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GPS Transitions to New Control System
Posted by
Zonk
on Tue Sep 18, 2007 02:03 PM
from the angels-on-our-shoulders dept.
from the angels-on-our-shoulders dept.
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."
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Yay! (Score:5, Funny)
They finally upgraded from 1970s technology to..
..Unix. Oh.
Um.
Yay!!!
Re: (Score:2)
Confusion (Score:4, Insightful)
Re:Confusion (Score:5, Funny)
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Re:Confusion (Score:5, Funny)
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Re:Confusion (Score:5, Funny)
Q: What are they going to do with a billion dollar credit at the iTunes store? They song catalog isn't nearly that big!
A: Ringtones.
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Re:Confusion (Score:4, Informative)
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Re:Confusion (Score:5, Funny)
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Re:Confusion (Score:5, Funny)
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Re: (Score:3, Insightful)
You would get one hell of a workout trying to jog with it clipped to your shirt!
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It sounds like Richard Devine.
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Roland? (Score:4, Funny)
After reading the iPod bit, I had to doublecheck to make sure the submission wasn't from you-know-how, but then I realized it both made too much sense and contained too little gobbledygook to be from him.
However, now I'm going to be anxiously watching the firehose for an article announcing Apple's new iDecay line of atomic clocks. These will be far better than the Air Force's because they'll have built in battery packs instead of relying on solar power, and offer touch sensitive screens which will redefine the paradigm of atomic clock interfaces.
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iDecay (Score:4, Funny)
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wow. (Score:5, Insightful)
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*
what your post is like (Score:5, Funny)
--Steve
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what my post is like (Score:3, Funny)
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Seriously though... why flying ipod shuffles? I just don't understand hat that has to do with anything.
oh well.
Re:wow. (Score:5, Insightful)
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.
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For all you old farts out there (Score:2)
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http://www.yoda.arachsys.com/csharp/ebcdic/ [arachsys.com]
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One thing I noticed in the DASD photo: It's totally inaccurate. -Nobody- has ever had those old cabinets with their doors shut. They were always hanging open (if they were even attached), with rats nests of cables within and without.
Epoch rollover? (Score:3, Funny)
Big Iron (Score:3, Insightful)
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 (Score:4, Funny)
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Re:Big Iron (Score:5, Insightful)
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If only. Instead, the Air Force has to sack 40,000 positions in order to buy new fighters.
Re:Big Iron (Score:5, Insightful)
Real programmers use FORTRAN, not the quiche-eating boutique language-of-the-month.
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PDP-11 (Score:4, 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 [wikipedia.org] software.
No BSOD but that's because it was not capable of generating a blue screen. It was green or amber. Take your pick.
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Re:Big Iron (Score:5, Insightful)
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.
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Re: (Score:3, Insightful)
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 b
Which Version of Unix (Score:2, Funny)
Which release of Unix are they moving to? Would that be an SCO Unix (System V Release 3.2) or SCO UnixWare (System V Release 4) :-)
Wait... only one base providing data refersh? (Score:4, Insightful)
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Re: (Score:3, Interesting)
Chip H.
Re:Wait... only one base providing data refersh? (Score:4, Interesting)
Probably not with either - as the ground control system is pretty big and delicate [1], pretty power hungry, and requires a fair number of specially trained personell [2] to operate it. It isn't something you are going to do in the back of a Humvee or a Bradley. You'd be hard pressed to do it in much of anything mobile short of the a Tico or a CVN.
That being said, the current generation of GPS birds are designed to operate autonomously for (IIRC) at least a month, though it will be some years before the entire constellation is upgraded to that standard. This implies the existence of a 'cold' backup somewhere else.
Insofar grandparents concern about 'high energy nukes' goes... He's pretty much out to lunch. The GPS constellation isn't as vulnerable to EMP/radiation effects as 'normal' LEO birds are because a) they are designed to be resistant to EMP, and b) the GPS constellation isn't inside the inner Van Allen belt like the birds wrecked by Starfish. You are pretty much in the situation of having to, even with nukes, take out each bird individually. (Sometimes they are close enough that you might be able to get 3-4, but the constellation is redundant enough that this won't take the system down.) So you are talking a pretty expensive and hard to hide endeavor, and being unable to take down enough of the cluster in a short enough timeframe to hamper US operations... before your own country is a glass parking lot.
I know many Slashdotters may have a hard time believing this - but they did actually think this stuff through when they designed the system.
[1] It's not just computers, but communications systems, precise clocks, etc... etc...
[2] Not just the techs that maintain the hardware above but the analysts that work with the incoming data to generate the corrections.
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Uploading (Score:3, Funny)
Maybe My Imagination (Score:2, Interesting)
Re:Maybe My Imagination (Score:5, Informative)
Increased bandwidth: No, absoultely not in any way. Nothing is different parameter-wise with this transition from the user perspective. In fact, that was one of the hardest parts of the transition - to make the new system interact with the user segment (thru the Space segment.. aka: the satellites) in the exact same way as the old system.
I apologize for not being more specific than that... i also stated in my submission that i am extremely hesitant to say anything unless i'm 100% sure that its public knowledge.
