OnStar will soon include the ability for the police to shut off your engine remotely. Buses are getting the same capability, in case terrorists want to re-enact the movie Speed. The Pentagon wants a kill switch installed on airplanes, and is worried about potential enemies installing kill switches on their own equipment.

Microsoft is doing some of the most creative thinking along these lines, with something it's calling "Digital Manners Policies." According to its patent application, DMP-enabled devices would accept broadcast "orders" limiting capabilities. Cellphones could be remotely set to vibrate mode in restaurants and concert halls, and be turned off on airplanes and in hospitals. Cameras could be prohibited from taking pictures in locker rooms and museums, and recording equipment could be disabled in theaters. Professors finally could prevent students from texting one another during class.

The possibilities are endless, and very dangerous. Making this work involves building a nearly flawless hierarchical system of authority. That's a difficult security problem even in its simplest form. Distributing that system among a variety of different devices -- computers, phones, PDAs, cameras, recorders -- with different firmware and manufacturers, is even more difficult. Not to mention delegating different levels of authority to various agencies, enterprises, industries and individuals, and then enforcing the necessary safeguards.

Once we go down this path -- giving one device authority over other devices -- the security problems start piling up. Who has the authority to limit functionality of my devices, and how do they get that authority? What prevents them from abusing that power? Do I get the ability to override their limitations? In what circumstances, and how? Can they override my override?

How do we prevent this from being abused? Can a burglar, for example, enforce a "no photography" rule and prevent security cameras from working? Can the police enforce the same rule to avoid another Rodney King incident? Do the police get "superuser" devices that cannot be limited, and do they get "supercontroller" devices that can limit anything? How do we ensure that only they get them, and what do we do when the devices inevitably fall into the wrong hands?

It's comparatively easy to make this work in closed specialized systems -- OnStar, airplane avionics, military hardware -- but much more difficult in open-ended systems. If you think Microsoft's vision could possibly be securely designed, all you have to do is look at the dismal effectiveness of the various copy-protection and digital-rights-management systems we've seen over the years. That's a similar capabilities-enforcement mechanism, albeit simpler than these more general systems.

And that's the key to understanding this system. Don't be fooled by the scare stories of wireless devices on airplanes and in hospitals, or visions of a world where no one is yammering loudly on their cellphones in posh restaurants. This is really about media companies wanting to exert their control further over your electronics. They not only want to prevent you from surreptitiously recording movies and concerts, they want your new television to enforce good "manners" on your computer, and not allow it to record any programs. They want your iPod to politely refuse to copy music a computer other than your own. They want to enforce their legislated definition of manners: to control what you do and when you do it, and to charge you repeatedly for the privilege whenever possible.

"Digital Manners Policies" is a marketing term. Let's call this what it really is: Selective Device Jamming. It's not polite, it's dangerous. It won't make anyone more secure -- or more polite.

---

Bruce Schneier is chief security technology officer of BT, and author of Beyond Fear: Thinking Sensibly About Security in an Uncertain World.

I replied: "What's really interesting is that these people will send a tube of live ants to anyone you tell them to."

Security requires a particular mindset. Security professionals -- at least the good ones -- see the world differently. They can't walk into a store without noticing how they might shoplift. They can't use a computer without wondering about the security vulnerabilities. They can't vote without trying to figure out how to vote twice. They just can't help it.

SmartWater is a liquid with a unique identifier linked to a particular owner. "The idea is for me to paint this stuff on my valuables as proof of ownership," I wrote when I first learned about the idea. "I think a better idea would be for me to paint it on your valuables, and then call the police."

Really, we can't help it.

This kind of thinking is not natural for most people. It's not natural for engineers. Good engineering involves thinking about how things can be made to work; the security mindset involves thinking about how things can be made to fail. It involves thinking like an attacker, an adversary or a criminal. You don't have to exploit the vulnerabilities you find, but if you don't see the world that way, you'll never notice most security problems.

I've often speculated about how much of this is innate, and how much is teachable. In general, I think it's a particular way of looking at the world, and that it's far easier to teach someone domain expertise -- cryptography or software security or safecracking or document forgery -- than it is to teach someone a security mindset.

Which is why CSE 484, an undergraduate computer-security course taught this quarter at the University of Washington, is so interesting to watch. Professor Tadayoshi Kohno is trying to teach a security mindset.

You can see the results in the blog the students are keeping. They're encouraged to post security reviews about random things: smart pill boxes, Quiet Care Elder Care monitors, Apple's Time Capsule, GM's OnStar, traffic lights, safe deposit boxes, and dorm room security.

One recent one is about an automobile dealership. The poster described how she was able to retrieve her car after service just by giving the attendant her last name. Now any normal car owner would be happy about how easy it was to get her car back, but someone with a security mindset immediately thinks: "Can I really get a car just by knowing the last name of someone whose car is being serviced?"

The rest of the blog post speculates on how someone could steal a car by exploiting this security vulnerability, and whether it makes sense for the dealership to have this lax security. You can quibble with the analysis -- I'm curious about the liability that the dealership has, and whether their insurance would cover any losses -- but that's all domain expertise. The important point is to notice, and then question, the security in the first place.

