How to fool a GPS
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0:02 - 0:04Something happened in the early morning hours
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0:04 - 0:08of May 2nd, 2000, that had a profound effect
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0:08 - 0:10on the way our society operates.
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0:10 - 0:13Ironically, hardly anyone noticed at the time.
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0:13 - 0:16The change was silent, imperceptible,
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0:16 - 0:19unless you knew exactly what to look for.
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0:19 - 0:21On that morning, U.S. President Bill Clinton
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0:21 - 0:24ordered that a special switch be thrown
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0:24 - 0:27in the orbiting satellites of the Global Positioning System.
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0:27 - 0:31Instantaneously, every civilian GPS receiver
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0:31 - 0:35around the globe went from errors the size of a football field
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0:35 - 0:39to errors the size of a small room.
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0:42 - 0:46It's hard to overstate the effect that this change
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0:46 - 0:49in accuracy has had on us.
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0:49 - 0:51Before this switch was thrown, we didn't have
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0:51 - 0:53in-car navigation systems giving turn-by-turn
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0:53 - 0:56directions, because back then, GPS couldn't tell you
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0:56 - 0:58what block you were on, let alone what street.
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0:58 - 1:02For geolocation, accuracy matters,
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1:02 - 1:05and things have only improved over the last 10 years.
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1:05 - 1:07With more base stations, more ground stations,
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1:07 - 1:10better receivers and better algorithms,
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1:10 - 1:13GPS can now not only tell you what street you are on,
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1:13 - 1:18but what part of the street.
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1:18 - 1:20This level of accuracy
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1:20 - 1:23has unleashed a firestorm of innovation.
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1:23 - 1:25In fact, many of you navigated here today
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1:25 - 1:29with the help of your TomTom or your smartphone.
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1:29 - 1:32Paper maps are becoming obsolete.
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1:32 - 1:36But we now stand on the verge of another revolution
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1:36 - 1:38in geolocation accuracy.
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1:38 - 1:41What if I told you that the two-meter positioning
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1:41 - 1:45that our current cell phones and our TomToms give us
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1:45 - 1:48is pathetic compared to what we could be getting?
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1:48 - 1:51For some time now, it's been known that if you pay attention
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1:51 - 1:54to the carrier phase of the GPS signal,
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1:54 - 1:56and if you have an Internet connection,
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1:56 - 1:59then you can go from meter level to centimeter level,
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1:59 - 2:02even millimeter-level positioning.
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2:02 - 2:05So why don't we have this capability on our phones?
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2:05 - 2:10Only, I believe, for a lack of imagination.
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2:10 - 2:13Manufacturers haven't built this carrier phase technique
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2:13 - 2:15into their cheap GPS chips
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2:15 - 2:17because they're not sure what the general public would do
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2:17 - 2:21with geolocation so accurate that you could pinpoint
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2:21 - 2:25the wrinkles in the palm of your hand.
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2:25 - 2:27But you and I and other innovators,
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2:27 - 2:31we can see the potential in this next leap in accuracy.
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2:31 - 2:34Imagine, for example, an augmented reality app
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2:34 - 2:37that overlays a virtual world to millimeter-level precision
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2:37 - 2:39on top of the physical world.
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2:39 - 2:42I could build for you a structure up here in 3D,
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2:42 - 2:45millimeter accurate, that only you could see,
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2:45 - 2:47or my friends at home.
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2:47 - 2:52So this level of positioning, this is what we're looking for,
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2:52 - 2:56and I believe that, within the next few years, I predict,
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2:56 - 3:01that this kind of hyper-precise, carrier phase-based positioning
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3:01 - 3:04will become cheap and ubiquitous,
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3:04 - 3:07and the consequences will be fantastic.
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3:07 - 3:11The Holy Grail, of course, is the GPS dot.
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3:11 - 3:14Do you remember the movie "The Da Vinci Code?"
