[time-nuts] Industrial control systems and IEEE 1588v2 time sync

[Poul-Henning Kamp]

In message <2072AA3475FF47539716716917CDBA99 at system071>, "Bill Hawkins" writes:

>Has anyone used IEEE 1588 to synchronize clocks on an Ethernet network?

Yes.

>I've just seen an ad for a switch that can do 1588, and looked up what
>it does.
>
>Microsecond accuracy is impressive, but what does it cost?

If you don't need microseconds, you don't need a magic switch,
1588 gets you well below 1msec on regular switches, provided
you don't overload that network segment.

Regular NTP can also get there, if you tweak the poll-rate down,
but 1588 is a more robust protocol.

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