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Feds Can Locate Cell Phones Without Telcos 199

schwit1 sends along an Ars Technica report covering the release of documents obtained under the FOIA suggesting that the Justice Department may have been evading privacy laws in their use of "triggerfish" technology. Triggerfish are cell-tower spoofing devices that induce cell phones to give up their location and other identifying information, without recourse to any cell carrier. "Courts in recent years have been raising the evidentiary bar law enforcement agents must meet in order to obtain historical cell phone records that reveal information about a target's location. But documents obtained by civil liberties groups under a Freedom of Information Act request suggest that 'triggerfish' technology can be used to pinpoint cell phones without involving cell phone providers at all. The Justice Department's electronic surveillance manual explicitly suggests that triggerfish may be used to avoid restrictions in statutes like CALEA that bar the use of pen register or trap-and-trace devices..." The article does mention that the Patriot Act contains language that should require a court order to deploy triggerfish, whereas prior to 2001 "the statutory language governing pen register or trap-and-trace orders did not appear to cover location tracking technology."
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Feds Can Locate Cell Phones Without Telcos

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  • Re:batteries ftw (Score:2, Informative)

    by Zymergy ( 803632 ) * on Monday November 17, 2008 @07:46PM (#25794527)
    Removing batteries only protects from the active 'pinging' replies.

    The potato-chip bag only works if the mylar plastic's aluminum layer is sufficiently thick to act as an effective Farady Cage. http://en.wikipedia.org/wiki/Faraday_cage [wikipedia.org]
    Just as RFID tags do not require batteries to give disclose their location and unique identifiers, modern cell phones also have similar functionality batteries or not...
  • Re:batteries ftw (Score:4, Informative)

    by Anpheus ( 908711 ) on Monday November 17, 2008 @07:52PM (#25794619)

    No, most cell phones have one and only one battery.

    And for low power EMF (cell phones) even very thin cages can be used, I wouldn't be surprised if most aluminum foil were more than sufficient.

  • Re:batteries ftw (Score:5, Informative)

    by zippthorne ( 748122 ) on Monday November 17, 2008 @07:53PM (#25794641) Journal

    For your Faraday cage to be effective, it has to be very conductive. The higher the resistance, the worse it works.

    A thin layer of metallised Mylar is not going to attenuate the signal very much. Certainly not enough to prevent my receiving a call just now. I even tried sealing the end with aluminium tape (which, btw, is much better than duct tape for almost everything, especially ducts).

    If you want to make sure some piece of electronics isn't transmitting/in a position to be heard, there are only a few tools that are up to the task. If you're in a hurry: hammer. If you want to be sure: nuke from orbit.

  • by bhtooefr ( 649901 ) <bhtooefr@bhtooefr. o r g> on Monday November 17, 2008 @08:01PM (#25794757) Homepage Journal

    The thing is, you don't have control over the GSM/CDMA radio - it's controlled by a completely separate processor, and get access to the microphone, speakers, and a serial link to the main processor, so that the processor powering the phone's OS doesn't cause spurious radio transmissions.

    Some data goes back and forth, yes, but you probably won't be able to tell when it's doing this versus a legit cell tower connection...

  • by Anonymous Coward on Monday November 17, 2008 @08:18PM (#25794977)

    Barack will not change America in the way you're hoping.

  • Re:batteries ftw (Score:3, Informative)

    by Facegarden ( 967477 ) on Monday November 17, 2008 @08:25PM (#25795083)

    Just as RFID tags do not require batteries to give disclose their location and unique identifiers, modern cell phones also have similar functionality batteries or not...

    Umm... no they don't? That's BS.
    -Taylor

  • Re:batteries ftw (Score:5, Informative)

    by Fastolfe ( 1470 ) on Monday November 17, 2008 @08:26PM (#25795097)

    Just as RFID tags do not require batteries to give disclose their location and unique identifiers, modern cell phones also have similar functionality batteries or not...

    Do elaborate, please. RFID does, in fact, require power. It's just that that power is provided by the reader when in proximity to the tag. Are you suggesting there are RFID tags embedded into "modern cell phones"? Or something else? If you're suggesting that cell towers have the ability to blanket a region with an electric field capable of getting all of the cell phones to respond (loudly enough) to a "ping" for their location, I'm afraid I'm going to have to call BS. So what is this "functionality" that you claim allows cell phones to be identified and located without a battery?

  • Re:batteries ftw (Score:5, Informative)

    by IorDMUX ( 870522 ) <mark DOT zimmerman3 AT gmail DOT com> on Monday November 17, 2008 @08:41PM (#25795283) Homepage

    Just as RFID tags do not require batteries to give disclose their location and unique identifiers, modern cell phones also have similar functionality batteries or not...

    I am a cell phone designer, and a phone reporting *anything*, even just a handshake, to a tower thousands of meters away takes significant power.

    It is possible that the little coin cell battery in most phones could handle the receiving of a signal, and then wake the phone up and have it reply with the main battery, (though to the best of my knowledge we don't let phones do that [and yes, I design power systems]), but if the main battery isn't there, that's a no-go.

    Passive RFID is a completely different batch of apples than active cellular communications. Passive RFID has a maximum range of around 10 meters (phased array antennas notwithstanding, but seriously...). You would need a specially designed phone to use some sort of active RFID when the battery is removed, and we don't make those.

