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Is Your GPS Naive?

Posted by CmdrTaco on from the what's-a-dikfor-anyway dept.

mi writes "Many GPS devices today will try to scan the FM bands for traffic advisories in the area to display on their screens. The signals, however, are neither authenticated nor encrypted, and one can — with commonly available electronics — construct a device to broadcast bogus advisories. Possible codes range from "bullfight ahead" to "terrorist attack"..."

16 of 291 comments (clear)

  1. An even better application: by Ph33r+th3+g(O)at · · Score: 5, Insightful

    "Speed trap ahead."

    --
    I too have felt the cold finger of injustice.
    1. Re:An even better application: by RealSurreal · · Score: 4, Funny

      Here in the UK I think you'd find it more efficient to broadcast a message when there wasn't a speed trap ahead.

  2. Now, why would there be... by jamestheprogrammer · · Score: 4, Insightful

    Why would you have a "terrorist attack" code for a traffic warning system? Okay, so I can see how maybe they might close off streets for emergency personnel, but couldn't you just leave the code at that - "Roads Closed"? I mean, if you go telling drivers that there's a terrorist attack ahead of you, they're going to panic, freak out, and maybe get into a car wreck.

    --
    "You teach a child to read and he or her will be able to pass a literacy test." - President George W. Bush
    1. Re:Now, why would there be... by HerrEkberg · · Score: 5, Funny

      That's the point of the "terrorist attack" code. Terrorists use it to create havoc, panic and destruction.

    2. Re:Now, why would there be... by UbuntuDupe · · Score: 5, Funny

      Yeah, good point. But WE are smarter than them. So ... hm, what to do. OH!!!! I know! If there's ever a terrorist attack, all of the news networks should just ignore it entirely! That way people will be in complete ignorance that it's happened. (I mean, except maybe for eyewitnesses calling friends and relatives, but that can easily be banned.)

      I mean, informing people about terrorist attacks is just playing into their hands.

      --
      Apology to Ubuntu forum.
  3. encryption cant help.. by vasanth · · Score: 5, Insightful

    the writer seems to think encryption can solve this problem, encryption cant help here as the system is unable to communicate back to negotiate the setup, and if the signals are encrypted with a predetermined key it will be susceptible to replay attacks... how different is this to a common radio channel telling its listeners that there's been a terrorist attack etc? the issue seems to be more of a hype than a real concern...

  4. Social hack - use "bullfight" for "speed trap". by khasim · · Score: 5, Funny

    If there isn't one specifically for "speed trap", then re-purpose one of the lesser used code. I'd recommend "bullfight" just because there will be very few instances of its legitimate usage.

    1. Re:Social hack - use "bullfight" for "speed trap". by portforward · · Score: 5, Insightful

      Or alternatively, you could just drive the speed limit.

    2. Re:Social hack - use "bullfight" for "speed trap". by icebrain · · Score: 5, Insightful

      I never said 100mph was safe or reasonable... but there are many, many places where the road can (and does, every day) handle traffic safely at 70-75 instead of the posted 55, or 45-50 instead of a posted 35 (excluding residential areas). Many of these restrictions are due to arbitrary laws that say, in essence, "speed limits must be X within Y miles of a city", with no regard to the actual road or what it could safely handle.

      Look up the video sometime of when a bunch of college students lined up across I-285 in Atlanta and did the posted speed limit (55). Traffic backed up for MILES behind them.

      A much bigger threat than pure speed is people who don't pay attention, and realize "Oh crap, that's my exit, four lanes away!" and proceed to cut across said four lanes. Or those who don't bother to check their blind spots when changing lanes, or don't realize that their lane is ending, or don't signal... or insist on driving slow in the left lanes.

      And again... if the purpose of limits really was to promote safety, cops wouldn't have to hide. And there would be no penalty for warning others of a speed trap, either. They don't arrest you for saying to someone, "don't rob a bank, the police will get you!" so why should saying "don't drive fast, you'll get a ticket" be any different? Oh, wait, then the local government won't get its traffic fine revenue... and God forbid that the residents pay for their government themselves...

      --
      The meek may inherit the earth, but the strong shall take the stars.
    3. Re:Social hack - use "bullfight" for "speed trap". by NMerriam · · Score: 4, Insightful

      To that end, not much brings a smile to my face more than driving at the speed limit on cruise control (which I always do) in the passing lane, and pissing-off some Type-A driver ... for it by breaking the law.


      Of course you realize that you, too, are breaking the law. Yielding to faster-moving traffic in the leftmost lane is required by law in most states -- it makes no difference whether you think the other person is going "too fast", you're still causing a safety hazard, and I know several cops who love to give out tickets to people who are causing unnecessary hazards like that.

