Your Cell Phone Is Tracking You 453
PollGuy writes "I had never heard until this article in the New York Times (sacrifice of first born required) about services that let regular people track the locations of other regular people via their cell phones. Nor this: 'A federal mandate that wireless carriers be able to locate callers who dial 911 automatically by late 2005 means that millions of phones already keep track of their owners' whereabouts.'"
many phones can disable this (Score:4, Informative)
I think it's pretty easy for the phone to tell if you're dialing 911 or not, so when you turn it off, it probably means it's off.
e911 (Score:1, Informative)
I discovered how E911(the location program) works and that i could use my very phone to tell me my last location! Very incredible... yet i could see hackers taking advantage of this
Like Google Registration Safe Link .. (Score:1, Informative)
Your Cell Phone is tracking you [nytimes.com]
google link for those without children to spare (Score:2, Informative)
Lost? Hiding? Your Cellphone Is Keeping Tabs [nytimes.com]
On the train returning to Armonk, N.Y., from a recent shopping trip in Manhattan with her friends, Britney Lutz, 15, had the odd sensation that her father was watching her.....
Re:Triangulation (Score:5, Informative)
GPS allows one person to instantly pinpoint you to within two meters. Information this easily obtained is potentially valuable to abusers.
old news (Score:2, Informative)
You've always been able to locate the position of a cell phone as it's making a call via triangulation with 2 towers. This is nothing new.
Re:Non-GPS-enabled phones... (Score:5, Informative)
I say this with some authority, as I used to be working one floor above the guys developing the MPS (Mobile Positioning System) solution. That was, ummm, about four or five years ago. So no, this is nothing new... these aren't the droids you're looking for; move along.
part of "phase 2" 911 services (Score:3, Informative)
Phase II requires more precise location information be provided to the PSAP. Phase II requires the wireless service provider to provide the call back telephone number of the 9-1-1 caller, cell tower location, cell sector (antenna orientation) information, plus longitude and latitude (X, Y) information. Phase II E9-1-1 services exist today in a handful of locations, by a few wireless service providers, but these numbers will grow.
Anyone know how to use it? (Score:2, Informative)
Here's to sweethearts and wives, may they never meet.
Re:That's weird... (Score:1, Informative)
It's all described here... (Score:5, Informative)
Only works with Nextel now and free until the end of the year.
Another reason to hate Nextel for me. After having a boss that gave us all Nextels and having managers that would use the Instant-On feature to speak to us night and day (10:26pm Manager: "Hello, Hello, are you there?? The mail server seems to be a little slow, are you there?"), I will never consider Nextel again. I'm scarred for life!!
Re:Triangulation (Score:4, Informative)
To pin someone down in 2 dimensions (that is, not considering height) you need 3 towers.
Picture it this way:
If they want to know your height they would need at least 4 towers. Any towers beyond what they need will add to the accuracy of finding your exact location. It is common for triangulation to use 7 or 8 points in order to increase the accuracy.
Re:Limited to base station accuracy only? (Score:4, Informative)
Re:Triangulation (Score:5, Informative)
When a cellular phone is in coverage, which is to say when you can actually use your phone to call 911 in the first place, there are usually at least three base-stations which your cellular phone can contact (though it only uses the strongest signal for obvious reasons).
It is true that it takes non-trivial effort to implement triangulation based upon the signal strength of your cellular phone, but it also would take non-trivial effort to put a GPS solution onto a cellular phone. What is more important is which system is more precise, accurate, and reliable -- that would be GPS.
don't believe the hype!! (Score:1, Informative)
Cell Phoney Tracking (Score:5, Informative)
Cell phone tracking is currently available, and will always be available even without GPS. As you travel your cell phone communicates to various cell phone towers along the path.
Cell phone companies will provide Public Safety agencies with "tower" information and subscriber information for emergency situations. With the tower information, it will provide about a one mile radius to search if needed.
GPS ability is available to some beta site dispatch centers. Cell phone/GPS information is provided when 911 is dialed. Landline 911 will provide location, phone number(s) and subscriber information. Very important info for responding agencies.
