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Sensors Gone Wild
tulanian writes "forbes.com has an interesting article on networked, intelligent sensors. It mentions an experiment done by DARPA where several dozen magnetic sensors were scattered along a road and passing vehicles could be identified by their magnetic signatures."
I can imagine that many of the uses for these listed could be great, but over-reliance may be a problem. While it would be nice if everything like this worked like in Star Trek, I can imagine a story in the future where someone calls 911 about a bridge that looks about to collapse that is ignored because the sensors say the bridge is fine.
I've nothing to say here...
The world's navies have been identifying ships using magnetic signatures for decades; sophisticated mines exist which can not only distinguish friendly ships from those of the enemy from their magnetic signature, but use a combination of of the acoustic and magnetic signatures of a vessel to identify a particular ship (e.g. to distinguish one Ticonderoga class ship from another). This enables the laying of a minefield that will ignore the signatures of low value units such as minesweepers, frigates and destroyers, and only explode when a particular enemy carrier passes overhead.
One imagines that an intelligence agency wishing to assassinate a foreign president/dictator could achieve similar success using the sensors described in the Forbe's article - they need merely tune the sensors to the signature of the target's limo, and lay them on a public road on the way to his residence.
A number of suburbs of Dallas, Texas (including Carrollton, where I work) are using computerized magnetic sensors to monitor traffic. They're temporary installations -- a box about 4" x 6" x 1" high is placed in the center of the traffic lane, and covered with a thick sheet of what looks to be asphalt-impregnated duct tape.
When they're done with the traffic survey -- 24 hours, typically -- the city engineers cut out the sensor, leaving the tape that was stuck to the ground. You'll see these squares all over town -- they don't seem to disintegrate for several months, even after heavy traffic driving over them. The busiest intersections have several of these leftovers.
A Dallas Morning News article a year or so ago detailed the city's use of the boxes, and noted that they could derive detailed information about the vehicles by their magnetic signatures. I didn't put 2 and 2 together, though, until Slashdot came to the rescue...
Dallas is one of the most insanely vehicle-as-status-symbol regions of the country (according to friends who have lived elsewhere). I thought that Carrollton was simply doing a traffic survey no different than the pneumatic roll-over count... but if you can tell a '82 Chevette from a brand-new Cadillac SUV, it adds a whole new dimension.
Anyone want to bet against the cities prioritizing road repairs based on relative driver income, as opposed to mere number of vehicles?
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
Laugh at sensors hopping...
:-).
It's very funny that you link to the DARPA SHM program. The Forbes "Sensors Gone Wild" article that Slashdot linked to today is talking about work done at the Center for Embedded Network Sensing at UCLA (and the closely associated UCLA LECS lab, also run by Deborah Estrin). Now, a few of us lowly graduate students working at the UCLA lab/center also work for Sensoria Corp, which was one of the main contractors for the SHM project. A lot of the research was very complementary. I'll plug my own research here -- the fine grained network time synchronization that we developed at UCLA/LECS is public domain and also made its way into the SHM project. There's other crossover as well (e.g. some of the acoustic ranging work); check out Sensoria's publications page.
I was at the SHM demo on an army base this past March and again this past August, and let me tell you, seeing those things actually hop is quite exciting. Especially when you're the one with your finger on the "ARM ALL" button
Well, crypto would be virutally useless in this application for the military, they're not sending out communications, only recieving them. I cannot see any good reason why the military would want to use any sort of encryption on these...
Actually, there are two very good reasons why the military might want to use crypto. One is that if the sensors are actually providing useful info, the enemy might also find that information useful. If you drop sensors onto the front line, and then manage to advance the line, well now the sensors are transmitting information about the location of your own troops. So you would definitely want that encrypted.
The other is to ensure the integrity of the information. Remember, crypto has more uses than simply preserving privacy. Your sensor array wouldn't be worth a whole lot if the enemy could transmit false data. If you can't trust the sensors, you can't make decisions based upon the data you get back. Imagine if your enemy could inject fake data saying that nothings moving when in fact they are advancing? Or saying that their tanks are miles away from their actual location?
There are sensors just like these along various stretches of the border between British Columbia, Canada and Washington, USA where the two nations have parallel streets separated only by a shallow drainage ditch. They are presumably there to detect when cars stop to toss bags of marijuana over the border.