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Transportation Technology

Computer Failure Causes Gridlock In MD County 483

Uncle Rummy writes "A central traffic control computer in Montgomery County, Maryland failed early Wednesday morning, leading to widespread gridlock across the entire county. The computer, which dates to the 1970s, is the single point of unified control for all traffic signals in the county, which comprises a number of major Washington DC-area suburban communities. When the system failed, it caused all signals to default to stand-alone operation, rather than the highly-tuned synchronization that usually serves to facilitate traffic flow during rush hours. The resulting chaos is a yet another stark reminder of how much modern civilization relies on behind-the-scenes automation to deliver and control basic services and infrastructure. The system remains down Thursday, with no ETA in sight."
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Computer Failure Causes Gridlock In MD County

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  • by Monkeedude1212 ( 1560403 ) on Thursday November 05, 2009 @01:54PM (#29997000) Journal

    I smell foul play...

    Quick, someone get Bruce Willis!

    • by Deag ( 250823 )

      The washington metro's computers did crash yesterday also. So call him quick!

    • Re: (Score:3, Informative)

      by EdZ ( 755139 )
      Willis? I think you have the wrong movie [wikipedia.org].
      • by Darth_brooks ( 180756 ) <clipper377&gmail,com> on Thursday November 05, 2009 @04:16PM (#29998962) Homepage

        Bringing in Bruce Willis is *never* a bad idea. Need an asteroid destroyed in an affront to basic science? Call Willis. Need to remove an East German terrorist that can't speak proper German? Willis. Need someone to have sex with a hot, orange haired diety? Willis. Need Chuck Norris' ass kicked? Willis. Cancer cure? Willis. Making a Jaws Sequel? Have Bruce Willis play the shark.

  • Wooo Fire Sale!!

  • by trybywrench ( 584843 ) on Thursday November 05, 2009 @01:55PM (#29997018)
    back in the day i read a "tfile" by Sunspot IIRC that explained how to break into those boxes attached the stop lights at intersections and make every light stay green all the time. Not sure if it was legit or not but it sounded a little far fetched.

    As for the single computer, i bet a coke no one knows the root password, the system administrator is long gone and the programmers are very long gone. I bet the staff tried to power cycle it thinking it was just like a PC and now they've made the problem 3x worse.
    • by davidwr ( 791652 ) on Thursday November 05, 2009 @02:00PM (#29997078) Homepage Journal

      Most of those boxes have a "conflicting green" detector circuit that automatically puts the signal in "safe mode" when it detects two conflicting green lights.

      On simpler systems, "safe mode" is all-way flashing red lights.

      I guess if you knew what wires to mess with you could disable this safety feature.

      Physical access is root access.

      • by Qzukk ( 229616 ) on Thursday November 05, 2009 @02:31PM (#29997440) Journal

        After hurricane Ike blew through Houston, I ended up parking at a light that was stuck, showing green for traffic in one direction only for at least 15 minutes.

        Every time someone was brave enough to try to run the red light, someone else would drive through the green light and spook everyone. Eventually I turned right, U-turned, and turned right again.

      • Re: (Score:3, Interesting)

        by rcw-home ( 122017 )

        Most of those boxes have a "conflicting green" detector circuit that automatically puts the signal in "safe mode" when it detects two conflicting green lights.

        That's what's supposed to happen. I have anecdotal non-proof from several years ago that that may not be universal, though. In Renton, WA, just west of the Sunset Blvd intersection, Bronson Way crosses a couple railroad tracks (which recently were only used for the Spirit of Washington dinner train and have now been torn up completely in Bellevue). Wh

    • I do! (Score:3, Funny)

      by NoYob ( 1630681 )
      ...i bet a coke no one knows the root passwod,...r

      it's "password"!

      This is government, you know.

    • Re: (Score:3, Funny)

      by rainmaestro ( 996549 )

      A machine that old? The password is bound to be: sex, love, secret or god =)

  • I have an old Pentium 75. They are welcome to it, it it will help. :) Of course with the diffrence in processing power between a Pentium and a 1970's era computer, you could probably run the entire countries traffic lights with a P75.
    • Re: (Score:3, Insightful)

      by hardburn ( 141468 )

      Old systems stick around because they work. City-wide traffic systems are very complicated affairs. Getting rid of a 40 year old system also means trashing 40 years of hard lessons.

  • NBU (Score:2, Funny)

    by Mekkah ( 1651935 )
    http://www.symantec.com/netbackup [symantec.com]

    Just throwing that out there.
  • No lights is better than badly times lights.

    • by Golddess ( 1361003 ) on Thursday November 05, 2009 @02:13PM (#29997268)
      You're joking, right?