GPS ability is very important to Public Safety agencies. I lost count of the number of times "we" were unable to find a cell phone caller. 911 cell phone callers often have a dificult time giving their location, especially in unfamilar areas. I've taken calls where the caller is in a trapped in a ditch or injured in the middle of nowhere. I have also taken calls where a victim or injured person has called and for one reason or another is unable to give the location. Dead battery, poor reception site, lost consciousness etc.
Put yourself or a loved one in that scenerio and think about it. You have to think of the worst case scenerio, it happens daily.
I leave my GPS data on all the time, never knowing when I myself will be involved in an emergency.
I have nothing to hide, and couldn't care less if anybody new where I was located. With hundreds of cell phones being used in any one region, the thought of somebody caring about your location is quite unrealistic.
The whole basis of the GPS cell phone data is in the interest of public safety. To assist you when you need it most.
I'd be more afraid of criminals my personal data for identity theft.
Each credit card/atm/club card transaction is telling somebody where you are and what you are purchasing. Nobody seems to be bothered with that.
I don't have an account, not because i'm a coward. I just have the desire to post here often. I'm also paranoid that somebody is going to steal my personal information.
-Ant-
Re:That's weird... (Score:5, Informative)
My understanding at this point is digital phones are easier to track because they're always in communication with the towers, but older analog-only phones are only trackable when they're being used, because they can go passive. I may be mistaken on that.
Re:Non-GPS-enabled phones... (Score:5, Informative)
I think you've missed the point. Your boss or parent or boyfriend (or stalker) doesn't have the ability to triangulate on you -- it's not an easy thing. If the police do it, there'll be records, and it probably falls under wiretapping statutes. The issue here is: There are no legal guidelines for the ubiquitous surveilliance mentioned in the article.
High standards? (Score:5, Informative)
They've used OnStar to eavesdrop on people. The only reason that go shut down is because the person couldn't use OnStar to call for help - which will be solvable by the cops by promising to forward any such requests immediately to the OnStar system.
In '93 they were wiretapping all public phones in 'bad' areas in my town. I don't think they even bothered to get a warrant, which is why it made the papers.
Feds have *never* turned down an application for a warrant to themselves in Patriot related matters - which is not solely related to 'terrorist' activity - even when terrorist activity was rather loosely defined. They're now using it for domestic crimes.
The federal DB of records on every citizen is moving forward, all boat registration, car registration, credit records, etc.
Yeah: "Trust us, we're from the Gubbmint", sure, sure - as long as high standards are used, it shouldn't be a problem. As long as people follow the law, you should have no hackers attacking your computer systems, no viruses will be written, and all code won't cause catastrophic failure on your machines, or data corruption.
Must be nice to live in fantasy land.
-- Ender, Duke_of_URL
Re:Triangulation (Score:5, Informative)
With GSM base stations you also to consider the fact that a cell is divided into several sectors, which are nothing more than oriented antenas that face a certain direction. This means that in many cases you only need data from 2 base stations, because (as you mentioned) you get cross points for 2 circles, but you can discard one point as it doesn't lie in the sector my phone is in.
This also means that often records from a single base station are enough to prove me lying. If you take a micro-cell for example (having a range of up to a kilometer, I think), you can actually see whether I was north of the cell, like I'm claiming, or that I was in fact to the south, where a crime was commited...
Hope this makes any sense, I have to get some sleep...
Re:Indeed... (Score:5, Informative)
A <== A cell phone base station.
________ ________
/ \/ \ Here you can see how this thing works.
/
/ / \ \ are within the range of the circle
/ . / \ . \ around it away from it. it knows it by
\ 1 A \____/_A_ / measuring the strength of your phone's
\
\ / \/ \ / The same way, base station 2 knows
\____/___/\_______\/ your distance from it, too and can draw
/ . \ a circle, as well. Now, with these two
\ A / base stations we know that the phone
\ / user is in one of the two intersections
\ 3 / of the circles around base stations one
\________/ and two.
Then there is the base station three. It
only needs to know that its signal is not strong enough to reach the
northern intersection of circles of base stations 1 and 2. That way we
know that the user must be in the southern one of the intersections of
circles drawn by base stations 1 and 2. Please note that in this drawing
base station 3's circle doesn't tell the distance from the phone user,
but the maximum possible range it can reach. (Because I didn't think
when I drew the pic.)
