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."
remind of a Cult of The Dead Cow tfile (Score:4, Interesting)
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.
MontCo $$ (Score:5, Interesting)
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:This is reassuring... (Score:5, Interesting)
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:This is reassuring... (Score:3, Interesting)
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."
Re:This is reassuring... (Score:3, Interesting)
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.
Re:From the 1980s (Score:4, Interesting)
I thought about that too. All those press references to "1970s" and "Carter-era". But these are the same geniuses in the Fourth Estate who called the thing a "mainframe", so their ignorance is manifest.
I apply the BS test here. If anyone tells me they have a Nova (even a late-model Nova 4) controlling all the traffic lights of an entire metropolitan county adjacent to the District of Columbia, will I cry shenanigans? In this case, yes. I've worked with Novas, PDP-11s, and Perkin-Elmer 16-bit minis. I'm familiar with their capabilities. You would have to be coder of absolute godly skill to write the realtime control software to safely manage dozens (scores? hundreds?) of street lights in only 64Kbytes of core (or RAM, whatever).
Whereas the most primitive Eclipse would have ample horsepower to do the trick.
So I still say Eclipse. Certainly, the comparative newness of the Eclipse over the Nova doesn't help the parts situation at all, because they're both dead as a doornail, support-wise. EMC end-of-lifed [dg.com] the last and greatest Data General line, AViiON, nearly a year ago.
Re:Report from the field: "Drivers very confused" (Score:4, Interesting)
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.
And if they had been using roundabouts... (Score:5, Interesting)
... 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?
Re:Report from the field: "Drivers very confused" (Score:5, Interesting)
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.
Re:When the system fails, shut the lights off. (Score:3, Interesting)
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.
Re:Report from the field: "Drivers very confused" (Score:3, Interesting)
"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)
Re:And if they had been using roundabouts... (Score:5, Interesting)
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.
I was just out there and it is an issue of safety (Score:1, Interesting)
I was *just* out on the affected roads in Montgomery County and I can tell you exactly why this failure of this system IS an issue of safety -- more than a few of the people who live/work/commute in this County are self-important idiots who refuse to wait 5 minutes for the traffic light to turn from red to green during rush hour so they just stomp on their car horn and proceed to drive through the red lights!!! This wasn't happening one or two cars at a time either, it was walls of them all acting as though the traffic lights were off rather than just changing more slowly than they should be.
THAT is an issue of safety.
I also saw a Montgomery County Police car drive through one such intersection while people were doing that and he/she did not stop to deal with the situation.
Ah, maybe not the "computer" (Score:2, Interesting)
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.
Re:Report from the field: "Drivers very confused" (Score:3, Interesting)
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.
Re:Report from the field: "Drivers very confused" (Score:3, Interesting)
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.
Re:All-green probably an urban legend (Score:3, Interesting)
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). When a train came, the gates would lower and all four sides would see flashing red lights. After the train passed and the gates lifted, both Bronson and Sunset traffic attempted to move immediately, then slammed on the brakes to avoid hitting each other. This happened not once but three out of the three times I was able to witness it. Now, this being Renton, it's possible that the other drivers were just retarded, but the most likely explanation is that everyone was seeing a green light. From my viewpoint I couldn't see the traffic lights pointing the other direction, so I can't be sure.
Re:From the 1980s (Score:1, Interesting)
I stopped working for the company that built the system about 3 years ago. It was a customized version of the Data General as I recall, but I can't remember the exact model it started from. It's been patch together with duct tape and bailing wire for years. Systems like it were used across the control until everybody else figured out this constituted a 'bad idea' and moved more of the processing to the controllers on the street. I worked with guys on and off for several years trying to convince them to change, but they didn't want to hear about it. It would have killed their budget for 'managing' the traffic as manually as they do (they actually have a helicopter and spotter plane they fly every day to spot trouble areas) so they were very obstinate about it. Those jokers got what they deserved.
Re:This is reassuring... (Score:3, Interesting)
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.