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."

Comments

Confusion

[Applekid]

... 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?

Re:Confusion

[protolith]

Would you really want a 400 lb solar powered iPod that's the size of your refrigerator?

You would get one hell of a workout trying to jog with it clipped to your shirt!

wow.

[White Shade]

"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*

Re:wow.

[blhack]

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.

Big Iron

[kevmatic]

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.

Re:Big Iron

[Detritus]

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.

Re:Big Iron

[darkonc]

They didn't want to continue using the old software -- and, given that they wanted a complete rewrite of the old code, staying with {a seriously crufty old mainframe OS that considers terminals to be wierdass cardreader/cardpunch units} would be just silly.

The other nice thing about doing things this way is that, if the new UNIX code turns out to have nasty bugs, they can always failover to the old system. If the new system is based on an entirely new architecture, then the probability of simultaneous bugs is pleasantly low.

Re:Big Iron

[timeOday]

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

Re:Big Iron

[PhxBlue]

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

If only. Instead, the Air Force has to sack 40,000 positions in order to buy new fighters.

Re:Big Iron

[ChrisA90278]

"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.

Re:Big Iron

[hendridm]

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

Heh, you're old.

Wait... only one base providing data refersh?

[thesandbender]

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.

Re:Wait... only one base providing data refersh?

[Waffle Iron]

Following the nuclear war that would ensue from such an incident, a lack of GPS service will be the least of your worries.

Re:Wait... only one base providing data refersh?

[Starteck81]

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. Who knows, that could have been one of the driving forces behind this up grade.

Just because they didn't mention it in the article doesn't mean a backup site doesn't exist. Also if one doesn't exist then they should be able to create one much easier now that they've update to UNIX.

Man with sensational assumptions like that you should be a /. editor :-P

Amen.

[Kadin2048]

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

Truer words were never spoken.

PDP-11

[mhollis]

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.

Re:It takes $800 million to replace a mainframe?

[PhxBlue]

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.

Re:Galileo

[Anonymous Coward]

You know why the EU decided to make Galileo from this article? You mean the system of satellites that the EU may have to spend an extra 2.4 billion euro on just to get working? The one that the lead integrators want to back out of? Yeah, the ability to successfully upgrade our GPS system justifies that.

good-ol' days

[recharged95]

" 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. "

And it better stay that way.

I don't want a tomahawk crashing into my house accidentally because of some ipod/windows update or ACPI issue in the intel firmware, or since a core had to goto a wait state for some multitasking thing. Sometimes too many features bury the original intent.

Technology isn't a hammer looking for any nail.