Even if the distance info isn't that accurate (meaning that you're using
an old crappy analog cell phone most of you americans use), we can still
plot your location quite exactly. If we just know that the phone is
within the maximum ranges of all three base stations pictured here, the
phone must be in the area I've marked with X letters. Often there are
even more than three base stations around you. That makes getting the
location info even more accurate. So, in a city you can be located with
an error marging of only few tens of meters. In suburbs the error
margin is at least here in Finland some 500m. (Actually less, but this
distance is used by the cell phone company to make sure the phone is
100% surely in the area shown.
Here it just became legal to see where your kids' phones are going if
you've signed a contract in advance. You go to internet and give your
username and password. Then the site will plot your kid's location on
a map.
I'm really surprised that this many of the
advance. Here in Europe right about everyone knows that. And has known
since something like 1995 or so. Tracking people by their cell phones
has been possible as long as there has been cell phones.
Guess your government and media hasn't for some "odd" reason wanted its
servants to know too much of what is possible.
I don't see what damn problem it is if you can be located if you're
dying in a pit. I remember seeing in the TV program 911 how one woman
almost died when she didn't know where she was while she called the 911
from a landlined phone. I didn't understand why they didn't just look
where she was calling from and send an ambulance there. It only takes
about 0,0000000(and so on)0001 seconds to find out that info, not a
minute like in the hollywood movies.
The info about who's calling can be asked from a telephone company. It
has to know it to be able to bill someone for calling.
Before you had to know where you are to get an ambulance. If you didn't
know, you died. Cute. Now you just need to call 911 or 112 depending on
what continent you're in and say "I'm dying. Get me to hospital." and
the ambulance will come.
poor parenting and false security (Score:2, Informative)
Anyways, back to the topic at hand. While the original "Find Friend" type services are generally harmless as long as the involved parties consent, and while similar use for real safety issues (i.e. firefighters on duty) is also generally harmless, further use of these services for other purposes than finding your mates in a discoteque queue or finding firefighters is obviously disturbing from a privacy standpoint.
It's unfortunate to see that these cellphones make parents think that they will make their kids tell the truth, etc. At the same time, it's unfortunate that the presumption of trust and goodwill is taken away from these children; children learn that they can't be trusted before they may or may not have done anything.
It's also unfortunate that parents are led to believe that if they think their kid is in danger, all they have to do is push a button and see where the kid is positioned and voila! Kid is found. It's not that simple. This quote was disturbing: Jason Pratt said there were advantages to being watched. He no longer has to call his mother to let her know where he is. Instead, she can press a "locate" button on her phone and see for herself. Not only do these devices break down communication between parents and children, communication which is necessary to provide good, trusting relationships, it gives a false sense of security. Jason could be mugged, his phone taken away from him. If he had told mommy where he was and where he was going, it would be easier to find Jason than chasing the cellphone which the mugger probably tossed into a trash bin some random location.
More than ever, technological devices are replacing good old fashioned parenting. OK, I don't have brats myself, but I used to be one. I was taught good common sense things like don't talk to strangers, call if we're going to be late home (and don't be afraid to call collect), stick to known streets and paths, be aware of your surroundings, etc. I never thought it was so diffucult to stick to. I did OK and so have a lot of other children from "my generation" (no, I'm not that old). Has society become so much worse today that kids have to be put under surveillance? Why don't good old fashioned rules work anymore?
If you have a kid that wanders away from "approved" areas or lies about which train she may have taken, then you have a problem that goes beyond what surveillance devices can solve. Somewhere, you f-ed up as a parent.
Another issue is the fantasy that these devices could be used to find kidnapped/missing kids. Problem #1 - most kidnappings are done by family members, not strangers. Technology may find the kid, but it doesn't resolve the real issue. Problem #2 - even if the kidnapping was at the hands of a stranger, the stranger (and even the family member) could throw away or destroy the GPS device.
Another thing is that children may be present in the "safety zone" or whatever you want to call it; parents check up on their kids and since they're in an area that is "OK" they let it be. Well, a kid may be in the "safety zone" but locked up in the pedophile neighbor's garage. So much good the cellphone has done!
