Entries Tagged "full-body scanners"

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Camera that Sees Under Clothes

Interesting:

A British company has developed a camera that can detect weapons, drugs or explosives hidden under people’s clothes from up to 25 meters away in what could be a breakthrough for the security industry.

The T5000 camera, created by a company called ThruVision, uses what it calls “passive imaging technology” to identify objects by the natural electromagnetic rays — known as Terahertz or T-rays — that they emit.

The high-powered camera can detect hidden objects from up to 80 feet away and is effective even when people are moving. It does not reveal physical body details and the screening is harmless, the company says.

If this is real, it seems much less invasive than backscatter X ray.

Posted on March 17, 2008 at 6:30 AMView Comments

Conversation with Kip Hawley, TSA Administrator (Part 2)

This is Part 2 of a five-part series. Link to whole thing.

BS: I hope you’re telling the truth; screening is a difficult problem, and it’s hard to discount all of those published tests and reports. But a lot of the security around these checkpoints is about perception — we want potential terrorists to think there’s a significant chance they won’t get through the checkpoints — so you’re better off maintaining that the screeners are better than reports indicate, even if they’re not.

Backscatter X-ray is another technology that is causing privacy concerns, since it basically allows you to see people naked. Can you explain the benefits of the technology, and what you are doing to protect privacy? Although the machines can distort the images, we know that they can store raw, unfiltered images; the manufacturer Rapiscan is quite proud of the fact. Are the machines you’re using routinely storing images? Can they store images at the screener’s discretion, or is that capability turned off at installation?

KH: We’re still evaluating backscatter and are in the process of running millimeter wave portals right alongside backscatter to compare their effectiveness and the privacy issues. We do not now store images for the test phase (function disabled), and although we haven’t officially resolved the issue, I fully understand the privacy argument and don’t assume that we will store them if and when they’re widely deployed.

BS: When can we keep our shoes on?

KH: Any time after you clear security. Sorry, Bruce, I don’t like it either, but this is not just something leftover from 2002. It is a real, current concern. We’re looking at shoe scanners and ways of using millimeter wave and/or backscatter to get there, but until the technology catches up to the risk, the shoes have to go in the bin.

BS: This feels so much like “cover your ass” security: you’re screening our shoes because everyone knows Richard Reid hid explosives in them, and you’ll be raked over the coals if that particular plot ever happens again. But there are literally thousands of possible plots.

So when does it end? The terrorists invented a particular tactic, and you’re defending against it. But you’re playing a game you can’t win. You ban guns and bombs, so the terrorists use box cutters. You ban small blades and knitting needles, and they hide explosives in their shoes. You screen shoes, so they invent a liquid explosive. You restrict liquids, and they’re going to do something else. The terrorists are going to look at what you’re confiscating, and they’re going to design a plot to bypass your security.

That’s the real lesson of the liquid bombers. Assuming you’re right and the explosive was real, it was an explosive that none of the security measures at the time would have detected. So why play this slow game of whittling down what people can bring onto airplanes? When do you say: “Enough. It’s not about the details of the tactic; it’s about the broad threat”?

KH: In late 2005, I made a big deal about focusing on Improvised Explosives Devices (IEDs) and not chasing all the things that could be used as weapons. Until the liquids plot this summer, we were defending our decision to let scissors and small tools back on planes and trying to add layers like behavior detection and document checking, so it is ironic that you ask this question — I am in vehement agreement with your premise. We’d rather focus on things that can do catastrophic harm (bombs!) and add layers to get people with hostile intent to highlight themselves. We have a responsibility, though, to address known continued active attack methods like shoes and liquids and, unfortunately, have to use our somewhat clunky process for now.

BS: You don’t have a responsibility to screen shoes; you have one to protect air travel from terrorism to the best of your ability. You’re picking and choosing. We know the Chechnyan terrorists who downed two Russian planes in 2004 got through security partly because different people carried the explosive and the detonator. Why doesn’t this count as a continued, active attack method?