So, if you think i'm beating around the bush, you're right. I'm not doing it for effect.. i'm doing it to keep my job and because security is paramount.. not just for US folks, but for everyone that uses GPS.. and i hear a few people are getting into it these days... kinda like CB radios and that Internet thing.
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RDF-based space weapons (Score:4, Funny)
i was edited and my points were lost.... (Score:5, Informative)
The new system is modern. You can buy the machines from Sun today online. The OS is still updated and supported. The parts are commonplace like SATA drives, USB DVD drives, Sun workstations, etc. Unix may not be some newfangled operating system, but i can line up 1000 unix-savvy 30 year old-ish engineers and sysadmins for every one 60 year old-ish engineer that understands how to work with the IBM mainframes and jovial.
The savings comes only to US taxpayers - because its going to be way easier to for "us" (US citizens) to pay for younger engineers that are not all about to retire and younger hardware and software that shouldn't have been retired 20 years ago. "We" (US citizens) can pay less to keep GPS going now. The rest of the world.. well, i can't help you with costs since you've never paid for this thing. I'd just say "thanks" and leave it at that.
the iPod shuffle reference is to the fact that all the shuffle does is get music uploaded into it and play it back... it does *nothing* else. Okay... with that example in your mind... that's the same basic thing that GPS satellites do... "we" (US citizens) upload them with what to playback, and they play it back - and they have a clock to make sure they play it back at the right speed.... they practically do nothing more than that.
yeah, my headline was shortend to save room, but in the end, i had to end-up retyping it here. I wish they would have simply said
Re:i was edited and my points were lost.... (Score:4, Funny)
Great! When can I expect my taxes to go down because of this?
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Re:i was edited and my points were lost.... (Score:4, Interesting)
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Hope the reliability is just as good! (Score:5, Interesting)
However, I wonder who's handling the conversion for them, or if the Air Force is doing it themselves. I've seen great legacy conversion projects, and been involved in some really awful ones. One problem is just a lack of people who know enough about the "old" system to implement the software in the "new" side. The other, and far worse one is when companies (not militaries, mind you) bring in contractors who know _nothing_ about the hidden surprises in the old system, or nothing about the actual real-world application the computer is supporting.
As long as the system's not running J2EE or outsourced to a bunch of "expert" consultants, I'm guessing we're fine. But there is one key thing that's lost on "modern" IT -- proven systems work. Just because something is new doesn't mean it will work better! This is why I'm glad they stuck with UNIX instead of Linux or Windows.
Side note, how much do you think IBM was charging to maintain that monster??
Re:Hope the reliability is just as good! (Score:4, Interesting)
The 2nd Space Operations Squadron and the 19th Space Operations Squadron at Schriever Air Force Base are the primary operators of GPS. Within the squadrons, you have a wide variety of expertise -- airmen, government civilians, and contractors from the companies that developed both the new ground segment and the satellites that are on-station. Some of them are two-stripers just out of technical school
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Re: (Score:3, Funny)
> free to use resource on the planet and above it?
Catholicism?
Iridium isn't free, but it's also been a God-send.
You should have seen the old system (Score:5, Informative)
The previous system, installed at the Satellite Control Facility [209.165.152.119], or "Blue Cube" (Onizuka AFB) in Sunnyvale, was physically huge. It was the Technology that Put Men On the Moon: Philco consoles, just like in Apollo Control.
Each time a satellite needed a trajectory adjustment, it took three computers and lots of people. The signal processing was done in something called an Emulated Buffer Controller, which was a transistorized device emulating a previous tube device. The real-time processing was done on one of several UNIVAC 490 series machines from the 1960s, and the trajectory computation was done on a CDC 3800 mainframe from the 1960s.
All this gear was interconnected through big manual patchboards, where, for each satellite pass, people plugged in cables to pass data from the ground station links to the buffer controller to the UNIVAC machine to the CDC machine to the console system.
This operation just drove the satellites, not the payload. The USAF, in a very Air Force way, makes a strong distinction between "driving the bus" and operating the payload. Anything that involved commanding the satellite to move or change orientation went through the Satellite Control Facility. Payloads (GPS, cameras, receivers, etc.) were controlled by the using agencies elsewhere, over separate data links.
The SCF's ground stations had (and still have) large (20 meter) steerable dishes that can communicate with their satellites over a low-bandwidth link regardless of the satellite's orientation, even if it's tumbling. There are about eight ground stations, spaced around the world, and they can track as well as communicate. Once the satellite is properly stabilized and oriented, the wide bandwidth directional links used by the payload come up. Those use smaller ground antennas, so as not to tie up the big tracking dishes.
This was finally phased out in the late 1980s, when control moved to Falcon AFB. Still, during the entire history of the Satellite Control Facility at the Blue Cube, no satellite was ever lost due to an operational error there. That's partly why upgrades were delayed.
The upgrades generally maintained the structure of the system, without doing a complete redesign. (A complete redesign was tried once, in the early 1980s. It flopped.)
Re: (Score:3, Informative)
The system they are referring to here tracks the satellites and tells them what to say. The output will not change, just the method used to generate it.
Re:It takes $800 million to replace a mainframe? (Score:5, Insightful)
It's more than just the mainframe ... in fact, that was probably the cheap part. The expensive part was developing software that:
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.
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