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Date:      Mon, 01 Apr 2002 03:45:48 -0800
From:      Terry Lambert <tlambert2@mindspring.com>
To:        Wilko Bulte <wkb@freebie.xs4all.nl>
Cc:        sthaug@nethelp.no, hackers@FreeBSD.ORG
Subject:   Re: GPS time.
Message-ID:  <3CA8486C.1994A39F@mindspring.com>
References:  <3CA80E9E.B091200F@mindspring.com> <47573.1017647416@verdi.nethelp.no> <3CA813AF.51ACF538@mindspring.com> <20020401130111.B37363@freebie.xs4all.nl>

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Wilko Bulte wrote:
> While not stepping up to solve the world politics: the US government
> claiming the right to define the law for everything is unnerving to
> lots of non-US (and US I suppose) people alike.
> 
> GPS is just one of these things..

I disagree.  The problem is the engineers.

When the U.S. bombed Iran during the Gulf War, the communications
came back up very quickly -- or never went down, in many cases --
because the TCP/IP protocols on which those command and control
systems were based, developed on U.S. Government funding through
DARPA, and were resiliant to damage, even to large portions of
the infrastructure.

This was a pain in the butt for the U.S., but it validated that
the same system, in the face of an attack on the U.S., would
remain operational here, too.

The GPS system, on the other hand, was designed so that "the
right people" could turn it off.  This probably means that
"the wrong people" can also turn it off, and it means that if
"the right people" ever become "the wrong people" (John Travolta
has played enough of these characters in recent movies ;^)),
they can also "turn it off".

This is actually a design flaw, from one perspective: it means
that you can't rely on the system, 100%, in a crisis situation,
since who "the right people" are may not fall on your side of
the argument, even if you were/are "the right people".

As long as engineers are willing to design things with holes
in them, then we will have things with holes in them.

If it's possible for someone to "turn off" Galileo, then the
only thing this argument devloves to is a disagreement about
who "the right people" are ("the right people" are defined as
"the people who are initially entrusted with the power switch").


To take this back around: for either system to be useful for
a timebase, you have to be relative sure that it can't lie;
I think because of this, any time server based on it can't
truly be considered "tier 1", because the time base is not
under the control of the system operator.

To note Galileo: cool name, but if it's not less expensive to
buy a receiver, and all other things are equal, then who
really cares?  All we are winning by using it is a lower
commercial value system, with a different set of hands that
can pull the plug on us.

Actually, the name is a bit inappropriate, considering the
whole project revolves around the Earth... literally.  ;^).

PS: Personally, I'd never trust a robotically driven vehicle
based on a system where someone could drive me off the cliff
by transmitting bogus data, or that would scream for me to
get back up in front of the R.V. in the middle of me making
a sandwitch because some idiot thought economic sanctions
included the inability to safely use the highway system in
an area not under their political control.

-- Terry

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