Yet another issue is that this teaches children to accept surveillance, whether willingly or unwillingly. To go even further, "good kids think that surveillance is good." "If you don't accept us watching over you, then you're a criminal with something to hide." Again, this takes away the presumption of innocence, and children learn that their parents don't trust them from day one. What kind of society becomes created when nobody trusts the other?
Re:This just in... (Score:5, Informative)
Re:Non-GPS-enabled phones... (Score:2, Informative)
The actual resolution can be as good as +- 1 yard.
I've done this. I can do it again. Hey, I can even set up a script that will send me an SMS when my teenahe daughter gets too close to the wrong part of town!
Tracking your cell phone. (Score:5, Informative)
+ signal strengths measured at two or more towers,
+ the so-called timing advance measurements,
+ measurements done over several frequencies (GSM uses frequency hopping).
Usually, in urban areas, we'd get the location within 10 meters. In rural areas, it was more like 100 meter. It was a bit of a hassle to order the system to start the tracking, and there was no nice user interface for the resulting trace data. We made a few hacks to make our lives easier. Some of those hacks still lives... Today, the radio base stations comes with the option of a built-in GPS. That makes the position of the base statio very well known (that was a problem back in 1999). You can still use the measurement reports from the cell-phone to get the current location (cell-phones have to make measurement reports, or they won't work in the system). You don't need to have GPS capability in the cell-phone. But if you do, and it reports coordinates that doesn't agree with known data frpm the base stations, the cell-phones data will be ignored, and real measurements will be used. The user interfaces of today are mcu better. Using the IMSI (International Mobile Subscriber Identity) or even the equipment identity number, you can order the system to log all movements of the cell-phone. The only way to avoid this, is to keep the battery out of the cell-phone, and only put it in when you need the service.
How it works for 911 (Score:3, Informative)
Re:Non-GPS-enabled phones... (Score:4, Informative)
It's probably already too late. If you don't want Big Brother (or your parents, employer, or a deranged stalker) tracking your whereabouts 24/7, turn your damn cell phone off when you aren't making a call or expecting a call.
Re:This just in... (Score:3, Informative)
Wow! You think anyone has access to this information on cell phones??
Wow! You can think of a practical situation where the location on your cell will be used against you??
Re:Non-GPS-enabled phones... (Score:3, Informative)
The first Supreme Court ruling on wiretapping, Olmstead vs. US, was issued in 1928. The Olmstead ruling held that warrantless wiretapping was Constitutional, and that evidence gained thereby was admissable. The first limits on wiretapping came in 1934 when the Federal Communications act was passed, which prohibited private parties from tapping phone conversations unless one or more of the parties involved consented. While the two Nardonne v. US rulings (1937 and 1939) further limited the admissibility of evidence obtained via wiretap, the Olmstead ruling remained largely in effect until it was overturned by Katz v. US in 1967.
Re:Indeed... (Score:5, Informative)
If the phone is in idle mode, i.e. not in call, it will monitor the surrounding cells and select (called camping) the cell with the best selection value which is a function of signal strength and some other parameters set by the network. Also, cells will be grouped into location areas, also known as paging areas, and it is only when the mobile moves from one area to another that it transmits to the network to inform that it has moved to a new location area. Therefore, normally it is only possible to track the user to a location area, which may span a number of cells, each of which could be upto ~35km in radius.
There is a extension called EOTD which uses neigbour cell timing and signal strength estimations to calculate positioning information, but this requires extra support in the base stations and mobile, and isn't widely deployed. Also, since the mobile has to make measurements and report them to the network, this is only done if the network requests it; it would drain your battery to constantly report position.
In dedicate mode, when making a call, the mobile does report signal strengths of the top 6 neigbour cells to the network reasonably frequently, and it would be possible to track a user in a call as you describe, but that's pretty obvious IMHO - you want to make a phone call, so something has to know roughly where you are.
I don't dispute that the network knows where you are, but the average case has a lot lower resolution than you imply.
