NIST NTP servers

Eygene Ryabinkin rea+nanog at
Wed May 11 11:53:33 UTC 2016

Tue, May 10, 2016 at 04:59:02PM +0200, Stephane Bortzmeyer wrote:
> On Tue, May 10, 2016 at 10:52:28AM -0400,
>  Valdis.Kletnieks at <Valdis.Kletnieks at> wrote 
>  a message of 37 lines which said:
> > Note that they *do* have motivation to keep it working, simply
> > because so much of their *own* gear (from gear for individual
> > soldiers all the way to strategic bombers and aircraft carriers)
> > wants a working GPS signal...
> Yes, but they may switch it off for civilian use (by going encrypted,
> for instance) at any time, if it is better for *their* operations.

Civilian signals are already degraded in terms of accuracy (without
assisted GPS) and military ones are encrypted (but see [1]).  The
primary reason for encryption is, by the way, to address spoofing
issues for the mil people themselves, but it is also good not to arm
the potential enemy with the precise coordinates or to be able to
do spoofing for them.

And since many civilian, but nonetheless, vital orgs are using
civilian parts, it could be hard to shut it off without affecting some
parts of the infrastructure.  Not that nobody wants that, but it will
give an unneeded resonance and could lead to the terrible mess.

Eygene Ryabinkin, National Research Centre "Kurchatov Institute"

Always code as if the guy who ends up maintaining your code will be
a violent psychopath who knows where you live.

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