Slashdot Mirror


GPS Transitions to New Control System

gsfprez writes "It took us a long time, but the Air Force has finally moved off of the 1970's mainframe GPS control system and is now running on a new Unix-based Control System called AEP — Architecture Evolution Plan. It's important to remember that current GPS satellites are basically solar powered iPod shuffles with atomic clocks that simply playback whatever we upload into them at a precise rate. They don't actually have any idea where they are — its the control system at Schriever Air Force Base that does. The new system will be a lot cheaper to support and modify since Sun stocks things like SATA drives - while digging up Saturday Night Fever-era DASDs isn't simple. AEP will also allow us to be ahead of the curve: we're basically good to go to fly the new IIF birds."

10 of 170 comments (clear)

  1. Confusion by Applekid · · Score: 3, Insightful

    ... basically solar powered iPod shuffles with atomic clocks ... cheaper to support and modify since Sun stocks things like SATA drives ... good to go to fly the new IIF birds. Is it that it's Tuesday and I've already had enough hassle to fill a week, or was anyone else thoroughly confused by TFS?
    --
    More Twoson than Cupertino
  2. wow. by White+Shade · · Score: 5, Insightful

    "Solar powered iPod shuffles with atomic clocks" ... is that the best metaphor they could come up with?!

    how media-friendly can you get, damn....

    Why not just say that they are high-precision devices that are coordinated from the ground, and that they updated the ground software to something newer and more maintainable? Why do they have to mention a completely unrelated Apple product?

    *sigh*

    --
    ìì!
    1. Re:wow. by blhack · · Score: 4, Insightful

      Actually the ipod shuffle thing confused me. Are they talking about the size of the device? Are saying that the device is meant to play music? Do they mean that it is simply powered by a battery? Seriously, I am completely failing to see any correlation between a military satelite and a white ego inflating piece of plastic that was built by the lowest bidder in some third world country.

      I propose a new godwin-esque law. First person to mention an apple product in a story that has absolutely NOTHING to do with apple gets 30 lashings.

      --
      NewslilySocial News. No lolcats allowed.
  3. Big Iron by kevmatic · · Score: 3, Insightful

    I wonder what IBM mainframe they used. If it was an 360/370, couldn't they have just upgraded to a new IBM mainframe and kept the old software, after much much testing?

    I applaud them, though, for spending the money to get this done, and get rid of all the legacy crap. It will seriously pay of in the long run, even against just upgrading the hardware. Big Old Companies still using piles of FORTRAN and COBOL should learn from this.

    1. Re:Big Iron by Detritus · · Score: 4, Insightful
      If the legacy crap works, it isn't crap. I never had a PDP-11 "blue screen" on me.

      Real programmers use FORTRAN, not the quiche-eating boutique language-of-the-month.

      --
      Mea navis aericumbens anguillis abundat
    2. Re:Big Iron by timeOday · · Score: 4, Insightful

      Is it still called a budget when you get however much money you ask for?

    3. Re:Big Iron by ChrisA90278 · · Score: 4, Insightful

      "If the legacy crap works, it isn't crap"

      I said that once too. But then we worked out the cost of maintainance and electrical power, in other words the montly cost to run and found a new system would pay it's own cost in under a year.

      Even at home I've unplugged systems simply due to the $0.24 per kilowatt hour cost to power them. (Using an old Pentium III running UNIX as a wifi router and firewall works well but sucks electrical power big time.) I actually saved money by replacing a working system. GPS did the same thing but on t much larger scale.

  4. Wait... only one base providing data refersh? by thesandbender · · Score: 3, Insightful

    So... someone dumps a high yield nuke (more likely a few high yield nukes) on one location and the whole GPS system goes to hell after a few days/weeks? Please tell me this isn't the case. Otherwise someone didn't think their cunning plan all the way through.

  5. PDP-11 by mhollis · · Score: 3, Insightful

    I crashed a descendant of a PDP-11 numerous times. And not on purpose. It was an application that may not particularly have been well-written. Butt It would generally crash at least twice weekly and you just hoped you had saved recently.

    It was an RT-11 running the CMX 3600 software.

    No BSOD but that's because it was not capable of generating a blue screen. It was green or amber. Take your pick.

    --
    Gods don't kill people, people with gods kill people.
  6. Re:It takes $800 million to replace a mainframe? by PhxBlue · · Score: 4, Insightful

    It's more than just the mainframe ... in fact, that was probably the cheap part. The expensive part was developing software that:

    • Can communicate with each of the satellites currently on-orbit. We have GPS Block II, II-A, II-R, II-R(M), and (soon) II-F satellites in orbit, and each block speaks a slightly different language.
    • Transmits the same timing and navigation data that the satellites are used to getting from the old system. I don't know much about the technical aspects of that, but I know it's not easy.
    • Is easier to maintain. I don't know what language the new system was written in, but I imagine it's easier to support than code that was written 22 years ago.
    • Works without people noticing. This is the toughest part, and it's why the Space and Missile Systems Center commander said that this is like swapping out an engine while the car's driving down the highway at 65 mph. Think about how often in the past 15 years or so you've had to worry about whether or not you would have GPS.

    A lot was on the line with this -- the Air Force has bombs and cargo pallets that rely on GPS for precision drops. The Army has a GPS-aided artillery system now. The financial sector uses the GPS timing signal for transaction management. A lot of the $800 million was no doubt an investment in testing the system so that, when it finally came online, the poop wouldn't hit the proverbial fan.

    --
    !#@%*)anks for hanging up the phone, dear.