      The speed of safe travel is not an absolute thing, when you're dealing with groups of people the safest speed to be traveling is "however fast everyone else is going", even if it is in excess of the posted limit, and traffic laws do generally reflect that.
      --
      Recursive: Adj. See Recursive.
    4. Re:Social hack - use "bullfight" for "speed trap". by fractoid · · Score: 4, Informative

      Do you really expect someone to go out to each road, and try and determine the fastest allowable speed? It is a lot easier (cheaper) just to say, every one of these roads has X for a speed limit. Oddly enough, they don't seem to mind putting in the effort to *police* speed limits.

      If we assume that each road will have a speed trap on it at least once, then they've *already got* the data to determine an appropriate speed limit as per the 85th percentile rule. Interestingly, as Wikipedia notes, "a review of available speed studies demonstrates that the posted speed limit is almost always set well below the 85th-percentile speed by as much as 8 to 12 mph (see p.88)." This indicates that in a vast majority of cases, speed limits are set according to political rather than safety concerns.
      --
      Rampant carbon sequestration destroyed the Dinosaurs' tropical paradise. I'm here to help repair the damage.
    5. Re:Social hack - use "bullfight" for "speed trap". by metamatic · · Score: 4, Insightful

      It's funny that you say that. I've been legally driving for 18 years (and a few before that, shhh). I've managed to be in 4 car accidents. I take speed limits to be a guideline of how fast I should be driving. Knowing the max speed is 65mph on a highway, but having effectively unlimited visibility ahead of me and empty roads, I tend to go faster. Lets say more than 50% of my driving has been over the speed limit.

      The 4 accidents I've been in have all been low-speed accidents (under 40mph). 3 of which were driver or vehicle failure ahead of me.

      1) Bumper tag between 4 cars ahead of me. Unable to stop for the suddenly stopped vehicle ahead of me.

      [...]

      3) Truck, no brake lights, locked up tires rear-ended stopped vehicle ahead of him. Unable to stop.

      So in 2 of your 4 accidents, you were driving too fast, and were unable to stop when something bad happened in front of you. Hence, you rear-ended someone. Presumably the insurance company held you to be at fault. You might have been driving at low speed in absolute terms, but you were clearly driving too fast--or leaving inadequate stopping distance, if you want to look at it that way.

      --
      GCHQ Quantum Insert installed. If only our tongues were made of glass, how much more careful we would be when we speak
  5. Re:Remember Boston by arthurpaliden · · Score: 4, Funny

    Because the device has batteries, wires and flashing lights so therefore it must be a terrorist device, hence the code.

    --
    Undetectable Steganography? Yep, there's an app fo
  6. Sounds familiar... by Tim+Browse · · Score: 4, Interesting

    ...I still think this is funnier.

  7. Speed-laws are not reasonable by mi · · Score: 4, Insightful

    If you have an issue with the speed limits in your town, please contact your local elected officials. Have you ever been to a city council meeting?

    In too many localities police will usually let a local resident off with a warning while ripping others off. This keeps local residents (who attend council meetings) content, and brings easy revenue (people from afar are very unlikely to challenge the tickets in local court) to the town. This selective enforcement gets documented occasionally and is a real bane of highway travel.

    NJ's Governor Corzine just had a nasty accident, because his driver (a State trooper, no less) was going 91 in a 65 mph zone (Governor's vehicle can only do that in an "emergency"). The governor will take months to recover, because the moron was not wearing his seatbelt. Neither the hypocrite trooper (who had a similar accident a few years ago), nor the hypocrite governor are expected to be punished by law, although tens of thousands drivers are fined in NJ for the same (and lesser) offenses every year — most of them without causing an accident.

    The speed laws are not reasonable — they take neither car's age and quality nor the driver's experience and health into consideration. What's too fast for an inexperienced 17- or half-blind 70-year-old driving a Buick is unreasonably slow for a healthy middle-aged driver driving a BMW...

    --
    In Soviet Washington the swamp drains you.
  8. you're the problem by nanosquid · · Score: 4, Insightful

    They said you do not have any obligation to move or go faster than the speed-limit whatsoever.

    Your primary obligation is to drive safely and avoid accidents. In most cases, that means that you don't have to go faster than the speed limit, but you still have to heed "slow traffic keep right".

    Honestly, I think your type are assholes.

    I stay with traffic flow, and I haven't gotten a moving violation in the 20 years I have had a license. And if you drive too slow in the left lane, I keep a safe distance.

    Nevertheless, I have my opinion about people like you, and let me say: you're the asshole. It's people like you who put some intellectual game ahead of the safety of people around them. You know full well that you will get some bumper-hugging type-A personality behind you who doesn't keep safe distance from you, and when you two have an accident on the highway, you're going to take other people with you and block traffic for hours. You're just as much a "type-A" personality as the person who speeds, and you're just as dangerous. It's just that you're passive-aggressive instead of simply aggressive.

    The only safe thing to do is that if the guy behind you isn't keeping a safe distance, you get out of the way. If you don't, you endanger yourself and everybody around you needlessly.