Re:This just in... (Score:4, Informative)
Re:TWIT... Forget tracking, hackers can listen in! (Score:5, Informative)
They get MUCH closer than that. (Score:3, Informative)
In addition to signal strength (which varies not just with distance but with transmission path artifacts, like trees and moisture), digital cellphone base stations keep track of out-and-back signal turnaround time - to an extremely fine granularity. They do this to assign timeslots for the phone-to-tower signals, to make maximum use of the channel.
Assuming the strongest path is the line-of-sight path (rather than, say, a bounce off a building), this gives them the distance to the phone, within a few feet. (This assumption is usually true.)
The geometry is the same. But with the distance information added, each tower can put the phone on a sphere of a particular radius around the tower. Assuming the phone is on or near roughly flat ground (not in an aircraft or climing a steep mountain - also usually true), that becomes a circle where it intersects the ground, with an uncertainty stripe width of a few feet.
Add a second tower and you get two intersecting circles - and two lozenge-shaped patches where they intersect. A third cell tower can tell you whitch patch (and shrink it further by cutting off the long ends).
The advantage of adding a GPS to the phone is that you only need a SINGLE cell tower to interrogate the GPS in order to locate the user to GPS acuracy. This is handy for trouble calls where only one or two cells can reach the phone, so you don't have to dispatch two ambulances (for two cells) or a search plane (for one).
The distance information is available any time the phone is on. When it's switched on, switched off, and about every five minutes in between, it checkes in with the cell system. (Get one of those "cell-phone jewels", a blinky antenna, or a battery pack with a blinks-when-transmitting gadget to see when. Or just lay the antenna on a cheap transistor radio tuned to a quiet spot and listen to the pops and buzzes.) This is to update the system's database so it knows where to send incoming calls. But it also updates the distance information necessary to locate the phone within a few feet.
This information has been available to law enforcement for a while.
No, that would be distance-based "triangulation". (Score:5, Informative)
No, that would probably be the cell-based system.
It's not really "triangulation". Triangulation uses the observed DIRECTION of the signal, locating the transmitter on a (hopefully) narrow fan based at the reciever. Two receivers locate the transmitter where the "beams" intersect, and the "beams" plus the baseline between the receivers form a triangle.
This system uses the round-trip transit time, much like radar, to locate the transmitter on a circle around each "receiver" (actually an active transciever), putting the transmitter where the circles intersect. (You still get the triangle of the locations. But it's a different system than "triangulation".)
You can also locate the transmitter if all, or all-but-one, of the receivers is passive, but they can compare notes on signal arrival time.
If all are passive, two receivers locate the transmitter on a hyperbola, three narrow it to two intersecting hyperbolas, four pin it (or three if one or more can distinguish the two intersections by antenna sectoring).
If one "receiver" is active, it locates the transmitter on a circle, the second adds a hyperbola intersecting the circle at two points, the third (or sector antennas) adds another hyperbola that intersects differently with the circle to distinguish the points. (This is much like LORAN.)
The accuracy depends on the angles, the accuracy of the arrival-time measurements, and the accuracy of the knowlege of the locations of the base stations. Ground-based systems have an advantage in the angles (being roughly in a plain with the transmitter). They also have better knowlege of antenna location than orbiting satellites. Both have comparable time bases (based on atomic-clock-referenced Stratum-III clocks in the cell base stations and atomic clocks in the satellites). GPS was optimized for location tracking so it MAY measure the signal arrival time more accurately. But that's a "maybe", since the base stations need it accurate, too, and can throw more electronics at the problem than the portable GPS receiver. (Anybody have the real stats?)
Now that selective availability is turned off GPS MIGHT be as accurate as cell systems. But it's still fighting some handicaps, so I'd be surprised if it's better.
Re:Rape button (Score:5, Informative)
Many phones will automatically dial 9-1-1 and transmit your GPS location (if so equipped) if you simply hold down on the '9' button for a five seconds or more. This will generally work even if you don't have a contract for cell service and can't place or receive normal calls.
Re:Triangulation (Score:3, Informative)
2. There is no distance data available.
This gives them very good information on where you are with two towers. Plot the two sectors, you're somewhere in the overlap. Three towers gives them slightly better data, four only marginally better then three, and on and on. Moving, especially over a long period of time, gives them better data too.