GPS roll over-What about travel and supply?

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There is an interesting discussion going on about GPS and the grid but for some reason it seems that is the primary focus. What about other systems which use GPS? I'm placing this under the subject of "International/Global Trade."

Isn't this system used in many other areas including shipping of goods via land, sea and air?

What are the possible impacts and problems that might occur if the GPS receivers which were supposed to have been ugraded weren't? How about ships navigational equipment, etc?

Although I don't see a collapse of these systems could the system slow down?

I don't want information regarding military systems as I view this as sensitive and not necessarily or proper discussion for an open forum.

I'm very curious to know if any of these areas may see impacts due to the situation which will occur in only three weeks. I understand the essential gist of the GPS problem but it's possible impacts are still a mystery to me.

Thanks,

Mike =========================================================

-- Michael Taylor (mt4design@aol.com), August 01, 1999

Answers

The GPS seems to be huge question mark.

It affects SO MANY industries but I think people here are wary of making too much of it because of the previously over-hyped "trigger dates" There is really no connection between the GPS roll over and Y2k. (Unless you want to go into conspiracy theory land)

August 21, January 11-5 and Feb. 29th are the only dates which seem to have any truly potential for technical glitches.

It is possible that GPS is so pervasive (and arcane) that no one knows really how bad it will be. Or it could be that they are using Y2k as a way of distracting from the more immeadiate chaos to come.

Interesting times.

This from the IEE

For educational purposes only

The Institution of Electrical Engineers

W1518 Global Positioning System (GPS) and the Millennium (G3.6)

The following text is taken from an Email discussion group. As it points out systems may experience date/time-problems before the Year 2000. The writer, Joe Gwinn, says

"My intent in posting this note is to alert the entire industry to the problem, allowing it to be solved with minimal disruption to all. As a technical matter, the solution is quite simple. It's the logistics that will take some years."

Explanation/comment has been added in [ ].

GPS (Global Positioning System) consists of three segments

Space - 24 operational satellites Ground control - equipment, stations, and antennas User-antennas and receiver-processors

GPS will not have a "Year 2000" problem. The US Department of Defence (DOD) asserts that the Space and Ground Control segments will be Year 2000 compliant by Mid-year 1999.

However the GPS System Time will roll over at midnight 21-22 August 1999, 132 days before the turn of the millennium. On 22 August 1999, unless repaired, many or all GPS receivers will claim that it is 6 January 1980, 23 August will become 7 January, and so on. Some manufacturers have already solved the problem, but many have not.

All DOD user equipment is being tested for Z-count rollover capability. [The Z-kount refers to a counter for the number of weeks]. If commercial user equipment is not compatible, then in the cases of flash memory and removable PROM the memory should be reset [firmware should be upgraded. Solder-in memory will need to be physically replaced.

System software will need independent continuous data representing the current year so that it will be able to reject data from a receiver or receivers (they could all be wrong), and to handle arguments between various GPS receivers (if only some are wrong). Users can only test a GPS receiver for this problem if they have a GPS Simulator. All most users can do is to ask their manufacturer for a solution, and also to incorporate into the system software checks which will validate GPS receivers' time data.

[Addendum: In practice suppliers should be able to state whether their systems are (a) not compliant and incapable of being modified (b) not compliant but capable of modification (c) new, and designed to be compliant.]

w-87 25/09/1998 15:34

(End IEE)

This is the URL for True Time's (GPS tech folks)roll-over site http://www.truetime.com/DOCS/TThomeFRM.html

-- R (riversoma@aol.com), August 01, 1999.


Ooops typo

I meant Jan 1 - 5 NOT Jan 11-5!

Doh!

-- R (riversoma@aol.com), August 01, 1999.


Mike ....prior researce of mine on the GPS problem showed me that most of the 10,000,000. receiveing devices on the planet will reset in 15 min. or so. or power down and up again. However there is some possible problems with the timing beacons that instituions like BANKS use for accurate time on international transactions. When you figure out the interest on say $500,000,000. and your of a few seconds , sombody gets screwed alot of money.

-- Les (yoyo@tolate.com), August 01, 1999.

R:

I beg to differ on your comment that the GPS rollover is completely different than Y2K. The GPS rollover is very similar in that it is a programing "Bug". Some systems designers did not check out just how "big" the week counter was and did not realize that it was only 12bits. Many programers did not consider what would happen when 99 rolled over to 00. Both problems are inherently "end of count" design errors. Neither GPS or Y2K thought about the "carry" at the terminal count (using counter/timer design speak) and in that way they are very much the same animal.

I wonder if GPS rollover will give us the flavor of what will happen with Y2K. GPS has been widely diseminated to those that use the system, people have been told to check if their systems are compliant.

I was out fishing with some guys from JPL and they had a little hand held GPS with all the good fishing spots logged in the memory. I asked them if the unit was "rollover compliant" and they said "Say What". They did not have a clue that the roll over was comming.

The point being: if people who use GPS for critial guidance (JPL) (addmittedly the GPS in house systems at JPL are rollover compliant, so maybe they just did not get the memo) do not even know about GPS rollover (and may lose all their maps to the best fishing spots) then who else "just did not hear about it" and will get lost when GPS rolls over and their recievers are GARBAGE OUT.