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3:14 - 3:17Here's Professor Langdon examining a GPS dot,
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3:17 - 3:21which his accomplice tells him is a tracking device
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3:21 - 3:24accurate within two feet anywhere on the globe,
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3:24 - 3:27but we know that in the world of nonfiction,
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3:27 - 3:30the GPS dot is impossible, right?
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3:30 - 3:32For one thing, GPS doesn't work indoors,
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3:32 - 3:35and for another, they don't make devices quite this small,
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3:35 - 3:38especially when those devices have to relay
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3:38 - 3:41their measurements back over a network.
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3:41 - 3:43Well, these objections were perfectly reasonable
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3:43 - 3:46a few years ago, but things have changed.
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3:46 - 3:49There's been a strong trend toward miniaturization,
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3:49 - 3:53better sensitivity, so much so that, a few years ago,
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3:53 - 3:55a GPS tracking device looked like this clunky box
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3:55 - 3:58to the left of the keys.
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3:58 - 4:00Compare that with the device released just months ago
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4:00 - 4:04that's now packaged into something the size of a key fob,
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4:04 - 4:07and if you take a look at the state of the art
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4:07 - 4:09for a complete GPS receiver, which is only a centimeter
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4:09 - 4:11on a side and more sensitive than ever,
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4:11 - 4:15you realize that the GPS dot will soon move
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4:15 - 4:19from fiction to nonfiction.
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4:19 - 4:23Imagine what we could do with a world full of GPS dots.
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4:23 - 4:26It's not just that you'll never lose your wallet or your keys
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4:26 - 4:31anymore, or your child when you're at Disneyland.
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4:31 - 4:35You'll buy GPS dots in bulk, and you'll stick them on
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4:35 - 4:39everything you own worth more than a few tens of dollars.
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4:39 - 4:41I couldn't find my shoes one recent morning,
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4:41 - 4:45and, as usual, had to ask my wife if she had seen them.
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4:45 - 4:48But I shouldn't have to bother my wife with that kind of triviality.
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4:48 - 4:51I should be able to ask my house where my shoes are.
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4:51 - 4:53(Laughter)
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4:53 - 4:57Those of you who have made the switch to Gmail,
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4:57 - 4:59remember how refreshing it was to go from
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4:59 - 5:04organizing all of your email to simply searching it.
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5:04 - 5:08The GPS dot will do the same for our possessions.
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5:08 - 5:13Now, of course, there is a flip side to the GPS dot.
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5:13 - 5:15I was in my office some months back
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5:15 - 5:18and got a telephone call.
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5:18 - 5:21The woman on the other end of the line, we'll call her Carol,
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5:21 - 5:23was panicked.
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5:23 - 5:26Apparently, an ex-boyfriend of Carol's from California
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5:26 - 5:30had found her in Texas and was following her around.
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5:30 - 5:33So you might ask at this point why she's calling you.
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5:33 - 5:35Well, so did I.
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5:35 - 5:39But it turned out there was a technical twist to Carol's case.
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5:39 - 5:42Every time her ex-boyfriend would show up,
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5:42 - 5:46at the most improbable times and the most improbable locations,
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5:46 - 5:49he was carrying an open laptop,
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5:49 - 5:51and over time Carol realized that he had planted
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5:51 - 5:54a GPS tracking device on her car,
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5:54 - 5:57so she was calling me for help to disable it.
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5:57 - 5:59"Well, you should go to a good mechanic
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5:59 - 6:02and have him look at your car," I said.
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6:02 - 6:05"I already have," she told me.
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6:05 - 6:07"He didn't see anything obvious,
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6:07 - 6:11and he said he'd have to take the car apart piece by piece."
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6:11 - 6:14"Well then, you'd better go to the police," I said.
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6:14 - 6:17"I already have," she replied.
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6:17 - 6:19"They're not sure this rises to the level of harassment,
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6:19 - 6:23and they're not set up technically to find the device."
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6:23 - 6:25"Okay, what about the FBI?"