    Now, this isn't to say that I'm not pissed at the Feds for doing something like this--perhaps even more so than the average user. I can see how they are taking advantage of perfectly innocuous and functional code and systems designed by my co-workers to agreed standards, and then using those standards to make our customers lose their privacy.

    *sheesh*

  • Re:batteries ftw (Score:3, Informative)

    by phantomfive ( 622387 ) on Monday November 17, 2008 @10:37PM (#25796549) Journal
    It's not. Even multiple layers of aluminum foil will not block a cell phone signal. The best thing is to get a cell phone jammer, but those are often not readily available. Second is a faraday cage, but those are expensive and not really convenient. Third are EMF bags, which look like static shielding bags, but work slightly better, but realistically those don't work very well either.
  • by citizenr ( 871508 ) on Monday November 17, 2008 @11:11PM (#25796787) Homepage
    Something tells me they dont sell it in corner shops :) more like "agencies only" equipment just like Cell jammers in Poland.
    But no need for that, we are talking about localisation, not intercepting calls http://yro.slashdot.org/article.pl?sid=08/05/18/1838222&from=rss [slashdot.org]
    http://www.pathintelligence.com/website-prodnserv.htm [pathintelligence.com]
    you can buy boxes from that company and build your own Triggerfish system (using cab fleet for example to cover whole city)
  • Re:batteries ftw (Score:3, Informative)

    by penguinchris ( 1020961 ) <.moc.liamg. .ta. .sirhcniugnep.> on Tuesday November 18, 2008 @03:27AM (#25798643) Homepage

    Just so you know, here in Southern California, where the FasTrak system the parent mentions is, most toll roads that I'm aware of do not take cash. You must have the FasTrak, or presumably they will photograph your license plate and you will pay a hefty fine.

    Here it's different than most places, of course; there are usually alternate routes you can take just as easily that don't have a toll. It'll just take you a little longer; the main difference being that the free route will have our notoriously heavy traffic or be jammed all the time, while the toll road you'll presumably fly through.

    They dynamically adjust the toll depending on traffic level, to make sure the toll road is always operating at or below reasonable capacity. There are electronic signs at various points before the exits to these roads that tell you the current toll so you can decide to go that way or not. I've seen it go up to over $15 on the one near my house!

    When I lived in New York (I just moved out here a few months ago) I had the EzPass for the NY Thruway, which was a little more nefarious. To get to any other city in New York in a reasonable manner, you have to use the Thruway, which is a toll road. I'm sure a whole lot more people in New York have EzPass than people in California have FasTrak. Of course, there are a lot more toll bridges and stuff in New York, which the EzPass also works on, which makes it, again, even more useful/essential than FasTrak since there aren't a whole lot of toll bridges around here (I can't think of a single one off the top of my head, while I regularly used them back in Buffalo.)

  • IMSI-Catcher (Score:2, Informative)

    by guruz ( 645678 ) on Tuesday November 18, 2008 @04:15AM (#25798881) Homepage
    By the way, since ages there is also a technique/device called IMSI-Catcher. http://en.wikipedia.org/wiki/IMSI-catcher [wikipedia.org]
  • Re:batteries ftw (Score:2, Informative)

    by Zymergy ( 803632 ) * on Tuesday November 18, 2008 @02:10PM (#25804915)
    As a HAM, I have met a few who have nifty gear able to tune into cell phones and their 'pings' or tower replies (from post-911 US cellphones) and a few of them have told me that there seems to be more than just pinging or tickling the towers going on. More than is needed to keep up the TX/RX channels open or for simply switching towers based on cell tower capacity and range to the handset.
    Others hinted that the removal of the battery does not fully prevent (post-911 US cellphones) from receiving radio frequency energy and replying uniquely (just like RFID tags do but cell phones have Much better antennas).
    Links that touch some on this topic:
    http://www.thenakedscientists.com/forum/index.php?topic=8068 [thenakedscientists.com]
    http://jya.com/cell-track.htm [jya.com]
    http://www.aclu.org/freespeech/gen/37748res20081112.html [aclu.org]
    http://allgpstracking.net/gpstracking/index.php/gpstracking/2006/03/12/how_gps_works_gps_tracking [allgpstracking.net]
    http://ezinearticles.com/?Cell-Phone-Location-Tracking-Information&id=782355 [ezinearticles.com]
    http://www.dslreports.com/forum/r21442821-Cell-phone-location-tracking-without-telcos-help [dslreports.com]
    http://arstechnica.com/news.ars/post/20081116-foia-docs-show-feds-can-lojack-mobiles-without-telco-help.html [arstechnica.com]
    http://www.danbrown.com/secrets/digital_fortress/cell_phones.html [danbrown.com]
    http://technology.timesonline.co.uk/tol/news/tech_and_web/article3945496.ece [timesonline.co.uk]
    Not to be a conspiracy theorist, but because RFID tags cost only a few cents each, why would similar capability NOT be incorporated into the chips of modern cell phones. Tear down an RFID tag, it is just a very very small semiconductor chip paired to a set of antennas between layers of opaque plastic tape an a sticker backing.
    (NOTE: In college, we had fun by carefully removing discovered RFID tags and 'repatriating' them onto different and unrelated merchandise at our local Wal-Mart Supercenter... good times..... not to be confused with the old tried and true bi-metallic strips that loss control departments use which set off the door antenna loops that we all walk through. But sticking one of those to your buddy's jacket made for a good laugh...)

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