception or usage in any way at ALL
  • Unless they inform me (signs posted prominently on the doors or walls, for example), then I consider this to be gross invasion of privacy.

    And of course, if they were to post such signs, then I would go to another shopping center!

    Which is NOT an excuse for them to keep using it without telling people. What I am getting at is, I object to the practice and I believe most others do too.
  • A simple search on Google will bring any number of articles on the decline of the American mall {even though TFA discusses UK malls}. The article(s) specifically state the financially affluent are abandoning the malls. Despite what the articles may summarize, the reason I don't shop in malls is simple -- mall stores carry nothing I need. I park outside the single store I need to visit, get the items I require, and leave.

    I am quite confident any tracking will show an inverse relationship between time spent
  • Yes, your cell phone does indeed transmit an identification signal - one that can be positively identified. That's fundamental to the way cell phone networks work - and the cell phone providers can easily link the cell phone's ID to your account details. Various law enforcement agencies have been making use of this for many years already.

    What's changed is that now the technology is available for corporations to access your cell phone's broadcasts and use that to determine your movements. It's pretty certai

  • It wouldn't surprise me a bit if the phones, as phones (but not as people) could be tracked by the radio signals they send out constantly. It could lead to interesting movement information for the stores and the mall management.

    But can the tracking infrastructure on its own (ie, without cooperation from the cell phone companies) determine who is the owner of a given phone as it moves through the mall? Its one thing to say "phone ABC123 was in the gap for 20 minutes, and then went to cinnabon", but a ver
  • Article, though datelined "San Francisco", seems to refer to tracking being done in a GSM-only environment. They talk about looking at the IMEI of the handsets, which is a GSM term, and the locations mentioned seem to be in the UK.

    In the US, they'd have to be decoding three to six different protocols on at least three frequency bands. Those nodes would cost a fortune. You'd have want that location information pretty badly to fund something like that. Not to mention multipath issues.

    I know it would work i
  • Pure BS! (Score:2, Interesting)

    by cuby ( 832037 )
    The type of thing they claim, not even network operators can do, and they assign all the frequencies in use, so, they know who is who. Cell phones (GSM, at least) don't broadcast unless there's something to do, like make a call, change base station, etc. How they will monitor something that is not broadcasting?

    This can only be achieved using monitoring software IN the cell phone, using network monitoring (a big subject).

    I don't know what they are monitoring, but for sure, it is not GSM phones.
    • Re: (Score:3, Informative)

      by robo_mojo ( 997193 )
      As a fun experiment, try placing your cellphone (turned on) next to an audio receiver, or television, or any other device that is susceptible to radio interference.

      What you'll soon see is that the phone is causing interference (through transmissions) intermittently. For example, every few minutes you will hear slight buzzing from the speakers of your radio or television (and if it is a television you might see the picture go wavy, too).

      This is a well-known phenomenon, so saying that phones do not broa
  • All of this technology has only 2 practical uses: law enforcement, specifically amber alerts, and spam.
  • Pay me!!! (Score:3, Insightful)

    by wikinerd ( 809585 ) on Sunday May 18, 2008 @06:59PM (#23456544) Journal
    Everyone thinks of this story in terms of privacy but no one thinks of it in financial terms: My shop usage data have great financial value (otherwise the shops wouldn't pay to install surveillance systems) and the shop's surveillance is involuntary - I am not given a choice whether to allow them track me or not, except if I avoid transmitting wireless signals while near their shop. As the data collection is not voluntary and my shop usage data have financial value, I demand payment from shops using this system. I want a share of my shop usage data's financial value.

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