I Like Traffic Lights

It took over a week, but the Minneapolis Traffic Light Management System is up and running again.

The computer that synchronizes the timing of about 85% of the traffic lights in Minneapolis is almost 20 years old, and it got shut down by a freak power surge.  My guess is that it wasn’t the power surge that had it down for a week, it’s the fact that the system is too dang reliable.  I have only anecdotal evidence to go by, but chances are good that the boot drive had failed a while ago and no one noticed because they never reboot the thing.  It just keeps running.

Credit where it’s due:
Traffic light management is high on the list of liability risks should something go very wrong.

  • Running an ancient system that works is sound policy.
  • Having a backup plan that keeps the lights working safely when the computer is down is sound policy.
  • Carefully planning for a replacement is also sound policy.

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