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Computer Failure Causes Gridlock In MD County
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."
I smell foul play...
Quick, someone get Bruce Willis!
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.
I came to the datacenter drunk with a fake ID, don't you want to be just like me?
http://www.symantec.com/netbackup
Just throwing that out there.
~Mekkah
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.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
That wouldn't make it any better.
I haven't read the article, but if the summary correctly reflects the situation, the traffic lights are all working - they're just working independently, so rather than being in sync so the main flow of traffic never has to stop (or stops less) they're all just doing their own thing.
The preferred solution is to not have a problem.
So the default behavior is basically traffic lights in Los Angeles on a normal day? I feel soooo sorry for them. ;)
According to this it was a Data General main frame from the 1980s and not from the 1970s. Anyone know what model?
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.
Green lights are often blue to accommodate reg/green color blindness.
But you'll never make it to the interview on time, as traffic moves at the speed of my old TRS80... wait a minute...
No comprende? Let me type that a little slower for you...
I live here too and it was mayhem last night. It took me 2.5 hours to get home from work which usually takes 25 minutes. (6 miles) Many of my coworkers and friends have also reported major headaches... We were sitting at traffic lights with nowhere to go for sometimes up to 5 cycles of the lights. What I heard is that there is a different timing for rush hours that lets more traffic flow south in the morning and north in the evenings. The worst areas according to news reports are Rockville Pike, which I experienced last night, Connecticut Ave, Georgia Ave and Rt 29. The official word is that some board blew in the main computer and they are unable to find "parts" to replace it. I am not certain about the details. The county website is reporting that all traffic lights are going to have to be manually updated one-by-one. There are 800 intersections.
Wouldn't matter. The traffic lights were working fine, the problem was there was no central system that could take a larger view of traffic and sense that turning a light green a block away could prevent a gridlock issue at a specific intersection. Intelligent traffic control takes traffic that is approaching a heavily congested area and intentionally slows it down, while freeing up cars to LEAVE congested areas more quickly. They help prevent gridlock by making sure that once a specific light turns green you can actually drive through the intersection, and turns the light red BEFORE cars get caught in the middle of an intersection.
You see this kind of design a lot in well-designed roads in smaller towns. Busy towns will tend to have lots of stop signs coming in to town, but try to reduce stop signs when leaving town. The idea is to keep inbound traffic from filling the town faster than departing cars can leave by making sure cars that are leaving can do so as quickly as possible, while cars wanting to come in will be intentionally slowed down.
A meter maid has no more information about traffic flow at adjacent intersections than an autonomous single light would.
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
Here's a link: http://www.wmata.com/about_metro/news/PressReleaseDetail.cfm?ReleaseID=4133
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(Sorely needed feature: edit a post)
Fire him.
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.
Sig Battery depleted. Reverting to safe mode.
it's "password"!
This is government, you know.
It's NOT me! It's the meds! I'm on 1000mg of Fukitol.
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.
Not a typewriter
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.
I judt got a nre Kinesis keybiartf so please excusr ant egregiou typos.
I live in downtown Silver Spring. I commute from Columbia. It's usually a 30 minute drive, but last night took me an hour and a half. The worst part was when I crossed Georgia Ave a block from my home, right by the DC border. That last block took me 20 minutes.
I was trying to figure out what was up with the traffic. I didn't see any accidents or emergency vehicles, and the traffic reports I heard just said that traffic on Georgia was slow. Didn't hear anything about the control system until today.
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.
"I'm not sure I like the fugnutish tone you used in your post!" -RogL (608926)-
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.
Serious? Seriousness is well above my pay grade.
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?
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 roads that have a stop sign; almost no-one will let a left turn through, all sorts of problems like that.
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.
In this case, the article says it's just a matter of the intersections not knowing what time it is, saying "...[w]hen they were supposed to switch to morning rush mode, from 7 to 7:30, they kept rocking along at a rhythm better suited to Sunday morning."
IIRC, older systems used a dial-up modem to report problems to head office, or receive new instructions from it, whereas newer systems use DSL to communicate. The article says, "...[t]hey know where the problem is, but they just don't know what it is... The server seems to be sending the signal, but the conduit is not transferring the information to the signal lights."
The blue is from appraching the light too fast. You're aproximately going 20% the speed of light. SLOW DOWN.
Slashdot's rate-of-post filter: Preventing you from posting too many great ideas at once.
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.
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.
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.
That's our life, the big wheel of shit. - The Fat Man, Blue Tango Salvage
if the summary correctly reflects the situation
Please mod parent funny.
We barely have driver education to get your license. Actually in many states there is no requirement for drivers education if you are 18 and can pass the driving test. There are no requirements for ongoing education/training unless you count the silly 8 hour defensive driver course for those that get traffic tickets. People have trouble with the concept of yielding here.
We have a few roundabouts. Believe it or not, frequently every entrance has a stop sign instead of a yield sign. Kinda defeats the purpose.