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6:25 - 6:29"I've talked to them too, and same story."
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6:29 - 6:30We then talked about her coming to my lab
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6:30 - 6:33and us performing a radio sweep of her car,
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6:33 - 6:36but I wasn't even sure that would work,
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6:36 - 6:38given that some of these devices are configured
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6:38 - 6:40to only transmit when they're inside safe zones
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6:40 - 6:43or when the car is moving.
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6:43 - 6:45So, there we were.
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6:45 - 6:48Carol isn't the first, and certainly won't be the last,
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6:48 - 6:53to find herself in this kind of fearsome environment,
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6:53 - 6:58worrisome situation caused by GPS tracking.
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6:58 - 7:00In fact, as I looked into her case,
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7:00 - 7:04I discovered to my surprise that it's not clearly illegal
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7:04 - 7:08for you or me to put a tracking device on someone else's car.
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7:08 - 7:12The Supreme Court ruled last month that a policeman
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7:12 - 7:16has to get a warrant if he wants to do prolonged tracking,
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7:16 - 7:20but the law isn't clear about civilians doing this to one another,
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7:20 - 7:22so it's not just Big Brother we have to worry about,
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7:22 - 7:26but Big Neighbor. (Laughter)
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7:26 - 7:30There is one alternative that Carol could have taken,
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7:30 - 7:36very effective. It's called the Wave Bubble.
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7:36 - 7:39It's an open-source GPS jammer,
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7:39 - 7:42developed by Limor Fried,
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7:42 - 7:45a graduate student at MIT, and Limor calls it
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7:45 - 7:49"a tool for reclaiming our personal space."
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7:49 - 7:52With a flip of the switch you create a bubble around you
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7:52 - 7:54within which GPS signals can't reside.
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7:54 - 7:56They get drowned out by the bubble.
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7:56 - 8:00And Limor designed this, in part, because, like Carol,
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8:00 - 8:02she felt threatened by GPS tracking.
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8:02 - 8:05Then she posted her design to the web,
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8:05 - 8:09and if you don't have time to build your own,
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8:09 - 8:10you can buy one.
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8:10 - 8:12Chinese manufacturers now sell thousands
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8:12 - 8:15of nearly identical devices on the Internet.
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8:15 - 8:19So you might be thinking, the Wave Bubble sounds great.
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8:19 - 8:23I should have one. Might come in handy if somebody ever puts a tracking device on my car.
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8:23 - 8:27But you should be aware that its use is very much illegal
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8:27 - 8:29in the United States.
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8:29 - 8:29And why is that?
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8:29 - 8:33Well, because it's not a bubble at all.
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8:33 - 8:35Its jamming signals don't stop at the edge
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8:35 - 8:37of your personal space or at the edge of your car.
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8:37 - 8:44They go on to jam innocent GPS receivers for miles around you. (Laughter)
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8:44 - 8:46Now, if you're Carol or Limor,
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8:46 - 8:49or someone who feels threatened by GPS tracking,
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8:49 - 8:53it might not feel wrong to turn on a Wave Bubble,
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8:53 - 8:57but in fact, the results can be disastrous.
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8:57 - 9:00Imagine, for example, you're the captain of a cruise ship
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9:00 - 9:02trying to make your way through a thick fog
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9:02 - 9:06and some passenger in the back turns on a Wave Bubble.
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9:06 - 9:09All of a sudden your GPS readout goes blank,
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9:09 - 9:12and now it's just you and the fog
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9:12 - 9:14and whatever you can pull off the radar system
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9:14 - 9:18if you remember how to work it.
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9:18 - 9:24They -- in fact, they don't update or upkeep lighthouses
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9:24 - 9:28anymore, and LORAN, the only backup to GPS,
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9:28 - 9:31was discontinued last year.
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9:31 - 9:36Our modern society has a special relationship with GPS.
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9:36 - 9:38We're almost blindly reliant on it.