The lack of a security mindset explains a lot of bad security out there: voting machines, electronic payment cards, medical devices, ID cards, internet protocols. The designers are so busy making these systems work that they don't stop to notice how they might fail or be made to fail, and then how those failures might be exploited. Teaching designers a security mindset will go a long way toward making future technological systems more secure.

That part's obvious, but I think the security mindset is beneficial in many more ways. If people can learn how to think outside their narrow focus and see a bigger picture, whether in technology or politics or their everyday lives, they'll be more sophisticated consumers, more skeptical citizens, less gullible people.

If more people had a security mindset, services that compromise privacy wouldn't have such a sizable market share -- and Facebook would be totally different. Laptops wouldn't be lost with millions of unencrypted Social Security numbers on them, and we'd all learn a lot fewer security lessons the hard way. The power grid would be more secure. Identity theft would go way down. Medical records would be more private. If people had the security mindset, they wouldn't have tried to look at Britney Spears' medical records, since they would have realized that they would be caught.

There's nothing magical about this particular university class; anyone can exercise his security mindset simply by trying to look at the world from an attacker's perspective. If I wanted to evade this particular security device, how would I do it? Could I follow the letter of this law but get around the spirit? If the person who wrote this advertisement, essay, article or television documentary were unscrupulous, what could he have done? And then, how can I protect myself from these attacks?

The security mindset is a valuable skill that everyone can benefit from, regardless of career path.

This essay originally appeared on Wired.com.

I replied: "What's really interesting is that these people will send a tube of live ants to anyone you tell them to."

Security requires a particular mindset. Security professionals -- at least the good ones -- see the world differently. They can't walk into a store without noticing how they might shoplift. They can't use a computer without wondering about the security vulnerabilities. They can't vote without trying to figure out how to vote twice. They just can't help it.

SmartWater is a liquid with a unique identifier linked to a particular owner. "The idea is for me to paint this stuff on my valuables as proof of ownership," I wrote when I first learned about the idea. "I think a better idea would be for me to paint it on your valuables, and then call the police."

Really, we can't help it.

This kind of thinking is not natural for most people. It's not natural for engineers. Good engineering involves thinking about how things can be made to work; the security mindset involves thinking about how things can be made to fail. It involves thinking like an attacker, an adversary or a criminal. You don't have to exploit the vulnerabilities you find, but if you don't see the world that way, you'll never notice most security problems.

I've often speculated about how much of this is innate, and how much is teachable. In general, I think it's a particular way of looking at the world, and that it's far easier to teach someone domain expertise -- cryptography or software security or safecracking or document forgery -- than it is to teach someone a security mindset.

Which is why CSE 484, an undergraduate computer-security course taught this quarter at the University of Washington, is so interesting to watch. Professor Tadayoshi Kohno is trying to teach a security mindset.

You can see the results in the blog the students are keeping. They're encouraged to post security reviews about random things: smart pill boxes, Quiet Care Elder Care monitors, Apple's Time Capsule, GM's OnStar, traffic lights, safe deposit boxes, and dorm room security.

One recent one is about an automobile dealership. The poster described how she was able to retrieve her car after service just by giving the attendant her last name. Now any normal car owner would be happy about how easy it was to get her car back, but someone with a security mindset immediately thinks: "Can I really get a car just by knowing the last name of someone whose car is being serviced?"

The rest of the blog post speculates on how someone could steal a car by exploiting this security vulnerability, and whether it makes sense for the dealership to have this lax security. You can quibble with the analysis -- I'm curious about the liability that the dealership has, and whether their insurance would cover any losses -- but that's all domain expertise. The important point is to notice, and then question, the security in the first place.

The lack of a security mindset explains a lot of bad security out there: voting machines, electronic payment cards, medical devices, ID cards, internet protocols. The designers are so busy making these systems work that they don't stop to notice how they might fail or be made to fail, and then how those failures might be exploited. Teaching designers a security mindset will go a long way toward making future technological systems more secure.

That part's obvious, but I think the security mindset is beneficial in many more ways. If people can learn how to think outside their narrow focus and see a bigger picture, whether in technology or politics or their everyday lives, they'll be more sophisticated consumers, more skeptical citizens, less gullible people.

If more people had a security mindset, services that compromise privacy wouldn't have such a sizable market share -- and Facebook would be totally different. Laptops wouldn't be lost with millions of unencrypted Social Security numbers on them, and we'd all learn a lot fewer security lessons the hard way. The power grid would be more secure. Identity theft would go way down. Medical records would be more private. If people had the security mindset, they wouldn't have tried to look at Britney Spears' medical records, since they would have realized that they would be caught.

There's nothing magical about this particular university class; anyone can exercise his security mindset simply by trying to look at the world from an attacker's perspective. If I wanted to evade this particular security device, how would I do it? Could I follow the letter of this law but get around the spirit? If the person who wrote this advertisement, essay, article or television documentary were unscrupulous, what could he have done? And then, how can I protect myself from these attacks?

The security mindset is a valuable skill that everyone can benefit from, regardless of career path.

This essay originally appeared on Wired.com.