I believe you haven't noticed the pattern. If lights are aligned vertically, the red light is ALWAYS on top and the green one ALWAYS on the bottom. If they're aligned horizontally, the red light is ALWAYS on the left. The arrangement is always the same, regardless of where the traffic light is exactly located.
Those who can, do. Those who can't, sue.
That's actually a bumper sticker I've seen around DC (Goddard Space Flight Center is in a suburb):
On a red field:
"If this sticker is blue, slow down!"
In California they get out of their cars and start looting when the power goes out. So there is not a traffic problem until the looters take to the streets and start flipping cars.
Knowledge = Power
P= W/t
t=Money
Money = Work/Knowledge so the less you know the more you make
... 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?
Biking to work in Montgomery County would be suicidal. I use mass transit and have been hit by cars while using crosswalks twice in 3 years. I simply cannot imagine the additional danger to someone who bikes to work every day surrounded by MD drivers.
What if this weren't a hypothetical question?
That's why in my town we have Braille traffic lights.
Except for one light in Buffalo, NY.
The folklore is that the Irish workmen thought that green should always be on the top.
The light has been reaplced, IIRC, several times, but remains the only inverted traffic light in the US.
"Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
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 situation.
A few years ago, the traffic light on the highway nearest to where I live, was replaced by a traffic circle (also known as a roundabout). One nice thing about a traffic circle is that there are is no longer a traffic light to fail during summer thunder storms or computer problems. There are only yield signs for traffic entering the circle. So hopefully, that Mad Max scenario you describe, would apply slightly less to my neighborhood.
Surprisingly, the traffic circle has also been able to handle much more traffic than the old traffic light did. This on a two lane highway, in a small city, in the mountains in Arizona. With the old traffic light, people at the end of the line sometimes failed to make it through the green light before it changed. With the traffic circle, it is rare that anyone needs to wait more than a few seconds before passing through the traffic circle.
I am suggesting that we should have been building more traffic circles and less traffic lights. But of course, most Americans are unfamiliar with using traffic circles, and think of them as those weird confusing European things. Traffic circles are not dependant on computers, fancy electronics or electricity.
Time to break out the bicycle. Or walk it, for that matter.
6 miles should take about an hour and a half at a decent walking pace, or about 45 minutes at a fairly leisurely cycling pace, and a week or so of it and your new sculpted bod will drive the ladies wild. :)
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
A meter maid has no more information about traffic flow at adjacent intersections than an autonomous single light would.
Then how about a Beowulf cluster of meter maids? (with walkie talkies of course)
call me FOSS im the boss with the sauce and the source
Hey, that's like traffic signals where I've live -- they're specifically timed to ensure that you consume as much gas as possible, while sitting in traffic for the maximum amount of time every day!
When I lived in Kentucky, we had an ice storm that knocked out power in Lexington for the better part of a week. The loss of traffic lights meant every intersection was supposed to turn into a 4-way stop. Which meant that every car came to a halt (in theory) at every intersection for a second or two. My 8-mile 15-minute drive to work turned into 3 hours one morning. I finally found a parking lot, parked my car there, and walked the remaining 3 miles. It was faster. Seriously - I recognized a guy 2 cars ahead of me and he arrived at work 1/2 hour after I did.
The reality was that people were assuming that dark lights meant that either (a) it was a 4-way stop, (b) people on the "larger/main" road had right-of-way, (c) I have no idea so I'm going to creep through, or (d) screw it, y'all, I've got the big fukkin truck - get outta my way.
On the third day, they deployed every police officer, meter reader, and anyone else with a pulse who was trainable to direct traffic. Of course, this meant that every bad driver in Lexington knew that all bets were off in terms of speed limits, right-of-way, and other moving violations during those times. Ever read "Lord of the Flies"? Yeah, it was like that. With cars.
"This post contains words, known to the State of California to cause thought. Wash brain thoroughly after reading."
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?
Who logs in to gdm? Not I, said the duck.
"The blue is from appraching the light too fast. You're aproximately going 20% the speed of light. SLOW DOWN"
If you're doing .2c then its going to take you months to slow down (at any acceleration the human body can take)
Let's just see you try that line on the police.
"I would have slowed down, officer, but it would have either taken too long or crushed me, so I didn't bother."
That would be called "following too closely" around these parts. Doesn't matter that if you leave a 10 foot gap to the car in front of you that 3 people will try and cram their giant SUVs in there at once while talking on their phone.
There are only 10 kinds of people in this world... those who understand binary and those who don't
Some places (like NYC) have a box painted around the intersection. If you stop inside that box you will get a ticket. It is your responsibility to know you can make it all the way though before you enter it.
Being from Buffalo I was curious that I'd never heard of that - turns out it's actually in Syracuse, which is two cities east of Buffalo (Rochester in between) and about a two and a half hour drive :)
Here's some info,
And here's a photo.