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9:38 - 9:41It's built deeply into our systems and infrastructure.
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9:41 - 9:45Some call it "the invisible utility."
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9:45 - 9:49So, turning on a Wave Bubble might not just cause inconvenience.
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9:49 - 9:53It might be deadly.
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9:53 - 9:57But as it turns out, for purposes of protecting your privacy
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9:57 - 10:01at the expense of general GPS reliability,
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10:01 - 10:03there's something even more potent
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10:03 - 10:07and more subversive than a Wave Bubble,
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10:07 - 10:10and that is a GPS spoofer.
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10:10 - 10:13The idea behind the GPS spoofer is simple.
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10:13 - 10:17Instead of jamming the GPS signals, you fake them.
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10:17 - 10:20You imitate them, and if you do it right, the device
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10:20 - 10:23you're attacking doesn't even know it's being spoofed.
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10:23 - 10:25So let me show you how this works.
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10:25 - 10:28In any GPS receiver, there's a peak inside
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10:28 - 10:30that corresponds to the authentic signals.
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10:30 - 10:33These three red dots represent the tracking points
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10:33 - 10:36that try to keep themselves centered on that peak.
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10:36 - 10:39But if you send in a fake GPS signal,
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10:39 - 10:44another peak pops up, and if you can get these two peaks
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10:44 - 10:48perfectly aligned, the tracking points can't tell the difference,
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10:48 - 10:52and they get hijacked by the stronger counterfeit signal,
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10:52 - 10:56with the authentic peak getting forced off.
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10:56 - 10:58At this point, the game is over.
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10:58 - 11:01The fake signals now completely control this GPS receiver.
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11:01 - 11:03So is this really possible?
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11:03 - 11:05Can someone really manipulate
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11:05 - 11:07the timing and positioning of a GPS receiver
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11:07 - 11:09just like that, with a spoofer?
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11:09 - 11:12Well, the short answer is yes.
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11:12 - 11:14The key is that civil GPS signals
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11:14 - 11:15are completely open.
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11:15 - 11:19They have no encryption. They have no authentication.
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11:19 - 11:23They're wide open, vulnerable to a kind of spoofing attack.
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11:23 - 11:25Even so, up until very recently,
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11:25 - 11:28nobody worried about GPS spoofers.
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11:28 - 11:30People figured that it would be too complex
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11:30 - 11:33or too expensive for some hacker to build one.
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11:33 - 11:37But I, and a friend of mine from graduate school,
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11:37 - 11:39we didn't see it that way.
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11:39 - 11:41We knew it wasn't going to be so hard,
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11:41 - 11:43and we wanted to be the first to build one
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11:43 - 11:45so we could get out in front of the problem
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11:45 - 11:49and help protect against GPS spoofing.
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11:49 - 11:53I remember vividly the week it all came together.
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11:53 - 11:56We built it at my home, which means that
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11:56 - 12:01I got a little extra help from my three-year-old son Ramon.
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12:01 - 12:03Here's Ramon — (Laughter) —
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12:03 - 12:07looking for a little attention from Dad that week.
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12:07 - 12:09At first, the spoofer was just a jumble of cables
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12:09 - 12:12and computers, though we eventually got it packaged
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12:12 - 12:13into a small box.
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12:13 - 12:16Now, the Dr. Frankenstein moment,
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12:16 - 12:19when the spoofer finally came alive
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12:19 - 12:22and I glimpsed its awful potential,
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12:22 - 12:24came late one night when I tested the spoofer
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12:24 - 12:26against my iPhone.
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12:26 - 12:28Let me show you some actual footage from that
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12:28 - 12:30very first experiment.
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12:30 - 12:34I had come to completely trust this little blue dot
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12:34 - 12:35and its reassuring blue halo.
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12:35 - 12:36They seemed to speak to me.
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12:36 - 12:41They'd say, "Here you are. Here you are." (Laughter)
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12:41 - 12:44And "you can trust us."
