NTP Sync Issue Across Tata (Europe)

Mon Aug 14 14:58:42 UTC 2023

Forrest Christian (List Account) wrote:

> There are lots of ways to improve a GPS-based NTP server.  Better antenna
> positioning.  Better GPS chipset.  Paying attention to antenna patterns.
>   Adding notch filters to the GPS feed.  And so on.

They are not a very meaningful improvement.

> But, in the end, there is nothing better than adding a second
> GPS source at a diverse location as far as improving reliability, provided
> that's an option based on timing needs.

You keep ignoring DOS attacks.

Though you wrote:

: If I just want to deny you time, it gets cheaper and
: easier.   All I need is a 1.2 GHz oscillator coupled to an
: antenna. There are units like this available for under $10,
: delivered.  These block GPS trackers on trucks and/or private
: automobiles.   Build your own and you can get a watt or two
: to shove into a tiny antenna for not a lot more. Guaranteed
: to Jam anything within a couple of blocks.

you don't understand similar effectiveness by DOS.

> I can also attest that there is at least one overlap between time-nuts and
> NANOG....

See above.

						Masataka Ohta