Damn, I'd mod you up but my mod points got stuck in traffic...
I did walk the final 1.5 miles, but the beginning of the commute is way too dangerous for walking. 6-8 lanes across with on/off ramps to 270 and 495. Especially with lots of impatient drivers making lots of crazy and stupid decisions. Not to mention all of the cyclists in DC who are a bunch entitled a**es. Seriously, first the take over the roads like they own them in the ridiculous spandex outfits, cycling on highways, though red lights and stop signs. And then the other day I was hiking by the C&O canal and got run off the trail by a cyclist. Oh and BTW I do get lots of exercise and am in great shape. Walk 2 miles every morning with my dag on go hiking regularly. Thanks for thew advice tho!
Cyclists don't use bike lane in DC. Perfect example is MacArthur Blvd. There is a very nice bike lane that I have used a few times, bu cyclists insist on using the road, even at rush our, which as another commenter pointed out is suicide around here.
Hmm...around here it means HIT THE GAS, otherwise you're gonna have to stop soon!!
Light travels faster than sound. This is why some people appear bright until you hear them speak.........
If you read TFA, down a ways, it seems the problem is not in the computer at all, it's in the conduit that distributes the signals. Maybe just a dope with a backhoe.
I have traveled extensively inside the USA and have never seen one such occurence. Tell me, does it appear blue to color blind people only?
The red light has a nontrivial amount of yellow and the green light a nontrivial amount of blue, for the convenience of the red-blue color blind (the commonest type of color-blindness).
For people with "normal" color vision (the commonest form of color vision, that is - there are a considerable number of rarer color vision variants), it's a lot easier to see the blue in the green light than the yellow in the red. The red light isn't obviously orangeish. But the green light is almost "teal", a color that some "normally sighted" people identify as (greenish) blue and some as (bluish) green.
I was under the impression that RED YELLOW & GREEN colors were always in the same place to accomodate color-blind people, who can still see the light shine from each spot.
Yes the position is also standardized, as an aid for the (much rarer) totally color blind.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Not necessary. My dad is color blind, and as long as the traffic engineers aren't stupid enough to install the lights upside down there's no problem -- top light means stop, bottom light means go.
He did get a ticket in Arizona once because the light was installed upside down.
He has a far greater problem with stop signs, and still curses them for changing the color from yellow to red back when I was a kid. If there's foliage behind the stop sign the sign's virtually invisible to a color blind man.
Free Martian Whores!
That's because, as a mate of mine said, European, Asian and Indian drivers are batshit insane. If everyone is batshit insane it works
If I was witty I'd put something funny here but, as it stands, I am not and have just wasted seconds of your life
The shoppers also make Rockville Pike a particularly frustrating road to travel on weekends this time of year. Given that the control system will not be repaired until at least the middle of next week, this weekend is probably going to make for some horrendous driving in that area.
Props to whoever mantains this system that the issue does occur more frequently, but this is a problem with a simple solution. Redundancy. The system is probably too old to be configurable to automatically swap, but a simple setup with two servers allowing a manual hot-swap, is all you need. Not a difficult problem to solve.
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 recursively
Have only been obtained through expert spying, done subversively,
But still for input vegetable, animal, and mineral,
I've built a better model than the one at Data General.
Maryland only this year started talking about requiring lane-changers to signal. I've been living in the DC area long enough to recognize when someone is going to change lanes in front of me by the way they drive next to me as they pass. I also learned early enough to assume everyone who drives around me is going to act in the most massively, dangerously stupid way possible, and prepare accordingly. If someone is in the far left lane of 4 and they slow down, that means they're about to cross all 4 lanes to take the exit in a couple hundred feet. I've also noticed distinct differences in the types of stupidity the drivers in the two states display. Marylanders hate the concept of any car being in front of them for more than a few feet, and if they are unable to pass, they must tailgate. Once they pass you, they can get in front of you at any point greater than 4 inches ahead of you, without signalling, because you're now behind them and no longer exist. Basically, Maryland drivers assume there is nothing important behind them, and nothing should be in front of them.
Virginians drive with the basic concept that red lights have a "freshness time" on them, so that if a light is "fresh red" it can be safely run, because everyone who has a "fresh green" light knows they can sit and wait for 5 or 10 seconds before they have to pull out, especially for left turn lanes. Virginia has a whole lot of left-hand exits off the Interstates, which is great because you can take an exit at the highest speed possible, or because you can piss off all the Maryland drivers by slowing down the fast lane in order to take the exit safely. Oh, and Marylanders will stop at a light with at least one car length of space between them and the car stopped ahead of them.
I used to tell people who don't live here that using a turn signal is a sign of weakness, because you're submitting to the other drivers' authority, you can be safely ignored, and actively prevented from merging, changing lanes, or turning, by any means necessary.
By the taping of my glasses, something geeky this way passes