      I mean, sure, the law states that when an intersection has traffic lights, and the lights are out, it's an all-way stop. But in practice, I rarely see other drivers actually give a fuck that they are supposed to stop.
      • Re: (Score:3, Insightful)

        by jeffmeden ( 135043 )

        I have seen accidents at lightly trafficked intersections when the light was completely out... I don't want to imagine the apocalypse of a couple hundred all going out in a well populated area; it would turn into Mad Max in a matter of hours.

        • Re: (Score:3, Interesting)

          by Rick17JJ ( 744063 )
          Summer thunder storms frequently cause power outages which occasionally knock traffic lights out for up to a couple of hours, in some parts of the country. Presumably, that also happens in larger cities. I do not seem to recall hearing about any Mad Max situations resulting from that. However, I have wondered what would happen if much of our complicated technology and the power grid itself or the economic system were to collapse all across the country for a few weeks. Then, we might be in a Mad Max situat
      • by colfer ( 619105 )
        That's D.C. for you. As I recall it, California drivers are actually pretty good at that when the lights go out. The state has a lot of 4-way stop signs.
      • In my experience, when the lights are out, a bunch of people will go through the intersection and then somebody will stop, at which point a bunch of people will go from the perpendicular direction. It works out quite well.

        There is one light that I pass through on my commute that goes out for an afternoon a few times a year. On those days, traffic improves noticeably as people are better able to judge which direction is more backed up at that particular moment than a computer is.

        The computers only have a few

    • Re: (Score:2, Insightful)

      by greed ( 112493 )

      When a traffic signal in Toronto loses contact with the computer, it goes to flashing 4-way red, to remind people it's an all-way-stop now. They only go to "no signal" if there's a power failure. (In which case, they're still all-way-stop but despite the radio saying so every time there's a power failure, 70% of drivers just blow through a dark traffic light at speed.)

      I think all-way-stop on multilane roads are MUCH MUCH MUCH MUCH worse than untimed lights. People have no idea how to deal with multilane

      • Re: (Score:3, Insightful)

        by citizenr ( 871508 )

        People have no idea how to deal with multilane roads that have a stop sign; almost no-one will let a left turn through, all sorts of problems like that.

        Maybe you should teach them this and test it on Drivers License exam instead of usual round the block with automatic transmission then, eh?

  • by non0score ( 890022 ) on Thursday November 05, 2009 @02:02PM (#29997108)
    So the default behavior is basically traffic lights in Los Angeles on a normal day? I feel soooo sorry for them. ;)
  • From the 1980s (Score:5, Informative)

    by Sponge Bath ( 413667 ) on Thursday November 05, 2009 @02:03PM (#29997122)
    According to this [wtopnews.com] it was a Data General main frame from the 1980s and not from the 1970s. Anyone know what model?
    • by afidel ( 530433 )
      Hmm, I know of a company that started out as a specialist in aftermarket support for DG boxes, wonder how hard they have looked for replacement parts.
    • Hmmm... probably an Eclipse MV machine. I worked with a ten-year-old MV/10000 back in the day (early 90s). That makes it the right timeline.
    • Re: (Score:3, Informative)

      by Parker51 ( 552001 )
      More details (in PDF):

      Modernization of the Montgomery County Traffic Signal System [baltometro.org]

    • In fact when I've a floppy of a maximum diameter,
      When I can call a subroutine of infinite parameter,
      When I can point to registers and keep their current map around,
      And when I can prevent the need for mystifying wraparound,
      When I can update record blocks with minimum of suffering,
      And when I can afford to use a hundred K for buffering,
      When I've performed a matrix sort and tested the addition rate,
      You'll marvel at the speed of my asynchronous transmission rate.

      Though all my better programs that self-reference

  • MontCo $$ (Score:5, Interesting)

    by headhot ( 137860 ) on Thursday November 05, 2009 @02:03PM (#29997128) Homepage

    For those who aren't familiar with Montgomery County, MD. It is one of, if not the richest counties in the nation. I find it amazing that even in a county like this, the public infrastructure is crumbling.

    They had a massive water main break earlier this year that made the national news.

    • Re: (Score:3, Informative)

      by JWSmythe ( 446288 )

      No one fixes infrastructure until it's broken. That's pretty standard everywhere.

      Los Angeles has had an increase in water main breaks also. They fix the spot as they break. If I remember their numbers, they expect about 400 to 700 main breaks per year.

      Who cares about the old mini/mainframe running the traffic lights. If it's run since the 70's or 80's, it'll run forever. I always love that intelligence. I like to laugh about it more when it fails too. :)

      • Re: (Score:3, Insightful)

        by nomadic ( 141991 )
        No one fixes infrastructure until it's broken. That's pretty standard everywhere.

        Well, not since the tax-cut/reduce-government fanatics came into power.
        • Re: (Score:3, Informative)

          This is Montgomery County, Maryland, we're talking about -- tax-cut/reduce-government fanatics NEVER come into power here.