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12:44 - 12:49So something felt very wrong about the world.
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12:49 - 12:52It was a sense, almost, of betrayal,
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12:52 - 12:56when this little blue dot started at my house,
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12:56 - 12:57and went running off toward the north
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12:57 - 13:01leaving me behind. I wasn't moving.
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13:01 - 13:05What I then saw in this little moving blue dot
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13:05 - 13:08was the potential for chaos.
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13:08 - 13:12I saw airplanes and ships veering off course, with the captain
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13:12 - 13:17learning only too late that something was wrong.
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13:17 - 13:19I saw the GPS-derived timing
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13:19 - 13:21of the New York Stock Exchange
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13:21 - 13:23being manipulated by hackers.
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13:23 - 13:26You can scarcely imagine the kind of havoc
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13:26 - 13:28you could cause if you knew what you were doing
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13:28 - 13:32with a GPS spoofer.
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13:32 - 13:37There is, though, one redeeming feature
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13:37 - 13:39of the GPS spoofer.
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13:39 - 13:44It's the ultimate weapon against an invasion of GPS dots.
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13:44 - 13:47Imagine, for example, you're being tracked.
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13:47 - 13:50Well, you can play the tracker for a fool,
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13:50 - 13:52pretending to be at work when you're really on vacation.
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13:52 - 13:55Or, if you're Carol, you could lure your ex-boyfriend
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13:55 - 13:57into some empty parking lot
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13:57 - 13:59where the police are waiting for him.
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13:59 - 14:04So I'm fascinated by this conflict, a looming conflict,
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14:04 - 14:07between privacy on the one hand
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14:07 - 14:11and the need for a clean radio spectrum on the other.
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14:11 - 14:14We simply cannot tolerate GPS jammers and spoofers,
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14:14 - 14:18and yet, given the lack of effective legal means
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14:18 - 14:22for protecting our privacy from the GPS dot,
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14:22 - 14:24can you really blame people for wanting to turn them on,
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14:24 - 14:26for wanting to use them?
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14:26 - 14:29I hold out hope that we'll be able to reconcile
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14:29 - 14:32this conflict with some sort of,
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14:32 - 14:38some yet uninvented technology.
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14:38 - 14:41But meanwhile, grab some popcorn,
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14:41 - 14:43because things are going to get interesting.
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14:43 - 14:44Within the next few years,
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14:44 - 14:49many of you will be the proud owner of a GPS dot.
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14:49 - 14:51Maybe you'll have a whole bag full of them.
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14:51 - 14:54You'll never lose track of your things again.
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14:54 - 14:58The GPS dot will fundamentally reorder your life.
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14:58 - 15:01But will you be able to resist the temptation
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15:01 - 15:04to track your fellow man?
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15:04 - 15:06Or will you be able to resist the temptation
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15:06 - 15:09to turn on a GPS spoofer or a Wave Bubble
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15:09 - 15:12to protect your own privacy?
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15:12 - 15:16So, as usual, what we see just beyond the horizon
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15:16 - 15:19is full of promise and peril.
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15:19 - 15:22It'll be fascinating to see how this all turns out.
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15:22 - 15:25Thanks. (Applause)
- Title:
- How to fool a GPS
- Speaker:
- Todd Humphreys
- Description:
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Todd Humphreys forecasts the near-future of geolocation when millimeter-accurate GPS "dots" will enable you to find pin-point locations, index-search your physical possessions ... or to track people without their knowledge. And the response to the sinister side of this technology may have unintended consequences of its own. (Filmed at TEDxAustin.)
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 15:45
Thu-Huong Ha edited English subtitles for How to fool a GPS | ||
Thu-Huong Ha approved English subtitles for How to fool a GPS | ||
Thu-Huong Ha edited English subtitles for How to fool a GPS | ||
Morton Bast accepted English subtitles for How to fool a GPS | ||
Morton Bast edited English subtitles for How to fool a GPS | ||
Joseph Geni added a translation |