I don’t want to even think about how much C4 I can strap to my legs and walk through your magnetometers. Or search the Internet for “BeerBelly.” It’s a device you can strap to your chest to smuggle beer into stadiums, but you can also use it smuggle 40 ounces of dangerous liquid explosive onto planes. The magnetometer won’t detect it. Your secondary screening wandings won’t detect it. Why aren’t you making us all take our shirts off? Will you have to find a printout of the webpage in some terrorist safe house? Or will someone actually have to try it? If that doesn’t bother you, search the Internet for “cell phone gun.”

It’s “cover your ass” security. If someone tries to blow up a plane with a shoe or a liquid, you’ll take a lot of blame for not catching it. But if someone uses any of these other, equally known, attack methods, you’ll be blamed less because they’re less public.

KH: Dead wrong! Our security strategy assumes an adaptive terrorist, and that looking backwards is not a reliable predictor of the next type of attack. Yes, we screen for shoe bombs and liquids, because it would be stupid not to directly address attack methods that we believe to be active. Overall, we are getting away from trying to predict what the object looks like and looking more for the other markers of a terrorist. (Don’t forget, we see two million people a day, so we know what normal looks like.) What he/she does; the way they behave. That way we don’t put all our eggs in the basket of catching them in the act. We can’t give them free rein to surveil or do dry-runs; we need to put up obstacles for them at every turn. Working backwards, what do you need to do to be successful in an attack? Find the decision points that show the difference between normal action and action needed for an attack. Our odds are better with this approach than by trying to take away methods, annoying object by annoying object. Bruce, as for blame, that’s nothing compared to what all of us would carry inside if we failed to prevent an attack.

Part 3: The no-fly list

Posted on July 31, 2007 at 6:12 AMView Comments

Ambient Radiation Sensors

Here’s a piece of interesting research out of Ohio State: it’s a passive sensor that could be cheaper, better, and less intrusive than technologies like backscatter X-rays:

“Unlike X-ray machines or radar instruments, the sensor doesn’t have to generate a signal to detect objects ­ it spots them based on how brightly they reflect the natural radiation that is all around us every day.”

“It’s basically just a really bad tunnel diode,” he explained. “I thought, heck, we can make a bad diode! We made lots of them back when we were figuring out how to make good ones.”

First millimeter-wave detection systems, and now this. There’s some interesting research in remote sensing going on, and there are sure to be some cool security applications.

Posted on August 24, 2005 at 8:17 AMView Comments

Backscatter X-Ray Technology

Backscatter X-ray technology is a method of using X rays to see inside objects. The science is complicated, but the upshot is that you can see people naked:

The application of this new x-ray technology to airport screening uses high energy x-rays that are more likely to scatter than penetrate materials as compared to lower-energy x-rays used in medical applications. Although this type of x-ray is said to be harmless it can move through other materials, such as clothing.

A passenger is scanned by rastering or moving a single high energy x-ray beam rapidly over their form. The signal strength of detected backscattered x-rays from a known position then allows a highly realistic image to be reconstructed. Since only Compton scattered x-rays are used, the registered image is mainly that of the surface of the object/person being imaged. In the case of airline passenger screening it is her nude form. The image resolution of the technology is high, so details of the human form of airline passengers present privacy challenges.

EPIC’s “Spotlight on Security” page is an excellent resource on this issue.

The TSA has recently announced a proposal to use these machines to screen airport passengers.

I’m not impressed with this security trade-off. Yes, backscatter X-ray machines might be able to detect things that conventional screening might miss. But I already think we’re spending too much effort screening airplane passengers at the expense of screening luggage and airport employees…to say nothing of the money we should be spending on non-airport security.

On the other side, these machines are expensive and the technology is incredibly intrusive. I don’t think that people should be subjected to strip searches before they board airplanes. And I believe that most people would be appalled by the prospect of security screeners seeing them naked.

I believe that there will be a groundswell of popular opposition to this idea. Aside from the usual list of pro-privacy and pro-liberty groups, I expect fundamentalist Christian groups to be appalled by this technology. I think we can get a bevy of supermodels to speak out against the invasiveness of the search.

News article

Posted on June 9, 2005 at 1:04 PMView Comments

Sidebar photo of Bruce Schneier by Joe MacInnis.