      • Re: (Score:3, Insightful)

        by dkleinsc ( 563838 )

        No one fixes infrastructure until it's broken. That's pretty standard everywhere.

        Sometimes not even after it's broken. Or more commonly, when it's broken, there's a half-assed temporary repair that becomes the permanent repair until it breaks again.

        The biggest reason for doing this is short-term-ism: If a politician manages to save money now, it doesn't matter to him that somebody else 10 years down the line will have to spend far more money to clean up the mess after the system failed. So each administration (at any level: state, county, and municipal governments are far from immune to

    • I find it amazing that even in a county like this, the public infrastructure is crumbling.

      Why do you find it amazing? Even in a rich county there's not much money left over for good infrastructure after all the mandatory spending on bribe and kickback entitlements.

  • by iamhigh ( 1252742 ) on Thursday November 05, 2009 @02:05PM (#29997146)
    But you'll never make it to the interview on time, as traffic moves at the speed of my old TRS80... wait a minute...
  • The upside in this is that the lights still work when the controller is down. They don't go flashing red, stay red, turn off or something worse.

    • Right. A failure of this system is not an issue of safety, just of horrible, horrible inconvenience.

      • Re: (Score:3, Interesting)

        by jimbobborg ( 128330 )

        Right. A failure of this system is not an issue of safety, just of horrible, horrible inconvenience.

        You obviously don't live in this area. When anything like this happens, road rage incidents skyrocket. Maryland has some of the worst drivers I've ever seen. And Maryland doesn't require that drivers use turn signals. I hate driving through there, especially on the highways. The posted speed limit is 55, but I get about 20% of the drivers blowing by me at over 80. Montgomery and Prince George's County are the worst of the bunch.

    • by JWSmythe ( 446288 ) <jwsmythe@@@jwsmythe...com> on Thursday November 05, 2009 @02:18PM (#29997318) Homepage Journal

          IANATE (I Am Not A Traffic Engineer), but I've had the opportunity to talk to some over the years. From what I recall of those conversations, most, if not all, traffic signals are failsafe. They cannot have colliding greens, and they won't generally just turn off. Even in the event of a power failure, they're suppose to stay up on batteries for a while.

          I have seen their failsafe behavior fail though. I was once driving on a dark foggy night. Visibility was very very poor. I was staying in my lane, but I couldn't see much else. I had a long drive in a rural area, and I was coming into an urban area. I expected to see street lights and traffic lights, but there were none. As I was driving, another car shot across the road just ahead of me, missing me by just a few feet. He didn't see the traffic light that wasn't working either. I called the police, so they could station an officer there. Their response was "Are you crazy? No one can see at that intersection. He'll get hit." Hmmm, good logic. At least no one got killed there that night.

    • Re: (Score:3, Interesting)

      by Shadyman ( 939863 )
      Indeed. However, you can take heart in the fact that each intersection has its lights controlled by a computer (an embedded microcontroller or microprocessor), which is usually installed in a grey box at one of the corners. This controls the intersection's lights, including crosswalks, and takes input from inductive sensors in most lanes. If any part of this computer fails or does not pass sanity checks, the lights flash red, requiring a team to visit the intersection's box to diagnose and fix the problem.
  • Fire him.

  • 70s computer (Score:5, Insightful)

    by icebike ( 68054 ) on Thursday November 05, 2009 @02:08PM (#29997202)

    Damn! 70s? Talk about Return on Investment.

    The WashPost, in another article touts Fragile Technology.
    I reach for my 70's era calculator and estimate the operational life of 34 years for this system. Some Fragility. Who or what at the Post has been there that long.

    Wonder if its some ancient PDP version or an small IBM mainframe. The article is scarce on details. Parts for either are getting hard to find except in the scrap market.

    Still you have to wonder why it wasn't ported to some other platform if nothing else as an exercise in disaster preparedness. Any commodity computer could do the job.

    There is a lot of stuff like this still in service. I saw a PDP 8 monitoring turbines in a hydro Power station, and asked about where they get that fixed. The reply was it never broke down, but they had stockpiled 6 replacements, tested each yearly, just because they realized how old it was. Nobody knows exactly what it does anymore.

    • Re: (Score:3, Informative)

      by Poingggg ( 103097 )

      I once visited a factory for cattle feed where all silos were controlled by an ancient PDP computer. This was a few years ago. When I asked why it was not replaced by a more modern machine the answer was that all timings for the diverse outlets of the silos (and thus the mixture of the products) were so precise that it would be nearly impossible to reproduce on another platform, taking into account things like the speed of commands executed in programming languages, processing times of cpu etc.
      I think it is

  • "You're only supposed to blow the bloody doors off!"

