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Is Your GPS Naive?

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"..."

14 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.
  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
  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. Re:Advertising tool... by Dun+Malg · · Score: 3, Insightful

    Years ago (going on 30 years ago, now), I used to hitch-hike. It was safe then. Please. It's still just as safe as it always was (i.e. perfectly safe, unless you're unlucky or alone and female). You think the odd itinerant serial killer didn't used to pick up and murder hitchhikers in the 70's? I can cite you DOZENS of hitchhiker murders from the 70's. The only difference now is that you hear about it on the news, and advances forensic science have led to more conclusions of "definitely murdered hitchhiker", rather than the old separate results of "family in Oregon never hears from hitchhiker again" and "police unable to ID body found by Hwy 8 in Ohio".
    --
    If a job's not worth doing, it's not worth doing right.
  5. Re:Social hack - use "bullfight" for "speed trap". by portforward · · Score: 5, Insightful

    Or alternatively, you could just drive the speed limit.

  6. Re:Social hack - use "bullfight" for "speed trap". by springbox · · Score: 3, Insightful

    Contrary to the opinion of nearly every jerkwad driver on the interstate, approaching 100 MPH is not "reasonable" or safe.

  7. 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.
  8. 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.
  9. Re:Social hack - use "bullfight" for "speed trap". by icebrain · · Score: 3, Insightful

    Slow drivers in the left lane probably cause more multi-car (ie, besides themselves) accidents than speeders do, because it forces so many people to slow down, dodge them, change lanes, etc. I've seen plenty of near-accidents caused by a slow person in the left lane, but I have never seen one caused by someone merely driving fast on a road that could support it (assuming they didn't do something stupid, like weave between traffic or cut someone off). I see no harm in letting someone going faster pass you on the left, but trying to take it on yourself to be a traffic enforcer may very well be putting your life in danger. I was once riding in a rear-facing station wagon seat when the driver decided to do the speed limit in the left lane in Atlanta, and I have never felt more scared in my life, seeing all of those cars fly at me and dodge at the last second.

    I'd like to try something with people that insist the speed limit is always right. I'd like to take several minutes of video (shot from a driver's perspective) on different roads where traffic routinely exceeds the limit by a significant amount (10+). Black out the speed limit signs, and play it to those people. Ask them if they feel that traffic is moving too fast, or at a good speed. If they say it's moving at a decent speed, tell them the actual speed limit and see if they change their minds. (alternatively, cover the signs up, then have them drive the course and see how fast they go. this probably won't work if they're familiar with the area, though.)

    As far as getting such things changed, many of us have tried to talk to the pertinent elected officials and such. However, it must be something in the water at the city council buildings (and I guess this is true of all governments, regardless of size), since once they get elected, the will of the populace that elected them seems to be completely forgotten. Very few city councils are going to want to raise speed limits to reasonable values because they don't want to give up the revenue stream.

    I propose that all money from certain miscellaneous traffic offenses like speeding, seat belt violations (for adults only, not children), and red light cameras, be collected into a national- or state-level fund. The money would be held in an account, and only disbursed for certain good causes (disaster relief, maybe, or scholarships, or something like that). The idea is that we need to remove the financial incentive for local governments to issue such citations. The money needs to be placed completely out of their reach, with no possible way for them to get hold of it directly, or they just see it as a treasure chest. Maybe then, they will start enforcing for safety rather than revenue.

    I've never been to Germany, but as I understand it, they don't have nearly as many problems with accidents on their autobahns, and their speed limits are much higher. Then again, in order to drive you have to actually prove that you can. Here, the driver's test is little more than "can you go around the block without hitting anything?" There are millions of people out driving in this country that really shouldn't be driving anything more than a bicycle, like the lady who was going down the highway behind me two weeks ago, _reading_a_book_ while she was driving. I'm thinking it's easier and cheaper (not to mention more lucrative) for governments here to set low limits for everyone, in the hope that the stupid drivers will survive their accidents, rather than make the driving standards tougher.

    --
    The meek may inherit the earth, but the strong shall take the stars.
  10. 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.
  11. But you agreed to stick to them by Namarrgon · · Score: 3, Insightful

    police will usually let a local resident off with a warning while ripping others off

    OK, unfair/discriminatory/whatever, sure. But "ripping others off"? Did they break the speed limit or didn't they?

    a real bane of highway travel

    I would have said "unsafe drivers" were more of a real problem. A ticket when you break the speed limit may be annoying, but having your family wiped out by (e.g.) a drunk driver or a trucker pushing his alertness limits or a speeding NJ Governor, now THAT's a problem.

    The speed laws are not reasonable -- they take neither car's age and quality nor the driver's experience and health into consideration.

    True enough. Of course, it gets complicated if you try to write legislation that codifies something as subjective as car quality and driver experience. The commonly accepted approach is to set the limits at a reasonably low average and to let the cop use his/her discretionary judgment. Perhaps your own car or apparent experience are not sufficiently reassuring - or perhaps the cops have just seen too many middle-aged corpses in wrecked BMWs.

    You & I can argue about where the limits are set, but it's pointless. The roads are common property, the rules for sharing them are the rules we agreed to abide by when we got our licenses, and there really aren't many times when one simply must drive that fast (hint: they usually involve sirens and flashing lights).

    --
    Why would anyone engrave "Elbereth"?
  12. 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.

  13. 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
  14. Re:Social hack - use "bullfight" for "speed trap". by mysticgoat · · Score: 3, Insightful

    Pity drivers' ability and attention span haven't kept pace...

    Mod parent up.

    Sane speed limits are based on the limits of human reaction times, the physics of inertia and friction, and patterns of traffic density, types of vehicles, and frequency of exceptional events (like toddlers chasing after balls that bounce into the street). Since signage cannot be changed on a minute by minute basis, posted speeds are often lower than what would be safe for the moment. That does not make them unreasonable, nor does it suggest that the driver, from his very limited point of view, should be deciding when he can break the speed limit and get away with it.

    If and when a slashdot reader gets a license to drive, it binds him to a social contract that requires him to accept these limits. If he violates that contract, he needs to face sanctions. Those around him should also take note that this person does not abide by his agreements and is a risk in other areas, such as employment agreements, production of code that is free of time bombs and backdoors, etc, etc.