This may be the wake up call... Then again, there is always SPIN Control

Things will get worse before they get better.

-- helium (heliumavid@yahoo.com), August 01, 1999.


PS: When we got back they check with the manufacturer of the hand held. It is toast. Fish 1, Anglers 0.

-- helium (heliumavid@yahoo.com), August 01, 1999.


Helium, I do realize there are parallels between the GPS roll over and Y2k. However, the fact that they are both happenning this year is a coincidence (or should be) and does not negate the potential damage of Y2k if nothing untoward occurs as a resul of the GPS roll over.

Incidentally those GPS effects may take a while to be felt so my original posting of Aug 21 may be early. I read a post (anecdotal) where somebody was being quoted saying that systems could take a couple weeks to break down if the GPS causes trouble.

-- R (riversoma@aol.com), August 01, 1999.


R;

Agreed, when "we" will feel the effects of a GPS failure is uncertian. Shipping and Transportation have the most exposure to long term effects of GPS. ie: Captain to naviagator where are we? Navigator: I don't know the clock says its 1980!

What a pickle! StarTrek could have used this as a plot for Captian Kirk.

-- helium (heliumavid@yahoo.com), August 01, 1999.


(1) The GPS problem is too improbable...would never have gotten into Star Trek. However, in real life...

(2) Electic grid, banks, telecommunications, etc. use GPS for timing. Don't know who else... Any or all could have problems with rollover.

(3) Most modern GPS navigation devices are ok... Aircraft will probably be ok (but I doubt if I'll fly out of the islands that day!). Unfortunately, not all ships or boats have modern GPS devices. Some, which are owned by third world countries, only upgrade equipment when it breaks...and good GPS used to be expensive. Most of the ships and boats will eventually find port...but there may be some delays and a few rescues.

-- Mad Monk (madmonk@hawaiian.net), August 01, 1999.


Helium,

Your JPL story reminded me of an encounter I had with a friend who uses a handheld GPS made by Garman. He also didn't know about the GPS rollover. I got the model # and checked it out on Garman's webpage, learning that my friend needed to download a patch to be compliant for the rollover. I sent him the information, and the URL for the download a few months ago...he still hasn't done it. Whenever I ask him about it, he just kind've smiles benevolently like he thinks I'm an idiot. These are the kinds of things that really make me believe people WILL NOT engage in a frenzied Y2K stockpiling panic as the feds seem to fear. I honestly believe that, even if the government did a one eighty, and used all their PR spin telling people to prepare for Y2K, most people would ignore it. They just cannot believe that technology might fail.

-- RUOK (RUOK@yesiam.com), August 01, 1999.


There shoul be very little effect on commercial transportation. Any licensed pilot or ship's captain knows how to navigate by radio beacon and/or by compass and sextant and chronometer/wristwatch. No- one is stupid enough to risk a multi-million investment on just one piece of electronics that might break for reasons that have nothing to do with roll-over.

Weekend yachtsmen and wilderness treckers who over-rely on GPS are very much at risk. (Stupid people always are!)

The two big unknowns are the military (weapons systems) and big finance (using GPS to calculate interest to the millisecond). Since the military designed GPS, one could plausibly argue that they knew about and checked for rollover compliance. The finance people ought to have backup time sources.

It's also used fairly widely for JIT delivery information (trucks that relay current location continuously to base using a GPS receiver and a mobile phone or satellite link). However, since knowing where a truck is can't do a great amount for getting it there any faster, I doubt that any breakdown on this front will be more than an annoyance. (Unless they've so downgraded the trucker job that truckers don't know how to read maps and signposts any more?)

-- Nigel Arnot (nra@maxwell.ph.kcl.ac.uk), August 02, 1999.



Please expain the connection between the EOW rollover (which affects the navigation) and the timing for banks. Sorry but banks don't use the navigational calculations for their timing. I don't get the connection.

-- Maria (anon@ymous.com), August 02, 1999.

M:

The EOW will effect GPS recievers for location, and if the reciever is not compliant it will reset to the epoch week which is in 1980? or there abouts. The GPS includes a very accurate clock which is used by many institutions (banks, power, phone, ect) in place of the old WWV and other Broadcast (Shortwave) time standards. The people who use GPS as a clock may get incorrect time information if they are not EOW compliant.

-- helium (heliumavid@yahoo.com), August 02, 1999.


Thanks for the response. So you are saying that non EOW compliant ground terminals will not know the time. Ground terminals reset the time back to epoch. I thought that the week thing was only a counter. Wouldn't that mean that the counter is just reset to zero? Is this done automatically by non-compliant terminals or does it wait for a transmission to the satellites before teh reset?

-- Maria (anon@ymous.com), August 02, 1999.

1) It's a 10 bit not 12 bit counter.

2) The better clocks can free wheel for quite a long time with micro- second accuracy if they lose signal.

3) GPS exact time is not needed in the Power Industry. This is one of the "facts" that keeps coming up on this forum that is more of a factoid.

4) You can program the receiver to think it is 550 BC if you want. Any large industry would know about the roll over. It's not secret knowledge and any GPS salesman would inform his customers about it. If for no other reason then to sell them newer clocks. Some of the older ones don't even take into account daylight savings time and have to be reset by hand.

-- The Engineer (The Engineer@tech.com), August 02, 1999.


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