  • Let's not go crazy here, I mean, there's not a whole lot that's relatively modern about this if the thing was developed in the friggin' '70s and operates without an efficient backup system. If anything, it's an example of how much society would _BENEFIT_ from a modern system.
  • That's a sane default at least. Never overestimate a large software system...

    Here's a piece about traffic lights optimized for furry bicyclists... http://hembrow.blogspot.com/2008/09/default-to-green.html [blogspot.com] ... such as "having a simultaneous green phase for bikes to go in all directions at once."
  • Where? (Score:3, Funny)

    by Itninja ( 937614 ) on Thursday November 05, 2009 @02:13PM (#29997250) Homepage
    From TFA: "They know where the problem is, but they just don't know what it is," she said. "The server seems to be sending the signal, but the conduit is not transferring the information to the signal lights."

    I can tell you where it is. Right there on layer 4. Does that help? Then try layer 8.
  • by cashman73 ( 855518 ) on Thursday November 05, 2009 @02:20PM (#29997334) Journal
    I was going to say we should blame this on Windows Vista, until I saw the part about the computer system dating back to the 1970s, so that wouldn't work. Still, there's got to be some way we can put the fault on Micro$oft? Maybe the computer was in need of some necessary maintenance, and the technician whose responsibility that was was too tied up in a game of Minesweeper or Solitaire, or something?
  • ...you can always call work and say you'll be late. Unless you've got T-Mobile.

  • by HangingChad ( 677530 ) on Thursday November 05, 2009 @02:30PM (#29997434) Homepage

    The resulting chaos is a yet another stark reminder of how much modern civilization relies on behind-the-scenes automation to deliver and control basic services and infrastructure.

    Just Skynet trying to figure out how to bunch up targets when it seizes control of our Predator and Reaper UAV's.

  • by macraig ( 621737 ) <mark.a.craig@gmai[ ]om ['l.c' in gap]> on Thursday November 05, 2009 @03:05PM (#29997960)

    ... to mediate traffic instead of traffic signals, they wouldn't have needed the aging old single-point-of-failure computer in the first place, because roundabouts (a) require no computers, (b) require no electronics at all, (c) require no electricity, and (d) don't require maintenance. What's more, since they allow motorists to preserve some momentum in all but the most congested traffic, gas consumption from forced arbitrary deceleration and acceleration is reduced. The only intelligence they require isn't of the artificial sort at all, only a smidgen of it from the motorists using them. They are un-powered and self-adjusting to traffic flow.

    Would anyone like to take a stab at how much energy and man-hours is expended on the traffic signal network in the United States every year?

    • by fridaynightsmoke ( 1589903 ) on Thursday November 05, 2009 @04:27PM (#29999132) Homepage

      As a UK resident and driver in the true home of the roundabout, I wish to tell you that roundabouts are not a panacea.

      Roundabouts work best for light to moderate traffic, where all 4 directions and all movements (left turn, right turn etc) are fairly equal in demand. For heavy traffic, they very quickly congest as traffic builds on the roundabout and blocks all entry. Indeed, round here most busy/large roundabouts have traffic lights on them as well, with varying degrees of success.

      As for "gas consumption from forced arbitrary deceleration and acceleration is reduced" - I strongly disagree. Here roundabouts are used as a form of 'traffic calming', ie a deliberate obstacle to slow traffic. With a traffic light its a 50/50 chance between stopping completely and carrying on at cruising speed. With roundabouts there is always a decelerate/accelerate cycle, which depending on the design of the junction can be quite severe. In Birmingham (UK) and elsewhere. there was even a recent fad among local traffic engineers to plant high vegetation on the sightlines for approaching traffic to force all vehicles entering the roundabout to slow to below 5mph to be able to see traffic on the junction. On some examples here you have maybe 3 ft before the roundabout itself where you can see oncoming vehicles.

      Don't get me wrong, I'm not saying that roundabouts are rubbish and traffic lights are good, but theres different solutions to different problems. Replacing non-synchronised traffic lights with roundabouts in a situation with very heavy traffic would have a very much worse result.

    • by Rick17JJ ( 744063 ) on Thursday November 05, 2009 @04:42PM (#29999354)
      I have been very happy with the traffic circle which replaced the traffic light near where I live. It is on a two-lane highway in a smaller city here in Arizona.

      I was very sceptical when the state said they were planning to replace the stop light with a traffic circle. But, the traffic circle has been able to handle the traffic much more smoothly than the stoplight did. I rarely need to wait more than a few seconds to get through the traffic circle, even during rush hour. I also usually do not need to make a complete stop, which saves gas and reduces the wear on my clutch.

      As you mentioned, no electricity, computers or electronics are needed. It keeps working just fine, whenever the power occasionally goes off after a summer thunderstorm, for a few minutes.

"Conversion, fastidious Goddess, loves blood better than brick, and feasts most subtly on the human will." -- Virginia Woolf, "Mrs. Dalloway"